Epigenetics of depression

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https://en.wikipedia.org/wiki/Epigenetics_of_depression 

Major depressive disorder is heavily influenced by environmental and genetic factors. These factors include epigenetic modification of the genome in which there is a persistent change in gene expression without a change in the actual DNA sequence. Genetic and environmental factors can influence the genome throughout a life; however, an individual is most susceptible during childhood. Early life stresses that could lead to major depressive disorder include periodic maternal separation, child abuse, divorce, and loss. These factors can result in epigenetic marks that can alter gene expression and impact the development of key brain regions such as the hippocampus. Epigenetic factors, such as methylation, could serve as predictors for the effectiveness of certain antidepressant treatments. Currently, antidepressants can be used to stabilize moods and decrease global DNA methylation levels, but they could also be used to determine the risk of depression caused by epigenetic changes. Identifying gene with altered expression could result in new antidepressant treatments.

Epigenetic alterations in depression

Histone deacetylases

Histone deacetylases (HDACs) are a class of enzymes that remove acetyl groups from histones. Different HDACs play different roles in response to depression, and these effects often vary in different parts of the body. In the nucleus accumbens (NaC), it is generally found that H3K14 acetylation decreases after chronic stress (used to produce a depression-like state in rodent model systems). However, after a while, this acetylation begins to increase again, and is correlated with a decrease in the activity and production of HDAC2. Adding HDAC2i (an HDAC2 inhibitor) leads to an improvement of the symptoms of depression in animal model systems. Furthermore, mice with a dominant negative HDAC2 mutation, which suppresses HDAC2 enzymatic activity, generally show less depressive behavior than mice who do not have this dominant negative mutation. HDAC5 shows the opposite trend in the NaC. A lack of HDAC5 leads to an increase in depressive behaviors. This is thought to be due to the fact that HDAC2 targets have antidepressant properties, while targets of HDAC5 have depressant properties.

In the hippocampus, there is a correlation between decreased acetylation and depressive behavior in response to stress. For example, H3K14 and H4K12 acetylation was found to be decreased, as well as general acetylation across histones H2B and H3. Another study found that HDAC3 was decreased in individuals resilient to depression. In the hippocampus, increased HDAC5 was found with increased depressive behavior (unlike in the nucleus accumbens).

Histone methyltransferases

Like HDACs, histone methyltransferases (HMTs) alter histones, but these enzymes are involved in the transfer of methyl groups to the histone's arginine and lysine residues. Chronic stress has been found to decrease the levels of a number of HMTs, such as G9a, in the NAc of susceptible mice. Conversely, in resilient mice, these HMTs have increased activity. H3K9 and H3K27 have less methylation when depressive behavior is seen. The hippocampus also experiences a number of histone methylation changes: H3K27-trimethylation is hypomethylated in response to stress, while H3K9-trimethylation and H3K4-trimethylation are hypermethylated in response to short term stress. However, H3K9-trimethylation and H3K4-trimethylation can also be hypomethylated in response to chronic, long term stress. In general, stress leading to depression is correlated with a decrease in methylation and a decrease in the activity of HMTs.

Brain-derived neurotrophic factor

Brain-derived neurotrophic factor (BDNF) is a neurotrophic growth factor that plays an important role in memory, learning, and higher thinking. It has been found that BDNF plasma levels and hippocampal volume are decreased in individuals suffering from depression. The expression of BDNF can be affected by different epigenetic modifications, and BDNF promoters can be individually regulated by different epigenetic alterations. MeCP2 can act as a repressor and has been shown to regulate BDNF when activated. Depolarization of neurons causing an increase in calcium leads to the phosphorylation of MeCP2, which results in a decrease in the binding of MeCP2 to BDNF promoter IV. Because MeCP2 can no longer bind to the BDNF promoter and repress transcription, BDNF levels increase and neuronal development improves. When there is direct methylation of the BDNF promoter, transcription of BDNF is repressed. Stressful situations have been shown to cause increased methylation of BDNF promoter IV, which causes an increase in MeCP2 binding, and as a result reduction in the activity of BDNF in the hippocampus and depressive behavior. BDNF maintains the survival of neurons in the hippocampus, and decreased levels can cause hippocampal atrophy. Also, there was found to be increased methylation of BDNF region IV CpGs in the Wernicke area of the brain in suicidal individuals. The interaction of BDNF and MeCP2 is complex, and there are instances where MeCP2 can cause an increase in BDNF levels instead of repressing. Previous studies have found that in MeCP2 knockout mice, the release and trafficking of BDNF within the neurons are significantly decreased in the hippocampus. Another epigenetic modification of BDNF promoters is the neuron-restrictive silencing factor (REST or NRSF) which epigenetically regulates the BDNF promoter I and is repressed by MeCP2. Like MeCP2, REST has also been found to inhibit BDNF transcription.

Hypothalamic-pituitary-adrenal axis

HPA axis diagram

In the hypothalamic-pituitary-adrenal axis (HPA Axis), corticotropin-releasing factor (CRF) is secreted by the hypothalamus in response to stress and other normal body processes. CRH then acts on the anterior pituitary and causes it to secrete adrenocorticotropic hormone (ACTH). ACTH acts on the adrenal cortex to secrete cortisol, which acts as a negative feedback indicator of the pathway. When an individual is exposed to stressful situations, the HPA axis activates the sympathetic nervous system and also increases the production of CRF, ACTH, and cortisol, which in turn increases blood glucose levels and suppresses the immune system. Increased expression of CRF has been found in the cerebrospinal fluid in depressed monkeys and rats, as well as individuals with depression. Increased CRF levels have also been seen in the hypothalamus of depressed individuals. It was found that pregnant mice in early gestation stage who were exposed to chronic stress produced offspring with a decreased methylation of the CRF promoter in the hypothalamus area. This decreased methylation would cause increased expression of CRF and thus, increased activity of the HPA axis. The higher levels of the HPA axis in response to chronic stress can also cause damage to the hippocampus region of the brain. Increased cortisol levels can lead to a decrease in hippocampal volume which is commonly seen in depressed individuals.

