Lecture 8 (copy)

what is the value of peers in social species?

Isolation is stressful (loneliness and social exclusion), social contact is rewarding, and social contact buffers against stress and illness.

what is known about how the brain is involved in peer relationships?

Surprisingly little is known about how the brain is involved.

what is a pair bond?

A social relationship between two individuals characterized by preference for each other and behaviors such as huddling.

what is a peer bond?

A social affiliation between individuals (often same-sex) without mating that is measured through behaviors such as time spent together or huddling.

what method is used to measure pair bonding in animal studies?

Time spent with a partner versus another animal, typically measured using partner preference or huddling behavior.

what method is used to measure peer bonding in animal studies?

Time spent huddling or affiliating with a familiar peer compared with unfamiliar individuals.

what species differences are important when studying vole bonding?

Prairie voles and pine voles are monogamous, whereas montane voles and meadow voles are polygamous.

what does socially monogamous mean in prairie and pine voles?

They may have multiple sexual partners but show a strong preference for one partner.

what vole species are monogamous?

Prairie voles and pine voles.

what vole species are polygamous?

Montane voles and meadow voles.

what experimental design is used to study bonding without mating?

Same-sex animals are used to examine peer bonding instead of mating behavior.

what behavior is measured when testing peer bonding in voles?

Time spent huddling with a partner or peer.

what behavior is seen in mice in huddling experiments?

Mice do not huddle much and show very little time spent together.

what bonding behavior is seen in prairie voles?

Prairie voles show a strong preference for partner huddling and form same-sex peer bonds.

what seasonal behavior is seen in meadow voles?

Meadow voles can form pair bonds during the non-breeding season.

what is the purpose of meadow vole bonding during the non-breeding season?

It helps them survive the winter.

what survival behavior occurs among rodents in winter?

Meadow voles may huddle with other rodents to conserve heat and survive.

what ecological factor reduces competition during the non-breeding season?

Survival becomes the priority, so competition for mates or territory decreases.

what behavior occurs during the breeding season in meadow voles?

They become very territorial and do not form pair bonds.

what experimental question was tested in meadow voles?

The effect of season and hormones on how female meadow voles bond with others.

what environmental condition represents breeding season in experiments?

Long-day light cycles.

what hormonal change occurs in long-day breeding conditions?

Increased estradiol.

what effect does estradiol have on peer bonding in meadow voles?

Increased estradiol decreases peer bonding.

what experimental manipulation tested estradiol’s role in bonding?

Estradiol was added back to test its effect on bonding.

what hormones are commonly associated with social bonding?

Oxytocin (OT) and vasopressin (AVP).

what role do oxytocin and vasopressin play in bonding?

Their levels increase with bonding and social contact.

what additional role might oxytocin and vasopressin signal?

They may signal a need to increase social affiliation.

what study investigated the role of oxytocin and vasopressin in bonding?

Taylor et al.

what was discovered about oxytocin knockout prairie voles?

They are not aggressive and can still form bonds.

what does oxytocin knockout research suggest about bonding?

Oxytocin is not strictly necessary to form a bond.

what result was observed in Panel D of the prairie vole experiment?

Oxytocin knockout females did not form bonds within 24 hours.

what longer-term bonding result was observed in oxytocin knockout females?

They eventually formed bonds, but it took longer.

what result was observed in Panel E of the prairie vole experiment?

Oxytocin knockout females could form a peer bond with a new female.

what does prairie vole research suggest about bonding mechanisms?

The brain processes partner bonds differently from peer bonds.

what experiment compared neural processing of partner versus peer bonds?

Comparison of neural activation patterns between partner bonding and peer bonding conditions.

what neurotransmitter system was tested in bonding experiments?

Dopamine.

what dopamine antagonist was used in bonding experiments?

Haloperidol.

what dopamine agonist was used in bonding experiments?

Apomorphine.

what effect did dopamine antagonists have on peer bonding?

Dopamine antagonists did not block peer bonding.

what effect did dopamine agonists have on peer bonding?

Apomorphine facilitated the formation of peer bonds.

what conclusion can be drawn about dopamine in bonding?

Dopamine facilitates social bonding.

what brain regions increase activity during social exclusion?

The anterior cingulate cortex (ACC) and rostral ventral prefrontal cortex (rvPFC).

what does increased ACC activation during exclusion indicate?

Greater distress from social exclusion.

what does increased prefrontal cortex activation during exclusion indicate?

Reduced feelings of social distress.

what neural relationship exists between the ACC and PFC?

The PFC dampens ACC activity.

what is the ACC associated with in pain and social experiences?

