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Friday, March 10, 2023

Outline of science

From Wikipedia, the free encyclopedia

The following outline is provided as a topical overview of science; the discipline of science is defined as both the systematic effort of acquiring knowledge through observation, experimentation and reasoning, and the body of knowledge thus acquired, the word "science" derives from the Latin word scientia meaning knowledge. A practitioner of science is called a "scientist". Modern science respects objective logical reasoning, and follows a set of core procedures or rules to determine the nature and underlying natural laws of all things, with a scope encompassing the entire universe. These procedures, or rules, are known as the scientific method.

Essence of science

  • Research – systematic investigation into existing or new knowledge.
  • Scientific discovery – observation of new phenomena, new actions, or new events and providing new reasoning to explain the knowledge gathered through such observations with previously acquired knowledge from abstract thought and everyday experiences.
  • Laboratory – facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed.
  • Objectivity – the idea that scientists, in attempting to uncover truths about the natural world, must aspire to eliminate personal or cognitive biases, a priori commitments, emotional involvement, etc.
  • Inquiry – any process that has the aim of augmenting knowledge, resolving doubt, or solving a problem.

Scientific method

Scientific method   (outline) – body of techniques for investigating phenomena and acquiring new knowledge, as well as for correcting and integrating previous knowledge. It is based on observable, empirical, measurable evidence, and subject to laws of reasoning, both deductive and inductive.

  • Empirical method
  • Experimental method – The steps involved to produce a reliable and logical conclusion include:
    1. Conducting initial research and asking a question about a natural phenomenon
    2. Making observations of the phenomenon and/or collecting data about it
    3. Forming a hypothesis – proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous observations that cannot satisfactorily be explained with the available scientific theories.
    4. Predicting a logical consequence of the hypothesis
    5. Testing the hypothesis through an experiment – methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. The 3 types of scientific experiments are:
      • Controlled experiment – experiment that compares the results obtained from an experimental sample against a control sample, which is practically identical to the experimental sample except for the one aspect the effect of which is being tested (the independent variable).
      • Natural experiment – empirical study in which the experimental conditions (i.e., which units receive which treatment) are determined by nature or by other factors out of the control of the experimenters and yet the treatment assignment process is arguably exogenous. Thus, natural experiments are observational studies and are not controlled in the traditional sense of a randomized experiment.
        • Observational study – draws inferences about the possible effect of a treatment on subjects, where the assignment of subjects into a treated group versus a control group is outside the control of the investigator.
      • Field experiment – applies the scientific method to experimentally examine an intervention in the real world (or as many experimentalists like to say, naturally occurring environments) rather than in the laboratory. See also field research.
    6. Gather and analyze data from experiments or observations, including indicators of uncertainty.
    7. Draw conclusions by comparing data with predictions. Possible outcomes:
      • Conclusive:
        • The hypothesis is falsified by the data.
        • Data are consistent with the hypothesis.
        • Data are consistent with alternative hypotheses.
      • Inconclusive:
        • Data are not relevant to the hypothesis, or data and predictions are incommensurate.
        • There is too much uncertainty in the data to draw any conclusion.
    8. Further steps include peer review and enabling others to reproduce or falsify the observations and/or conclusions
  • Deductive-nomological model
  • Scientific modelling
  • Models of scientific method
    • Hypothetico-deductive model – proposed description of scientific method. According to it, scientific inquiry proceeds by formulating a hypothesis in a form that could conceivably be falsified by a test on observable data. A test that could and does run contrary to predictions of the hypothesis is taken as a falsification of the hypothesis. A test that could but does not run contrary to the hypothesis corroborates the theory.

Branches of science

Branches of science – divisions within science with respect to the entity or system concerned, which typically embodies its own terminology and nomenclature. The most traditional data structure used for organizing the subfields of science is the "tree of knowledge", hence the idea of different scientific "branches". But over time, several other taxonomic systems have also been proposed for that purpose (such as networks, tables or circular schemes).

Formal science

Formal science – branches of knowledge that are concerned with formal systems, such as those under the branches of: logic, mathematics, computer science, statistics, and some aspects of linguistics. Unlike other sciences, the formal sciences are not concerned with the validity of theories based on observations in the real world, but instead with the properties of formal systems based on definitions and rules.

Natural science

Natural science   (outline) – a major branch of science that tries to explain and predict nature's phenomena, based on empirical evidence. In natural science, hypotheses must be verified scientifically to be regarded as scientific theory. Validity, accuracy, and social mechanisms ensuring quality control, such as peer review and repeatability of findings, are among the criteria and methods used for this purpose. Natural science can be broken into two main branches: biology and physical science. Each of these branches, and all of their sub-branches, are referred to as natural sciences.

Social science

Social science – study of the social world constructed between humans. The social sciences usually limit themselves to an anthropomorphically centric view of these interactions with minimal emphasis on the inadvertent impact of social human behavior on the external environment (physical, biological, ecological, etc.). 'Social' is the concept of exchange/influence of ideas, thoughts, and relationship interactions (resulting in harmony, peace, self enrichment, favoritism, maliciousness, justice seeking, etc.) between humans. The scientific method is used in many social sciences, albeit adapted to the needs of the social construct being studied.

Applied science

Applied science – branch of science that applies existing scientific knowledge to develop more practical applications, including inventions and other technological advancements.

Essence science

Essence science – is a science that discusses problems ranging from general and core questions to major scientific problems in both social and natural sciences, among other things. Philosophy is an example of an essential science that can be classified as a subset of it.

Types of scientific fields

  • Exact science – any field of science capable of accurate quantitative expression or precise predictions and rigorous methods of testing hypotheses, especially reproducible experiments involving quantifiable predictions and measurements.
  • Fundamental science – science that describes the most basic objects, forces, relations between them and laws governing them, such that all other phenomena may be in principle derived from them following the logic of scientific reductionism.
  • Hard and soft science – colloquial terms often used when comparing scientific fields of academic research or scholarship, with hard meaning perceived as being more scientific, rigorous, or accurate.

Politics of science

  • Disruptive technology – innovation that helps create a new market and value network, and eventually goes on to disrupt an existing market and value network (over a few years or decades), displacing an earlier technology.
  • Kansas evolution hearings – series of hearings held in Topeka, Kansas, United States 5 to 12 May 2005 by the Kansas State Board of Education and its State Board Science Hearing Committee to change how evolution and the origin of life would be taught in the state's public high school science classes.
  • List of books about the politics of science – list of books about the politics of science.
  • Politicization of science – politicization of science is the manipulation of science for political gain.
  • Science by press release – refers to scientists who put an unusual focus on publicizing results of research in the media.

History of science

  • History of science – history of science in general
    • History of scientific method – history of scientific method is a history of the methodology of scientific inquiry, as differentiated from a history of science in general.
    • Theories/sociology of science – sociology and philosophy of science, as well as the entire field of science studies, have in the 20th century been occupied with the question of large-scale patterns and trends in the development of science, and asking questions about how science "works" both in a philosophical and practical sense.
    • Historiography – study of the history and methodology of the sub-discipline of history, known as the history of science, including its disciplinary aspects and practices (methods, theories, schools) and to the study of its own historical development ("History of History of Science", i.e., the history of the discipline called History of Science).
    • History of pseudoscience – history of pseudoscience is the study of pseudoscientific theories over time. A pseudoscience is a set of ideas that presents itself as science, while it does not meet the criteria to properly be called such.
    • Timeline of scientific discoveries – shows the date of publication of major scientific theories and discoveries, along with the discoverer. In many cases, the discoveries spanned several years.
    • Timeline of scientific thought – lists the major landmarks across all scientific philosophy and methodological sciences.

