Neurobiology of Emotions

Question 1

what is an emotion?

Answer 1

Physiological Arousal
Anatomical Level
Hormonal Level

Expressive Behaviours
Behavioural Level

Conscious Experience
Cognitive Level

Question 2

what did Darwin believe about emotions?

Answer 2

emotions evolved from behaviors:
(1) what an animal would do next in a given situation
(2) behaviors that are advantageous to the animal
“fight or flight” response

Question 3

outline the fight or flight responce

Answer 3

In response to acute stress, the body’s sympathetic nervous system is activated due to the sudden release of hormones

Signalling function (we might take action)
Provide strong impulse to take action
Promote unique, stereotypical patterns of physiological change and behaviour

Question 4

what are positive or negative emotions

Answer 4

Negative Emotions: moving away from what one doesn’t want

Positive Emotions: moving towards what one does want

Question 5

outline folk psycholgoy belief

Answer 5

First comes conscious awareness, then comes physiological responses

Question 6

Outline James Lange theory

Answer 6

William James and Carl Lange proposed an idea that was diametrically opposed to the common-sense view Physiology –> Appraisal
Stimulus (dog)
–> perceptioninterpretation of danger –> (dog)
Perception/ Interpretation (danger)
Specific pattern of automatic arousal (heart races)
–> particular emotion expressed

Question 7

what is Cannon-Bards theory

Answer 7

Walter Cannon and Phillip Bard proposed that an emotion-triggering stimulus elicits the recognition of emotion and then body’s arousal takes place
Appraisal –> Physiology
Stimulus (dog)
Perception/ Interpretation (danger)
Emotion Experience
Specific pattern of automatic arousal (heart races)

Question 8

evaluate the cannon-bard theory and the James- Lange theory

Answer 8

J-L: Assumes there is a unique physiological signature to each emotion

C-B: Physiological responses are generated so quickly, it’s unlikely that we could have perceived the emotion first

Question 9

Outline the Schachter-Singers theory

Answer 9

To experience emotion one must:

(1) be physically aroused
(2) cognitively label the arousal

stimulus –> specific patterns of automatic arousal AND cogntive label e.g. “I am afraid” –> particular emotion expressed

Question 10

explain Schachter-Singers classic experiment

Answer 10

In a 1962 experiment:
A group of 184 male participants was injected withepinephrine (hormone that produces arousal including increased heartbeat, trembling, and rapid breathing)
“a new drug to test theireyesight”
• Group A = informed the side-effects that the injection might cause • Group B = ignored side-effects
Placed in room with happy or angry confederate Participants with no explanation for arousal experienced happiness or anger

Question 11

Must cognition precede emotion?

Answer 11

Some emotional reactions may occur without conscious thinking
Emotions involve bodily responses
Bodily responses are very noticeable (butterflies in our stomach when fear arises)
but others are more difficult to discern (neurons activated in the brain)

triangle forms between behavor, cognition, emotion arrows go both ways

Question 12

what are the two dimensions of emotions

Answer 12

positve/negative valence
low arousal vs high arrousal

e..g positve valence but low arounsal = relaexed
low arousal and neg valence = sadness
high arousal and pos valence = joy
high arousal neg valence = fear or anger

Question 13

what is the ANS

Answer 13

Autonomic Nervous System (ANS) controls our arousal

part of the nervous system responsible for control of the bodily functions not consciously directed: breathing, heartbeat, and digestive processes

uses epinephrine

Question 14

what are the similarities and differences in emotions?

Answer 14

Physiological responses related to the emotions of fear, anger, love are very similar
Excitement and fear involve a similar physiological arousal

Brain responses related to the emotions are slightly different
“Different” brain areas activated by different emotions

Question 15

what is a polygraph?

Answer 15

A lie detector
machine used in attempts to detect lies Physiological Responses: -perspiration -cardiovascular changes -breathing changes

BUT:
Control-Question Technique ANS responses to answers to innocuous questions (Is your mother’s name Betty?) are compared to those of target questions (Did you steal the money?)
50 Innocents 50 Thieves 2/3 of innocent declared guilty 1/4 of guilty declared innocent

Question 16

how are emotions expressed?

Answer 16

Emotions are expressed on the face, by the body, and by the intonation of voice
Ekman and Friesen analyzed hundreds of films and photos of people experiencing various emotions
They concluded that there are 6 primary facial expressions of emotionsand all others are mixtures of these
Anger, fear, disgust, surprise, happiness,sadness

Question 17

outline culture impacts of emotional facial expressions

Answer 17

Facial expressions are universal
different cultures linked the same emotions to the facial expressions
isolated New Guinea tribe members could correctly identify facial expressions

Question 18

outline the brain circuits of emotion

Answer 18

particular brain regions are involved in emotion, but often the same areas seem to be involved in many different emotions electrical stimulation of the septum (in rodents)

Question 19

how do brain lesions effect emotions

Answer 19

decorticate cats/dogs (without cortex) respond with unusual aggression to the slightest provocation sham rage ( à it lacks well-directed attack )
Emotional behaviors must be organized at SUBCORTICAL, with the cerebral cortex normally providing inhibitionof emotional responsiveness

Question 20

what is the papez circuit

Answer 20

is a neural circuit for the control of emotional expression. In 1937, James Papez proposed that the circuit connecting the hypothalamus to the limbic lobe was the basis for emotional experiences.

Subcortical Circuit of Emotion “destruction of a set of interconnected pathways in the brain would impair emotional processing”

Emotional system on the medial wallof the brain linking cortexwith hypothalamus

Question 21

what is the limbic system

Answer 21

Neocortex cingulate cortex (emotional experience) -> hippocampus -(fornix-> hypothalamus (emotional expression) –> anterior nuclei of thalamus –> cingulate cortex

Question 22

outline experimental evidence ofthe limbic system

Answer 22

Temporal Lobe lesion in primates Kluver-Bucy Syndrome
No fear or aggression after surgery
Lesions restricted to the cerebral cortex do not produce these results à deeper regions of the temporal lobe (including sites within the limbic system) are implicated

Question 23

what is the amyglada

Answer 23

amygdala appears to be involved in the perception of fear (as opposed to the expression of emotions)
female patient first described in 1994, who has had a complete bilateral amygdala destruction since late childhood.
She has little to no capacity to experience fear in her life “woman with no fear”

but when patients with amyglada lesion inhaed 35% CO2 triggered fear reposnces and panic attacks- more important in control of expternal fear rather than internal stimuli

Question 24

outline lateralization of emotions

Answer 24

left hemisphere: less involved in the perception of emotion
LH lession: depressive symptoms

RH is more involved in perception of emotion, specifically facial expression and prosody
(melody of speech that conveys sincerity, sarcasm, etc.)
Presentation of emotional stimuli on the LEFT visual field à faster reaction times and accurate identification

RH lesion: Euphoria lesions

Question 25

what areas are invovled in processing emotion?

Answer 25

several forebrain areas involved in Emotional Processing
ruly, deeply, and madly in love” Love compared with friendship involved increased activity in the insulaand anterior cingulate cortex (ACC) and subcortically in the caudate and putamen (bilaterally)