Emotional distress and pain.

what role does the PFC play in coping with distress?

It dampens ACC activity to help regulate distress.

what experiment tested social buffering with oxytocin and social support?

Participants received oxytocin nasal spray or placebo and either had social support or no support while cortisol was measured.

what physiological stress measure was used in the social buffering experiment?

Cortisol levels measured in saliva.

what condition produced the highest cortisol levels?

No social support plus placebo.

what factors reduced cortisol response in the experiment?

Social support or oxytocin.

what condition produced the best stress outcomes?

Having both social support and oxytocin.

what relationship exists between daily social support and stress response?

Higher reported social support is associated with lower cortisol responses.

what does this suggest about social support?

Social support improves the ability to cope with stress.

what neural circuit is proposed for social buffering?

The PFC regulates the ACC and amygdala to reduce stress responses.

what endocrine response is decreased through PFC regulation?

Activity of the hypothalamic-pituitary-adrenal (HPA) axis.

what hypothalamic region is involved in stress responses?

The paraventricular nucleus of the hypothalamus.

what biological mediators may influence social buffering of the HPA axis?

Oxytocin, dopamine, serotonin, opioids, epinephrine, and norepinephrine.

what factors shape the effectiveness of social buffering across development?

Early-life social experiences.

what two biological mechanisms mediate social support effects on stress?

Oxytocinergic functioning and PFC-based safety signaling.

what does OT stand for in social neuroscience?

Oxytocin.

what does vmPFC stand for?

Ventromedial prefrontal cortex.

what does Epi stand for?

Epinephrine.

what does NE stand for?

Norepinephrine.

what is the flip side of social bonding studied in social neuroscience?

Aggression.

what evolutionary purpose does aggression serve?

Establishing dominance hierarchies.

what is the benefit of dominance hierarchies?

Animals no longer need to fight for resources repeatedly because roles are established.

what environmental factor affects stress levels in hierarchies?

Stability and predictability of the hierarchy.

what effect does a stable hierarchy have on individuals?

Individuals cope better with the environment.

what is offensive aggression?

Aggression initiated by the individual starting a fight.

what is defensive aggression?

Aggression in response to provocation.

what is direct aggression?

Outward aggression such as physical violence or yelling.

what is indirect aggression?

Social aggression such as gossip or exclusion.

what is physical aggression?

Aggression involving physical harm.

what is psychological aggression?

Aggression involving emotional or social harm.

what brain region in rodents is known as the hypothalamic aggression area?

Parts of the anterior hypothalamus and ventromedial nucleus of the hypothalamus.

what does VMHvl stand for?

Ventrolateral portion of the ventromedial hypothalamus.

what happens when the VMHvl is stimulated?

Many animals attack another animal.

what experimental manipulation is used to isolate aggression responses in animals?

Using an anesthetized animal so only the experimental animal’s behavior is measured.

what behavior occurs when animals are presented with a glove stimulus?

Animals show high aggression toward the glove.

what percentage of animals attacked an anesthetized but unmoving animal after VMHvl stimulation?

About 60%.

what percentage attacked an anesthetized but moving animal?

About 100%.

what species is known for strong aggression in laboratory studies?

Hamsters.

what social housing recommendation is common for hamsters?

They are usually kept as solitary pets because they are aggressive.

what neuropeptide is implicated in hamster aggression?

Vasopressin.

what brain region is targeted in vasopressin aggression experiments?

The hypothalamic aggression area.

what behavior is measured after vasopressin injection?

Biting frequency.

what effect does vasopressin injection have on male hamsters?

It increases aggression.

what unusual sex difference exists in vasopressin aggression research?

Female hamsters show the opposite effect.

what is c-FOS?

An indirect measure of neural activation.

what pattern of c-FOS activation is seen in aggressive animals?

Increased activation in aggressive animals and in the ACC.

what brain regions are associated with aggression in humans?

Amygdala, hippocampus, basal ganglia, anterior cingulate cortex, dorsolateral prefrontal cortex, and orbitofrontal cortex.

what challenge exists in studying aggression in humans?

Ethical and methodological limitations.

what types of murder were compared in aggression research?

Predatory murder and affective murder.

what is predatory murder?

Planned, controlled homicide.

what is affective murder?

Crime of passion driven by strong emotions.

what neural pattern is seen in predatory murderers?

Higher prefrontal cortex activation.

what neural pattern is seen in affective murderers?

Reduced ability of the PFC to regulate aggressive impulses.

what does the PFC normally do during aggression?

Regulates and suppresses aggressive responses.

what experimental design was used to study moral decision making in aggression?

A 2×2 design involving violence versus compassion toward humans versus aliens.