Lecture 9 - Emotion

Question 1

What are emotions?

Answer 1

• survival mechanisms
• the brain area primarily involved in emotion is the limbic system

Question 2

What areas are involved in emotional responses?

Answer 2

• Emotional stimuli are relayed by our sensory systems to the amygdala
• The perception of emotion is created both by direct and indirect signals from the amygdala to the frontal cortex
• The indirect path involves the hypothalamus, which sends messages to the autonomic nervous system creating physical changes in body state (e.g. increased heart rate)
• These changes are then fed back to the frontal cortex which interprets the emotion

Question 3

Amygdala and emotional behaviour?

Answer 3

• has a bilateral structure and is part of the limbic system & within the temporal lobes

Question 4

What is Klüver-Bucy Syndrome?

Answer 4

• results from damage to the medial temporal lobe
• monkeys with KB syndrome =
  -> loss of normal anger and fear responses

Question 5

The amygdala and emotional memory in rats?

Answer 5

• plays an important role in improving the chances of survival
• minimises contact with dangerous animals, objects and places

Question 6

The amygdala and emotional memory in humans?

Answer 6

• the amygdala is responsible for generating negative emotions
• involved in acquiring fear through observation
• is responsible for emotional memories in humans
  -> increased activity when recalling emotional videos vs neutral ones
  -> increased activity when seeing threat-related words vs neutral

Question 7

Patient SM?

Answer 7

• had bilateral damage to the amygdala
• was impaired in rating the intensity of a variety of emotions specifically fear and anger
• unable to sketch a face depicting fear

Question 8

What is the James Lange theory?

Answer 8

the idea that emotions result from changes in body state

Question 9

Changes in body state associated with emotion?

Answer 9

• Hypothalamus releases corticotropin-releasing hormone (CRH)
• CRH then acts on the anterior pituitary gland to release adrenocorticotropin hormone (ACTH)
• ACTH act on adrenal glands to release cortisol into the blood stream
• Makes up our stress response
• This signalling system then affects the activity of the autonomic (internal) nervous system (ANS)
• The ANS has motor and sensory neurons, the sensory neurons report physiological changes in the body caused by the motor neurons

Question 10

Hypothalamus?

Answer 10

• The hypothalamus contains neurons that control a variety of body functions such as: body temperature, heart rate, blood flow, eating and drinking, these neurons receive connections from the amygdala
• The importance of the hypothalamus in emotional responses was found by studying animals with lesions to the cerebral cortex but an intact hypothalamus
• These animals were very aggressive to any external stimulus
• This study also shows the importance of an intact cerebral cortex to interpret emotional states

Question 11

The prefrontal cortex and emotional behaviour?

Answer 11

• Egas Moniz carried out a procedure known as a frontal lobotomy = changes a persons personality, removing the capacity to understand their emotions
• intuitively this should produce a more rational person
• however it would appear that emotional responses are a necessary function of rational decision making

Question 12

How is emotionality lateralised in the cerebral hemispheres (2 ways)?

Answer 12

1. the right hemisphere is important in the expression and comprehension of emotional aspects of speech
2. the left hemisphere is associated with positive emotions whereas the right hemisphere is associated with negative ones

Question 13

How do we express our emotions?

Answer 13

• through movements of the face
• different facial expressions show happiness, anger etc.
• Darwin proposed that emotional expression is inherited as these responses are similar in different cultures