Glial cell line-derived neurotrophic factor

Glial cell-derived neurotrophic factor (GDNF) is a protein that aids in the survival and differentiation of dopaminergic neurons. By looking at expression levels in the nucleus accumbens, it is seen that GDNF expression is decreased in strains of mice susceptible to depression. It has also been shown that increased GDNF expression in the ventral tegmental area is present in mice that are not susceptible to social defeat stress by promoting the survival of neurons. The ventral tegmental area and nucleus accumbens network of the mesolimbic dopamine system is thought to be involved in the resistance and susceptibility to chronic stress (which leads to depressed behavior). Thus it is seen that GDNF, by protecting neurons of the mesolimbic pathway, helps to protect against depressive behavior. After chronic stress, there are a number of changes that result in the reduction of GDNF levels in the nucleus accumbens. This decrease is associated with decreased H3 acetylation and decreased H3K4-trimethylation, as well as an increased amount of DNA methylation at particular CpG sites on the GDNF promoter. This DNA methylation is associated with histone deacetylase 2 and methyl CpG binding protein 2 (MeCP2) recruitment to the GDNF promoter. Increased HDAC activity results in a reduction of GDNF expression, since HDAC causes the decreased acetylation at H3. Alternatively, knocking out HDACs (via HDAC interference) results in normalization of GDNF levels, and as a result, decreased depression like behavior, even in susceptible strains of mice. Cyclic-AMP response element-binding protein (CREB), which is thought to be involved in GDNF regulation, associates with the aforementioned MeCP2, and complexes to methylated CpG sites on the GDNF promoter. This recruitment of CREB plays a role in the repression of GDNF in the nucleus accumbens. As further evidence that DNA methylation plays a role in depressive behavior, delivery of DNA methyltransferase inhibitors results in a reversal of depression-like behaviors.

It is seen that DNA methylation of the GDNF promoter region results in the recruitment of MeCP2 and HDACs, resulting in an epigenetic alteration of the histone marks. This correlates to an increase in depression-like behavior.

Glucocorticoid receptor

Glucocorticoid receptors (GR) are receptors to which cortisol (and other glucocorticoids) bind. The bound receptor is involved in the regulation of gene transcription. The GR gene promoter region has a sequence that allows for binding by the transcription factor nerve growth factor induced protein A (NGFI-A), which is involved in neuronal plasticity. In rats, it has been shown that individuals less susceptible to depressive behavior have increased binding of NGFI-A to the promoter region of the GR gene, specifically in the hippocampus. As a result, there is an increased amount of hippocampal GR expression, both in transcription of its mRNA and overall protein level.

This is associated with an increase in acetylation of H3K9 in the GR promoter region. Methylation of CpG islands in the promoter region of GR leads to a decrease in the ability of NGFI-A to bind to the GR promoter region. It has also been experimentally shown that methylation of CpG sites in the enhancer region bound by NGFI-A is detrimental to the ability of NGFI-A to bind to the promoter region. Furthermore, the methylation of the promoter region results in a decrease in recruitment of the CREB-binding protein, which has histone acetyltransferase ability. This results in less acetylation of the histones, which has been shown to be a modification that takes place within individuals less susceptible to depression.

Due to environmental factors, there is a decrease in methylation of the promoter region of the GR gene, which then allows for increased binding of the NGFI-A protein, and as a result, an increase in the expression of the GR gene. This results in decreased depressive behavior.

Treatment

Antidepressants

Through computational methodology, epigenetics has been found to play a critical role in mood disorder susceptibility and development, and has also been shown to mediate treatment response to SSRI medications. SSRI medications including fluoxetine, paroxetine, and escitalopram reduce gene expression and enzymatic activity related to methylation and acetylation pathways in numerous brain regions implicated in patients with major depression.

Pharmacogenetic research has focused on epigenetic factors related to BDNF, which has been a biomarker for neuropsychiatric diseases. BDNF has been shown to be sensitive to the prolonged effects of stress (a common risk factor of depressive phenotypes), with epigenetic modifications (primarily histone methylation) at BDNF promoters and splice variants. Such variation in gene splicing and repressed hippocampal BDNF expression is associated with major depressive disorder while increased expression in this region is associated with successful antidepressant treatment. Patients suffering from major depression and bipolar disorder show increased methylation at BDNF promoters and reduced BDNF mRNA levels in the brain and in blood monocytes while SSRI treatment in patients with depression results in decreased histone methylation and increased BDNF levels.

In addition to the BDNF gene, micro RNAs (miRNAs) play a role in mood disorders, and transcript levels are suggested in SSRI treatment efficacy. Post-mortem work in patients with major depressive disorder, as well as other psychiatric diseases, show that miRNAs play a critical role in regulating brain structure via synaptic plasticity and neurogenesis. Increased hippocampal neural development plays a role in the efficacy of antidepressant treatment, while reductions in such development is related to neuropsychiatric disorders. In particular, the miRNA MIR-16 plays a critical role in regulating these processes in individuals with mood disorders. Increased hippocampal MIR-16 inhibits proteins which promote neurogenesis including the serotonin transporter (SERT), which is the target of SSRI therapeutics. MIR-16 downregulates SERT expression in humans, which decreases the number of serotonin transporters. Inhibition of MIR-16 therefore promotes SERT production and serves as a target for SSRI therapeutics. SSRI medications increase neurogenesis in the hippocampus by reductions in MIR-16, thereby restoring hippocampal neuronal activity following treatment in patients suffering from neuropsychiatric disorders. In patients with major depressive disorder, treatment with SSRI medications results in differential expression of 30 miRNAs, half of which play a role in modulating neuronal structure and/or are implicated in psychiatric disorders.

Understanding epigenetic profiles of patients suffering from neuropsychiatric disorders in key brain regions has led to more knowledge of patient outcome following SSRI treatment. Genome wide association studies seek to assess individual polymorphisms in genes which are implicated in depressive phenotypes, and aid in the efficacy of pharmacogenetic studies. Single-nucleotide polymorphisms of the 5-HT(2A) gene correlated with paroxetine discontinuation due to side effects in a group of elderly patients with major depression, but not mirtazapine (a non-SSRI antidepressant) discontinuation. In addition, hypomethylation of the SERT promoter was correlated with poor patient outcomes and treatment success following 6 weeks of escitalopram treatment. Such work addressing methylation patterns in the periphery has been shown to be comparable to methylation patterns in brain tissue, and provides information allowing for tailored pharmacogenetic approaches.

