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Tuesday, March 5, 2024

Morality

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Morality
Allegory with a portrait of a Venetian senator (Allegory of the morality of earthly things), attributed to Tintoretto, 1585

Morality (from Latin moralitas 'manner, character, proper behavior') is the differentiation of intentions, decisions and actions between those that are distinguished as proper (right) and those that are improper (wrong). Morality can be a body of standards or principles derived from a code of conduct from a particular philosophy, religion or culture, or it can derive from a standard that a person believes should be universal. Morality may also be specifically synonymous with "goodness" or "rightness".

Moral philosophy includes meta-ethics, which studies abstract issues such as moral ontology and moral epistemology, and normative ethics, which studies more concrete systems of moral decision-making such as deontological ethics and consequentialism. An example of normative ethical philosophy is the Golden Rule, which states: "One should treat others as one would like others to treat oneself."

Immorality is the active opposition to morality (i.e. opposition to that which is good or right), while amorality is variously defined as an unawareness of, indifference toward, or disbelief in any particular set of moral standards and/or principles.

History

Ethics

Ethics (also known as moral philosophy) is the branch of philosophy which addresses questions of morality. The word "ethics" is "commonly used interchangeably with 'morality' ... and sometimes it is used more narrowly to mean the moral principles of a particular tradition, group, or individual." Likewise, certain types of ethical theories, especially deontological ethics, sometimes distinguish between ethics and morality.

Immanuel Kant introduced the categorical imperative: "Act only according to that maxim whereby you can, at the same time, will that it should become a universal law."

Philosopher Simon Blackburn writes that "Although the morality of people and their ethics amounts to the same thing, there is a usage that restricts morality to systems such as that of Immanuel Kant, based on notions such as duty, obligation, and principles of conduct, reserving ethics for the more Aristotelian approach to practical reasoning, based on the notion of a virtue, and generally avoiding the separation of 'moral' considerations from other practical considerations."

Descriptive and normative

In its descriptive sense, "morality" refers to personal or cultural values, codes of conduct or social mores from a society that provides these codes of conduct in which it applies and is accepted by an individual. It does not connote objective claims of right or wrong, but only refers to that which is considered right or wrong. Descriptive ethics is the branch of philosophy which studies morality in this sense.

In its normative sense, "morality" refers to whatever (if anything) is actually right or wrong, which may be independent of the values or mores held by any particular peoples or cultures. Normative ethics is the branch of philosophy which studies morality in this sense.

Realism and anti-realism

Philosophical theories on the nature and origins of morality (that is, theories of meta-ethics) are broadly divided into two classes:

  • Moral realism is the class of theories which hold that there are true moral statements that report objective moral facts. For example, while they might concede that forces of social conformity significantly shape individuals' "moral" decisions, they deny that those cultural norms and customs define morally right behavior. This may be the philosophical view propounded by ethical naturalists, but not all moral realists accept that position (e.g. ethical non-naturalists).
  • Moral anti-realism, on the other hand, holds that moral statements either fail or do not even attempt to report objective moral facts. Instead, they hold that moral sentences are either categorically false claims of objective moral facts (error theory); claims about subjective attitudes rather than objective facts (ethical subjectivism); or else do not attempt to describe the world at all but rather something else, like an expression of an emotion or the issuance of a command (non-cognitivism).

Some forms of non-cognitivism and ethical subjectivism, while considered anti-realist in the robust sense used here, are considered realist in the sense synonymous with moral universalism. For example, universal prescriptivism is a universalist form of non-cognitivism which claims that morality is derived from reasoning about implied imperatives, and divine command theory and ideal observer theory are universalist forms of ethical subjectivism which claim that morality is derived from the edicts of a god or the hypothetical decrees of a perfectly rational being, respectively.

Anthropology

Morality with practical reasoning

Practical reason is necessary for the moral agency but it is not a sufficient condition for moral agency. Real life issues that need solutions do need both rationality and emotion to be sufficiently moral. One uses rationality as a pathway to the ultimate decision, but the environment and emotions towards the environment at the moment must be a factor for the result to be truly moral, as morality is subject to culture. Something can only be morally acceptable if the culture as a whole has accepted this to be true. Both practical reason and relevant emotional factors are acknowledged as significant in determining the morality of a decision.

Tribal and territorial

Celia Green made a distinction between tribal and territorial morality. She characterizes the latter as predominantly negative and proscriptive: it defines a person's territory, including his or her property and dependents, which is not to be damaged or interfered with. Apart from these proscriptions, territorial morality is permissive, allowing the individual whatever behaviour does not interfere with the territory of another. By contrast, tribal morality is prescriptive, imposing the norms of the collective on the individual. These norms will be arbitrary, culturally dependent and 'flexible', whereas territorial morality aims at rules which are universal and absolute, such as Kant's 'categorical imperative' and Geisler's graded absolutism. Green relates the development of territorial morality to the rise of the concept of private property, and the ascendancy of contract over status.

In-group and out-group

Some observers hold that individuals apply distinct sets of moral rules to people depending on their membership of an "in-group" (the individual and those they believe to be of the same group) or an "out-group" (people not entitled to be treated according to the same rules). Some biologists, anthropologists and evolutionary psychologists believe this in-group/out-group discrimination has evolved because it enhances group survival. This belief has been confirmed by simple computational models of evolution. In simulations this discrimination can result in both unexpected cooperation towards the in-group and irrational hostility towards the out-group. Gary R. Johnson and V.S. Falger have argued that nationalism and patriotism are forms of this in-group/out-group boundary. Jonathan Haidt has noted that experimental observation indicating an in-group criterion provides one moral foundation substantially used by conservatives, but far less so by liberals.

In-group preference is also helpful at the individual level for the passing on of one's genes. For example, a mother who favors her own children more highly than the children of other people will give greater resources to her children than she will to strangers', thus heightening her children's chances of survival and her own gene's chances of being perpetuated. Due to this, within a population, there is substantial selection pressure exerted toward this kind of self-interest, such that eventually, all parents wind up favoring their own children (the in-group) over other children (the out-group).

Comparing cultures

Peterson and Seligman approach the anthropological view looking across cultures, geo-cultural areas and across millennia. They conclude that certain virtues have prevailed in all cultures they examined. The major virtues they identified include wisdom / knowledge; courage; humanity; justice; temperance; and transcendence. Each of these include several divisions. For instance humanity includes love, kindness, and social intelligence.

Still, others theorize that morality is not always absolute, contending that moral issues often differ along cultural lines. A 2014 PEW research study among several nations illuminates significant cultural differences among issues commonly related to morality, including divorce, extramarital affairs, homosexuality, gambling, abortion, alcohol use, contraceptive use, and premarital sex. Each of the 40 countries in this study has a range of percentages according to what percentage of each country believes the common moral issues are acceptable, unacceptable, or not moral issues at all. Each percentage regarding the significance of the moral issue varies greatly on the culture in which the moral issue is presented.

Advocates of a theory known as moral relativism subscribe to the notion that moral virtues are right or wrong only within the context of a certain standpoint (e.g., cultural community). In other words, what is morally acceptable in one culture may be taboo in another. They further contend that no moral virtue can objectively be proven right or wrong.  Critics of moral relativism point to historical atrocities such as infanticide, slavery, or genocide as counter arguments, noting the difficulty in accepting these actions simply through cultural lenses.

Fons Trompenaars, author of Did the Pedestrian Die?, tested members of different cultures with various moral dilemmas. One of these was whether the driver of a car would have his friend, a passenger riding in the car, lie in order to protect the driver from the consequences of driving too fast and hitting a pedestrian. Trompenaars found that different cultures had quite different expectations, from none to definite.