By period

  • History of science in early cultures – history of science in early cultures refers to the study of protoscience in ancient history, prior to the development of science in the Middle Ages.
  • History of science in Classical Antiquity – history of science in classical antiquity encompasses both those inquiries into the workings of the universe aimed at such practical goals as establishing a reliable calendar or determining how to cure a variety of illnesses and those abstract investigations known as natural philosophy.
  • History of science in the Middle Ages – Science in the Middle Ages comprised the study of nature, including practical disciplines, the mathematics and natural philosophy in medieval Europe.
  • History of science in the Renaissance – During the Renaissance, great advances occurred in geography, astronomy, chemistry, physics, mathematics, manufacturing, and engineering.
  • Scientific revolution – scientific revolution is an era associated primarily with the 16th and 17th centuries during which new ideas and knowledge in physics, astronomy, biology, medicine and chemistry transformed medieval and ancient views of nature and laid the foundations for modern science.
  • Governmental impact on science during WWII – Governmental impact on science during World War II represents the effect of public administration on technological development that provided many advantages to the armed forces, economies and societies in their strategies during the war.

By date

By field

By region

History of science in present states, by continent

See – Category:Science and technology by continent

History of science in historic states

Philosophy of science

Adoption, use, results and coordination of science

Technology and mechanisms of science

Scientific community

Scientific organizations

Scientists

  • Scientist – practitioner of science; an individual who uses scientific method to objectively inquire into the nature of reality—be it the fundamental laws of physics or how people behave. There are many names for scientists, often named in relation to the job that they do. One example of this is a biologist, a scientist who studies biology (the study of living organisms and their environments).

Types of scientist

By field

The scientific fields mentioned below are generally described by the science they study.

  • Agricultural scientist – broad multidisciplinary field that encompasses the parts of exact, natural, economic and social sciences that are used in the practice and understanding of agriculture.
  • Archaeologist – study of human activity, primarily through the recovery and analysis of the material culture and environmental data that they have left behind, which includes artifacts, architecture, biofacts and cultural landscapes (the archaeological record).
  • Astronomer – astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.
    • Astrophysicist – branch of astronomy that deals with the physics of the universe, including the physical properties of celestial objects, as well as their interactions and behavior.
  • Biologist – scientist devoted to the study of living organisms and their relationship to their environment.
    • Astrobiologist – study of the origin, evolution, distribution, and future of extraterrestrial life.
    • Biophysicist – interdisciplinary science that uses the methods of physical science to study biological systems.
    • Biotechnologist – field of applied biology that involves the use of living organisms and bioprocesses in engineering, technology, medicine and other fields requiring bioproducts.
    • Botanist – discipline of biology, is the science of plant life.
    • Cognitive scientists – scientific study of the mind and its processes.
    • Ecologist – scientific study of the relations that living organisms have with respect to each other and their natural environment.
    • Entomologist – scientific study of insects, a branch of arthropodology.
    • Evolutionary biologist – sub-field of biology concerned with the study of the evolutionary processes that have given rise to the diversity of life on Earth.
    • Geneticist – biologist who studies genetics, the science of genes, heredity, and variation of organisms.
    • Herpetologist – branch of zoology concerned with the study of amphibians (including frogs, toads, salamanders, newts, and gymnophiona) and reptiles (including snakes, lizards, amphibians, turtles, terrapins, tortoises, crocodiles, and the tarantulas).
    • Immunologist – branch of biomedical science that covers the study of all aspects of the immune system in all organisms.
    • Ichthyologist – study of fish.
    • Lepidopterist – person who specializes in the study of Lepidoptera, members of an order encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies.
    • Marine biologist – scientific study of organisms in the ocean or other marine or brackish bodies of water.
    • Medical scientist – basic research, applied research, or translational research conducted to aid and support the body of knowledge in the field of medicine.
    • Microbiologist – study of microscopic organisms.
    • Mycologist – branch of biology concerned with the study of fungi, including their genetic and biochemical properties, their taxonomy and their use to humans as a source for tinder, medicinals (e.g., penicillin), food (e.g., beer, wine, cheese, edible mushrooms) and entheogens, as well as their dangers, such as poisoning or infection.
    • Neuroscientist – individual who studies the scientific field of neuroscience or any of its related sub-fields.
    • Ornithologist – branch of zoology that concerns the study of birds.
    • Paleontologist – study of prehistoric life.
    • Pathologist – precise study and diagnosis of disease.
    • Pharmacologist – branch of medicine and biology concerned with the study of drug action.
    • Physiologist – science of the function of living systems.
    • Zoologist – branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct.
  • Chemist – scientist trained in the study of chemistry.
    • Analytical chemist – study of the separation, identification, and quantification of the chemical components of natural and artificial materials.
    • Biochemist – study of chemical processes in living organisms, including, but not limited to, living matter.
    • Inorganic chemist – branch of chemistry concerned with the properties and behavior of inorganic compounds.
    • Organic chemist – subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation (by synthesis or by other means) of carbon-based compounds, hydrocarbons, and their derivatives.
    • Physical chemist – study of macroscopic, atomic, subatomic, and particulate phenomena in chemical systems in terms of physical laws and concepts.
  • Earth scientist – all-embracing term for the sciences related to the planet Earth.
    • Geologist – scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes and history that has shaped it.
    • Glaciologist – study of glaciers, or more generally ice and natural phenomena that involve ice.
    • Hydrologist – study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability.
    • Limnologist – study of inland waters
    • Meteorologist – study of weather
    • Mineralogist – study of chemistry, crystal structure, and physical (including optical) properties of minerals.
    • Oceanographer – branch of Earth science that studies the ocean
    • Paleontologist – study of prehistoric life
    • Seismologist – scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies.
    • Volcanologist – study of volcanoes, lava, magma, and related geological, geophysical and geochemical phenomena.
  • Informatician – science of information, the practice of information processing, and the engineering of information systems.
    • Computer scientist – scientist who has acquired knowledge of computer science, the study of the theoretical foundations of information and computation
  • Library scientist – interdisciplinary or multidisciplinary field that applies the practices, perspectives, and tools of management, information technology, education, and other areas to libraries; the collection, organization, preservation, and dissemination of information resources; and the political economy of information.
  • Management scientist – study of advanced analytical methods to help make better decisions.
  • Mathematician– person with an extensive knowledge of mathematics, a field that has been informally defined as being concerned with numbers, data, collection, quantity, structure, space, and change.
    • Statistician – someone who works with theoretical or applied statistics.
  • Military scientist – process of translating national defense policy to produce military capability by employing military scientists, including theorists, researchers, experimental scientists, applied scientists, designers, engineers, test technicians, and military personnel responsible for prototyping.
  • Physicist – scientist who does research in physics
  • Psychologist – professional or academic title used by individuals who practice psychology
    • Abnormal psychologist – branch of psychology that studies unusual patterns of behavior, emotion and thought, which may or may not be understood as precipitating a mental disorder.
    • Educational psychologist – psychologist whose differentiating functions may include diagnostic and psycho-educational assessment, psychological counseling in educational communities (students, teachers, parents and academic authorities), community-type psycho-educational intervention, and mediation, coordination, and referral to other professionals, at all levels of the educational system.
    • Biopsychologist – application of the principles of biology (in particular neurobiology), to the study of physiological, genetic, and developmental mechanisms of behavior in human and non-human animals.
    • Clinical psychologist – integration of science, theory and clinical knowledge for the purpose of understanding, preventing, and relieving psychologically based distress or dysfunction and to promote subjective well-being and personal development.
    • Comparative psychologist – scientific study of the behavior and mental processes of non-human animals, especially as these relate to the phylogenetic history, adaptive significance, and development of behavior.
    • Cognitive psychologist – subdiscipline of psychology exploring internal mental processes. It is the study of how people perceive, remember, think, speak, and solve problems.
    • Developmental psychologist – scientific study of systematic psychological changes, emotional changes, and perception changes that occur in human beings over the course of their life span.
    • Evolutionary psychologist – approach in the social and natural sciences that examines psychological traits such as memory, perception, and language from a modern evolutionary perspective.
    • Experimental psychologist – study of behavior and the processes that underlie it, by means of experiment
    • Neuropsychologist – studies the structure and function of the brain as they relate to specific psychological processes and behaviors.
    • Social psychologist – scientific study of how people's thoughts, feelings, and behaviors are influenced by the actual, imagined, or implied presence of others.
  • Social scientist – field of study concerned with society and human behaviors.
    • Anthropologist – study of humanity.
      • Ethnologist – branch of anthropology that compares and analyzes the origins, distribution, technology, religion, language, and social structure of the ethnic, racial, and/or national divisions of humanity.
    • Communication scientist – academic field that deals with processes of human communication, commonly defined as the sharing of symbols to create meaning.
    • Criminologist – study of criminal behavior
    • Demographer – statistical study of populations
    • Economist – professional in the social science discipline of economics.
    • Geographer – geographer is a scholar whose area of study is geography, the study of Earth's natural environment and human society.
    • Political economist – study of production, buying, and selling, and their relations with law, custom, and government, as well as with the distribution of national income and wealth, including through the budget process.
    • Political scientist – social science discipline concerned with the study of the state, government, and politics.
    • Sociologist
  • Technologist
By employment status
  • Academic – community of students and scholars engaged in higher education and research.
  • Corporate Scientist – someone who is employed by a business to do research and development for the benefit of that business
  • Layperson – someone who is not an expert or someone who has not had professional training
  • Gentleman scientist – financially independent scientist who pursues scientific study as a hobby.
  • Government scientist – scientist employed by a country's government