BDNF as a serotonin modulator

Decreased brain-derived neurotrophic factor (BDNF) is known to be associated with depression. Research suggests that increasing BDNF can reverse some symptoms of depression. For instance, increased BDNF signaling can reverse the reduced hippocampal brain signaling observed in animal models of depression. BDNF is involved in depression through its effects on serotonin. BDNF has been shown to promote the development, function, and expression of serotonergic neurons. Because more active serotonin results in more positive moods, antidepressants work to increase serotonin levels. Tricyclic antidepressants generally work by blocking serotonin transporters in order to keep serotonin in the synaptic cleft where it is still active. Noradrenergic and specific serotonergic antidepressants antagonize serotonin receptors. Noradrenergic and specific serotonergic antidepressants (NaSSAs) such as miratzapine and tricyclic antidepressants such as imapramine both increased BDNF in the cerebral cortices and hippocampi of rats. Because BDNF mRNA levels increase with long-term miratzapine use, increasing BDNF gene expression may be necessary for improvements in depressive behaviors. This also increases the potential for neuronal plasticity. Generally, these antidepressants increase peripheral BDNF levels by reducing methylation at BDNF promoters that are known to modulate serotonin. As BDNF expression is increased when H3K27me3 is decreased with antidepressant treatment, BDNF increases its effect on serotonin modulation. It modulates serotonin by downregulating the G protein-coupled receptor, 5-HT2A receptor protein levels in the hippocampus. This increased BDNF increases the inhibition of presynaptic serotonin uptake, which results in fewer symptoms of depression.

Effects of antidepressants on glucocorticoid receptors

Increased NGFI-A binding, and the resulting increase in glucocorticoid receptor (GR) expression, leads to a decrease in depression-like behavior. Antidepressants can work to increase GR levels in affected patients, suppressing depressive symptoms. Electric shock therapy, is often used to treat patients suffering from depression. It is found that this form of treatment results in an increase in NGFI-A expression levels. Electric shock therapy depolarizes a number of neurons throughout the brain, resulting in the increased activity of a number of intracellular pathways. This includes the cAMP pathway which, through downstream effects, results in expression of NGFI-A. Antidepressant drugs, such as Tranylcypromine and Imipramine were found to have a similar effect; treatment with these drugs led to increases in NGFI-A expression and subsequent GR expression. These two drugs are thought to alter synaptic levels of 5-HT, which then alters the activity level of the cAMP pathway. It is also known that increased glucocorticoid receptor expression has been shown to modulate the HPA pathway by increasing negative feedback. This increase in expression results from decreased methylation, increased acetylation and binding of HGFI-A transcription factor. This promotes a more moderate HPA response than seen in those with depression which then decreases levels of hormones associated with stress. Another antidepressant, Desipramine was found to increase GR density and GR mRNA expression in the hippocampus. It is thought that this is happening due to an interaction between the response element of GR and the acetyltransferase, CREB Binding Protein. Therefore, this antidepressant, by increasing acetylation, works to lessen the HPA response, and as a result, decrease depressive symptoms.

HDAC inhibitors as antidepressants

HDAC inhibitors have been show to cause antidepressant-like effects in animals. Research shows that antidepressants make epigenetic changes to gene transcription thus altering signaling. These gene expression changes are seen in the BDNF, CRF, GDNF, and GR genes (see above sections). Histone modifications are consistently reported to alter chromatin structure during depression by the removal of acetyl groups, and to reverse this, HDAC inhibitors work by countering the removal of acetyl groups on histones. HDAC inhibitors can decrease gene transcription in the hippocampus and prefrontal cortex that is increased as a characteristic of depression. In animal studies of depression, short-term administration of HDAC inhibitors reduced the fear response in mice, and chronic administration produced antidepressant-like effects. This suggests that long-term treatment of HDAC inhibitors help in the treatment of depression. Some studies show that administration of HDAC inhibitors like Vorinostat and Romidepsin, hematologic cancer drugs, can augment the effect of other antidepressants. These HDAC inhibitors may become antidepressants in the future, but clinical trials must further assess their efficacy in humans.

Emotional choice theory

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Emotional_choice_theory 

Emotional choice theory (also referred to as the "logic of affect") is a social scientific action model to explain human decision-making. Its foundation was laid in Robin Markwica’s monograph Emotional Choices published by Oxford University Press in 2018. It is considered an alternative model to rational choice theory and constructivist perspectives.

Overview

Markwica suggests that political and social scientists have generally employed two main action models to explain human decision-making: On the one hand, rational choice theory (also referred to as the "logic of consequences") views people as homo economicus and assumes that they make decisions to maximize benefit and to minimize cost. On the other hand, a constructivist perspective (also known as the "logic of appropriateness") regards people as homo sociologicus, who behave according to their social norms and identities. According to Markwica, recent research in neuroscience and psychology, however, shows that decision-making can be strongly influenced by emotion. Drawing on these insights, he develops "emotional choice theory," which conceptualizes decision-makers as homo emotionalis – "emotional, social, and physiological beings whose emotions connect them to, and separate them from, significant others."

Emotional choice theory posits that individual-level decision-making is shaped in significant ways by the interplay between people’s norms, emotions, and identities. While norms and identities are important long-term factors in the decision process, emotions function as short-term, essential motivators for change. These motivators kick in when persons detect events in the environment that they deem relevant to a need, goal, value, or concern.

The role of emotions in decision-making

Markwica contends that rational choice theory and constructivist approaches generally ignore the role of affect and emotion in decision-making. They typically treat choice selection as a conscious and reflective process based on thoughts and beliefs. Two decades of research in neuroscience, however, suggest that only a small fraction of the brain’s activities operate at the level of conscious reflection. The vast majority of its activities consist of unconscious appraisals and emotion. Markwica concludes that emotions play a significant role in shaping decision-making processes: "They inform us what we like and what we loathe, what is good and bad for us, and whether we do right or wrong. They give meaning to our relationships with others, and they generate physiological impulses to act."

The theory

Emotional choice theory is a unitary action model to organize, explain, and predict the ways in which emotions shape decision-making. One of its main assumptions is that the role of emotion in choice selection can be captured systematically by homo emotionalis. Markwica emphasizes that the theory is not designed to replace rational choice theory and constructivist approaches, or to negate their value. Rather, it is supposed to offer a useful complement to these perspectives. Its purpose is to enable scholars to explain a broader spectrum of decision-making.

The theory is developed in four main steps: The first part defines "emotion" and specifies the model’s main assumptions. The second part outlines how culture shapes emotions, while the third part delineates how emotions influence decision-making. The fourth part formulates the theory’s main propositions.

Defining "emotion" and the theory’s main assumptions

Emotional choice theory subscribes to a definition of "emotion" as a "transient, partly biologically based, partly culturally conditioned response to a stimulus, which gives rise to a coordinated process including appraisals, feelings, bodily reactions, and expressive behavior, all of which prepare individuals to deal with the stimulus."