Anthropologists from Oxford's Institute of Cognitive & Evolutionary Anthropology (part of the School of Anthropology & Museum Ethnography) analysed ethnographic accounts of ethics from 60 societies, comprising over 600,000 words from over 600 sources and discovered what they believe to be seven universal moral rules: help your family, help your group, return favours, be brave, defer to superiors, divide resources fairly, and respect others' property.

Evolution

The development of modern morality is a process closely tied to sociocultural evolution. Some evolutionary biologists, particularly sociobiologists, believe that morality is a product of evolutionary forces acting at an individual level and also at the group level through group selection (although to what degree this actually occurs is a controversial topic in evolutionary theory). Some sociobiologists contend that the set of behaviors that constitute morality evolved largely because they provided possible survival or reproductive benefits (i.e. increased evolutionary success). Humans consequently evolved "pro-social" emotions, such as feelings of empathy or guilt, in response to these moral behaviors.

On this understanding, moralities are sets of self-perpetuating and biologically driven behaviors which encourage human cooperation. Biologists contend that all social animals, from ants to elephants, have modified their behaviors, by restraining immediate selfishness in order to improve their evolutionary fitness. Human morality, although sophisticated and complex relative to the moralities of other animals, is essentially a natural phenomenon that evolved to restrict excessive individualism that could undermine a group's cohesion and thereby reducing the individuals' fitness.

On this view, moral codes are ultimately founded on emotional instincts and intuitions that were selected for in the past because they aided survival and reproduction (inclusive fitness). Examples: the maternal bond is selected for because it improves the survival of offspring; the Westermarck effect, where close proximity during early years reduces mutual sexual attraction, underpins taboos against incest because it decreases the likelihood of genetically risky behaviour such as inbreeding.

The phenomenon of reciprocity in nature is seen by evolutionary biologists as one way to begin to understand human morality. Its function is typically to ensure a reliable supply of essential resources, especially for animals living in a habitat where food quantity or quality fluctuates unpredictably. For example, some vampire bats fail to feed on prey some nights while others manage to consume a surplus. Bats that did eat will then regurgitate part of their blood meal to save a conspecific from starvation. Since these animals live in close-knit groups over many years, an individual can count on other group members to return the favor on nights when it goes hungry (Wilkinson, 1984)

Marc Bekoff and Jessica Pierce (2009) have argued that morality is a suite of behavioral capacities likely shared by all mammals living in complex social groups (e.g., wolves, coyotes, elephants, dolphins, rats, chimpanzees). They define morality as "a suite of interrelated other-regarding behaviors that cultivate and regulate complex interactions within social groups." This suite of behaviors includes empathy, reciprocity, altruism, cooperation, and a sense of fairness. In related work, it has been convincingly demonstrated that chimpanzees show empathy for each other in a wide variety of contexts. They also possess the ability to engage in deception, and a level of social politics prototypical of our own tendencies for gossip and reputation management.

Christopher Boehm (1982) has hypothesized that the incremental development of moral complexity throughout hominid evolution was due to the increasing need to avoid disputes and injuries in moving to open savanna and developing stone weapons. Other theories are that increasing complexity was simply a correlate of increasing group size and brain size, and in particular the development of theory of mind abilities.

Psychology

Kohlberg's model of moral development

In modern moral psychology, morality is sometimes considered to change through personal development. Several psychologists have produced theories on the development of morals, usually going through stages of different morals. Lawrence Kohlberg, Jean Piaget, and Elliot Turiel have cognitive-developmental approaches to moral development; to these theorists morality forms in a series of constructive stages or domains. In the Ethics of care approach established by Carol Gilligan, moral development occurs in the context of caring, mutually responsive relationships which are based on interdependence, particularly in parenting but also in social relationships generally. Social psychologists such as Martin Hoffman and Jonathan Haidt emphasize social and emotional development based on biology, such as empathy. Moral identity theorists, such as William Damon and Mordechai Nisan, see moral commitment as arising from the development of a self-identity that is defined by moral purposes: this moral self-identity leads to a sense of responsibility to pursue such purposes. Of historical interest in psychology are the theories of psychoanalysts such as Sigmund Freud, who believe that moral development is the product of aspects of the super-ego as guilt-shame avoidance. Theories of moral development therefore tend to regard it as positive moral development: the higher stages are morally higher, though this, naturally, involves a circular argument. The higher stages are better because they are higher, but the better higher because they are better.

As an alternative to viewing morality as an individual trait, some sociologists as well as social- and discursive psychologists have taken upon themselves to study the in-vivo aspects of morality by examining how persons conduct themselves in social interaction.

A new study analyses the common perception of a decline in morality in societies worldwide and throughout history. Adam M. Mastroianni and Daniel T. Gilbert present a series of studies indicating that the perception of moral decline is an illusion and easily produced, with implications for misallocation of resources, underuse of social support, and social influence. To begin with, the authors demonstrate that people in no less than 60 nations hold the belief that morality is deteriorating continuously, and this conviction has been present for the last 70 years. Subsequently, they indicate that people ascribe this decay to the declining morality of individuals as they age and the succeeding generations. Thirdly, the authors demonstrate that people's evaluations of the morality of their peers have not decreased over time, indicating that the belief in moral decline is an illusion. Lastly, the authors explain a basic psychological mechanism that uses two well-established phenomena (distorted exposure to information and distorted memory of information) to cause the illusion of moral decline. The authors present studies that validate some of the predictions about the circumstances in which the perception of moral decline is attenuated, eliminated, or reversed (e.g., when participants are asked about the morality of people closest to them or people who lived before they were born).

Moral cognition

Moral cognition refers to cognitive processes implicated in moral judgment and decision making, and moral action. It consists of several domain-general cognitive processes, ranging from perception of a morally salient stimulus to reasoning when faced with a moral dilemma. While it is important to mention that there is not a single cognitive faculty dedicated exclusively to moral cognition, characterizing the contributions of domain-general processes to moral behavior is a critical scientific endeavor to understand how morality works and how it can be improved.

Cognitive psychologists and neuroscientists investigate the inputs to these cognitive processes and their interactions, as well as how these contribute to moral behavior by running controlled experiments. In these experiments putatively moral versus nonmoral stimuli are compared to each other, while controlling for other variables such as content or working memory load. Often, the differential neural response to specifically moral statements or scenes, are examined using functional neuroimaging experiments.

Critically, the specific cognitive processes that are involved depend on the prototypical situation that a person encounters. For instance, while situations that require an active decision on a moral dilemma may require active reasoning, an immediate reaction to a shocking moral violation may involve quick, affect-laden processes. Nonetheless, certain cognitive skills such as being able to attribute mental states—beliefs, intents, desires, emotions to oneself, and others is a common feature of a broad range of prototypical situations. In line with this, a meta-analysis found overlapping activity between moral emotion and moral reasoning tasks, suggesting a shared neural network for both tasks. The results of this meta-analysis, however, also demonstrated that the processing of moral input is affected by task demands.

Regarding the issues of morality in video games, some scholars believe that because players appear in video games as actors, they maintain a distance between their sense of self and the role of the game in terms of imagination. Therefore, the decision-making and moral behavior of players in the game are not representing player's Moral dogma.

It has been recently found that moral judgment consists in concurrent evaluations of three different components that align with precepts from three dominant moral theories (virtue ethics, deontology, and consequentialism): the character of a person (Agent-component, A); their actions (Deed-component, D); and the consequences brought about in the situation (Consequences-component, C). This, implies that various inputs of the situation a person encounters affect moral cognition.

