Lecture 16 Flashcards
(27 cards)
mesolimbic pathway
- infusions into the nucleus accumbens
- DA antagonists = impaired pup retrieval
- D1 agonist = enhanced maternal behavior
POA
antagonists = impair maternal behavior
- prior maternal experience leads to elevated extracellular DA concentrations
maternal aggression
- 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
progesterone and maternal aggression
- 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
cortico-releasing hormone (CRH)
- infusions (ICV) of CRH inhibit maternal aggression but do not affect other maternal behaviors
- decreased CRH is important for maternal aggression
maternal behavior in rhesus monkeys
- 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
what do pregnancy hormones do
- may influence motivation to show parental behavior
- might facilitate interest or motivation
self-report of self-image and maternal engrossment in humans
no correlation between maternal attitudes and hormone concentrations
high cortisol in mothers associated with
- greater attraction to their infants’ odors
- better at identifying their infants’ odors
- gave the odors a higher hedonic rating
only in first time mothers
oxytocin
- higher concentrations = greater affectionate contact and eye gaze with 4-5 month olds
- greater increases across pregnancy = greater maternal bonding postpartum
mothers genotyped with presumably high oxytocin receptor expression had
- higher positive parenting scores
- greater neural responses to images of their children
prolactin in California mice fathers
higher prolactin levels = higher levels of paternal care
testosterone in California mice fathers
males behaving paternally show reduced testosterone concentrations compared to non paternal males
new fathers + testosterone and cortisol
expectant fathers showed reduced plasma testosterone and cortisol levels compared with control subjects
exposure to infant cries
- fathers felt more sympathetic and alert
- fathers and nonfathers with lower salivary testosterone concentrations felt more sympathy and need to respond compared to fathers with high testosterone concentrations
- father with higher blood prolactin levels were more alert and more responsive to the cries
oxytocin and parental care
- 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
in parent-child interactions
father with polymorphisms in the gene encoding OT receptor show increased parental interactions
neural changes associated with parental behavior: MPOA
- 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
parenting activates ____ neurons in the MPOA
Galanin-expressing
ablation of ___ MPOA cells impairs parental behavior in virgin females (and nursing mothers)
Gal
Gal MPOA cells
critical for maternal behavior exhibited in virgin females
ablation of ___ MPOA cells also impairs parental behavior in fathers
Gal
stimulating Gal MPOA neurons in virgin males
reduced attacks and induced pup grooming
nonpregnant adult females and adult males exposed to pups will either
retreat/avoid or attack (chemosensory based revulsion)
