Cognitive Science: An Introduction/Emotion

It's difficult to define what emotions are, but in general they share some characteristics. First, they are automatic processes. That means that you don't choose to be emotional or not, for the most part. Emotions kind of feel like they happen to you, and might choose to deal with them. You don't choose to be angry. At best, you can choose to do something that you expect will make you angry. From an evolutionary perspective, emotions are like the automatic settings on a camera, in that they tend to produce behavior that is generally adaptive, without requiring deliberative thought [1]. Emotions also tend to have "action tendencies." That is, emotions are not just feelings, but they tend to ready the body for certain kinds of actions. Fear, for example, prepares you for fleeing or fighting by raising blood pressure, increasing focus, etc. Even the facial expressions of some emotions can be related to their evolutionary function. For example, the fear facial expression expands the nasal cavity and widens the eyes, enhancing smell and enlarging the field of view. The disgust expression crinkles up the face, reducing the chance of a pathogen entering the body through the eyes or nose.

Other things we associate with emotions are vocal expressions, physiological changes (such as an increased heart rate), subjective feelings of emotion, readiness for particular actions, and psychosocial functions.[2]

Evolutionary psychology might define emotions this way: "Emotions are a type of program, instantiated in our neural circuitry, that coordinates elements of our psychology and physiology in response to a recurring ancestral situation in a manner that tended to increase the chances of survival and reproduction."[3]

Emotions are distinguished from "moods" in that moods are longer lasting and tend to build up over time.[4]

Emotions vary widely in how they are implemented in the brain. This is because emotions are evolutionarily old. Getting away from humans for a moment and just talking about mammals in general, they all have basic emotional circuitry for what might be described as systems or modes by Jaak Panksepp: SEEKING/desire, RAGE/anger, FEAR/anxiety, LUST/sexual, CARE/maternal, GRIEF/separation, and PLAY/rough-and-tumble. [5].

Reasoning, on the other hand, has a fair degree of unity, depending critically on the dorsolateral prefrontal cortex (DLPFC)[6].

Emotions also help us know what is important to consider. Information without affect does not get used in decision making. This was made famous by Phineas Gage, who had trouble with many simple decisions of daily life, such as choosing a shirt in the morning (TK make sure this is true).

Primordial EmotionsEdit

Some emotions are very basic. These include thirst, the hunger for food, specific minerals, or air, pain, sexual arousal and orgasm. These are found across many species and are genetically encoded. Their function is to ensure homeostasis in the organism, and are usually triggered by internal perceptions (interoception). [7]

Basic EmotionsEdit

Some emotions have become known as the "basic emotions," because they appear in all human cultures: joy, anger, fear, surprise, disgust, and sadness. More than that, they even have the same facial expressions. When you show people pictures of people expressing these basic emotions, people anywhere in the world can correctly recognize them. Many of these facial expressions can also be made by other mammals, which is why you can often tell when a cat is angry. However, many emotions, such as jealousy, have no facial expressions.[2] Of course, there are also physiological processes at work that also contribute to homeostasis. Those that are emotional presumably need to influence the decision-making systems for organism's behavior.

Facial ExpressionsEdit

Facial expressions are coordinated patterns of muscle movements that seem to be triggered by particular brain areas--and if there is a dysfunction in that brain area, a person might be unable to make a facial expressions.[2]

Facial expressions occur very quickly--sometimes within milliseconds of the stimulus that caused them.[2]

Facial expression is tightly linked to emotion, as many emotions, though not all, are communicated with others through facial expression. Although the basic emotions (joy, sadness, fear, surprise, and anger) are well-known, combinations of these can be expressed by humans and correctly interpreted. 21 of these categories have been found, including "happily surprised."[8]

Appraisal TheoryEdit

Although it often feels as though our emotions are directly caused by events in the environment, appraisal theory holds that emotions are the result of our appraisals of them.

Computer Simulations and Models of EmotionEdit

The world has become accustomed to man-made machines (computers) that are responsible to do tasks according to its programmer. However, with technological advancements, machines mimicking human emotions have become a mysterious, controversial phenomenon throughout the years. How does one replicate complex processes caused by stimuli, and recreate a frame of mind through programming a machine?