Jonathan Haidt distinguishes between two types of moral cognition: moral intuition and moral reasoning. Moral intuition involves the fast, automatic, and affective processes that result in an evaluative feeling of good-bad or like-dislike, without awareness of going through any steps. Conversely, moral reasoning does involve conscious mental activity to reach a moral judgment. Moral reasoning is controlled and less affective than moral intuition. When making moral judgments, humans perform moral reasoning to support their initial intuitive feeling. However, there are three ways humans can override their immediate intuitive response. The first way is conscious verbal reasoning (for example, examining costs and benefits). The second way is reframing a situation to see a new perspective or consequence, which triggers a different intuition. Finally, one can talk to other people which illuminates new arguments. In fact, interacting with other people is the cause of most moral change. 

Neuroscience

The brain areas that are consistently involved when humans reason about moral issues have been investigated by multiple quantitative large-scale meta-analyses of the brain activity changes reported in the moral neuroscience literature. The neural network underlying moral decisions overlaps with the network pertaining to representing others' intentions (i.e., theory of mind) and the network pertaining to representing others' (vicariously experienced) emotional states (i.e., empathy). This supports the notion that moral reasoning is related to both seeing things from other persons' points of view and to grasping others' feelings. These results provide evidence that the neural network underlying moral decisions is probably domain-global (i.e., there might be no such things as a "moral module" in the human brain) and might be dissociable into cognitive and affective sub-systems.

Cognitive neuroscientist Jean Decety thinks that the ability to recognize and vicariously experience what another individual is undergoing was a key step forward in the evolution of social behavior, and ultimately, morality. The inability to feel empathy is one of the defining characteristics of psychopathy, and this would appear to lend support to Decety's view. Recently, drawing on empirical research in evolutionary theory, developmental psychology, social neuroscience, and psychopathy, Jean Decety argued that empathy and morality are neither systematically opposed to one another, nor inevitably complementary.

Brain areas

An essential, shared component of moral judgment involves the capacity to detect morally salient content within a given social context. Recent research implicated the salience network in this initial detection of moral content. The salience network responds to behaviorally salient events and may be critical to modulate downstream default and frontal control network interactions in the service of complex moral reasoning and decision-making processes.

The explicit making of moral right and wrong judgments coincides with activation in the ventromedial prefrontal cortex (VMPC), a region involved in valuation, while intuitive reactions to situations containing implicit moral issues activates the temporoparietal junction area, a region that plays a key role in understanding intentions and beliefs.

Stimulation of the VMPC by transcranial magnetic stimulation, or neurological lesion, has been shown to inhibit the ability of human subjects to take into account intent when forming a moral judgment. According to such investigations, TMS did not disrupt participants' ability to make any moral judgment. On the contrary, moral judgments of intentional harms and non-harms were unaffected by TMS to either the RTPJ or the control site; presumably, however, people typically make moral judgments of intentional harms by considering not only the action's harmful outcome but the agent's intentions and beliefs. So why were moral judgments of intentional harms not affected by TMS to the RTPJ? One possibility is that moral judgments typically reflect a weighted function of any morally relevant information that is available at the time. Based on this view, when information concerning the agent's belief is unavailable or degraded, the resulting moral judgment simply reflects a higher weighting of other morally relevant factors (e.g., outcome). Alternatively, following TMS to the RTPJ, moral judgments might be made via an abnormal processing route that does not take belief into account. On either account, when belief information is degraded or unavailable, moral judgments are shifted toward other morally relevant factors (e.g., outcome). For intentional harms and non-harms, however, the outcome suggests the same moral judgment as to the intention. Thus, the researchers suggest that TMS to the RTPJ disrupted the processing of negative beliefs for both intentional harms and attempted harms, but the current design allowed the investigators to detect this effect only in the case of attempted harms, in which the neutral outcomes did not afford harsh moral judgments on their own.

Similarly, individuals with a lesion of the VMPC judge an action purely on its outcome and are unable to take into account the intent of that action.

Genetics

Moral intuitions may have genetic bases. A 2022 study conducted by scholars Michael Zakharin and Timothy C. Bates, and published by the European Journal of Personality, found that moral foundations have significant genetic bases. Another study, conducted by Smith and Hatemi, similarly found significant evidence in support of moral heritability by looking at and comparing the answers of moral dilemmas between twins.

Genetics play a role in influencing prosocial behaviors and moral decision-making. Genetics contribute to the development and expression of certain traits and behaviors, including those related to morality. However, it is important to note that while genetics play a role in shaping certain aspects of moral behavior, morality itself is a multifaceted concept that encompasses cultural, societal, and personal influences as well.

Politics

If morality is the answer to the question 'how ought we to live' at the individual level, politics can be seen as addressing the same question at the social level, though the political sphere raises additional problems and challenges. It is therefore unsurprising that evidence has been found of a relationship between attitudes in morality and politics. Moral foundations theory, authored by Jonathan Haidt and colleagues, has been used to study the differences between liberals and conservatives, in this regard. Haidt found that Americans who identified as liberals tended to value care and fairness higher than loyalty, respect and purity. Self-identified conservative Americans valued care and fairness less and the remaining three values more. Both groups gave care the highest over-all weighting, but conservatives valued fairness the lowest, whereas liberals valued purity the lowest. Haidt also hypothesizes that the origin of this division in the United States can be traced to geo-historical factors, with conservatism strongest in closely knit, ethnically homogeneous communities, in contrast to port-cities, where the cultural mix is greater, thus requiring more liberalism.

Group morality develops from shared concepts and beliefs and is often codified to regulate behavior within a culture or community. Various defined actions come to be called moral or immoral. Individuals who choose moral action are popularly held to possess "moral fiber", whereas those who indulge in immoral behavior may be labeled as socially degenerate. The continued existence of a group may depend on widespread conformity to codes of morality; an inability to adjust moral codes in response to new challenges is sometimes credited with the demise of a community (a positive example would be the function of Cistercian reform in reviving monasticism; a negative example would be the role of the Dowager Empress in the subjugation of China to European interests). Within nationalist movements, there has been some tendency to feel that a nation will not survive or prosper without acknowledging one common morality, regardless of its content.

Political morality is also relevant to the behavior internationally of national governments, and to the support they receive from their host population. The Sentience Institute, co-founded by Jacy Reese Anthis, analyzes the trajectory of moral progress in society via the framework of an expanding moral circle. Noam Chomsky states that

... if we adopt the principle of universality: if an action is right (or wrong) for others, it is right (or wrong) for us. Those who do not rise to the minimal moral level of applying to themselves the standards they apply to others—more stringent ones, in fact—plainly cannot be taken seriously when they speak of appropriateness of response; or of right and wrong, good and evil. In fact, one of them, maybe the most, elementary of moral principles is that of universality, that is, If something's right for me, it's right for you; if it's wrong for you, it's wrong for me. Any moral code that is even worth looking at has that at its core somehow.

Religion

Religion and morality are not synonymous. Morality does not depend upon religion although for some this is "an almost automatic assumption". According to The Westminster Dictionary of Christian Ethics, religion and morality "are to be defined differently and have no definitional connections with each other. Conceptually and in principle, morality and a religious value system are two distinct kinds of value systems or action guides."