Famous scientists

  • Aristotle – Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great
  • Archimedes – Greek mathematician, physicist, engineer, inventor, and astronomer
  • Andreas Vesalius – Flemish anatomist, physician, and author of one of the most influential books on human anatomy, De humani corporis fabrica (On the Structure of the Human Body)
  • Nicolaus Copernicus – Renaissance astronomer and the first person to formulate a comprehensive heliocentric cosmology which displaced the Earth from the center of the universe
  • Galileo Galilei – Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution
  • Johannes Kepler – German mathematician, astronomer and astrologer. A key figure in the 17th century scientific revolution, he is best known for his eponymous laws of planetary motion, codified by later astronomers, based on his works Astronomia nova, Harmonices Mundi, and Epitome of Copernican Astronomy
  • René Descartes – French philosopher, mathematician, and writer who spent most of his adult life in the Dutch Republic
  • Isaac Newton – English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived"
  • Leonhard Euler – pioneering Swiss mathematician and physicist
  • Pierre-Simon Laplace – French mathematician and astronomer whose work was pivotal to the development of mathematical astronomy and statistics
  • Alexander von Humboldt – German geographer, naturalist and explorer, and the younger brother of the Prussian minister, philosopher and linguist Wilhelm von Humboldt
  • Charles Darwin – English naturalist, he established that all species of life have descended over time from common ancestors, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection
  • James Clerk Maxwell – Scottish physicist and mathematician
  • Marie Curie – Polish physicist and chemist famous for her pioneering research on radioactivity
  • Albert Einstein – German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics
  • Linus Pauling – American chemist, biochemist, peace activist, author, and educator. He was one of the most influential chemists in history and ranks among the most important scientists of the 20th century
  • John Bardeen – American physicist and electrical engineer, the only person to have won the Nobel Prize in Physics twice
  • Frederick Sanger – English biochemist and a two-time Nobel laureate in chemistry, the only person to have been so
  • Stephen Hawking – British theoretical physicist, cosmologist, and author

Science education

Science education

  • Scientific literacy – encompasses written, numerical, and digital literacy as they pertain to understanding science, its methodology, observations, and theories.
  • Pseudo-scholarship – is a work (e.g., publication, lecture) or body of work that is presented as, but is not, the product of rigorous and objective study or research; the act of producing such work; or the pretended learning upon which it is based.

  • Science communication

Mental rotation

From Wikipedia, the free encyclopedia
 
Example problem based on Shepard & Metzlar's "Mental Rotation Task": are these two three-dimensional shapes identical when rotated?

Mental rotation is the ability to rotate mental representations of two-dimensional and three-dimensional objects as it is related to the visual representation of such rotation within the human mind. There is a relationship between areas of the brain associated with perception and mental rotation. There could also be a relationship between the cognitive rate of spatial processing, general intelligence and mental rotation.

Mental rotation can be described as the brain moving objects in order to help understand what they are and where they belong. Mental rotation has been studied to try to figure out how the mind recognizes objects in their environment. Researchers generally call such objects stimuli. Mental rotation is one cognitive function for the person to figure out what the altered object is.

Mental rotation can be separated into the following cognitive stages:

  1. Create a mental image of an object from all directions (imagining where it continues straight vs. turns).
  2. Rotate the object mentally until a comparison can be made (orientating the stimulus to other figure).
  3. Make the comparison.
  4. Decide if the objects are the same or not.
  5. Report the decision (reaction time is recorded when a lever is pulled or a button is pressed).

Assessment

Originally developed in 1978 by Vandenberg and Kuse based on the research by Shepherd and Metzler (1971), a Mental Rotation Test (MRT) consists of a participant comparing two 3D objects (or letters), often rotated in some axis, and states if they are the same image or if they are mirror images (enantiomorphs). Commonly, the test will have pairs of images each rotated a specific number of degrees (e.g. 0°, 60°, 120° or 180°). A set number of pairs will be split between being the same image rotated, while others are mirrored. The researcher judges the participant on how accurately and rapidly they can distinguish between the mirrored and non-mirrored pairs.