Markwica notes that the term "emotional choice theory" and the way it contrasts with rational choice theory may create the impression that it casts emotion in opposition to rationality. However, he stresses that the model does not conceive of feeling and thinking as antithetical processes. Rather, it seeks to challenge rational choice theory’s monopoly over the notion of rationality. He argues that the rational choice understanding of rationality is problematic not for what it includes, but for what it omits. It allegedly leaves out important affective capacities that put humans in a position to make reasoned decisions. He points out that two decades of research in neuroscience and psychology has shattered the orthodox view that emotions stand in opposition to rationality. This line of work suggests that the capacity to feel is a prerequisite for reasoned judgment and rational behavior.

The influence of culture on emotions

Emotional choice theory is based on the assumption that while emotion is felt by individuals, it cannot be isolated from the social context in which it arises. It is inextricably intertwined with people’s cultural ideas and practices. This is why it is necessary to understand how emotion is molded by the cultural environment in which it is embedded. The theory draws on insights from sociology to delineate how actors’ norms about the appropriate experience and expression of affect shape their emotions. It does not specify the precise substantive content of norms in advance. Given that they vary from case to case, Markwica suggests that they need to be investigated inductively. The model describes the generic processes through which norms guide emotions: Norms affect emotions through what sociologist Arlie Russell Hochschild has termed "feeling rules," which inform people how to experience emotions in a given situation, and "display rules," which tell them how to express emotions.

The influence of emotions on decision-making

Emotional choice theory assumes that emotions are not only social but also corporeal experiences that are tied to an organism’s autonomic nervous system. People feel emotions physically, often before they are aware of them. It is suggested that these physiological processes can exert a profound influence on human cognition and behavior. They generate or stifle energy, which makes decision-making a continuously dynamic phenomenon. To capture this physiological dimension of emotions, the theory draws on research in psychology in general and appraisal theory in particular. Appraisal theorists have found that each discrete emotion, such as fear, anger, or sadness, has a logic of its own. It is associated with what social psychologist Jennifer Lerner has termed "appraisal tendencies" and what emotion researcher Nico Frijda has called "action tendencies." An emotion’s appraisal tendencies influence what and how people think, while its action tendencies shape what they want and do.

Emotional choice theory’s propositions

The core of emotional choice theory consists of a series of propositions about how emotions tend to influence decision-makers’ thinking and behavior through their appraisal tendencies and action tendencies: Fear often prompts an attentional bias toward potential threats and may cause actors to fight, flee, or freeze. Anger is associated with a sense of power and a bias in favor of high-risk options. Hope may boost creativity and persistence, but it can also further confirmation bias. Pride can both cause people to be more persistent and to disregard their own weaknesses. And humiliation can lead people to withdraw or, alternatively, to resist the humiliator.

Markwica emphasizes that even when emotions produce powerful impulses, individuals will not necessarily act on them. Emotional choice theory restricts itself to explaining and predicting the influence of emotions on decision-making in a probabilistic fashion. It also recognizes that emotions may mix, meld, or co-occur.

Reception

Emotional choice theory has been met with some praise but also with strong criticisms by political and social scientists and political psychologists.

For example, political scientist Dustin Tingley (Harvard University) considers the model "an intellectual tour de force" that "should be required reading for anyone in the social sciences who is doing applied research that features a role for emotions." In his opinion, even scholars from the rational choice school of thought would "benefit from the clear explication of how to think about emotion in strategic contexts." International relations scholar Neta Crawford (Boston University) recognizes that emotional choice theory seeks to "dramatically revise, if not overturn," our understanding of decision-making. She concludes that the model is "strong [...] on theoretical, methodological, and empirical grounds." However, she criticizes its disregard for important factors that would need to be taken into consideration to fully explain decision-making. For instance, the theory’s focus on the psychology and emotions of individual actors makes it difficult to account for group dynamics in decision-making processes such as groupthink, in her opinion. She also finds that the theory neglects the role of ideology and gender, including norms about femininity and masculinity. Similarly, Matthew Costlow (National Institute of Public Policy) criticizes that the model does not adequately take into account how mental illnesses and personality disorders may influence certain emotions and people’s ability to regulate them. He notes that U.S. President Abraham Lincoln and British Prime Minister Winston Churchill suffered from depression, for example, which presumably affected their emotions and, hence, their decision-making.

Political psychologist Rose McDermott (Brown University) considers emotional choice theory "remarkable for its creative integration of many facets of emotion into a single, detailed, comprehensive framework." She deems it an "important contribution" to the literature on decision-making, which can "easily serve as a foundational template for other scholars wishing to expand exploration into other emotions or other areas of application." Yet, she also notes "how deeply idiosyncratic the experience and expression of emotion is between individuals." In her eyes, this "does not make it impossible or pointless" to apply emotional choice theory, "but it does make it more difficult, and requires more and richer information sources than other models might demand." International relations scholar Adam Lerner (University of Cambridge) wonders whether emotions and their interpretations are not too context specific – both socially and historically – for their impacts to be understood systematically across time and space with emotional choice theory. He takes issue with the model’s complexity and concludes that it offers "relatively limited yield" when compared with rigorous historical analysis.

Political scientist Ignas Kalpokas (Vytautas Magnus University) regards emotional choice theory as "a long-overdue and successful attempt to conceptualize the logic of affect." He highlights the theory’s "real subversive and disruptive potential" and considers it "of particular necessity in today’s environment when traditional political models based on rationality and deliberation are crumbling in the face of populism, resurgent emotion-based identities, and post-truth." In his eyes, the model’s most significant "drawback" is the methodological difficulty of accessing another person’s emotions. When analysts are not able to obtain this information, they cannot employ the theory.

According to international relations scholar Keren Yarhi-Milo (Columbia University), the theory "proves a useful, additional approach to understanding the decision-making process of leaders." In her view, the model and its methodology "are novel and significantly advance not only our understanding of [emotions'] role in decision-making but also how to study them systematically." She highlights the theory’s assumption that "emotions themselves are shaped by the cultural milieu in which they are embedded." Contextualizing emotions in such a way is "important," she contends, because cultures, norms, and identities are bound to vary over time and space, which will, in turn, affect how people experience and express emotions. At the same time, Yarhi-Milo points out that the theory sacrifices parsimony by incorporating a number of psychological and cultural processes, such as the role of identity validation dynamics, compliance with norms about emotions, and the influence of individual psychological dispositions. She notes that the model’s focus on the inductive reconstruction of the cultural context of emotions puts a "significant burden" on analysts who apply it, because they need access to evidence that is typically not easy to come by.

Rational choice theory

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https://en.wikipedia.org/wiki/Rational_choice_theory 

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Economics
History Outline Index

Rational choice theory refers to a set of guidelines that help understand economic and social behaviour. The theory originated in the eighteenth century and can be traced back to political economist and philosopher, Adam Smith. The theory postulates that an individual will perform a cost-benefit analysis to determine whether an option is right for them. It also suggests that an individual's self-driven rational actions will help better the overall economy. Rational choice theory looks at three concepts: rational actors, self interest and the invisible hand.