Practically, it is impossible to account for every “if” and circumstance assessed by humans, in order for the ‘perfect’ cognitive model to be established. In other words, ‘emotion’ is defined by several factors that influence reactions from humans and animals alike, which is crucial to the programming process in a machine. Some factors include high-level programming languages, numerous and thorough experimentation, and physiological and biological consideration.[9]

Artificial intelligence, also known as AI, have been able to do many human-like tasks, such as smiling and laughing. This has been able to occur through basic pre-existing technology like programmed motors and audio systems. However, how are more complex human emotions such as jealousy or fear, which are often a buildup of multiple emotions and feelings, able to be programmed within AI? How does one even start on designing a cognitive model that replicates such intricate emotions?

Quite simply, scientists have concluded that there are vast differences between replicating and feeling emotions.[10] In other words, we can program AI to “stretch the corners of [their] mouth laterally and hold for 10 seconds”[11] but this lacks the cognitive model that one truly needs to display emotions and instead, we associate smiling to happiness, thus, people assume that the robot is happy after doing that respective action. When replicating emotions, stereotyping human reactions to emotions is common as the complexity of feeling, is far too large of scope to completely attain.

It is important to understand that cognitive machines consist of generalized programming to express specific emotions that humans can express in various ways. Identity and agents of socialization cannot be achieved with AI, as everything is predetermined through programming.[12] Without the marked-up tabula rasa in consideration (full of experiences that make an individual who they are), true models of emotions cannot be felt nor expressed and certainly not recreated with today's technology surrounding computer simulations.

The Individual EmotionsEdit

Some scholars have defined emotions as though they were points in an abstract space of dimensions, such as valence (good or bad), arousal (high or low) and activity. But many see each emotion as being distinct. How many emotions are there? Different theories have different numbers, but most agree on these: happiness, fear, anger, sadness, and disgust. Others include interest, surprise, contempt, guilt, embarrassment, regret, and jealousy. This book does not take a stand on exactly how many emotions there are. Rather, each proposed emotion will be discussed, along with some science that investigates it.


Awe is thought of as a mixture of fear and delight.


Joy is an emotion of intense happiness and elation. The emotion is considered to express more than mere physical enjoyment, but great psychological satisfaction[13] . The pursuit of joy is instinctual as can be observed in human infants [14]. The psychological importance of joy and its pursuit can yield mental resilience facing challenges and obstacles. Similar to physical nutrition, the input of joyful experiences can provide psychological sustenance throughout years of mental hardship [15]. People who have few experience of joy or hope of future happiness tend to be less emotional resilient and psychosocially persistent [16].

Joy is the emotional expression some positive evaluation. Concerning its biological markers, joy results in a flood of the neurotransmitters dopamine and norepinephrine[17]. Despite its universal appearance throughout cultures, its experience can differ depending on cultural context and circumstances[18].

In general, a "happy person" reports higher life satisfaction and greater appreciation of small pleasurable moments. Joy is correlate with overall positive emotions, while still remaining susceptible to negative emotions. A relatively happy person may less intense negative emotions while reporting less negative evaluation of an event. This idea can also be confirmed in Waude's survey of positive emotions. According to Waude, joy is a subjective experience that depends on the subjective interpretations of an experience or event [19].

Evidence suggests that the social aspect of discussing positive experiences contributes to an individual’s joy. Research by Nathaniel Lambert of Brigham Young University and his colleagues shows that, while people experience positive emotions every day, positive impacts peaks when participants share their positive experiences and partners positively respond[20]. Lambert’s research indicates that verbally expressing positive experiences leads to higher levels of joy, overall life satisfaction and general vitality.

Relationship between joy and other positive emotionsEdit

While happiness and joy are both positive emotions, they are often conflated. Happiness is more often reported in regards to material and worldly satisfaction, while joy is the more often reported in terms of life satisfaction and psychological fulfillment [21]. Joy is more likely to be cultivated inwardly instead of related to individual events. Happiness is often triggered externally by people, things, places, and events. While happiness may bring a surge of transient positive emotions, joy is a long-term sense of satisfaction achieved by connecting moments of happiness into meaning. Research concerning neural pattern in the ventral striatum predict higher levels of joy in those cultivating positive emotions such as kindness and compassion [22]. Subjects shown to have higher levels of joy also reported more enthusiastic and alert emotional states.