Notable research

Shepard and Metzler (1971)

Roger Shepard and Jacqueline Metzler (1971) were some of the first to research the phenomenon. Their experiment specifically tested mental rotation on three-dimensional objects. Each subject was presented with multiple pairs of three-dimensional, asymmetrical lined or cubed objects. The experiment was designed to measure how long it would take each subject to determine whether the pair of objects were indeed the same object or two different objects. Their research showed that the reaction time for participants to decide if the pair of items matched or not was linearly proportional to the angle of rotation from the original position. That is, the more an object has been rotated from the original, the longer it takes an individual to determine if the two images are of the same object or enantiomorphs.

Vandenberg and Kuse (1978)

In 1978, Steven G. Vandenberg and Allan R. Kuse developed the Mental Rotations Test (MRT) to assess mental rotation abilities that was based on Shepard and Metzler's (1971) original study. The Mental Rotations Test was constructed using India ink drawings. Each stimulus was a two-dimensional image of a three-dimensional object drawn by a computer. The image was then displayed on an oscilloscope. Each image was then shown at different orientations rotated around the vertical axis. The original test contained 20 items, demanding the comparison of four figures with a criterion figure, with two of them being correct. Following the basic ideas of Shepard and Metzler's experiment, this study found a significant difference in the mental rotation scores between men and women, with men performing better. Correlations with other measures showed strong association with tests of spatial visualization and no association with verbal ability.

Neuropsychology of Mental Rotation

In 2000, a study was conducted to find out which part of the brain is activated during mental rotation. Seven volunteers (four males and three females) between the ages of twenty-nine to sixty-six participated in this experiment. For the study, the subjects were shown eight characters 4 times each (twice in normal orientation and twice reversed) and the subjects had to decide if the character was in its normal configuration or if it was the mirror image. During this task, a PET scan was performed and revealed activation in the right posterior parietal lobe.

Functional magnetic resonance imaging (fMRI) studies of brain activation during mental rotation reveal consistent increased activation of the parietal lobe, specifically the inter-parietal sulcus, that is dependent on the difficulty of the task. In general, the larger the angle of rotation, the more brain activity associated with the task. This increased brain activation is accompanied by longer times to complete the rotation task and higher error rates. Researchers have argued that the increased brain activation, increased time, and increased error rates indicate that task difficulty is proportional to the angle of rotation.

A 2006 study observed the following brain areas to be activated during mental rotation as compared to baseline: bilateral medial temporal gyrus, left medial occipital gyrus, bilateral superior occipital gyrus, bilateral superior parietal lobe, and left inferior occipital gyrus during the rotation task.

Development of Mental Rotation

A study from 2008 suggested that differences may occur early during development. The experiment was done on 3- to 4-month-old infants using a 2D mental rotation task. They used a preference apparatus that consists of observing during how much time the infant is looking at the stimulus. They started by familiarizing the participants with the number "1" and its rotations. Then they showed them a picture of a "1" rotated and its mirror image. It appears that gendered differences may appear early in development, as the study showed that males are more responsive to the mirror image. According to the study, this may mean that males and females process mental rotation differently even as infants. Supporting the presence of such differences early in development, other studies have found that gendered differences in mental rotation tests were visible in all age groups, including young children. Interestingly, these differences emerged much later for other categories of spatial tests.

In 2020, Advances in Childhood Development and Behavior examined mental rotation abilities during very early development. They discovered that an ability to mentally rotate objects can be detected in infants as young as 3 months of age. Also, MR processes in infancy likely remain stable over time into adulthood, indicating an innate, static component to human conception of MR. Additional variables that appeared to influence infants' MR performance include motor activity, stimulus complexity, hormone levels, and parental attitudes.

Factors that Affect Mental Rotation Performance

Rotation in depth 90 degrees
 
Rotation in the picture plane 90 degrees

Color

Physical objects that people imagine rotating in everyday life have many properties, such as textures, shapes, and colors. A study at the University of California Santa Barbara was conducted to specifically test the extent to which visual information, such as color, is represented during mental rotation. This study used several methods such as reaction time studies, verbal protocol analysis, and eye tracking. In the initial reaction time experiments, those with poor rotational ability were affected by the colors of the image, whereas those with good rotational ability were not. Overall, those with poor ability were faster and more accurate identifying images that were consistently colored. The verbal protocol analysis showed that the subjects with low spatial ability mentioned color in their mental rotation tasks more often than participants with high spatial ability. One thing that can be shown through this experiment is that those with higher rotational ability will be less likely to represent color in their mental rotation. Poor rotators will be more likely to represent color in their mental rotation using piecemeal strategies (Khooshabeh & Hegarty, 2008).

Athletic, Musical, and Artistic Skills

Research on how athleticism and artistic ability affect mental rotation has been conducted. Pietsch, S., & Jansen, P. (2012) showed that people who were athletes or musicians had faster reaction times than people who were not. They tested this by splitting people from the age of 18 and higher into three groups. The groups consisted of music students, sports students, and education students. It was found that students who were focused on sports or music did much better than those who were education majors. Also, it was found that the male athletes and education majors in the experiment were faster than the respective females, but male and female musicians showed no significant difference in reaction time.

A 2007 study supported the results that musicians perform better on mental rotation tasks than non-musicians. In particular, orchestral musicians' MRT task performance exhibited aptitude levels significantly higher than the population baseline.

Moreau, D., Clerc, et al. (2012) also investigated if athletes were more spatially aware than non-athletes. This experiment took undergraduate college students and tested them with the mental rotation test before any sport training, and then again afterward. The participants were trained in two different sports to see if this would help their spatial awareness. It was found that the participants did better on the mental rotation test after they had trained in the sports, than they did before the training. This experiment brought to the research that if people could find ways to train their mental rotation skills they could perform better in high context activities with greater ease.

Researchers studied the difference in mental rotation ability between gymnasts, handball, and soccer players with both in-depth and in-plane rotations. Results suggested that athletes were better at performing mental rotation tasks that were more closely related to their sport of expertise.

There is a correlation in mental rotation and motor ability in children, and this connection is especially strong in boys ages 7–8. The study showed that there is considerable overlap between spatial reasoning and athletic ability, even among young children.

A mental rotation test (MRT) was carried out on gymnasts, orienteers, runners, and non athletes. Results showed that non athletes were greatly outperformed by gymnasts and orienteers, but not runners. Gymnasts (egocentric athletes) did not outperform orienteers (allocentric athletes). Egocentric indicates understanding the position of your body as it relates to objects in space, and allocentric indicates understanding the relation of multiple objects in space independently of the self-perspective.

A study investigated the effect of mental rotation on postural stability. Participants performed a MR (mental rotation) task involving either foot stimuli, hand stimuli, or non-body stimuli (a car) and then had to balance on one foot. The results suggested that MR tasks involving foot stimuli were more effective at improving balance than hand or car stimuli, even after 60 minutes.

Contrary to what one might expect, previous studies examining whether artists are superior at mental rotation have been mixed, and a recent study substantiates the null findings. It has been theorized that artists are adept at recognizing, creating, and activating visual stimuli, but not necessarily at manipulating them.

A 2018 study examined the effect of studying various subjects within higher education on mental rotation ability. The researchers found that architecture students performed significantly better than art students, who performed significantly better than both psychology and business majors, with gender and other demographic differences accounted for. These findings make sense intuitively, given that architecture students are highly acquainted with manipulating the orientation of structures in space.

