Exam 1: Emotions

Question 1

emotions vs mood vs feeling

Answer 1

emotion: immediate, intense responses to specific stimuli involving physiological changes, expressive behaviors, and subjective experiences
mood: diffuse, long-lasting emotional states
feeling: the subjective experience of emotional states shaped by current emotions, memories, etc.

Question 2

what is affect?

Answer 2

refers to the subjective feeling, tone, or quality of an experience (encompasses both emotions and moods)

Question 3

what is the circumflex model of emotion?

Answer 3

valence (positive or negative) and arousal (high or low) are used to measure emotions with opposite emotions being on opposite poles for valence and activation

Question 4

what was Charles Darwins theory of emotion?

Answer 4

he believed that animal emotions are homologs for human emotions and that there are a set of basic emotions that present across species

Question 5

what is the James-Lange theory of emotion?

Answer 5

emotions occur as a response to a specific physiological reaction (i feel afraid because my heart is pounding, i feel sad because i cry)

Question 6

what is the Cannon-Bard theory of emotion?

Answer 6

they observed that despite severing connections between emotional responses and physiological responses animals still had normal emotional responses, from this they concluded that emotions and physiological responses occur simultaneously (my heart pounds and i feel afraid)

Question 7

what is the Schachter-Singer theory of emotion?

Answer 7

we must label the physiological response in order to generate an emotion, individual perception and thoughts about a stimulus can influence the type of emotion (my pounding heart means i’m afraid because i interpret the situation as dangerous)

Question 8

what is Schachter and Singer’s classic study?

Answer 8

they hypothesized that if an individual experiences unexplained physiological arousal they will label their emotional state based on available environmental and cognitive cues, to test this participants were given epinephrine and a confederate would then act either euphoric or angry near them, participants who did not know they got epinephrine were more likely to label their feelings based on the environmental cues than those who knew the side effects of epinephrine

Question 9

what theory of emotion is most supported by scientific evidence?

Answer 9

James-Lange theory is most closely supported, Antonio Damasio proved that each basic emotion produces a distinct pattern of neuronal reponse and physiological changes that occur before they are interpreted as an emotion

Question 10

what is the Yerkes-Dodson law?

Answer 10

the optimal amount of arousal for performance is an inverted U-shaped curve where too little arousal leads to poor performance (boredom, lack of motivation) but too much arousal leads to poor performance as well (stress, anxiety)

Question 11

what is the Papez circuit of emotions?

Answer 11

says that emotional experiences regardless of if they come from the thinking or feeling circuits are a function of activity in the cingulate cortex

Question 12

what is the ‘feeling’ stream/downstream path of the Papez circuit?

Answer 12

represents the rapid generation of emotional states and responses
thalamus -> hypothalamus -> anterior thalamus -> cingulate cortex

Question 13

what is the ‘thinking’ stream /upstream path of the Papez circuit?

Answer 13

represents the analysis of sensory information and formation of thought and memories
thalamus -> sensory cortex -> cingulate cortex -> hippocampus -> hypothalamus

Question 14

what is MacLean’s limbic system?

Answer 14

suggests the brain has three distinct layers that correspond to different brain structures that govern distinct types of behavior, these layers are the basal ganglia (reptillian brain), limbic system (paleomammalian brain), and the neocortex (neomammalian brain)

Question 15

what makes up the limbic system and what does it do?

Answer 15

limbic system regulates emotions and social behaviors as well as memory formation and stress response and is made up of the hippocampal formation, thalamus, hypothalamus, cingulate cortex, amygdala and prefrontal cortex

Question 16

what is Kluver-Bucy syndrome?

Answer 16

a syndrome caused by removal of temporal lobes including the amygdala, symptoms include compulsive eating and sexuality, loss of normal fear responses, difficulty recognizing objects, oral fixation

Question 17

what are the sub-areas of the amygdala and what do they contain?

Answer 17

basolateral amygdala (BLA): cortex-like structure, 80% glutamatergic, 20% GABAergic interneurons, recieves input from sensory systems and allows them to pass through
central amygdala (CEA): striatum-like structure, mostly GABAergic neurons that project to other areas of the brain to mediate defensive behaviors, output region for the expression of innate emotional responses and their physiological processes

Question 18

what does a normal fear response in the brain look like?