Positive and negative effects of joyEdit

Joy brings benefits to people not only mentally, but also physically. Joy has benefits for one’s brain, circulatory system and autonomic nervous system [23]. When a person experiences joy, the brain increases its releases of serotonin and dopamine. People with clinical depression often have lower serotonin levels. Joy also affects some aspects of autonomy, such as sweating, body temperature, and metabolism. According to research, good health is correlated with positive mental state. The act of smiling increases serotonin and endorphin release in the brain. Endorphins act as natural painkillers. Positive mental states are correlated with beneficial biological effects such as a strengthened immune system, lower blood pressure, and a lower risk of heart disease[24]. The immune systems response to positive affect includes the increase of white blood cells and antibodies. Some psychologists have raised the question whether too much happiness can result in negative effects. Evidence suggests that happiness may not be unequivocally beneficial, and may warrant experiencing in moderation. Studies suggest that very high levels of positive emotions are predictive of risky behaviors, such as overeating, excess alcohol, and sexually promiscuity [25].

Joy and societyEdit

While there exists many potential causes of for joy, researched appears to converge on the most significant cause is a person’s community. The 7th World Happiness Report [26] found that a person’s social environment, including social background and political system, greatly affects levels of personal joy. This data strongly suggests that the connections between people and the institutions they share are significant contributor to their joy. Those who live in large cities tend to be more socially isolated, which negatively affects their psychological well-being. Positive psychologists suggest a further social dimension to happiness: the feeling of commitment and participation in life and society [27]. Research indicates that this marker of happiness corresponds with individual self-report and can diminish with age as engagement with society can decline.

Neuroscience of JoyEdit

Humans possess an extensive neurological reward circuitry, all of which derive from a rather rudimentary ‘liking’ mechanisms that cause pleasure reactions [28].  These span across brain regions, from deep in the subcortical areas of the nucleus accumbens, ventral pallidum and brainstem, to the neocortex, including the oribitofrontal cortex, the cingulate cortex, the medial prefrontal cortex, and the insular cortex.  However, only the nucleus accumbens and the ventral pallidum have been proven to have a causal role in the pleasure experience. Neurological research has provide support for Basic Emotion Theory, which postulates that each emotion is associated with a signature neural correlate in the brain [29]. Happiness is consistently associated with nine clusters of activity, most of which occur in the right superior temporal gyrus. The prefrontal cortex (PFC) plays an important role in both happy and unhappy states. The higher activity in the left middle frontal gyrus is predictive of happiness in participants.  This region is also associated with characteristics to do with resilience; i.e., avoiding and/or moving through difficult emotions[30].  


Disgust seems to be an emotion that humans have at birth, though not everything that disgusts adults disgusts newborns--for example, fecal matter doesn't seem to disgust children until they are 1 or 2 years of age.[31] It is theorized to have been evolved in order to keep us from touching, eating, and having sex with things that we shouldn't. There is a great deal of research on disgust, partially because it's so easy to generate it in a laboratory setting. In contrast, it's much harder to make somebody really angry or scared. Disgust seems to be elicited by rotten or tainted food [32], bodily products (mucus, urine, etc.) [33], people who are ill, unfortunate, or morally tainted [34], death [35], mortality [36], bad hygiene [37], body envelope violations (things entering the body)[35], and certain aspects of sex (such as incest).

Although some scholars have theorized that humans are the only natural creatures with a sense of disgust, there is some evidence that lemurs display disgust behaviors.[38]

We should be careful not to identify the emotion of disgust with the way the word "disgust" is used in English. Sometimes people say they're disgusted when they're really angry. If someone doesn't like carrots, they might say that carrots are "disgusting," but they probably don't really. If you touch a carrot to other food, it doesn't contaminate it, like doing the same thing with a cockroach would. Some say that "gross" is a word that better targets the actual feeling.[31]

Not all food aversion is based on disgust. For example, one might avoid peanuts because of an allergy, but admit to liking peanuts. They don't avoid them because they find them disgusting. However, having a nauseous reaction to a food often makes people feel a disgust reaction to it afterward.[31]

In modern humans, we also learn to attach behaviors to the emotion of disgust, metaphorically, so that disgust has become an important moral emotion.[3] So if we feel disgust in three different domains, then why do we think of them as being a single emotion?

One reason is that we can get cross-over. For example, if there is a bad smell in the room, people will make harsher moral judgments. People judge obese people more harshly for "disgust" related crimes than not.