Sex

Following the Vandenberg and Kuse study, subsequent research attempted to assess the presence of gendered differences in mental rotation ability. For the first couple of decades immediately following the research, the topic was addressed in different meta-analyses with inconclusive results. However, Voyer et al. conducted a comprehensive review in 1995, which showed that gender differences were reliable and more pronounced in specific tasks, indicating that sex affects the processes underlying performance in spatial memory tests. Analogous to other types of spatial reasoning tasks, men tended to outperform women by a statistically significant margin among the MR literature.

As mentioned above, many studies have shown that there is a difference between male and female performance in mental rotation tasks. To learn more about this difference, brain activation during a mental rotation task was studied. In 2012, a study was done.in which males and females were asked to execute a mental rotation task, and their brain activity was recorded with an fMRI. The researchers found a difference of brain activation: males presented a stronger activity in the area of the brain used in a mental rotation task.

Furthermore, sex-related differences in mental rotation abilities may reflect evolutionary differences. Men assumed the role of hunting and foraging, which necessitates a greater degree of visual-spatial processing than the child-rearing and domestic tasks which women performed. Biologically, males receive higher fetal exposure to androgens than females, and retain these relatively higher levels for life. This difference plays a significant role in human sexual dimorphism, and may be a causal factor in the differences observed regarding mental rotation. Interestingly, women with congenital adrenal hyperplasia (CAH), who are exposed to higher levels of fetal androgen than control women, tend to perform better on the MRT than women with normal amounts of fetal androgen exposure. Additionally, the significant role of hormonal variation between the sexes was supported by a 2004 study, which revealed that testosterone (a principal androgen) level in young men was negatively correlated with the number of errors and response time in the MRT. Therefore, higher levels of testosterone probably contribute to better performance.

Another study from 2015 was focused on women and their abilities in a mental rotation task and an emotion recognition task. In this experiment they induced a feeling or a situation in which women feel more powerful or less powerful. They were able to conclude that women in a situation of power are better in a mental rotation task (but less performant in an emotion recognition task) than other women. Interestingly, the types of cognitive strategies that men and women typically employ may be a contributing factor. The literature has established that men generally prefer holistic strategies, whereas women prefer analytic-verbal strategies and focus on specific parts of the whole puzzle. Women tended to act more conservatively as well, sacrificing time to double-check the incorrect items more often than men. Consequently, women require more time to execute their technique when completing tasks like the MRT. In order to determine the extent of this variable's significance, Hirnstein et al. (2009) created a modified MRT in which the number of matching figures could vary between zero and four, which, compared to the original MRT, favored the strategy most often employed by women. The research found that gender differences declined somewhat, but men still outperformed women.

Along the same lines, a 2021 study found intriguing results in an attempt to discern the mechanisms behind the established gender disparity. The researchers hypothesized that task characteristics, not only anatomical or social differences, could explain men’s advantage in mental rotation. In particular, the objects to be rotated were changed from the typical geometric or spherical shapes to male or female stereotyped objects, such as a tractor and a stroller, respectively. The results revealed significant gender differences only when male-stereotyped objects were used as rotational material. When female-stereotyped rotational material was used, men and women performed equally. This finding may explain underlying causes behind the usual disparate outcomes, in that the male ability to do somewhat better on MRT tests probably stems from the evolutionary applicability of spatial reasoning. Objects that aren't relevant to historical male gender roles, and are consequently generally unfamiliar to men, are much more difficult for men to conceptualize spatially than more familiar shapes. Likewise, other recent studies suggest that difference between Mental rotation cognition task are a consequence of procedure and artificiality of the stimuli. A 2017 study leveraged photographs and three-dimensional models, evaluating multiple approaches and stimuli. Results show that changing the stimuli can eliminate any male advantages found from the Vandenberg and Kuse test (1978). 

Studying differences between male and female brains can have interesting applications. For example, it could help in the understanding of the autism spectrum disorders. One of the theories concerning autism is the EMB (extreme male brain). This theory considers autistic people to have an "extreme male brain". In a study from 2015, researchers confirmed that there is a difference between male and female in mental rotation task (by studying people without autism): males are more successful. Then they highlighted the fact that autistic people do not have this "male performance" in a mental rotation task. They conclude their study by "autistic people do not have an extreme version of a male cognitive profile as proposed by the EMB theory".

Current and Future Research Directions

Much of the current and future research directions pertain to expanding on what has been established by the literature and investigating underlying causes behind previous results. Future studies will consider additional factors that could influence MR ability, including demographics, various aptitudes, personality, rare/deviant psychological profiles, among others. Many current and future studies are and will be examining the ways that certain brain abnormalities, including many of those caused by traumatic injuries, affect one's ability to perform mental rotation.

There may be relationships between competent bodily movement and the speed with which individuals can perform mental rotation. Researchers found children who trained with mental rotation tasks had improved strategy skills after practicing. People use many different strategies to complete tasks; psychologists will study participants who use specific cognitive skills to compare competency and reaction times. Others will continue to examine the differences in competency of mental rotation based on the objects being rotated. Participants' identification with the object could hinder or help their mental rotation abilities across gender and ages to support the earlier claim that males have faster reaction times. Psychologists will continue to test similarities between mental rotation and physical rotation, examining the difference in reaction times and relevance to environmental implications.

Mental image

From Wikipedia, the free encyclopedia
 
Visual space is the experience of space by an aware observer. It is the subjective counterpart of the space of physical objects. There is a long history in philosophy, and later psychology of writings describing visual space, and its relationship to the space of physical objects. A partial list would include René Descartes, Immanuel Kant, Hermann von Helmholtz, William James, to name just a few.

A mental image is an experience that, on most occasions, significantly resembles the experience of 'perceiving' some object, event, or scene, but occurs when the relevant object, event, or scene is not actually present to the senses. There are sometimes episodes, particularly on falling asleep (hypnagogic imagery) and waking up (hypnopompic imagery), when the mental imagery may be dynamic, phantasmagoric and involuntary in character, repeatedly presenting identifiable objects or actions, spilling over from waking events, or defying perception, presenting a kaleidoscopic field, in which no distinct object can be discerned. Mental imagery can sometimes produce the same effects as would be produced by the behavior or experience imagined.

The nature of these experiences, what makes them possible, and their function (if any) have long been subjects of research and controversy in philosophy, psychology, cognitive science, and, more recently, neuroscience. As contemporary researchers use the expression, mental images or imagery can comprise information from any source of sensory input; one may experience auditory images, olfactory images, and so forth. However, the majority of philosophical and scientific investigations of the topic focus upon visual mental imagery. It has sometimes been assumed that, like humans, some types of animals are capable of experiencing mental images. Due to the fundamentally introspective nature of the phenomenon, it has been difficult to assess whether or not non-human animals experience mental imagery.