Answer 18

amygdala is activated during acquisition and extinction of fear conditioning, amygdala is also triggered by seeing fearful faces of other people, the amygdala response to fearful and neutral faces rapidly declines with each run as the brain adapts

Question 19

what does amygdala lesions in humans lead to?

Answer 19

selective amygdala damage does not usually lead to Kluver-Bucy symptoms until more extensive bilateral damage is done, amygdala damage does impair recognition and processing of fearful facial expressions (patient SM)

Question 20

what role do the amygdala and hypothalamus play in anger?

Answer 20

lesioning of the amygdala or stimulation has been used to treat severe, refractory aggression in some patients, stimulation of the hypothalamus has been shown to induce sham rage

Question 21

what are the three sections of the hypothalamus responsible for?

Answer 21

anterior region: producing oxytocin and vasopressin
medial region: associated with producing various hypothalamic-releasing hormones and controlling numerous motivated behaviors
posterior region: involved in thermoregulation and contributes to processes related to memory and emotions

Question 22

what is the physiological process for aggression in humans?

Answer 22

sensory information is processed by the thalamus and then integrated by the hypothalamus and amygdala to promote aggressive actions, top-down projections of the prefrontal cortex to these brain regions play an important role in controlling aggressive actions

Question 23

what is the physiological process for aggression in rodents?

Answer 23

olfactory sensory information is processed by the olfactory bulbs and relayed to the core aggression circuit for integration, innate attacks are mediated through the hypothalamic projection to the PAG

Question 24

how does the anterior and lateral hypothalamus play a role in Delgado’s sham rage?

Answer 24

anterior hypothalamus: deep brain stimulation of the anterior hypothalamus in cats produced sham rage but the reaction lacked the full emotional and behavioral components of true rage
lateral hypothalamus: stimulation of the lateral hypothalamus (or periventricular gray matter) elicited true rage in cats, this produced more complex and directed agressive behaviors like attacking other animals

Question 25

how does the pre-frontal cortex effect rage?

Answer 25

the PFC regulates emotional responses and leads to impulsivity, immaturity, and a loss of control when damaged, murderers were shown to have reduced glucose metabolism in the prefrontal cortex bilaterally which suggests that this abnormality may predispose to violence through effects on emotional regulation, impulse control, and social information processing, phineas gage is an example of this

Question 26

what role does dopamine play in social isolation/sadness?

Answer 26

optogenetic activating of DA neurons in a social context promotes social interaction while activating these neurons in the absence of a social conspecific is aversive, these DA neurons from the dorsal raphe almost exclusively innervate the amygdala and regulate different behaviors depending on their downstream target, for instance, DRN DA neurons projecting to the CeA
promote sociality, while those projecting to the posterior basolateral amygdala regulate negative affective state

Question 27

what role do opioids play in social isolation/sadness?

Answer 27

social isolation may be processed by pain-sensing brain regions, suggesting a neurobiological link between social and physical pain, acute social isolation may mimic a withdrawal-like state characterized by reduced endogenous opioid (endorphin) release, this withdrawal-like state may evolutionarily function to motivate individuals to seek social contact

Question 28

how do we study love?

Answer 28

with voles, prarie voles are monogamous and form pair bonds that last a lifetime but montane voles are asocial and do not form pair bonds

Question 29

what amino acid peptides make up ‘love’ and what do they do?

Answer 29

oxytocin (oxytocin is released during reproduction and also causes uterine contractions during labor and the milk letdown reflex after birth) and vasopressin (vasopressin plays a role in regulating salt concentration in the blood by acting on the kidneys to promote water retention and decrease urine production)

Question 30

what role does the hypothalamus play in ‘love’?

Answer 30

magnocellular neurosecretory cells send axons from the hypothalamus down to the pituitary gland, the magnocellular neurons in the hypothalamus synthesize and
release oxytocin and vasopressin into the blood stream, oxytocin fibers originating from paraventricular neurons of the hypothalamus (specifically from the PAG) project to the nucleus accumbens, medial amygdala, and prefrontal cortex, vasopressin projections in the brain originate from extrahypothalamic neurons in the medial amygdala and bed nucleus of the stria terminalis (BNST), these projections are primarily directed towards the lateral septum

Question 31

what does oxytocin and vasopressin receptor expression in prarie voles look like?