Elevation is a positive emotion theorized to be associated with perceptions of moral goodness and divinity. It involves feelings of warmth, and conscious desires to help others. Physiologically, there is often a calm feeling, with low physiological arousal (unlike admiration). It is possible that oxytocin is released.[39]


The Neuroscience of FearEdit

Fear is an emotion felt when one encounters a stimulus that they perceive to be unknown and/or alarming. This stimulus triggers a cascade of neurological events throughout the body that lead to the behaviors of fight or flight[40]. The stimulus can include fear of the dark, snakes, or even the fear of numbers, yet each fear triggers common neural pathway and circuitry throughout the nervous system. When these fears begin to create a positive feedback loop, it magnifies our stimulus response loop, to become self-reinforcing phobias. Phobias are defined as irrational or disproportionate fears that interfere with regular, everyday cognitive processes. This disruption in neurological and cognitive systems can then cause further co-morbidity and maladaptive coping mechanisms. There exists different therapies to help in coping with fears, and to make beneficial changes in our neural reactions to unknown and/or alarming stimuli.

Fear is defined as a negative emotional state that we feel when a fearful stimulus is presented to us. This feeling of fear triggers a biological effect that causes changes in the brain, which changes signalling in our endocrine system. When the neurological signalling of fear is over expressed, we develop a chronic fear called a phobia[41]. These fears and phobias can be treated using methods such as pharmacological treatments, and therapeutic techniques like cognitive behavioral therapy.

Neurological mechanisms of fearEdit

When no aversive stimulus is presented to the brain, the frontal cortex is in a default state of excitation. When a potentially fearful stimulus is presented, the frontal cortex assesses the threat, and once perceived, the amygdala inhibits the prefrontal cortex [42]. This inhibition occurs through the transmission of the neurotransmitter Gamma amino butyric acid (GABA)[43]. After GABA has bound to the receptor it inhibits the post synaptic potential (IPSP) on the prefrontal cortex [44]. The amygdala then activates the two pathways of the sympathetic nervous system, the hypothalamic pituitary adrenal (HPA) axis and the sympathomedullary (SAM) pathway.

Neuroscience of phobiasEdit

Fears can develop into disproportionate and irrational phobias that interfere with normal cognitive functions. This occurs by the fear response undergoing a positive feedback loop, which magnifies the stimulus response loop. Phobias are a specific kind of fear classified under anxiety disorders, yet they remain two distinct phenomena. Fear is the response of a present situation, while anxiety is the response to an impending event. In phobias, the brain’s response to fears is different than the regular fight or flight response[45].

The nature phobias’ difference lie within the amygdala, as the amygdala is overly sensitized to cues associated with the fearful stimulus[46]. There is a reduction in the habituation to fearful cues=. This causes an exaggerated response in the brain to a specific fearful cue. The sensitized amygdala acts synergistically with the production of cortisol from the HPA axis. This can have detrimental neurological effects considering that evolutionarily, humans are not designed for a prolonged fight or flight stress response[47]. The fear response is meant to be a solution to a temporary threat. The constant production of cortisol creates problems when binding long-term to the hippocampal corticosteroid receptors. When cortisol bombars these receptors it inhibits neurogenesis in the hippocampus [48]. This will create a positive feedback loop in the brain, causing the HPA axis to remain active, further disturbing cognition. A constant feeling of fear is what creates this positive feedback loop. This increases the chances of developing further phobias and mental illnesses like depression. This is common in those with anxiety disorders such as phobias[49].


The first pathway that becomes active is the SAM pathway. An excitatory signal is sent through the spinal chord and onto the adrenal medulla, which releases catecholamines like epinephrine and norepinephrine[50]. The HPA axis is initiated when the amygdala excites the hypothalamus using glutamate[51]. The hypothalamus then releases corticotrophin releasing hormone (CRH) onto the anterior pituitary gland, which releases adrenocorticotropic releasing hormone (ACTH) into the bloodstream that goes into the adrenal cortex, finally causing the release of cortisol[52]. The products of these two pathways is to cause an increase in heart rate, sweat, and readies glucose storage so that metabolic energy is available.

Therapeutic treatmentsEdit

There are various psychological and cognitive methods to overcoming fear. These therapies create reliable neurological effects. Cognitive behavioral therapy are considered to yield the greatest beneficial effects within the ventromedial prefrontal cortex. The ventromedial prefrontal cortex is responsible for extinction of the fear response through inhibiting the amygdala’s response to fearful cues or stimuli[53]. Other therapies have shown to effect the ventral prefrontal cortex during early extinction, and also may predict the therapy’s effectiveness [54], as the activity of glutamate neurotransmission increases with the application of therapy[55].

