Ch 7

Question 1

Average adult human circadian rhythm of cortisol

Answer 1

Cortisol elevates overnight, highest at point of waking, decreases throughout the day and lowest in the evening.

Question 2

Moderate levels of cortisol can…

Answer 2

lead to feelings of happiness because it decreases the breakdown of monoamine NTs.

Question 3

Thermoregulation and the HT and pituitary

Answer 3

Heat conservation -> posterior nucleus of HT -> pituitary… rise in thyroid hormone secretion, shivering, piloerection, vasoconstriction. SNS activation.
Heat dissipation -> preoptic area (POA of HT) -> pituitary… decrease in thyroid hormone secretion, panting, thirst, sweating, vasodilation, decreased SNS activation.

Question 4

Pain fibers

Answer 4

C fibers: no myelin, slow, dull, aching pain.
A delta fibers: myelin, fast, sharp, pricking pain.
All pain fibers synapse in the dorsal horn of the spinal cord.

Question 5

Pain Pathways to the Brain

Answer 5

Spinothalamic -> Thalamus (synapses in the medial and lateral thalamus and continues to the cortex).
Spinoreticular -> Reticular formation (synapses in the medial thalamus and continues to the cortex).
Spinomesencephalic -> midbrain (synapses in the reticular formation and PAG. PAG signals to HT).

Question 6

Endorphins and Enkephalins

Answer 6

Endorphins are released from the pituitary during stress. (HT- CRH and pituitary- ACTH).
Enkephalins are small peptides from diverse sources. They are concentrated in the PAG and dorsal horn of the spinal cord.

Question 7

Analgesia

Answer 7

A loss of pain sensation. Endorphin receptors in PAG and dorsal horn of spinal cord interact with endorphins, enkephalins and opioids to produce analgesia.
Descending tracts from brain to spinal cord. Can inhibit pain messages at spinal synapses with inhibitory interneurons. We rub ourselves when we’re hurt so that touch receptors drown out pain receptors.

Question 8

Adaptations level hypothesis

Answer 8

subjective intensity of pain perception relative to past experiences.

Question 9

Pain and emotions

Answer 9

Pain causes anger, frustration, social withdrawal. Negatively impacts mental health, family relationships, work, social behavior.

Question 10

Nature of Fear

Answer 10

Pain is a response to actual damage. Fear is a response to the anticipation of damage.

Question 11

Conditioning of Fear

Answer 11

Single traumatic events associated with rapid- one trial fear conditioning.
Social transmission of fear observed in parent-child relationships.

Question 12

Fear responses are mostly…

Answer 12

Innate. Learning new responses to fearful stimuli is difficult. Fear remains because of unlikely exposure to feared stimulus.

Question 13

List some species-specific defense reactions

Answer 13

fighting, fleeing, freezing, hiding burrowing, perspiration, screaming, urination, defecation.

Question 14

Fear Physiology in CNS and SNS

Answer 14

CNS:
- Stimulation of dorsal HT induces flight behaviour.
- Stimulation of PAG turns calm animal into defensive animal.
SNS:
- constriction of blood vessels supplying skin, digestive tract
- dilation of blood vessels supplying skeletal muscles
(Alpha receptors -> constrict, Beta receptors -> dilate)

Question 15

What are the adrenal and central catecholamines?

Answer 15

Adrenal: epinephrine and norepinephrine
Central: dopamine and norepinephrine

Question 16

Amygdala

Answer 16

Affects how we perceive things as good/bad, critical for balance of approach and avoid behaviours.
Electrical stimulation of lateral areas can induce fear, and stimulation of other areas can diminish fear.

Question 17

Amygdala Nuclei

Answer 17

Basolateral nucleus: integrates sensory stimuli and memories during fear conditioning
Cortical nucleus: involves sense of smell and pheromone processing
Centromedial nucleus: involves emotional arousal

Question 18

Amygdala Connections

Answer 18

HT (activates SNS), thalamic reticular nucleus (involves reflexes), trigeminal and facial nuclei (emotional and facial processing), ventral tegmental area and locus coeruleus (dopamine and norepinephrine)

Question 19

Gradual atrophy of the amygdala, no special memory for traumatic events, no fear recognition in others, reduced fearfulness…

Answer 19

Urbach-Wiethe Disease

Question 20

Pheromones and Fear

Answer 20

Studies show that cattle and mice will avoid areas where conspecifics have previously been frightened. Suggests a chemical transmission of fear.

Question 21

Outline the mechanism of concurrent blood vessel dilation and constriction during SNS activation?

Answer 21

Tissues and organs in the body possess two different adrenergic receptors, which respond differently to both adrenaline and noradrenaline.

Question 22

Blocking ___ induces anxiety and injecting ___ induces panic

Answer 22

GABA; CCK

Question 23

Key Point of Chapter 7 Reading on Swearing

Answer 23

For people who do not regularly swear very much, swearing provides effective pain reduction. For people who regularly swear often, this does not have the same effect.