L16 Emotion And Motivation

Question 1

What is behaviour influenced by?

Answer 1

Internal states

Question 2

What are the 4 Fs of internal state?

Answer 2

1. Feeding
2. Fighting
3. Fleeting
4. Mating

Question 3

What does Perturbation mean?

Answer 3

It refers to a small change or deviation in the regular motion or state of a system, often caused by an external influence.

Question 4

What is leptin?

Answer 4

Leptin is a hormone produced by adipose tissue (body fat) that reduces fat.

Question 5

How does Leptin reduce body fat?

Answer 5

Leptin increases metabolic rate to which it decreases body fat and it also reduced appetite

Less leptin = less body fat

Question 6

Which part of the brain is responsible for anorexigenic (loss of appetite) and orexigenic (appetite stimulating)?

Answer 6

Lateral hypothalamus - hunger (orexigenic)

Ventromedial nucleus - satiety (anorexigenic)

Question 7

What two hormones does the lateral hypothalamus secrete in regulating appetite and feeding behaviour?

Answer 7

Orexin and MCH

Question 8

What hormones are expressed in the Arcuate nucleus (within the hypothalamus)?

Answer 8

• POMC/αMSH/
  CART inhibits the lateral hypothalamus
• NPY/AgRP stimulates the lateral hypothalamus

Lateral hypothalamus stimulates hunger (more eating)

Question 9

How does Leptin affect eating behaviours?

Answer 9

Leptin:
- stimulates POMC/αMSH/CART
- Inhibits NPY/AgRP

Question 10

What effects does the POMC/αMSH/
CART and NPY/AgRP have on the paraventricular nucleus?

Answer 10

POMC/αMSH/
CART stimulates paraventricular nucleus but NPY/AgRP inhibits it

Opposing effects for lateral hypothalamus

Question 11

Does the paraventricular nucleus inhibit or stimulate hunger?

Answer 11

It inhibits hunger (gives you the feeling of being full)

Only lateral hypyothalamus promotes an appetite

Question 12

How does the hormones within the Arcuate nucleus affect the ANS?

Answer 12

• POMC/αMSH/
  CART stimulates the SNS (stimulates metabolic rate)
• NPY/ AgPR stimulates PNS (inhibits metabolic rate)

Question 13

How does the pituitary gland increase metabolic rate?

Answer 13

The paraventricular nucleus (in hypothalamus) activates the pituitary gland to which it secretes TSH/ACTH which stimulates metabolic rate

Question 14

How does blood glucose promote/inhibit eating?

Answer 14

Blood glucose can inhibit the lateral hypothalamus and stimulate ventromedial nucleus

Question 15

How does drug GLP-1 help people lose weight by reducing appetite?

Answer 15

GLP-1 promotes insulin secretion which secretes POMC/αMSH/CART which inhibits the lateral hypothalamus which can reduce hunger

Question 16

How does the digestive system affect eating behaviours?

Answer 16

When stomach is full - blood glucose increases, body fat increases and leptin is produced or it can inhibit Ghrelin

Question 17

What is Ghrelin?

Answer 17

Ghrelin stimulates hunger

Question 18

What does Ghrelin do within the hypothalamus?

Answer 18

Ghrelin stimulates NPY/AgRP production which can promote lateral hypothalamus and inhibit paraventricular nucleus which inhibits eating (acts as a double negative)

Question 19

Why do we have an odd number of inhibitory arrows in the loop?

Answer 19

There is an odd number of inhibitory arrows in the feedback loops because realistically we can’t keep eating therefore there must be one more inhibitory route that allows us to stop eating when we are full

Question 20

When is CCK produced and what are the effects?

Answer 20

When stomach full = nutrients in intestines = CCK released = activates receptors on solitary nucleus (brainstem) which inhibits eating

Question 21

Is the signalling produced by neuroleptics and hormones slow or fast?

Answer 21

They are slow

Question 22

What is the difference between unconditioned stimulus and a conditioned stimulus?

Answer 22

Unconditioned stimulus (UCS) is a stimulus that naturally and automatically triggers a response without any learning

Condition stimulus - Previously a neutral stimulus which comes to a learnt stimulus for example bell ringing before food is presented makes dog salivate.

Question 23

Which brain areas are involved in aggression?

Answer 23

Cerebral cortex, amygdala and hypothalamus

Question 24

What happens if you stimulate the medial/ lateral part of the hypothalamus?

Answer 24

• Medial hypothalamus - affective aggression
• Lateral hypothalamus - predatory aggression

Question 25

What is the difference between affective and predatory aggression?

Answer 25

- Affective - driven by strong emotions such as anger, fear, or frustration - Predatory - driven by desire to obtain a goal, such as food or resources

Question 26

What does VMHvl stand for?

Answer 26

Ventromedial hypothalamus, ventral lateral subdivision

Question 27

What are the evidences that suggest hypothalamus’ role can be aggression?

Answer 27

- Electrical stimulation of specific areas of the hypothalamus causes affective/predatory aggression - Listening to the sound of neurons firing in the VMHvl when intruder is present compared to no intruders - Optogenetics ( on and off lights)

Question 28

When is dopamine secreted?

Answer 28

It's released when we experience something pleasurable or anticipate a reward.

Question 29

What happens if you destroy the mesolimbic dopaminergic projections?

Answer 29

Lack motivation to seek food but still enjoy the food meaning dopamine has to give you motivation in doing something rather than the pleasure of doing something ## Footnote So it doesn't want (unmotivated) but it likes the food

Question 30

What is the Orbitofrontal cortex (OFC) responsible for?

Answer 30

The OFC is heavily involved in evaluating the value of rewards and punishments. It helps us learn associations between stimuli and their outcomes, allowing us to make informed decisions ## Footnote Damage to the OFC includes increased risk-taking