Rationality can be used as an assumption for the behaviour of individuals in a wide range of contexts outside of economics. It is also used in political science, sociology, and philosophy.

Overview

The basic premise of rational choice theory is that the decisions made by individual actors will collectively produce aggregate social behaviour. The theory also assumes that individuals have preferences out of available choice alternatives. These preferences are assumed to be complete and transitive. Completeness refers to the individual being able to say which of the options they prefer (i.e. individual prefers A over B, B over A or are indifferent to both). Alternatively, transitivity is where the individual weakly prefers option A over B and weakly prefers option B over C, leading to the conclusion that the individual weakly prefers A over C. The rational agent will then perform their own cost-benefit analysis using a variety of criterion to perform their self-determined best choice of action.

One version of rationality is instrumental rationality, which involves achieving a goal using the most cost effective method without reflecting on the worthiness of that goal. Duncan Snidal emphasises that the goals are not restricted to self-regarding, selfish, or material interests. They also include other-regarding, altruistic, as well as normative or ideational goals.

Rational choice theory does not claim to describe the choice process, but rather it helps predict the outcome and pattern of choice. It is consequently assumed that the individual is self-interested or being homo economicus. Here, the individual comes to a decision that maximizes personal advantage by balancing costs and benefits. Proponents of such models, particularly those associated with the Chicago school of economics, do not claim that a model's assumptions are an accurate description of reality, only that they help formulate clear and falsifiable hypotheses. In this view, the only way to judge the success of a hypothesis is empirical tests. To use an example from Milton Friedman, if a theory that says that the behavior of the leaves of a tree is explained by their rationality passes the empirical test, it is seen as successful.

Without explicitly dictating the goal or preferences of the individual, it may be impossible to empirically test or invalidate the rationality assumption. However, the predictions made by a specific version of the theory are testable. In recent years, the most prevalent version of rational choice theory, expected utility theory, has been challenged by the experimental results of behavioral economics. Economists are learning from other fields, such as psychology, and are enriching their theories of choice in order to get a more accurate view of human decision-making. For example, the behavioral economist and experimental psychologist Daniel Kahneman won the Nobel Memorial Prize in Economic Sciences in 2002 for his work in this field.

William Stanley Jevons

Rational choice theory has proposed that there are two outcomes of two choices regarding human action. Firstly, the feasible region will be chosen within all the possible and related action. Second, after the preferred option has been chosen, the feasible region that has been selected was picked based on restriction of financial, legal, social, physical or emotional restrictions that the agent is facing. After that, a choice will be made based on the preference order.

The concept of rationality used in rational choice theory is different from the colloquial and most philosophical use of the word. In this sense, "rational" behaviour can refer to "sensible", "predictable", or "in a thoughtful, clear-headed manner." Rational choice theory uses a much more narrow definition of rationality. At its most basic level, behavior is rational if it is goal-oriented, reflective (evaluative), and consistent (across time and different choice situations). This contrasts with behavior that is random, impulsive, conditioned, or adopted by (unevaluative) imitation.

Early neoclassical economists writing about rational choice, including William Stanley Jevons, assumed that agents make consumption choices so as to maximize their happiness, or utility. Contemporary theory bases rational choice on a set of choice axioms that need to be satisfied, and typically does not specify where the goal (preferences, desires) comes from. It mandates just a consistent ranking of the alternatives. Individuals choose the best action according to their personal preferences and the constraints facing them. E.g., there is nothing irrational in preferring fish to meat the first time, but there is something irrational in preferring fish to meat in one instant and preferring meat to fish in another, without anything else having changed.

Actions, assumptions, and individual preferences

The basic premise of rational choice theory is that the decisions made by individual actors will collectively produce aggregate social behaviour. Thus, each individual makes a decision based on their own preferences and the constraints (or choice set) they face.

Rational choice theory can be viewed in different contexts. At an individual level, the theory suggests that the agent will decide on the action (or outcome) they most prefer. If the actions (or outcomes) are evaluated in terms of costs and benefits, the choice with the maximum net benefit will be chosen by the rational individual. Rational behaviour is not solely driven by monetary gain, but can also be driven by emotional motives.

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Utilitarianism

The theory can be applied to general settings outside of those identified by costs and benefits. In general, rational decision making entails choosing among all available alternatives the alternative that the individual most prefers. The "alternatives" can be a set of actions ("what to do?") or a set of objects ("what to choose/buy"). In the case of actions, what the individual really cares about are the outcomes that results from each possible action. Actions, in this case, are only an instrument for obtaining a particular outcome.

Formal statement

The available alternatives are often expressed as a set of objects, for example a set of j exhaustive and exclusive actions:

${\displaystyle A=\{a_{1},\ldots ,a_{i},\ldots ,a_{j}\}}$

For example, if a person can choose to vote for either Roger or Sara or to abstain, their set of possible alternatives is:

${\displaystyle A=\{{\text{Vote for Roger, Vote for Sara, Abstain}}\}}$

The theory makes two technical assumptions about individuals' preferences over alternatives:

• Completeness – for any two alternatives a_i and a_j in the set, either a_i is preferred to a_j, or a_j is preferred to a_i, or the individual is indifferent between a_i and a_j. In other words, all pairs of alternatives can be compared with each other.
• Transitivity – if alternative a₁ is preferred to a₂, and alternative a₂ is preferred to a₃, then a₁ is preferred to a₃.

Together these two assumptions imply that given a set of exhaustive and exclusive actions to choose from, an individual can rank the elements of this set in terms of his preferences in an internally consistent way (the ranking constitutes a partial ordering), and the set has at least one maximal element.

The preference between two alternatives can be:

• Strict preference occurs when an individual prefers a₁ to a₂ and does not view them as equally preferred.
• Weak preference implies that individual either strictly prefers a₁ over a₂ or is indifferent between them.
• Indifference occurs when an individual neither prefers a₁ to a₂, nor a₂ to a₁. Since (by completeness) the individual does not refuse a comparison, they must therefore be indifferent in this case.

Research that took off in the 1980s sought to develop models that drop these assumptions and argue that such behaviour could still be rational, Anand (1993). This work, often conducted by economic theorists and analytical philosophers, suggests ultimately that the assumptions or axioms above are not completely general and might at best be regarded as approximations.