Positions

Within the wide range of moral traditions, religious value systems co-exist with contemporary secular frameworks such as consequentialism, freethought, humanism, utilitarianism, and others. There are many types of religious value systems. Modern monotheistic religions, such as Islam, Judaism, Christianity, and to a certain degree others such as Sikhism and Zoroastrianism, define right and wrong by the laws and rules set forth by their respective scriptures and as interpreted by religious leaders within the respective faith. Other religions spanning pantheistic to nontheistic tend to be less absolute. For example, within Buddhism, the intention of the individual and the circumstances should be accounted for in the form of Merit, to determine if an action is right or wrong termed. A further disparity between the values of religious traditions is pointed out by Barbara Stoler Miller, who states that, in Hinduism, "practically, right and wrong are decided according to the categories of social rank, kinship, and stages of life. For modern Westerners, who have been raised on ideals of universality and egalitarianism, this relativity of values and obligations is the aspect of Hinduism most difficult to understand".

Religions provide different ways of dealing with moral dilemmas. For example, there is no absolute prohibition on killing in Hinduism, which recognizes that it "may be inevitable and indeed necessary" in certain circumstances. In monotheistic traditions, certain acts are viewed in more absolute terms, such as abortion or divorce. Religion is not always positively associated with morality. Philosopher David Hume stated that, "the greatest crimes have been found, in many instances, to be compatible with a superstitious piety and devotion; Hence it is justly regarded as unsafe to draw any inference in favor of a man's morals, from the fervor or strictness of his religious exercises, even though he himself believe them sincere."

Religious value systems can also be used to justify acts that are contrary to contemporary morality, such as massacres, misogyny and slavery. For example, Simon Blackburn states that "apologists for Hinduism defend or explain away its involvement with the caste system, and apologists for Islam defend or explain away its harsh penal code or its attitude to women and infidels". In regard to Christianity, he states that the "Bible can be read as giving us a carte blanche for harsh attitudes to children, the mentally handicapped, animals, the environment, the divorced, unbelievers, people with various sexual habits, and elderly women", and notes morally suspect themes in the Bible's New Testament as well. Elizabeth Anderson likewise holds that "the Bible contains both good and evil teachings", and it is "morally inconsistent". Christian apologists address Blackburn's viewpoints and construe that Jewish laws in the Hebrew Bible showed the evolution of moral standards towards protecting the vulnerable, imposing a death penalty on those pursuing slavery and treating slaves as persons and not property. Humanists like Paul Kurtz believe that we can identify moral values across cultures, even if we do not appeal to a supernatural or universalist understanding of principles – values including integrity, trustworthiness, benevolence, and fairness. These values can be resources for finding common ground between believers and nonbelievers.

Empirical analyses

Several studies have been conducted on the empirics of morality in various countries, and the overall relationship between faith and crime is unclear. A 2001 review of studies on this topic found "The existing evidence surrounding the effect of religion on crime is varied, contested, and inconclusive, and currently, no persuasive answer exists as to the empirical relationship between religion and crime." Phil Zuckerman's 2008 book, Society without God, based on studies conducted during 14 months in Scandinavia in 2005–2006, notes that Denmark and Sweden, "which are probably the least religious countries in the world, and possibly in the history of the world", enjoy "among the lowest violent crime rates in the world [and] the lowest levels of corruption in the world".

Dozens of studies have been conducted on this topic since the twentieth century. A 2005 study by Gregory S. Paul published in the Journal of Religion and Society stated that, "In general, higher rates of belief in and worship of a creator correlate with higher rates of homicide, juvenile and early adult mortality, STD infection rates, teen pregnancy, and abortion in the prosperous democracies," and "In all secular developing democracies a centuries long-term trend has seen homicide rates drop to historical lows" with the exceptions being the United States (with a high religiosity level) and "theistic" Portugal. In a response, Gary Jensen builds on and refines Paul's study, he concludes that a "complex relationship" exists between religiosity and homicide "with some dimensions of religiosity encouraging homicide and other dimensions discouraging it". In April 2012, the results of a study which tested their subjects' pro-social sentiments were published in the Social Psychological and Personality Science journal in which non-religious people had higher scores showing that they were more motivated by their own compassion to perform pro-social behaviors. Religious people were found to be less motivated by compassion to be charitable than by an inner sense of moral obligation.

Forgetting

From Wikipedia, the free encyclopedia
 
Forgetting
The garden of oblivion, illustration for by Ephraim Moses Lilr the l
SymptomsDifficulty in remembering recent events, problems with language, disorientation, mood swings
ComplicationsDementia

Forgetting or disremembering is the apparent loss or modification of information already encoded and stored in an individual's short or long-term memory. It is a spontaneous or gradual process in which old memories are unable to be recalled from memory storage. Problems with remembering, learning and retaining new information are a few of the most common complaints of older adults. Studies show that retention improves with increased rehearsal. This improvement occurs because rehearsal helps to transfer information into long-term memory.

Forgetting curves (amount remembered as a function of time since an event was first experienced) have been extensively analyzed. The most recent evidence suggests that a power function provides the closest mathematical fit to the forgetting function.

Overview

Failing to retrieve an event does not mean that this specific event has been forever forgotten. Research has shown that there are a few health behaviors that to some extent can prevent forgetting from happening so often. One of the simplest ways to keep the brain healthy and prevent forgetting is to stay active and exercise. Staying active is important because overall it keeps the body healthy. When the body is healthy the brain is healthy and less inflamed as well. Older adults who were more active were found to have had less episodes of forgetting compared to those older adults who were less active. A healthy diet can also contribute to a healthier brain and aging process which in turn results in less frequent forgetting.

History

One of the first to study the mechanisms of forgetting was the German psychologist Hermann Ebbinghaus (1885). Using himself as the sole subject in his experiment, he memorized lists of three letter nonsense syllable words—two consonants and one vowel in the middle. He then measured his own capacity to relearn a given list of words after a variety of given time period. He found that forgetting occurs in a systematic manner, beginning rapidly and then leveling off. Although his methods were primitive, his basic premises have held true today and have been reaffirmed by more methodologically sound methods. The Ebbinghaus forgetting curve is the name of his results which he plotted out and made 2 conclusions. The first being that much of what we forget is lost soon after it is originally learned. The second being that the amount of forgetting eventually levels off.

Around the same time Ebbinghaus developed the forgetting curve, psychologist Sigmund Freud theorized that people intentionally forgot things in order to push bad thoughts and feelings deep into their unconscious, a process he called "repression". There is debate as to whether (or how often) memory repression really occurs and mainstream psychology holds that true memory repression occurs only very rarely.

One process model for memory was proposed by Richard Atkinson and Richard Shiffrin in the 1960s as a way to explain the operation of memory. This modal model of memory, also known as the Atkinson-Shiffrin model of memory, suggests there are three types of memory: sensory memory, short-term memory, and long-term memory. Each type of memory is separate in its capacity and duration. In the modal model, how quickly information is forgotten is related to the type of memory where that information is stored. Information in the first stage, sensory memory, is forgotten after only a few seconds. In the second stage, short-term memory, information is forgotten after about 20 years. While information in long-term memory can be remembered for minutes or even decades, it may be forgotten when the retrieval processes for that information fail.

Concerning unwanted memories, modern terminology divides motivated forgetting into unconscious repression (which is disputed) and conscious thought suppression.

Measurements

Forgetting can be measured in different ways all of which are based on recall:

Recall

For this type of measurement, a participant has to identify material that was previously learned. The participant is asked to remember a list of material. Later on they are shown the same list of material with additional information and they are asked to identify the material that was on the original list. The more they recognize, the less information is forgotten.

Free recall and variants

Free recall is a basic paradigm used to study human memory. In a free recall task, a subject is presented a list of to-be-remembered items, one at a time. For example, an experimenter might read a list of 20 words aloud, presenting a new word to the subject every 4 seconds. At the end of the presentation of the list, the subject is asked to recall the items (e.g., by writing down as many items from the list as possible). It is called a free recall task because the subject is free to recall the items in any order that he or she desires.