Answer 31

monogamous prairie voles have higher densities of oxytocin receptors in the nucleus accumbens compared to non-monogamous vole species, they also have higher densities of
vasopressin 1a receptors (V1aR) in the ventral pallidum, despite similar receptor densities, oxytocin seems more important for pair bonding in females, while vasopressin is more critical in males

Question 32

is love an addiction?

Answer 32

yes, studies show that mating results in an increase (~50%) in extracellular dopamine in the nucleus accumbens of
female voles, this increase in dopamine is crucial for pair bond formation

Question 33

how does partner preference develop?

Answer 33

even without mating stimulation of D2 receptors can induce partner preferences, the ability of D2 agonists to stimulate partner preference relies on the concurrent activation of oxytocin receptors in the NAc

Question 34

what does vasopressin do in male voles brains?

Answer 34

V1aR receptors (overexpression) in the prairie vole ventral pallidum facilitate pair-bond formation and V1aR antagonist in the ventral palidum reduce pair-bond formation, the admission of vasopressin has been shown to enhance paternal behaviors,

Question 35

where is ‘love’ located in the brain?

Answer 35

from people who reported being in love activation was observed in areas associated with the brain’s reward and motivation systems, specifically the ventral tegmental area (VTA) and the caudate nucleus, decreased activity of serotonin contributes to a lover obsessive thinking

Question 36

what is optogenetics?

Answer 36

a technique that uses the combination of light and genetic engineering to control the activity of a cell, requires surgical implantation which could cause tissue damage

Question 37

what is chemogenetics?

Answer 37

a technique that uses chemically engineered molecules (receptors) and designer drugs (activators) to alter neural activity

Question 38

what is the conditioned place preference (CPP) model?

Answer 38

one context is consistently paired with drug administration, while the other is paired with a neutral vehicle (usually saline), subsequently, during a drug-free test phase, the animal is allowed to freely choose between the drug-paired and vehicle-paired contexts, a significant increase in preference for the drug-paired context, compared to the vehicle-paired context, is interpreted as evidence of the drug’s rewarding properties

Question 39

what is the agression conditioned place preference model?

Answer 39

in this adapted version, male CD-1 mice, known for their aggressive tendencies, are used as the experimental subjects, the procedure begins with a screening phase using the resident-intruder test to identify mice that exhibit aggressive behavior in one context, the CD-1 mouse encounters a subordinate C57BL/6J intruder mouse, allowing for aggressive interactions, the other context serves as a control, where no intruder is present, after repeated pairings of aggression with one context and no aggression with the other, a test phase occurs, if the mouse spends significantly more time in the context previously associated with aggressive encounters, it suggests that the aggressive experience was rewarding for the animal

Question 40

what does the self-administration model of aggression tell us?

Answer 40

the nucleus accumbens major projection neurons are GABAergic and express dopamine receptor 1 and/or dopamine receptor 2 (D1 and D2) and generally exert opposite effects on target brain regions, aggressive behavior and exposure to aggression-associated contexts increase extracellular dopamine levels in the NAc

Question 41

how does fear play a role in PTSD?

Answer 41

PTSD has a traumatic memory at its core, the memory carries intense emotional charge, often triggering strong fear, anxiety, or horror when recalled, similar sensory elements can trigger flashbacks, this causes an overgeneralized fear response and avoidance behaviors, fear conditioning takes place

Question 42

what are the four types of PTSD symptoms?

Answer 42

intrusive memories, avoidance, negative changes in thinking and mood, and changes in physical and emotional reactions

Question 43

what four brain regions play a role in fear learning?

Answer 43

amygdala: the amygdala processes and stores emotional aspects of traumatic memories
prefrontal cortex: the prefrontal cortex regulates emotional responses and can modulate fear memories in the amygdala
hippocampus: the hippocampus encodes contextual information and supports memory consolidation and retrieval
infralimbic prefrontal cortex: plays a role in extinction learning by inhibiting reconsolidation of memories

Question 44

consolidation vs reconsolidation

Answer 44

consolidation is the process by which newly formed memories are stabilized and stored in the brain for long-term retention, emotional arousal and stress hormones can enhance memory consolidation particularly for emotionally significant events
reconsolidation refers to processes that restore memories to a more permanent form after it has been retrieved, used to modify or update memories for the first few hours after retrieval