Additional assumptions

• Perfect information: The simple rational choice model above assumes that the individual has full or perfect information about the alternatives, i.e., the ranking between two alternatives involves no uncertainty.
• Choice under uncertainty: In a richer model that involves uncertainty about the how choices (actions) lead to eventual outcomes, the individual effectively chooses between lotteries, where each lottery induces a different probability distribution over outcomes. The additional assumption of independence of irrelevant alternatives then leads to expected utility theory.
• Inter-temporal choice: when decisions affect choices (such as consumption) at different points in time, the standard method for evaluating alternatives across time involves discounting future payoffs.
• Limited cognitive ability: identifying and weighing each alternative against every other may take time, effort, and mental capacity. Recognising the cost that these impose or cognitive limitations of individuals gives rise to theories of bounded rationality.

Alternative theories of human action include such components as Amos Tversky and Daniel Kahneman's prospect theory, which reflects the empirical finding that, contrary to standard preferences assumed under neoclassical economics, individuals attach extra value to items that they already own compared to similar items owned by others. Under standard preferences, the amount that an individual is willing to pay for an item (such as a drinking mug) is assumed to equal the amount they are willing to be paid in order to part with it. In experiments, the latter price is sometimes significantly higher than the former (but see Plott and Zeiler 2005, Plott and Zeiler 2007 and Klass and Zeiler, 2013). Tversky and Kahneman do not characterize loss aversion as irrational. Behavioral economics includes a large number of other amendments to its picture of human behavior that go against neoclassical assumptions.

Utility maximization

Often preferences are described by their utility function or payoff function. This is an ordinal number that an individual assigns over the available actions, such as:

${\displaystyle u\left(a_{i}\right)>u\left(a_{j}\right).}$

The individual's preferences are then expressed as the relation between these ordinal assignments. For example, if an individual prefers the candidate Sara over Roger over abstaining, their preferences would have the relation:

${\displaystyle u\left({\text{Sara}}\right)>u\left({\text{Roger}}\right)>u\left({\text{abstain}}\right).}$

A preference relation that as above satisfies completeness, transitivity, and, in addition, continuity, can be equivalently represented by a utility function.

Benefits

The rational choice approach allows preferences to be represented as real-valued utility functions. Economic decision making then becomes a problem of maximizing this utility function, subject to constraints (e.g. a budget). This has many advantages. It provides a compact theory that makes empirical predictions with a relatively sparse model - just a description of the agent's objectives and constraints. Furthermore, optimization theory is a well-developed field of mathematics. These two factors make rational choice models tractable compared to other approaches to choice. Most importantly, this approach is strikingly general. It has been used to analyze not only personal and household choices about traditional economic matters like consumption and savings, but also choices about education, marriage, child-bearing, migration, crime and so on, as well as business decisions about output, investment, hiring, entry, exit, etc. with varying degrees of success.

In the field of political science rational choice theory has been used to help predict human decision making and model for the future; therefore it is useful in creating effective public policy, and enables the government to develop solutions quickly and efficiently.

Despite the empirical shortcomings of rational choice theory, the flexibility and tractability of rational choice models (and the lack of equally powerful alternatives) lead to them still being widely used.

Applications

Rational choice theory has become increasingly employed in social sciences other than economics, such as sociology, evolutionary theory and political science in recent decades. It has had far-reaching impacts on the study of political science, especially in fields like the study of interest groups, elections, behaviour in legislatures, coalitions, and bureaucracy. In these fields, the use of the rational choice theory to explain broad social phenomena is the subject of controversy.

Rational choice theory in politics

The relationship between the rational choice theory and politics takes many forms, whether that be in voter behaviour, the actions of world leaders or even the way that important matters are dealt with.

Voter behaviour shifts significantly thanks to rational theory, which is ingrained in human nature, the most significant of which occurs when there are times of economic trouble. This was assessed in detail by Anthony Downs who concluded that voters were acting on thoughts of higher income as a person ‘votes for whatever party he believes would provide him with the highest utility income from government action’. This is a significant simplification of how the theory influences people's thoughts but makes up a core part of rational theory as a whole. In a more complex fashion, voters will react often radically in times of real economic strife, which can lead to an increase in extremism. The government will be made responsible by the voters and thus they see a need to make a change. Some of the most infamous extremist parties came to power on the back of economic recessions, the most significant being the far right Nazi Party in Germany, who used the hyperinflation at the time to gain power rapidly, as they promised a solution and a scapegoat for the blame. There is a trend to this, as a comprehensive study carried out by three political scientists concluded, as a ‘turn to the right’ occurs and it is clear that it is the work of the rational theory because within ten years the politics returns to a more common state.

Anthony Downs also suggested that voting involves a cost/benefit analysis in order to determine how a person would vote. He argues that someone will vote if B+D>C, where B= The benefit of the voter winning, D= Satisfaction and C being the cost of voting. It is from this that we can determine that parties have moved their policy outlook to be more centric in order to maximise the amount of voters they have for support. This is becoming more and more prevalent with every election as each party tries to appeal to a broader range of voters. This is especially prevalent as there has been a decline in party memberships, meaning that each party has much less guaranteed votes. In the last 10 years there has been a 37% decrease in party memberships, with this trend having started soon after the Second World War. This shows that the electorate a leaning towards making informed, rational decisions as opposed to relying on a pattern of behaviours. Overall the electorate are becoming more inclined to vote based on recency factors in order to protect their interests and maximise their utility.

Meaning Rational Choice Theory has the ability to be used in modelling and forecasting, owing to its nature being derived from economic thought to explain human behaviour. This is useful in politics as the theory can quantify human decision making and behaviour into data that can be interpreted, helping to predict behaviours and outcomes. Therefore enabling the ability to direct and shape political thinking and campaigns, maximizing utility. 

As useful as the use of empirical data is in building a clear picture of voting behaviour it doesn't full show all aspects of political decision making whether that be from the electorate or the policy makers. As  brings the idea of commitment as a key concept to the behaviour of political agents. That it is not only self interest that is the outcome of personal cost benefit analysis but it is also the idea of shared interests. That the key idea of utility needs to be defined not only as material utility but also as experienced utility, these expansions to classical rational choice theory could then begin to remove the weakness in regards to morals of the agents which it aims to interoperate their actions.

A downfall of rational choice theory in a political sense, is that is the pursuit of individual goals can lead to collectively irrational outcomes. This problem of collective action can disincentivise people to vote. Even though a group of people may have common interests, they also have conflicting ones that cause misalignment within the group and therefore an outcome that does not benefit the group as a whole as people want to pursue their own individual interests. This problem is rooted in Rational Choice theory because of the theories emphasis on the rational agents performing their own cost-benefit analysis to maximize their self-interests. 