Prompted (cued) recall

Prompted recall is a slight variation of free recall that consists of presenting hints or prompts to increase the likelihood that the behavior will be produced. Usually these prompts are stimuli that were not there during the training period. Thus in order to measure the degree of forgetting, one can see how many prompts the subject misses or the number of prompts required to produce the behavior.

Relearning method

This method measures forgetting by the amount of training required to reach the previous level of performance. German psychologist Hermann Ebbinghaus (1885) used this method on himself. He memorized lists of nonsensical syllables until he could repeat the list two times without error. After a certain interval, he relearned the list and saw how long it would take him to do this task. If it took fewer times, then there had been less forgetting. His experiment was one of the first to study forgetting.

Recognition

Participants are given a list of words and that they have to remember. Then they are shown the same list of material with additional information and they are asked to identify the material that was on the original list. The more they recognize, the less information is forgotten.

Theories

The four main theories of forgetting apparent in the study of psychology are as follows:

Cue-dependent forgetting

Cue-dependent forgetting (also, context-dependent forgetting) or retrieval failure, is the failure to recall a memory due to missing stimuli or cues that were present at the time the memory was encoded. Encoding is the first step in creating and remembering a memory. How well something has been encoded in the memory can be measured by completing specific tests of retrieval. Examples of these tests would be explicit ones like cued recall or implicit tests like word fragment completion. Cue-dependent forgetting is one of five cognitive psychology theories of forgetting. This theory states that a memory is sometimes temporarily forgotten purely because it cannot be retrieved, but the proper cue can bring it to mind. A good metaphor for this is searching for a book in a library without the reference number, title, author or even subject. The information still exists, but without these cues retrieval is unlikely. Furthermore, a good retrieval cue must be consistent with the original encoding of the information. If the sound of the word is emphasized during the encoding process, the cue that should be used should also put emphasis on the phonetic quality of the word. Information is available however, just not readily available without these cues. Depending on the age of a person, retrieval cues and skills may not work as well. This is usually common in older adults but that is not always the case. When information is encoded into the memory and retrieved with a technique called spaced retrieval, this helps older adults retrieve the events stored in the memory better. There is also evidence from different studies that show age related changes in memory. These specific studies have shown that episodic memory performance does in fact decline with age and have made known that older adults produce vivid rates of forgetting when two items are combined and not encoded.

Organic causes

Forgetting that occurs through physiological damage or dilapidation to the brain are referred to as organic causes of forgetting. These theories encompass the loss of information already retained in long-term memory or the inability to encode new information again. Examples include Alzheimer's, amnesia, dementia, consolidation theory and the gradual slowing down of the central nervous system due to aging.

Interference theories

Interference theory refers to the idea that when the learning of something new causes forgetting of older material on the basis of competition between the two. This essentially states that memory's information may become confused or combined with other information during encoding, resulting in the distortion or disruption of memories. In nature, the interfering items are said to originate from an overstimulating environment. Interference theory exists in three branches: Proactive, Retroactive and Output. Retroactive and Proactive inhibition each referring in contrast to the other. Retroactive interference is when new information (memories) interferes with older information. On the other hand, proactive interference is when old information interferes with the retrieval of new information. This is sometimes thought to occur especially when memories are similar. Output Interference occurs when the initial act of recalling specific information interferes with the retrieval of the original information. Another reason why retrieval failure occurs is due to encoding failure. The information never made it to long-term memory storage. According to the level of processing theory, how well information is encoded depends on the level of processing a piece of information receives. Certain parts of information are better encoded than others; for example, information this visual imagery or that has a survival value is more easily transferred to the long-term memory storage. This theory shows a contradiction: an extremely intelligent individual is expected to forget more hastily than one who has a slow mentality. For this reason, an intelligent individual has stored up more memory in his mind which will cause interferences and impair their ability to recall specific information. Based on current research, testing interference has only been carried out by recalling from a list of words rather than using situation from daily lives, thus it is hard to generalize the findings for this theory. It has been found that interference related tasks decreased memory performance by up to 20%, with negative effects at all interference time points and large variability between participants concerning both the time point and the size of maximal interference. Furthermore, fast learners seem to be more affected by interference than slow learners. People are also less likely to recall items when intervening stimuli are presented within the first ten minutes after learning. Recall performance is better without interference. Peripheral processes such as encoding time, recognition memory and motor execution decline with age. However proactive interference is similar. Suggesting contrary to earlier reports that the inhibitory processes observed with this paradigm remain intact in older adults.

Trace decay theory

Decay theory states that when something new is learned, a neurochemical, physical "memory trace" is formed in the brain and over time this trace tends to disintegrate, unless it is occasionally used. Decay theory states the reason we eventually forget something or an event is because the memory of it fades with time. If we do not attempt to look back at an event, the greater the interval time between the time when the event from happening and the time when we try to remember, the memory will start to fade. Time is the greatest impact in remembering an event.

Trace decay theory explains memories that are stored in both short-term and long-term memory system, and assumes that the memories leave a trace in the brain. According to this theory, short-term memory (STM) can only retain information for a limited amount of time, around 15 to 30 seconds unless it is rehearsed. If it is not rehearsed, the information will start to gradually fade away and decay. Donald Hebb proposed that incoming information causes a series of neurons to create a neurological memory trace in the brain which would result in change in the morphological and/or chemical changes in the brain and would fade with time. Repeated firing causes a structural change in the synapses. Rehearsal of repeated firing maintains the memory in STM until a structural change is made. Therefore, forgetting happens as a result of automatic decay of the memory trace in brain. This theory states that the events between learning and recall have no effects on recall; the important factor that affects is the duration that the information has been retained. Hence, as longer time passes more of traces are subject to decay and as a result the information is forgotten.

One major problem about this theory is that in real-life situation, the time between encoding a piece of information and recalling it, is going to be filled with all different kinds of events that might happen to the individual. Therefore, it is difficult to conclude that forgetting is a result of only the time duration. It is also important to consider the effectiveness of this theory. Although it seems very plausible, it is about impossible to test. It is difficult to create a situation where there is a blank period of time between presenting the material and recalling it later.

This theory is supposedly contradicted by the fact that one is able to ride a bike even after not having done so for decades. "Flashbulb memories" are another piece of seemingly contradicting evidence. It is believed that certain memories "trace decay" while others do not. Sleep is believed to play a key role in halting trace decay, although the exact mechanism of this is unknown.

Physical and chemical changes in our brain lead to a memory trace, and this is based on the idea of the trace theory of memory. Information that gets into our short-term memory lasts a few seconds (15–20 seconds), and it fades away if it is not rehearsed or practiced as the neurochemical memory trace disappears rapidly. According to the trace decay theory of forgetting, what occurs between the creation of new memories and the recall of these memories is not influenced by the recall. However, the time between these events (memory formation and recalling) decides whether the information can be kept or forgotten. As there is an inverse correlation that if the time is short, more information can be recalled. On the other hand, if the time is long less information can be recalled or more information will be forgotten. This theory can be criticized for not sharing ideas on how some memories can stay and others can fade, though there was a long time between the formation and recall. Newness to something plays a crucial role in this situation. For instance, people are more likely to recall their very first day abroad than all of the intervening days between it and living there. Emotions also play a crucial role in this situation.

Impairments and lack of forgetting

Forgetting can have very different causes than simply removal of stored content. Forgetting can mean access problems, availability problems, or can have other reasons such as amnesia caused by an accident.

