The Neurobiology of Love Flashcards
What is the take-home message of Harlow’s study of social attachment?
A child’s love for their caregiver was emotional rather than physiological
What were four consequences of social isolation for the first 3-12 months of life in monkeys?
- Abnormal social behaviour
- Timid and autistic rocking
- Abnormal sexual behaviour
- Abnormal parenting behaviour
In all cases it was difficult or impossible to compensate for the loss of initial emotional security
Give the ultimate and proximal reasons for parental behaviour
Ultimate: Passing on genes
Proximal: Protection, nutrition, temperature regulation, shelter and learning (instincts)
What is alloparenting?
Parenting given by individuals that are not the biological mother or father
List the three different types of maternal care in mammals with a placental (eutherieans)
Altricial: Helpless offspring (eg. dogs, rabbits)
Precocial: Little help required for survival (eg. hoofed mammals, ungulates)
Semi-prococial/semi-altricial: humans and other primates
What is the maternal experience effect?
How is this blocked (two ways)
Brief interaction (at least 30 minutes) with pups after birth sustains maternal responsiveness throughout lactation and beyond
Seeing, smelling and/or hearing pups not enough
Cyclohexemide (protein synthesis inhibitors) injections soon after maternal experience prevents consolidation and blocks the maternal experience effect
Lesions of the nucleus accumbens also prevents consolidation
Access to pups is rewarding to mothers in skinner box. How is this effect blocked?
Dopamine antagonist
What happens when you transfer blood from a maternal rat to a virgin rat?
Virgin rat will show maternal behaviour
Which voles are love voles?
Prairie vole: love vole (monogamous, biparental)
Montane/meadow vole: party vole (promiscuous, maternal)
How do prairie (love) voles differ from montane (party) voles with OXT and VP receptor distributions
OXTR: Decrease in party vole
VPR: Decrease in party vole
This makes sense as oxytocin surges in females and vasopressin surges in males after mating, both associated with pair bond formation (necessary).
After cohabitation in males, vasopressin immunoreactivity decreased in lateral septum and increaed in BNST
Lesions of what area will abolish maternal behaviour?
What area of the brain inhibits this maternal are?
MPOA in hypothalamus
The amygdala inhibits the activity/behaviour produced by the MPOA through the BNST
How does oxytocin receptor activation overcome the amygdala’s inhibitory restraint on maternal behaviour?
Describe the effect of maternal tactile stimulation on this
Stat5 upregulates ER-alpha to up-regulate the oxytocin receptor
Estrogen-receptor complex binds to ERE promoter on oxytocin receptor gene
Maternal tactile stimulation causes hypomethylation of the ER-alpha
This methylation patter, particularly in Stat5 response elements, may explain differences in ER-alpha expression between high and low stimulates females
Describe epigenetics and vole love
Histone deacetylase inhibitor facilitates partner preference formation in female prairie voles
Histone deacetylation (chromatom condensation) is inhibited following pair formation.
Leads to upregulation of OTR and vasopressin receptor in NAcc through increase in histone acetylation at their respective promoters
Describe where activation is observed in human brains when viewing pictures of romantic (loved) partners.
Indicate the areas which have VP and OX receptors.
- Medial insula
- Anterior cingulate cortex
VP/OX receptors
- Caudate putamen
- Globus pallidas
- Hippocampus
- Hypothalamus
- VTA