An example of this can be shown by some of the world’s most troubling problems, such as the climate crisis. Nation states can be seen as rational as they fulfil their own interests of economic growth, however, this economic growth often leads to pollution as increasing a nation’s factors of production takes a toll on the environment. It is irrational for a state to forego this economic growth as the cost of pollution does not entirely fall on them, as one state’s carbon emissions would not entirely affect that state alone, as it impacts elsewhere. This means the benefit of the economic growth outweighs the cost of pollution, according to the theory of Rational Choice. However, If all countries made this rational calculation it would lead to a massive amount of pollution. Making the outcome of a rational choice, a collectively irrational outcome.

Rational choice theory in international relations

Rational choice theory has become one of the major approaches in the study of international relations. Its proponents typically assume that states are the key actors in world politics and that they seek goals such as power, security, or wealth. They have applied rational choice theory to policy issues ranging from international trade and international cooperation to sanctions, arms competition, (nuclear) deterrence, and war.

For example, some scholars have examined how states can make credible threats to deter other states from a (nuclear) attack. Others have explored under what conditions states wage war against each other. Yet others have investigated under what circumstances the threat and imposition of international economic sanctions tend to succeed and when they are likely to fail.

Rational Choice theory in Social Interactions

Rational Choice Theory and Social exchange theory involves looking at all social relations in the form of costs and rewards, both tangible and non tangible.

According to Abell, Rational Choice Theory is "understanding individual actors... as acting, or more likely interacting, in a manner such that they can be deemed to be doing the best they can for themselves, given their objectives, resources, circumstances, as they seem them". Rational Choice Theory has been used to comprehend the complex social phenomena, of which derives from the actions and motivations of an individual. Individuals are often highly motivated by the wants and needs.

By making calculative decisions, it is considered as rational action. Individuals are often making calculative decisions in social situations by weighing out the pros and cons of an action taken towards a person. The decision to act on a rational decision is also dependent on the unforeseen benefits of the friendship. Homan mentions that actions of humans are motivated by punishment or rewards. This reinforcement through punishments or rewards determines the course of action taken by a person in a social situation as well. Individuals are motivated by mutual reinforcement and are also fundamentally motivated by the approval of others. Attaining the approval of others has been a generalized character, along with money, as a means of exchange in both Social and Economic exchanges. In Economic exchanges, it involves the exchange of goods or services. In Social exchange, it is the exchange of approval and certain other valued behaviors.

Rational Choice Theory in this instance, heavily emphasizes the individual's interest as a starting point for making social decisions. Despite differing view points about Rational choice theory, it all comes down to the individual as a basic unit of theory. Even though sharing, cooperation and cultural norms emerge, it all stems from an individual's initial concern about the self.

Social Exchange and Rational Choice Theory both comes down to an individual's efforts to meet their own personal needs and interests through the choices they make. Even though some may be done sincerely for the welfare of others at that point of time, both theories point to the benefits received in return. These returns may be received immediately or in the future, be it tangible or not.

Coleman discussed a number of theories to elaborate on the premises and promises of rational choice theory. One of the concepts that He introduced was Trust. It is where "individuals place trust, in both judgement and performance of others, based on rational considerations of what is best, given the alternatives they confront". In a social situation, there has to be a level of trust among the individuals. He noted that this level of trust is a consideration that an individual takes into concern before deciding on a rational action towards another individual. It affects the social situation as one navigates the risks and benefits of an action. By assessing the possible outcomes or alternatives to an action for another individual, the person is making a calculated decision. In another situation such as making a bet, you are calculating the possible lost and how much can be won. If the chances of winning exceeds the cost of losing, the rational decision would be to place the bet. Therefore, the decision to place trust in another individual involves the same rational calculations that are involved in the decision of making a bet.

Even though rational theory is used in Economics and Social settings, there are some similarities and differences. The concept of reward and reinforcement is parallel to each other while the concept of cost is also parallel to the concept of punishment. However, there is a difference of underlying assumptions in both contexts. In social a social setting, the focus is often on the current or past reinforcements instead of the future although there is no guarantee of immediate tangible or intangible returns from another individual. In Economics, decisions are made with heavier emphasis on future rewards.

Despite having both perspectives differ in focus, they primarily reflect on how individuals make different rational decisions when given an immediate or long-term circumstances to consider in their rational decision making.

Criticism

This theory critically helps us to understand the choices an individual or society makes. Even though some decisions are not entirely rational, it is possible that Rational Choice Theory still helps us to understand the motivations behind it. Moreover, there has been a lot of discourse about Rational Choice Theory. It has often been too individualistic, minimalistic and heavily focused on rational decisions in social actions. Sociologists tend to justify any human action as rational as individuals are solely motivated by the pursuit of self-interest. It does not consider the possibility of pure altruism of a social exchange between individuals.

Criticism

Daniel Kahneman

Both the assumptions and the behavioral predictions of rational choice theory have sparked criticism from various camps.

The limits of rationality

As mentioned above, some economists have developed models of bounded rationality, such as Herbert Simon, which hope to be more psychologically plausible without completely abandoning the idea that reason underlies decision-making processes. Simon argues factors such as imperfect information, uncertainty and time constraints all affect and limit our rationality, and therefore our decision making skills. Furthermore his concepts of 'satisficing' and 'optimizing' suggest sometimes because of these factors, we settle for a decision which is good enough, rather than the best decision. Other economists have developed more theories of human decision-making that allow for the roles of uncertainty, institutions, and determination of individual tastes by their socioeconomic environment (cf. Fernandez-Huerga, 2008).

Philosophical critiques

Martin Hollis and Edward J. Nell's 1975 book offers both a philosophical critique of neo-classical economics and an innovation in the field of economic methodology. Further, they outlined an alternative vision to neo-classicism based on a rationalist theory of knowledge. Within neo-classicism, the authors addressed consumer behaviour (in the form of indifference curves and simple versions of revealed preference theory) and marginalist producer behaviour in both product and factor markets. Both are based on rational optimizing behaviour. They consider imperfect as well as perfect markets since neo-classical thinking embraces many market varieties and disposes of a whole system for their classification. However, the authors believe that the issues arising from basic maximizing models have extensive implications for econometric methodology (Hollis and Nell, 1975, p. 2). In particular it is this class of models – rational behavior as maximizing behaviour – which provide support for specification and identification. And this, they argue, is where the flaw is to be found. Hollis and Nell (1975) argued that positivism (broadly conceived) has provided neo-classicism with important support, which they then show to be unfounded. They base their critique of neo-classicism not only on their critique of positivism but also on the alternative they propose, rationalism. Indeed, they argue that rationality is central to neo-classical economics – as rational choice – and that this conception of rationality is misused. Demands are made of it that it cannot fulfill. Ultimately, individuals do not always act rationally or conduct themselves in a utility maximising manner.