An inability to forget can cause distress, as with post-traumatic stress disorder and hyperthymesia (in which people have an extremely detailed autobiographical memory).

Social forgetting

Psychologists have called attention to "social aspects of forgetting". Though often loosely defined, social amnesia is generally considered to be the opposite of collective memory. "Social amnesia" was first discussed by Russell Jacoby, yet his use of the term was restricted to a narrow approach, which was limited to what he perceived to be a relative neglect of psychoanalytical theory in psychology. The cultural historian Peter Burke suggested that "it may be worth investigating the social organization of forgetting, the rules of exclusion, suppression or repression, and the question of who wants whom to forget what". In an in-depth historical study spanning two centuries, Guy Beiner proposed the term "social forgetting", which he distinguished from crude notions of "collective amnesia" and "total oblivion", arguing that "social forgetting is to be found in the interface of public silence and more private remembrance". The philosopher Walter Benjamin sees social forgetting closely linked to the question of present-day interests, arguing that "every image of the past that is not recognized by the present as one of its own concerns threatens to disappear irretrievably". Building on this, the sociologist David Leupold argued in the context of competing national narratives that what is suppressed and forgotten in one national narrative "might appear at the core of past narrations by the other" - thus often leading to diametrically opposed, mutually exclusive accounts on the past.

Long-term memory

From Wikipedia, the free encyclopedia

Long-term memory (LTM) is the stage of the Atkinson–Shiffrin memory model in which informative knowledge is held indefinitely. It is defined in contrast to sensory memory, the initial stage, and short-term or working memory, the second stage, which persists for about 18 to 30 seconds. LTM is grouped into two categories known as explicit memory (declarative memory) and implicit memory (non-declarative memory). Explicit memory is broken down into episodic and semantic memory, while implicit memory includes procedural memory and emotional conditioning.

Stores

The idea of separate memories for short- and long-term storage originated in the 19th century. One model of memory developed in the 1960s assumed that all memories are formed in one store and transfer to another store after a small period of time. This model is referred to as the "modal model", most famously detailed by Shiffrin. The model states that memory is first stored in sensory memory, which has a large capacity but can only maintain information for milliseconds. A representation of that rapidly decaying memory is moved to short-term memory. Short-term memory does not have a large capacity like sensory memory but holds information for seconds or minutes. The final storage is long-term memory, which has a very large capacity and is capable of holding information possibly for a lifetime.

The exact mechanisms by which this transfer takes place, whether all or only some memories are retained permanently, and even to have the existence of a genuine distinction between stores, remain controversial.

Evidence

Anterograde amnesia

One form of evidence cited in favor of the existence of a short-term store comes from anterograde amnesia, the inability to learn new facts and episodes. Patients with this form of amnesia have an intact ability to retain small amounts of information over short time scales (up to 30 seconds) but have little ability to form longer-term memories (illustrated by patient HM). This is interpreted as showing that the short-term store is protected from damage and diseases.

Distraction tasks

Other evidence comes from experimental studies showing that some manipulations impair memory for the 3 to 5 most recently learned words of a list (it is presumed that they are held in short-term memory). Recall for words from earlier in the list (it is presumed, stored in long-term memory) are unaffected. Other manipulations (e.g., semantic similarity of the words) affect only memory for earlier list words, but do not affect memory for the most recent few words. These results show that different factors affect short-term recall (disruption of rehearsal) and long-term recall (semantic similarity). Together, these findings show that long-term memory and short-term memory can vary independently of each other.

Models

Unitary model

Not all researchers agree that short- and long-term memory are separate systems. The alternative Unitary Model proposes that short-term memory consists of temporary activations of long-term representations (that there is one memory that behaves variously over all time scales, from milliseconds to years). It has been difficult to identify a sharp boundary between short- and long-term memory. Eugen Tarnow, a physics researcher, reported that the recall probability versus latency curve is a straight line from 6 to 600 seconds, with the probability of failure to recall only saturating after 600 seconds. If two different stores were operating in this time domain, it is reasonable to expect a discontinuity in this curve. Other research has shown that the detailed pattern of recall errors looks remarkably similar to recall of a list immediately after learning (it is presumed, from short-term memory) and recall after 24 hours (necessarily from long-term memory).

Further evidence for a unified store comes from experiments involving continual distractor tasks. In 1974, Bjork and Whitten, psychology researchers, presented subjects with word pairs to remember; before and after each word pair, subjects performed a simple multiplication task for 12 seconds. After the final word-pair, subjects performed the multiplication distractor task for 20 seconds. They reported that the recency effect (the increased probability of recall of the last items studied) and the primacy effect (the increased probability of recall of the first few items) was sustained. These results are incompatible with a separate short-term memory as the distractor items should have displaced some of the word-pairs in the buffer, thereby weakening the associated strength of the items in long-term memory.

Ovid Tzeng (1973) reported an instance where the recency effect in free recall did not seem to result from a short-term memory store. Subjects were presented with four study-test periods of 10-word lists, with a continual distractor task (20-second period of counting-backward). At the end of each list, participants had to free recall as many words as possible. After recall of the fourth list, participants were asked to recall items from all four lists. Both the initial and final recall showed a recency effect. These results violated the predictions of a short-term memory model, where no recency effect would be expected.

Koppenaal and Glanzer (1990) attempted to explain these phenomena as a result of the subjects' adaptation to the distractor task, which allowed them to preserve at least some short-term memory capabilities. In their experiment, the long-term recency effect disappeared when the distractor after the last item differed from the distractors that preceded and followed the other items (e.g., arithmetic distractor task and word reading distractor task). Thapar and Greene challenged this theory. In one of their experiments, participants were given a different distractor task after every study item. According to Koppenaal and Glanzer's theory, no recency effect would be expected as subjects would not have had time to adapt to the distractor; yet such a recency effect remained in place in the experiment.

Another explanation

One proposed explanation for recency in a continual distractor condition, and its disappearance in an end-only distractor task is the influence of contextual and distinctive processes. According to this model, recency is a result of the similarity of the final items' processing context to the processing context of the other items and the distinctive position of the final items versus intermediate items. In the end distractor task, the processing context of the final items is no longer similar to that of the other list items. At the same time, retrieval cues for these items are no longer as effective as without the distractor. Therefore, recency recedes or vanishes. However, when distractor tasks are placed before and after each item, recency returns, because all the list items have similar processing context.

Dual-store memory model

According to George Miller, whose paper in 1956 popularized the theory of the "magic number seven", short-term memory is limited to a certain number of chunks of information, while long-term memory has a limitless store.

Atkinson–Shiffrin memory model

According to the dual store memory model proposed in 1968 by Richard C. Atkinson and Richard Shiffrin, memories can reside in the short-term "buffer" for a limited time while they are simultaneously strengthening their associations in LTM. When items are first presented, they enter short-term memory for approximately twenty to thirty seconds, but due to its limited space, as new items enter, older ones are pushed out. The limit of items that can be held in the short-term memory is an average between four and seven, yet, with practice and new skills that number can be increased. However, each time an item in short-term memory is rehearsed, it is strengthened in long-term memory. Similarly, the longer an item stays in short-term memory, the stronger its association becomes in long-term memory.

Baddeley's model of working memory

In 1974, Baddeley and Hitch proposed an alternative theory of short-term memory, Baddeley's model of working memory. According to this theory, short-term memory is divided into different slave systems for different types of input items, and there is an executive control supervising what items enter and exit those systems. The slave systems include the phonological loop, the visuo-spatial sketchpad, and the episodic buffer (later added by Baddeley).