Philosophers such as George Berkeley and David Hume, and early experimental psychologists such as Wilhelm Wundt and William James, understood ideas in general to be mental images. Today it is very widely believed that much imagery functions as mental representations (or mental models), playing an important role in memory and thinking. William Brant (2013, p. 12) traces the scientific use of the phrase "mental images" back to John Tyndall's 1870 speech called the "Scientific Use of the Imagination". Some have suggested that images are best understood to be, by definition, a form of inner, mental or neural representation. Others reject the view that the image experience may be identical with (or directly caused by) any such representation in the mind or the brain, but do not take account of the non-representational forms of imagery.

Mind's eye

The notion of a "mind's eye" goes back at least to Cicero's reference to mentis oculi during his discussion of the orator's appropriate use of simile.

In this discussion, Cicero observed that allusions to "the Syrtis of his patrimony" and "the Charybdis of his possessions" involved similes that were "too far-fetched"; and he advised the orator to, instead, just speak of "the rock" and "the gulf" (respectively)—on the grounds that "the eyes of the mind are more easily directed to those objects which we have seen, than to those which we have only heard".

The concept of "the mind's eye" first appeared in English in Chaucer's (c. 1387) Man of Law's Tale in his Canterbury Tales, where he tells us that one of the three men dwelling in a castle was blind, and could only see with "the eyes of his mind"; namely, those eyes "with which all men see after they have become blind".

Physical basis

The biological foundation of mental imagery is not fully understood. Studies using fMRI have shown that the lateral geniculate nucleus and the V1 area of the visual cortex are activated during mental imagery tasks. Ratey writes:

The visual pathway is not a one-way street. Higher areas of the brain can also send visual input back to neurons in lower areas of the visual cortex. [...] As humans, we have the ability to see with the mind's eye—to have a perceptual experience in the absence of visual input. For example, PET scans have shown that when subjects, seated in a room, imagine they are at their front door starting to walk either to the left or right, activation begins in the visual association cortex, the parietal cortex, and the prefrontal cortex—all higher cognitive processing centers of the brain.

A biological basis for mental imagery is found in the deeper portions of the brain below the neocortex. In a large study with 285 participants, Tabi, Maio, Attaallah, et al. (2022) investigated the association between an established measure of visual mental imagery, Vividness of Visual Imagery Questionnaire (VVIQ) scores, and volumes of brain structures including the hippocampus, amygdala, primary motor cortex, primary visual cortex and the fusiform gyrus. Tabi et al. (2022) found significant positive correlations between visual imagery vividness and the volumes of the hippocampus and primary visual cortex. 

 

VVIQ correlations with Hippocampal CA & GC-ML-DG volumes

Significant positive correlations were also obtained between VVIQ scores and hippocampal structures including Bilateral CA1, CA3, CA4 and Granule Cell (GC) and Molecular Layer (ML) of the Dentate Gyrus (DG). Follow-up analysis revealed that visual imagery was in particular correlated with the four subfields presented in the above illustration (Tabi et al., 2022).

The thalamus has been found to be discrete to other components in that it processes all forms of perceptional data relayed from both lower and higher components of the brain. Damage to this component can produce permanent perceptual damage, however when damage is inflicted upon the cerebral cortex, the brain adapts to neuroplasticity to amend any occlusions for perception. It can be thought that the neocortex is a sophisticated memory storage warehouse in which data received as an input from sensory systems are compartmentalized via the cerebral cortex. This would essentially allow for shapes to be identified, although given the lack of filtering input produced internally, one may as a consequence, hallucinate—essentially seeing something that isn't received as an input externally but rather internal (i.e. an error in the filtering of segmented sensory data from the cerebral cortex may result in one seeing, feeling, hearing or experiencing something that is inconsistent with reality).

Not all people have the same mental imagery ability. For many, when the eyes are closed, the perception of darkness prevails. However, some people are able to perceive colorful, dynamic imagery (McKellar, 1957). The use of hallucinogenic drugs increases the subject's ability to consciously access mental imagery including synaestesia (McKellar, 1957).

Furthermore, the pineal gland is a hypothetical candidate for producing a mind's eye. Rick Strassman and others have postulated that during near-death experiences (NDEs) and dreaming, the gland might secrete the hallucinogenic chemical N,N-Dimethyltryptamine (DMT) to produce internal visuals when external sensory data is occluded. However, this hypothesis has yet to be fully supported with neurochemical evidence and plausible mechanism for DMT production.

The condition where a person lacks mental imagery is called aphantasia. The term was first suggested in a 2015 study.

Common examples of mental images include daydreaming and the mental visualization that occurs while reading a book. Another is of the pictures summoned by athletes during training or before a competition, outlining each step they will take to accomplish their goal. When a musician hears a song, they can sometimes "see" the song notes in their head, as well as hear them with all their tonal qualities. This is considered different from an after-effect, such as an afterimage. Calling up an image in our minds can be a voluntary act, so it can be characterized as being under various degrees of conscious control.

There are several theories as to how mental images are formed in the mind. These include the dual-code theory, the propositional theory, and the functional-equivalency hypothesis. The dual-code theory, created by Allan Paivio in 1971, is the theory that we use two separate codes to represent information in our brains: image codes and verbal codes. Image codes are things like thinking of a picture of a dog when you are thinking of a dog, whereas a verbal code would be to think of the word "dog". Another example is the difference between thinking of abstract words such as justice or love and thinking of concrete words like elephant or chair. When abstract words are thought of, it is easier to think of them in terms of verbal codes—finding words that define them or describe them. With concrete words, it is often easier to use image codes and bring up a picture of a human or chair in your mind rather than words associated or descriptive of them.

The propositional theory involves storing images in the form of a generic propositional code that stores the meaning of the concept not the image itself. The propositional codes can either be descriptive of the image or symbolic. They are then transferred back into verbal and visual code to form the mental image.

The functional-equivalency hypothesis is that mental images are "internal representations" that work in the same way as the actual perception of physical objects. In other words, the picture of a dog brought to mind when the word dog is read is interpreted in the same way as if the person looking at an actual dog before them.

Research has occurred to designate a specific neural correlate of imagery; however, studies show a multitude of results. Most studies published before 2001 suggest neural correlates of visual imagery occur in Brodmann area 17. Auditory performance imagery have been observed in the premotor areas, precunes, and medial Brodmann area 40. Auditory imagery in general occurs across participants in the temporal voice area (TVA), which allows top-down imaging manipulations, processing, and storage of audition functions. Olfactory imagery research shows activation in the anterior piriform cortex and the posterior piriform cortex; experts in olfactory imagery have larger gray matter associated to olfactory areas. Tactile imagery is found to occur in the dorsolateral prefrontal area, inferior frontal gyrus, frontal gyrus, insula, precentral gyrus, and the medial frontal gyrus with basal ganglia activation in the ventral posteriomedial nucleus and putamen (hemisphere activation corresponds to the location of the imagined tactile stimulus). Research in gustatory imagery reveals activation in the anterior insular cortex, frontal operculum, and prefrontal cortex. Novices of a specific form of mental imagery show less gray matter than experts of mental imagery congruent to that form. A meta-analysis of neuroimagery studies revealed significant activation of the bilateral dorsal parietal, interior insula, and left inferior frontal regions of the brain. Causal evidence from neurological patients with brain lesions demonstrates that vivid visual mental imagery is possible even when occipital visual areas are lesioned or disconnected from more anterior cortex. Visual mental imagery can instead be impaired by left temporal damage. Consistent with these findings, a meta-analysis of 27 neuroimaging studies demonstrated imagery-related activity in a region of the left ventral temporal cortex, which was dubbed the Fusiform Imagery Node. An additional Bayesian analysis excluded a role for occipital cortex in visual mental imagery, consistent with the evidence from neurological patients.