Pharmacological treatmentEdit

Pharmaceutical methods. Typically, the drugs of choice are benzodiazepines or selective serotonin reuptake inhibitors (SSRI). These drugs both can treat feelings of fear and anxiety, yet by way of different means. Benzodiazepines act on the receptor for the neurotransmitter GABA, antagonizing the uptake of GABA on the post synaptic neurons. SSRIs will act by preventing the reuptake of serotonin into the presynaptic neuron, thus increasing the amount of serotonin on the post synaptic neuron[56]. Both drugs can produce feelings of relaxation and alleviation of fear, although it lacks precise reliability.


The feeling of being interested in something has been argued to be an emotion distinct from the others, though not all scholars agree.[2]


Pride is a positive feeling about oneself or one's group.


"Fiero," an Italian derived word with no true English dictionary definition, describes a complex emotion expressed after the accomplishment of a difficult task.[57] It is a feeling that people chase, similar to the thrill sought after while riding roller-coasters.[58] Fiero acts as a prominent emotion in our everyday lives, providing academic and career motivation, driving us towards our goals and unconsciously pushing us towards success. Fiero is a concept commonly used in game development and gamification, which is “the process of applying game design theories to everyday situations”.[59] Utilizing human psychology and what is known about the brain allows businesses to build company strategies around a reward and achievement based system. Fiero is all around us, whether it is achieving a sought after promotion at work or receiving a high mark on your academic project, the elated feeling we seek is the same.

The feeling of fiero appears to be associated with the activity of five neurotransmitters; Dopamine, Oxytocin, Serotonin, Endorphins, and Epinephrine (Adrenalin). Dopamine is responsible for many tasks inside our brains, but in this case, it is an important chemical messenger for motivation and reward.[60] Dopamine was previously thought to be released after the completion of a task, providing pleasure, but it was discovered that it actually is released in anticipation of achievement or reward, providing motivation and satisfaction throughout the execution of a task.[61] Serotonin, similar to Dopamine, has a variety of functions within the body. It is a mood regulator. High levels of serotonin cause positive feelings, where low levels cause depressive feelings. Actively released serotonin creates the feeling of calmness, self-confidence and happiness.[62] The Serotonin molecular formula is C10H12N2O. Oxytocin is released through development of social interaction and excitement. This neurotransmitter allows for the creation of emotional bonds and meaningful connections. [63] Its molecular formula is C43H66N12O12S2. Epinephrine, more commonly called ‘Adrenalin’, is released in moments of danger, developing the excitement sensation. This neurotransmitter acts as an enhancer, and often is released along with other neurotransmitters. It allows one to feel a rush or thrill after an achievement or reward, which is what drives this topic. [64]

We have defined the feeling of fiero as pride experienced after overcoming a difficult task. The chemicals described above work in unison to build this elated feeling of accomplishment and allow one to understand the neuroscience behind the emotion. As game technology, graphical design and plot structures advance, game developers understand that they must incorporate triggers to these primary neurotransmitters in their games. The feeling of fiero is sought after as a gamer, whether they are aware of it or not.

A game developing team has an large amount of variations or strategies they can choose in order to create an exciting, addictive game. Studies have shown that fiero is drawn from the concept of “hard fun”, having that as the underlying concept is key. Including dopamine triggers like exploration campaign modes and high-quality graphic designs could be important. Adding social aspects to the development of the game like in-game chats will allow for the release of the bond transmitters, Oxytocin and Serotonin. Understanding that these neurotransmitters that make life pleasurable are directly linked to parts of some of the highest rated games ever produced and sold. Fiero is an elusive and thrilling feeling, and its connection to the virtual world is what allows it to grow.[65]

It is unknown whether fiero is a separate emotion, or the same feeling we call "pride," but specific to pride caused by achievement.


Risk, too, has been identified as a feeling.[66]


Shame is often distinguished from guilt in the following way: guilt is feeling bad for what you have done, and shame is feeling bad for what you are. In particular, people can feel shame for things done to them. For example, if someone steals your clothing and you have to walk home naked, you might feel shame but not guilt.

Other primates have behaviors similar to humans behavioral correlates to shame, including slumped shoulders, crouching, downcast gaze, and small posture. The intention seems to be to make oneself look unimposing and small.[67]

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