Lecture 16

Question 1

mesolimbic pathway

Answer 1

• infusions into the nucleus accumbens
• DA antagonists = impaired pup retrieval
• D1 agonist = enhanced maternal behavior

Question 2

POA

Answer 2

antagonists = impair maternal behavior
- prior maternal experience leads to elevated extracellular DA concentrations

Question 3

maternal aggression

Answer 3

• protection from predators or infanticidal conspecifics
• beginning mid-pregnancy through 1 week postpartum, mouse dams act aggressively towards male intruder
• threat behaviors and biting
• progesterone

Question 4

progesterone and maternal aggression

Answer 4

• nulliparous given P = increased aggression
• pregnant females the peak of P = onset of aggression
• pregnancy termination on day 15 eliminates aggression
• postpartum ovariectomy reduces maternal aggression

Question 5

cortico-releasing hormone (CRH)

Answer 5

• infusions (ICV) of CRH inhibit maternal aggression but do not affect other maternal behaviors
• decreased CRH is important for maternal aggression

Question 6

maternal behavior in rhesus monkeys

Answer 6

• nulliparous monkeys avoided the infant, fear response
• multiparous monkeys immediately accepted the infant, higher circulating levels of estradiol and progesterone
• hormonal status does not matter
• experience DOES matter

Question 7

what do pregnancy hormones do

Answer 7

• may influence motivation to show parental behavior
• might facilitate interest or motivation

Question 8

self-report of self-image and maternal engrossment in humans

Answer 8

no correlation between maternal attitudes and hormone concentrations

Question 9

high cortisol in mothers associated with

Answer 9

• greater attraction to their infants’ odors
• better at identifying their infants’ odors
• gave the odors a higher hedonic rating
  only in first time mothers

Question 10

oxytocin

Answer 10

• higher concentrations = greater affectionate contact and eye gaze with 4-5 month olds
• greater increases across pregnancy = greater maternal bonding postpartum

Question 11

mothers genotyped with presumably high oxytocin receptor expression had

Answer 11

• higher positive parenting scores
• greater neural responses to images of their children

Question 12

prolactin in California mice fathers

Answer 12

higher prolactin levels = higher levels of paternal care

Question 13

testosterone in California mice fathers

Answer 13

males behaving paternally show reduced testosterone concentrations compared to non paternal males

Question 14

new fathers + testosterone and cortisol

Answer 14

expectant fathers showed reduced plasma testosterone and cortisol levels compared with control subjects

Question 15

exposure to infant cries

Answer 15

1. fathers felt more sympathetic and alert
2. fathers and nonfathers with lower salivary testosterone concentrations felt more sympathy and need to respond compared to fathers with high testosterone concentrations
3. father with higher blood prolactin levels were more alert and more responsive to the cries

Question 16

oxytocin and parental care

Answer 16

• concentrations increase in the first 6 months of parenthood
• fathers with toddlers = higher concentrations
• intranasal OT delivery in father leads to increased social gaze, touch, and positive affect

Question 17

in parent-child interactions

Answer 17

father with polymorphisms in the gene encoding OT receptor show increased parental interactions

Question 18

neural changes associated with parental behavior: MPOA

Answer 18

• excitotoxic lesions severely disrupt maternal behavior 4 days postpartum
• estrogen implants stimulate parental behavior
• role changes across the postpartum period
• early –> stimulates PB
• late –> inhibits PB
• may regulate onset, maintenance, and termination

Question 19

parenting activates ____ neurons in the MPOA

Answer 19

Galanin-expressing

Question 20

ablation of ___ MPOA cells impairs parental behavior in virgin females (and nursing mothers)

Answer 20

Gal

Question 21

Gal MPOA cells

Answer 21

critical for maternal behavior exhibited in virgin females

Question 22

ablation of ___ MPOA cells also impairs parental behavior in fathers

Answer 22

Gal

Question 23

stimulating Gal MPOA neurons in virgin males

Answer 23

reduced attacks and induced pup grooming

Question 24

nonpregnant adult females and adult males exposed to pups will either

Answer 24

retreat/avoid or attack (chemosensory based revulsion)

Question 25

VNO-MPOA pathway

Answer 25

1. vomeronasal organ
2. accessory olfactory bulbs
3. lateral olfactory tract
4. medial nuclei of the amygdala
5. stria terminalis
6. bed nucleus of the stria terminalis
7. medial pre optic area