Encoding of information

LTM encodes information semantically for storage, as researched by Baddeley. In vision, the information needs to enter working memory before it can be stored into LTM. This is evidenced by the fact that the speed with which information is stored into LTM is determined by the amount of information that can be fit, at each step, into visual working memory. In other words, the larger the capacity of working memory for certain stimuli, the faster will these materials be learned.

Synaptic consolidation is the process by which items are transferred from short- to long-term memory. Within the first minutes or hours after acquisition, the engram (memory trace) is encoded within synapses, becoming resistant (though not immune) to interference from outside sources.

As LTM is subject to fading in the natural forgetting process, maintenance rehearsal (several recalls/retrievals of memory) may be needed to preserve long-term memories. Individual retrievals can take place in increasing intervals in accordance with the principle of spaced repetition. This can happen quite naturally through reflection or deliberate recall (also known as recapitulation), often dependent on the perceived importance of the material. Using testing methods as a form of recall can lead to the testing effect, which aids long-term memory through information retrieval and feedback.

In LTM, brain cells fire in specific patterns. When someone experiences something in the world, the brain responds by creating a pattern of specific nerves firing in a specific way to represent the experience. This is called distributed representation. Distributed representation can be explained through a scientific calculator. At the top of the calculator is an opening in which the numbers typed in show up. This small slot is compiled by many blocks that light up to show a specific number. In that sense, certain blocks light up when prompted to show the number 4, but other blocks light up to show the number 5. There may be overlap in the blocks used, but ultimately, these blocks are able to generate different patterns for each specific situation. The encoding of specific episodic memories can be explained through distributed representation. When you try to remember an experience, perhaps your friend's birthday party a year ago, your brain is activating a certain pattern of neurons. If you try to remember your mother's birthday party, another pattern of neurons is fired but there may be overlap because they are both birthday parties. This kind of remembering is the idea of retrieval because it involves recalling the specific distributed representation created during the encoding of the experience.

Sleep

Some theories consider sleep to be an important factor in establishing well-organized long-term memories. (See also sleep and learning.) Sleep plays a key function in the consolidation of new memories.

According to Tarnow's theory, long-term memories are stored in dream format (reminiscent of Penfield & Rasmussen's findings that electrical excitations of the cortex give rise to experiences similar to dreams). During waking life an executive function interprets LTM consistent with reality checking (Tarnow 2003). It is further proposed in the theory that the information stored in memory, no matter how it was learned, can affect performance on a particular task without the subject being aware that this memory is being used. Newly acquired declarative memory traces are believed to be reactivated during NonREM sleep to promote their hippocampo-neocortical transfer for long-term storage. Specifically, new declarative memories are better remembered if recall follows Stage II non-rapid eye movement sleep. The reactivation of memories during sleep can lead to lasting synaptic changes within certain neural networks. It is the high spindle activity, low oscillation activity, and delta wave activity during NREM sleep that helps to contribute to declarative memory consolidation. In learning before sleep, spindles are redistributed to neuronally active up-states within slow oscillations during NREM sleep. Sleep spindles are thought to induce synaptic changes and thereby contribute to memory consolidation during sleep. Here, we examined the role of sleep in the object-place recognition task, a task closely comparable to tasks typically applied for testing human declarative memory: It is a one-trial task, hippocampus-dependent, not stressful and can be repeated within the same animal. Sleep deprivation reduces vigilance or arousal levels, affecting the efficiency of certain cognitive functions such as learning and memory.

The theory that sleep benefits memory retention is not a new idea. It has been around since Ebbinghaus's experiment on forgetting in 1885. More recently studies have been done by Payne and colleagues and Holtz and colleagues. In Payne and colleague's experiment participants were randomly selected and split into two groups. Both groups were given semantically related or unrelated word pairs, but one group was given the information at 9 A.M. and the other group received theirs at 9 P.M. Participants were then tested on the word pairs at one of three intervals 30 minutes, 12 hours, or 24 hours later. It was found that participants who had a period of sleep between the learning and testing sessions did better on the memory tests. This information is similar to other results found by previous experiments by Jenkins and Dallenbach (1924). It has also been found that many domains of declarative memory are affected by sleep such as emotional memory, semantic memory, and direct encoding.

Holtz found that not only does sleep affect consolidation of declarative memories, but also procedural memories. In this experiment, fifty adolescent participants were taught either word pairs (which represents declarative memory) and a finger tapping task (procedural memory) at one of two different times of day. What they found was that the procedural finger tapping task was best encoded and remembered directly before sleep, but the declarative word pairs task was better remembered and encoded if learned at 3 in the afternoon.

Divisions

The brain does not store memories in one unified structure. Instead, different types of memory are stored in different regions of the brain. LTM is typically divided up into two major headings: explicit memory and implicit memory.

Explicit memory

Explicit memory (or declarative memory) refers to all memories that are consciously available. These are encoded by the hippocampus, entorhinal cortex, and perirhinal cortex, but consolidated and stored elsewhere. The precise location of storage is unknown, but the temporal cortex has been proposed as a likely candidate. Research by Meulemans and Van der Linden (2003) found that amnesiac patients with damage to the medial temporal lobe performed more poorly on explicit learning tests than did healthy controls. However, these same amnesiac patients performed at the same rate as healthy controls on implicit learning tests. This implies that the medial temporal lobe is heavily involved in explicit learning, but not in implicit learning.

Declarative memory has three major subdivisions:

Episodic memory

Episodic memory refers to memory for specific events in time, as well as supporting their formation and retrieval. Some examples of episodic memory would be remembering someone's name and what happened at your last interaction with each other. Experiments conducted by Spaniol and colleagues indicated that older adults have worse episodic memories than younger adults because episodic memory requires context dependent memory. It is said that episodic memories are not as detailed or accurate as people grow older in age. Some people may begin to have issues with identification or presentation related things as they age. They may not be able to recall things from their memory or have as good of a storage for details as they may have been able to do in the past. The Hippocampus is responsible for the functions of episodic memory and research suggests that the use of exercise can be effective in improving brain functions such as the episodic memory. According to Damien Moore and Paul D. Loprinzi, episodic memory can be improved using long-term potentiation, which is when synapses are made to be more durable with exercise. The durability and healthiness of the synapses will in time be able to pick up more connections with neurons and eventually help with episodic memory. Mnemonic training has also been proven to be effective with the sharpening of episodic memory. These trainings include things like the alphabet, music, numerical systems, and other learning systems. Studies by Shuyuan Chen and Zhihui Cai have shown that mnemonic training has shown to be able to improve episodic memory long term.

Semantic memory

Semantic memory refers to knowledge about factual information, such as the meaning of words. Semantic memory is independent information such as information remembered for a test. In contrast with episodic memory, older adults and younger adults do not show much of a difference in semantic memory, presumably because semantic memory does not depend on context memory.

Autobiographical memory

Autobiographical memory refers to knowledge about events and personal experiences from an individual's own life. Autographical memories are facilitated by aids including verbal, face-evoked, picture-evoked, odour-evoked, and music-evoked autobiographical memory cues. Though similar to episodic memory, it differs in that it contains only those experiences which directly pertain to the individual, from across their lifespan. Conway and Pleydell-Pearce (2000) argue that this is one component of the self-memory system.