Imagery has been thought to cooccur with perception; however, participants with damaged sense-modality receptors can sometimes perform imagery of said modality receptors. Neuroscience with imagery has been used to communicate with seemingly unconscious individuals through fMRI activation of different neural correlates of imagery, demanding further study into low quality consciousness. A study on one patient with one occipital lobe removed found the horizontal area of their visual mental image was reduced.

Neural substrates of visual imagery

Visual imagery is the ability to create mental representations of things, people, and places that are absent from an individual’s visual field. This ability is crucial to problem-solving tasks, memory, and spatial reasoning. Neuroscientists have found that imagery and perception share many of the same neural substrates, or areas of the brain that function similarly during both imagery and perception, such as the visual cortex and higher visual areas. Kosslyn and colleagues (1999) showed that the early visual cortex, Area 17 and Area 18/19, is activated during visual imagery. They found that inhibition of these areas through repetitive transcranial magnetic stimulation (rTMS) resulted in impaired visual perception and imagery. Furthermore, research conducted with lesioned patients has revealed that visual imagery and visual perception have the same representational organization. This has been concluded from patients in which impaired perception also experience visual imagery deficits at the same level of the mental representation.

Behrmann and colleagues (1992) describe a patient C.K., who provided evidence challenging the view that visual imagery and visual perception rely on the same representational system. C.K. was a 33-year old man with visual object agnosia acquired after a vehicular accident. This deficit prevented him from being able to recognize objects and copy objects fluidly. Surprisingly, his ability to draw accurate objects from memory indicated his visual imagery was intact and normal. Furthermore, C.K. successfully performed other tasks requiring visual imagery for judgment of size, shape, color, and composition. These findings conflict with previous research as they suggest there is a partial dissociation between visual imagery and visual perception. C.K. exhibited a perceptual deficit that was not associated with a corresponding deficit in visual imagery, indicating that these two processes have systems for mental representations that may not be mediated entirely by the same neural substrates.

Schlegel and colleagues (2013) conducted a functional MRI analysis of regions activated during manipulation of visual imagery. They identified 11 bilateral cortical and subcortical regions that exhibited increased activation when manipulating a visual image compared to when the visual image was just maintained. These regions included the occipital lobe and ventral stream areas, two parietal lobe regions, the posterior parietal cortex and the precuneus lobule, and three frontal lobe regions, the frontal eye fields, dorsolateral prefrontal cortex, and the prefrontal cortex. Due to their suspected involvement in working memory and attention, the authors propose that these parietal and prefrontal regions, and occipital regions, are part of a network involved in mediating the manipulation of visual imagery. These results suggest a top-down activation of visual areas in visual imagery.

Using Dynamic Causal Modeling (DCM) to determine the connectivity of cortical networks, Ishai et al. (2010) demonstrated that activation of the network mediating visual imagery is initiated by prefrontal cortex and posterior parietal cortex activity. Generation of objects from memory resulted in initial activation of the prefrontal and the posterior parietal areas, which then activate earlier visual areas through backward connectivity. Activation of the prefrontal cortex and posterior parietal cortex has also been found to be involved in retrieval of object representations from long-term memory, their maintenance in working memory, and attention during visual imagery. Thus, Ishai et al. suggest that the network mediating visual imagery is composed of attentional mechanisms arising from the posterior parietal cortex and the prefrontal cortex.

Vividness of visual imagery is a crucial component of an individual’s ability to perform cognitive tasks requiring imagery. Vividness of visual imagery varies not only between individuals but also within individuals. Dijkstra and colleagues (2017) found that the variation in vividness of visual imagery is dependent on the degree to which the neural substrates of visual imagery overlap with those of visual perception. They found that overlap between imagery and perception in the entire visual cortex, the parietal precuneus lobule, the right parietal cortex, and the medial frontal cortex predicted the vividness of a mental representation. The activated regions beyond the visual areas are believed to drive the imagery-specific processes rather than the visual processes shared with perception. It has been suggested that the precuneus contributes to vividness by selecting important details for imagery. The medial frontal cortex is suspected to be involved in the retrieval and integration of information from the parietal and visual areas during working memory and visual imagery. The right parietal cortex appears to be important in attention, visual inspection, and stabilization of mental representations. Thus, the neural substrates of visual imagery and perception overlap in areas beyond the visual cortex and the degree of this overlap in these areas correlates with the vividness of mental representations during imagery.

Philosophical ideas

Mental images are an important topic in classical and modern philosophy, as they are central to the study of knowledge. In the Republic, Book VII, Plato has Socrates present the Allegory of the Cave: a prisoner, bound and unable to move, sits with his back to a fire watching the shadows cast on the cave wall in front of him by people carrying objects behind his back. These people and the objects they carry are representations of real things in the world. Unenlightened man is like the prisoner, explains Socrates, a human being making mental images from the sense data that he experiences.

The eighteenth-century philosopher Bishop George Berkeley proposed similar ideas in his theory of idealism. Berkeley stated that reality is equivalent to mental images—our mental images are not a copy of another material reality but that reality itself. Berkeley, however, sharply distinguished between the images that he considered to constitute the external world, and the images of individual imagination. According to Berkeley, only the latter are considered "mental imagery" in the contemporary sense of the term.

The eighteenth century British writer Dr. Samuel Johnson criticized idealism. When asked what he thought about idealism, he is alleged to have replied "I refute it thus!" as he kicked a large rock and his leg rebounded. His point was that the idea that the rock is just another mental image and has no material existence of its own is a poor explanation of the painful sense data he had just experienced.

David Deutsch addresses Johnson's objection to idealism in The Fabric of Reality when he states that, if we judge the value of our mental images of the world by the quality and quantity of the sense data that they can explain, then the most valuable mental image—or theory—that we currently have is that the world has a real independent existence and that humans have successfully evolved by building up and adapting patterns of mental images to explain it. This is an important idea in scientific thought.

Critics of scientific realism ask how the inner perception of mental images actually occurs. This is sometimes called the "homunculus problem" (see also the mind's eye). The problem is similar to asking how the images you see on a computer screen exist in the memory of the computer. To scientific materialism, mental images and the perception of them must be brain-states. According to critics, scientific realists cannot explain where the images and their perceiver exist in the brain. To use the analogy of the computer screen, these critics argue that cognitive science and psychology have been unsuccessful in identifying either the component in the brain (i.e., "hardware") or the mental processes that store these images (i.e. "software").

In experimental psychology

Cognitive psychologists and (later) cognitive neuroscientists have empirically tested some of the philosophical questions related to whether and how the human brain uses mental imagery in cognition.

