Chapter 12 part 1

Question 1

What causes emotional and motivated behaviour?

Answer 1

Brain has need for stimulation
Evolution - innate releasing mechanisms
Environmental influencers - reinforcers and preparedness
Neural circuits for motivated behaviour (olfaction and gustation)

Question 2

What do sensory derivation experiments show?

Answer 2

Brain has a need for stimulation - will only last 4-8 hours and begin hallucinating

Question 3

What are innate releasing mechnanisms?

Answer 3

Hypothetical prewired neural system that detects certain stimuli and triggers and adaptive response - brain has built in norms for recognizing and responding to cues without past experience

Question 4

Give an example of an innate releasing mechanism in animals?

Answer 4

6 week old kittens respond (act defensively) to halloween cat but not to scrambelled cat

Question 5

Give an example of an innate releasing mechanism in humans?

Answer 5

Newborns are too young to be imitating adult faces - babies innately match these facial expressions to internal templates
Blind babies even do this

Question 6

Can innate releasing mechanisms be modified with experience?

Answer 6

Yes

Question 7

What is operant conditioning?

Answer 7

Behaviour is shaped by reinforcers

Question 8

What is preparedness? Give 3 examples?

Answer 8

We are predisposed to learn certain associations faster than others
Rats who experience unavoidable shock immediately start fighting
Pigeons associate pecking with food not with electric shock avoidance
Learned taste aversions

Question 9

What are the neural circuits that modulate rewards?

Answer 9

Hormones
Chemical senses (smell and taste) - stimulate different behaviours

Question 10

How do we tell the difference between different odors given that we only have 400 olfactory receptors?

Answer 10

A given odorant stimulates a unique pattern of receptors

Question 11

What do the odorants bind to in the olfactory system?

Answer 11

first the Mucosa and then interacts with chemical receptors on olfactory epithelium.

Question 12

What type of receptors are used in the olfactory system?

Answer 12

Metabotropic G protein coupled receptor (Golf protein)

Question 13

Describe the steps in the olfactory pathway?

Answer 13

Olfactory receptor cells –> olfactory bulb –> glomeruli –> mitral cells –> Pyriform cortex or other areas

Question 14

What is the primary olfactory cortex called? What about the secondary?

Answer 14

Pyriform cortex; OFC (orbital frontal cortex)

Question 15

What are the other areas in the forebrain that the information from mitral cells can go to?

Answer 15

amygdala (emotion), entorhinal cortex (memory), hypothalamus

Question 16

Do olfactory pathways go directly through thalamus?

Answer 16

No

Question 17

Describe the pathway from the pyriform cortex to the secondary olfactory cortex?

Answer 17

pyriform cortex –> medical dorsal thalamus –> OFC

Question 18

What does the OFC do?

Answer 18

associates taste/ odor with reward

Question 19

What types of smells are humans sensitive to?

Answer 19

Ones that are behaviourally relevant – can identify odor of kin, their own odor or odor of friends vs strangers

Question 20

What do body odors activate?

Answer 20

brain regions involved in emotional processes

Question 21

What happened in the study when people were presented with abdrostadienone (human sweat hormone)?

Answer 21

Strangers odor activates the amygdala and the insular cortex

Positive stimuli and sweat hormone –> decreases amygdala activation and increases PFC and OFC activation (associates odor with reward)

Question 22

How much many taste receptors have humans lost by age 20?

Answer 22

50%

Question 23

What is the taste sense?

Answer 23

gustation/ gustatory

Question 24

What is the difference between mildtasters, supertasters, nontasters?

Answer 24

taste receptor gene codes for bitterness
Super tasters have more taste bubs and papillae

Question 25

Which cranial nerves form the main gustatory nerve?

Answer 25

7, 9, and 10

Question 26

What is the main gustatory nerve called?

Answer 26

The solitary tract

Question 27

Where does the solitary tract split to form two tracks?

Answer 27

at the brainstem

Question 28

Describe the 1st gustatory pathway?

Answer 28

Nucleus of solitary tract --> thalamus --> primary somatosensory cortex and primary gustatory cortex

Question 29

What does the primary somatosensory cortex do for gustation?

Answer 29

tactile stimulation

Question 30

What is the name of the part of the primary gustatory cortex that projects to the OFC?

Answer 30

Anterior insular

Question 31

What does the anterior insular do?

Answer 31

dedicated to taste

Question 32

What give rise to perception of flavour?

Answer 32

mixture of olfactory and gustatory input

Question 33

What do the areas in the right and left OFC do for taste?

Answer 33

right OFC mediates pleasantness of taste left OFC mediates unpleasantness of taste

Question 34

What do the amygdala and hypothalamus do for gustation?

Answer 34

pleasantness and strength of flavours -- not association between food and emotion (that isnthe OFC

Question 35

What is the second pathway of the gustatory system?

Answer 35

Nucleus of solitary tract --> hypothalamus and amygdala

Question 36

What is loss of gustatory function?

Answer 36

Ageusia

Question 37

What is ageusia?

Answer 37

Decreased hygiene, increased depression , failure to activate digust