Implicit memory

Implicit memory (procedural memory) refers to the use of objects or movements of the body, such as how exactly to use a pencil, drive a car, or ride a bicycle. This type of memory is encoded, and it is presumed stored by the striatum and other parts of the basal ganglia. The basal ganglia is believed to mediate procedural memory and other brain structures and is largely independent of the hippocampus. Research by Manelis, Hanson, and Hanson (2011) found that the reactivation of the parietal and occipital regions was associated with implicit memory. Procedural memory is considered non-declarative memory or unconscious memory which includes priming and non-associative learning. The first part of nondeclarative memory (implicit memory) involves priming. Priming occurs when you do something faster after you have already done that activity, such as writing or using a fork. Other categories of memory may also be relevant to the discussion of LTM. For example:

Emotional memory, the memory for events that evoke a particularly strong emotion, is a domain that can involve both declarative and procedural memory processes. Emotional memories are consciously available, but elicit a powerful, unconscious physiological reaction. Research indicates that the amygdala is extremely active during emotional situations and acts with the hippocampus and prefrontal cortex in the encoding and consolidation of emotional events.

Working memory is not part of LTM but is important for it to function. Working memory holds and manipulates information for a short period of time, before it is either forgotten or encoded into LTM. Then, in order to remember something from LTM, it must be brought back into working memory. If working memory is overloaded, it can affect the encoding of LTM. If one has a good working memory, they may have a better LTM encoding.

Disorders of memory

Minor slips and lapses of memory are fairly commonplace and may increase naturally with age, when ill, or under stress. Some women may experience more memory lapses following the onset of the menopause. In general, more serious problems with memory occur due to traumatic brain injury or neurodegenerative disease.

Traumatic brain injury

The majority of findings on memory have been the result of studies that lesioned specific brain regions in rats or primates, but some of the most important work has been the result of accidental or inadvertent brain trauma. The most famous case in recent memory studies is the case study of HM, who had parts of his hippocampus, parahippocampal cortices, and surrounding tissue removed in an attempt to cure his epilepsy. His subsequent total anterograde amnesia and partial retrograde amnesia provided the first evidence for the localization of memory function, and further clarified the differences between declarative and procedural memory.

Neurodegenerative diseases

Many neurodegenerative diseases can cause memory loss. Some of the most prevalent (and, as a consequence, most intensely researched) include Alzheimer's disease, dementia, Huntington's disease, multiple sclerosis, and Parkinson's disease. None act specifically on memory; instead, memory loss is often a casualty of generalized neuronal deterioration. Currently, these illnesses are irreversible, but research into stem cells, psychopharmacology, and genetic engineering holds much promise.

Those with Alzheimer's disease generally display symptoms such as getting momentarily lost on familiar routes, placing possessions in inappropriate locations, and distortions of existing memories or completely forgetting memories. Researchers have often used the Deese–Roediger–McDermott paradigm (DRM) to study the effects of Alzheimer's disease on memory. The DRM paradigm presents a list of words such as doze, pillow, bed, dream, nap, etc., but no theme word is presented. In this case, the theme word would have been "sleep." Alzheimer's disease patients are more likely to recall the theme word as being part of the original list than healthy adults. There is a possible link between longer encoding times and increased false memory in LTM. The patients end up relying on the gist of the information instead of the specific words themselves. Alzheimer's disease leads to an uncontrolled inflammatory response brought on by extensive amyloid deposition in the brain, which leads to cell death in the brain. This gets worse over time and eventually leads to cognitive decline after the loss of memory. Pioglitazone may improve cognitive impairments, including memory loss, and may help protect long-term and visuospatial memory from neurodegenerative diseases.

Parkinson's disease patients have problems with cognitive performance; these issues resemble those seen in frontal lobe patients and can often lead to dementia. It is thought that Parkinson's disease is caused by degradation of the dopaminergic mesocorticolimbic projection originating from the ventral tegmental area. It has also been indicated that the hippocampus plays an important role in episodic and spatial (parts of LTM) memory, and Parkinson's disease patients have abnormal hippocampuses resulting in abnormal LTM functioning. L-dopa injections are often used to try to relieve Parkinson's disease symptoms, as well as behavioral therapy.

Schizophrenia patients have trouble with attention and executive functions, which in turn affects LTM consolidation and retrieval. They cannot encode or retrieve temporal information properly, which causes them to select inappropriate social behaviors. They cannot effectively use the information they possess. The prefrontal cortex, where schizophrenia patients have structural abnormalities, is involved with the temporal lobe and also affects the hippocampus, which causes their difficulty in encoding and retrieving temporal information (including LTM).

Biological underpinnings at the cellular level

Long-term memory, unlike short-term memory, is dependent upon the synthesis of new proteins. This occurs within the cellular body, and concerns the particular transmitters, receptors, and new synapse pathways that reinforce the communicative strength between neurons. The production of new proteins devoted to synapse reinforcement is triggered after the release of certain signaling substances (such as calcium within hippocampal neurons) in the cell. In the case of hippocampal cells, this release is dependent upon the expulsion of magnesium (a binding molecule) that is expelled after significant and repetitive synaptic signaling. The temporary expulsion of magnesium frees NMDA receptors to release calcium in the cell, a signal that leads to gene transcription and the construction of reinforcing proteins. For more information, see long-term potentiation (LTP).

One of the newly synthesized proteins in LTP is also critical for maintaining LTM. This protein is an autonomously active form of the enzyme protein kinase C (PKC), known as PKMζ. PKMζ maintains the activity-dependent enhancement of synaptic strength and inhibiting PKMζ erases established long-term memories, without affecting short-term memory or, once the inhibitor is eliminated, the ability to encode and store new long-term memories is restored.

Also, BDNF is important for the persistence of long-term memories.

The long-term stabilization of synaptic changes is also determined by a parallel increase of pre- and postsynaptic structures such as synaptic boutons, dendritic spines, and postsynaptic density. On the molecular level, an increase of the postsynaptic scaffolding proteins PSD-95 and HOMER1c has been shown to correlate with the stabilization of synaptic enlargement.

The cAMP response element-binding protein (CREB) is a transcription factor which is believed to be important in consolidating short- to long-term memories, and which is believed to be downregulated in Alzheimer's disease.

DNA methylation and demethylation

Rats exposed to an intense learning event may retain a life-long memory of the event, even after a single training session. The LTM of such an event appears to be initially stored in the hippocampus, but this storage is transient. Much of the long-term storage of the memory seems to take place in the anterior cingulate cortex. When such an exposure was experimentally applied, more than 5,000 differently methylated DNA regions appeared in the hippocampus neuronal genome of the rats at one and at 24 hours after training. These alterations in methylation pattern occurred at many genes that were down-regulated, often due to the formation of new 5-methylcytosine sites in CpG rich regions of the genome. Furthermore, many other genes were upregulated, likely often due to hypomethylation. Hypomethylation often results from the removal of methyl groups from previously existing 5-methylcytosines in DNA. Demethylation is carried out by several proteins acting in concert, including TET enzymes as well as enzymes of the DNA base excision repair pathway (see Epigenetics in learning and memory). The pattern of induced and repressed genes in brain neurons subsequent to an intense learning event likely provides the molecular basis for a LTM of the event.

Contradictory evidence

A couple of studies have had results that contradict the dual-store memory model. Studies showed that in spite of using distractors, there was still both a recency effect for a list of items and a contiguity effect.

Another study revealed that how long an item spends in short-term memory is not the key determinant in its strength in long-term memory. Instead, whether the participant actively tries to remember the item while elaborating on its meaning determines the strength of its store in LTM.

Single-store memory model

An alternative theory is that there is only one memory store with associations among items and their contexts. In this model, the context serves as a cue for retrieval, and the recency effect is greatly caused by the factor of context. Immediate and delayed free recall will have the same recency effect because the relative similarity of the contexts still exists. Also, the contiguity effect still occurs because contiguity also exists between similar contexts.

Operator (computer programming)

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