Mental rotation task (diagram).jpg

One theory of the mind that was examined in these experiments was the "brain as serial computer" philosophical metaphor of the 1970s. Psychologist Zenon Pylyshyn theorized that the human mind processes mental images by decomposing them into an underlying mathematical proposition. Roger Shepard and Jacqueline Metzler challenged that view by presenting subjects with 2D line drawings of groups of 3D block "objects" and asking them to determine whether that "object" is the same as a second figure, some of which rotations of the first "object". Shepard and Metzler proposed that if we decomposed and then mentally re-imaged the objects into basic mathematical propositions, as the then-dominant view of cognition "as a serial digital computer" assumed, then it would be expected that the time it took to determine whether the object is the same or not would be independent of how much the object had been rotated. Shepard and Metzler found the opposite: a linear relationship between the degree of rotation in the mental imagery task and the time it took participants to reach their answer.

This mental rotation finding implied that the human mind—and the human brain—maintains and manipulates mental images as topographic and topological wholes, an implication that was quickly put to test by psychologists. Stephen Kosslyn and colleagues showed in a series of neuroimaging experiments that the mental image of objects like the letter "F" are mapped, maintained and rotated as an image-like whole in areas of the human visual cortex. Moreover, Kosslyn's work showed that there are considerable similarities between the neural mappings for imagined stimuli and perceived stimuli. The authors of these studies concluded that, while the neural processes they studied rely on mathematical and computational underpinnings, the brain also seems optimized to handle the sort of mathematics that constantly computes a series of topologically-based images rather than calculating a mathematical model of an object.

Recent studies in neurology and neuropsychology on mental imagery have further questioned the "mind as serial computer" theory, arguing instead that human mental imagery manifests both visually and kinesthetically. For example, several studies have provided evidence that people are slower at rotating line drawings of objects such as hands in directions incompatible with the joints of the human body, and that patients with painful, injured arms are slower at mentally rotating line drawings of the hand from the side of the injured arm.

Some psychologists, including Kosslyn, have argued that such results occur because of interference in the brain between distinct systems in the brain that process the visual and motor mental imagery. Subsequent neuroimaging studies showed that the interference between the motor and visual imagery system could be induced by having participants physically handle actual 3D blocks glued together to form objects similar to those depicted in the line-drawings. Amorim et al. have shown that, when a cylindrical "head" was added to Shepard and Metzler's line drawings of 3D block figures, participants were quicker and more accurate at solving mental rotation problems. They argue that motoric embodiment is not just "interference" that inhibits visual mental imagery but is capable of facilitating mental imagery.

As cognitive neuroscience approaches to mental imagery continued, research expanded beyond questions of serial versus parallel or topographic processing to questions of the relationship between mental images and perceptual representations. Both brain imaging (fMRI and ERP) and studies of neuropsychological patients have been used to test the hypothesis that a mental image is the reactivation, from memory, of brain representations normally activated during the perception of an external stimulus. In other words, if perceiving an apple activates contour and location and shape and color representations in the brain’s visual system, then imagining an apple activates some or all of these same representations using information stored in memory. Early evidence for this idea came from neuropsychology. Patients with brain damage that impairs perception in specific ways, for example by damaging shape or color representations, seem to generally to have impaired mental imagery in similar ways. Studies of brain function in normal human brains support this same conclusion, showing activity in the brain’s visual areas while subjects imagined visual objects and scenes.

The previously mentioned and numerous related studies have led to a relative consensus within cognitive science, psychology, neuroscience, and philosophy on the neural status of mental images. In general, researchers agree that, while there is no homunculus inside the head viewing these mental images, our brains do form and maintain mental images as image-like wholes. The problem of exactly how these images are stored and manipulated within the human brain, in particular within language and communication, remains a fertile area of study.

One of the longest-running research topics on the mental image has basis on the fact that people report large individual differences in the vividness of their images. Special questionnaires have been developed to assess such differences, including the Vividness of Visual Imagery Questionnaire (VVIQ) developed by David Marks. Laboratory studies have suggested that the subjectively reported variations in imagery vividness are associated with different neural states within the brain and also different cognitive competences such as the ability to accurately recall information presented in pictures Rodway, Gillies and Schepman used a novel long-term change detection task to determine whether participants with low and high vividness scores on the VVIQ2 showed any performance differences. Rodway et al. found that high vividness participants were significantly more accurate at detecting salient changes to pictures compared to low-vividness participants. This replicated an earlier study.

Recent studies have found that individual differences in VVIQ scores can be used to predict changes in a person's brain while visualizing different activities. Functional magnetic resonance imaging (fMRI) was used to study the association between early visual cortex activity relative to the whole brain while participants visualized themselves or another person bench pressing or stair climbing. Reported image vividness correlates significantly with the relative fMRI signal in the visual cortex. Thus, individual differences in the vividness of visual imagery can be measured objectively.

Logie, Pernet, Buonocore and Della Sala (2011) used behavioural and fMRI data for mental rotation from individuals reporting vivid and poor imagery on the VVIQ. Groups differed in brain activation patterns suggesting that the groups performed the same tasks in different ways. These findings help to explain the lack of association previously reported between VVIQ scores and mental rotation performance.

Training and learning styles

Some educational theorists have drawn from the idea of mental imagery in their studies of learning styles. Proponents of these theories state that people often have learning processes that emphasize visual, auditory, and kinesthetic systems of experience. According to these theorists, teaching in multiple overlapping sensory systems benefits learning, and they encourage teachers to use content and media that integrates well with the visual, auditory, and kinesthetic systems whenever possible.

Educational researchers have examined whether the experience of mental imagery affects the degree of learning. For example, imagining playing a five-finger piano exercise (mental practice) resulted in a significant improvement in performance over no mental practice—though not as significant as that produced by physical practice. The authors of the study stated that "mental practice alone seems to be sufficient to promote the modulation of neural circuits involved in the early stages of motor skill learning".

Visualization and religion

Mental visualization is used across world religions, particularly as an aid for prayer or meditation.

Christianity

Opinions on the value of visualization vary within Christianity. In Catholicism, visualization plays a central role in the recitation of the Rosary, where it may be used to visualize Biblical scenes. In Eastern Orthodoxy, however, image-based prayer is generally frowned upon, because it is seen as an opening for demonic influence, and as contradictory to the aims of hesychastic prayer.

Tibetan traditions

In general, Vajrayana Buddhism and Bön utilize sophisticated visualization or imaginal (in the language of Jean Houston of Transpersonal Psychology) processes in the thoughtform construction of the yidam sadhana, kye-rim, and dzog-rim modes of meditation and in the yantra, thangka, and mandala traditions, where holding the fully realized form in the mind is a prerequisite prior to creating an 'authentic' new art work that will provide a sacred support or foundation for deity.

Substitution effects

Mental imagery can act as a substitute for the imagined experience: Imagining an experience can evoke similar cognitive, physiological, and/or behavioral consequences as having the corresponding experience in reality. At least four classes of such effects have been documented.

  1. Imagined experiences are attributed evidentiary value like physical evidence.
  2. Mental practice can instantiate the same performance benefits as physical practice and reduction central neuropathic pain.
  3. Imagined consumption of a food can reduce its actual consumption.
  4. Imagined goal achievement can reduce motivation for actual goal achievement.

Bayesian inference

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Bayesian_inference Bayesian inference ( / ...