Duncan K. Foley (2003, p. 1) has also provided an important criticism of the concept of rationality and its role in economics. He argued that

“Rationality” has played a central role in shaping and establishing the hegemony of contemporary mainstream economics. As the specific claims of robust neoclassicism fade into the history of economic thought, an orientation toward situating explanations of economic phenomena in relation to rationality has increasingly become the touchstone by which mainstream economists identify themselves and recognize each other. This is not so much a question of adherence to any particular conception of rationality, but of taking rationality of individual behavior as the unquestioned starting point of economic analysis.

Foley (2003, p. 9) went on to argue that

The concept of rationality, to use Hegelian language, represents the relations of modern capitalist society one-sidedly. The burden of rational-actor theory is the assertion that ‘naturally’ constituted individuals facing existential conflicts over scarce resources would rationally impose on themselves the institutional structures of modern capitalist society, or something approximating them. But this way of looking at matters systematically neglects the ways in which modern capitalist society and its social relations in fact constitute the ‘rational’, calculating individual. The well-known limitations of rational-actor theory, its static quality, its logical antinomies, its vulnerability to arguments of infinite regress, its failure to develop a progressive concrete research program, can all be traced to this starting-point.

More recently Edward J. Nell and Karim Errouaki (2011, Ch. 1) argued that:

The DNA of neoclassical economics is defective. Neither the induction problem nor the problems of methodological individualism can be solved within the framework of neoclassical assumptions. The neoclassical approach is to call on rational economic man to solve both. Economic relationships that reflect rational choice should be ‘projectible’. But that attributes a deductive power to ‘rational’ that it cannot have consistently with positivist (or even pragmatist) assumptions (which require deductions to be simply analytic). To make rational calculations projectible, the agents may be assumed to have idealized abilities, especially foresight; but then the induction problem is out of reach because the agents of the world do not resemble those of the model. The agents of the model can be abstract, but they cannot be endowed with powers actual agents could not have. This also undermines methodological individualism; if behaviour cannot be reliably predicted on the basis of the ‘rational choices of agents’, a social order cannot reliably follow from the choices of agents.

Empirical critiques

In their 1994 work, Pathologies of Rational Choice Theory, Donald P. Green and Ian Shapiro argue that the empirical outputs of rational choice theory have been limited. They contend that much of the applicable literature, at least in political science, was done with weak statistical methods and that when corrected many of the empirical outcomes no longer hold. When taken in this perspective, rational choice theory has provided very little to the overall understanding of political interaction - and is an amount certainly disproportionately weak relative to its appearance in the literature. Yet, they concede that cutting-edge research, by scholars well-versed in the general scholarship of their fields (such as work on the U.S. Congress by Keith Krehbiel, Gary Cox, and Mat McCubbins) has generated valuable scientific progress.

Methodological critiques

Schram and Caterino (2006) contains a fundamental methodological criticism of rational choice theory for promoting the view that the natural science model is the only appropriate methodology in social science and that political science should follow this model, with its emphasis on quantification and mathematization. Schram and Caterino argue instead for methodological pluralism. The same argument is made by William E. Connolly, who in his work Neuropolitics shows that advances in neuroscience further illuminate some of the problematic practices of rational choice theory.

Sociological critiques

Pierre Bourdieu fiercely opposed rational choice theory as grounded in a misunderstanding of how social agents operate. Bourdieu argued that social agents do not continuously calculate according to explicit rational and economic criteria. According to Bourdieu, social agents operate according to an implicit practical logic—a practical sense—and bodily dispositions. Social agents act according to their "feel for the game" (the "feel" being, roughly, habitus, and the "game" being the field).

Other social scientists, inspired in part by Bourdieu's thinking have expressed concern about the inappropriate use of economic metaphors in other contexts, suggesting that this may have political implications. The argument they make is that by treating everything as a kind of "economy" they make a particular vision of the way an economy works seem more natural. Thus, they suggest, rational choice is as much ideological as it is scientific, which does not in and of itself negate its scientific utility.

Critiques on the basis of evolutionary psychology

An evolutionary psychology perspective suggests that many of the seeming contradictions and biases regarding rational choice can be explained as being rational in the context of maximizing biological fitness in the ancestral environment but not necessarily in the current one. Thus, when living at subsistence level where a reduction of resources may have meant death it may have been rational to place a greater value on losses than on gains. Proponents argue it may also explain differences between groups.

Critiques on the basis of emotion research

Proponents of emotional choice theory criticize the rational choice paradigm by drawing on new findings from emotion research in psychology and neuroscience. They point out that rational choice theory is generally based on the assumption that decision-making is a conscious and reflective process based on thoughts and beliefs. It presumes that people decide on the basis of calculation and deliberation. However, cumulative research in neuroscience suggests that only a small part of the brain's activities operate at the level of conscious reflection. The vast majority of its activities consist of unconscious appraisals and emotions. The significance of emotions in decision-making has generally been ignored by rational choice theory, according to these critics. Moreover, emotional choice theorists contend that the rational choice paradigm has difficulty incorporating emotions into its models, because it cannot account for the social nature of emotions. Even though emotions are felt by individuals, psychologists and sociologists have shown that emotions cannot be isolated from the social environment in which they arise. Emotions are inextricably intertwined with people's social norms and identities, which are typically outside the scope of standard rational choice models. Emotional choice theory seeks to capture not only the social but also the physiological and dynamic character of emotions. It represents a unitary action model to organize, explain, and predict the ways in which emotions shape decision-making.

The difference between public and private spheres

Herbert Gintis has also provided an important criticism to rational choice theory. He argued that rationality differs between the public and private spheres. The public sphere being what you do in collective action and the private sphere being what you do in your private life. Gintis argues that this is because “models of rational choice in the private sphere treat agents’ choices as instrumental”. “Behaviour in the public sphere, by contrast, is largely non-instrumental because it is non-consequential". Individuals make no difference to the outcome, “much as single molecules make no difference to the properties of the gas" (Herbert,G). This is a weakness of rational choice theory as it shows that in situations such as voting in an election, the rational decision for the individual would be to not vote as their vote makes no difference to the outcome of the election. However, if everyone were to act in this way the democratic society would collapse as no one would vote. Therefore, we can see that rational choice theory does not describe how everything in the economic and political world works, and that there are other factors that of human behaviour at play.