hormones and behaviour

Question 1

Berthold

Answer 1

group 1: castration -> canonisation
group 2: castration and reimplanation of testis -> normal male development
group 3: castration and transplantation of testis -> normal male development

Question 2

1950s - Rosalyn Yalow

Answer 2

radioimmunoassay - detect hormones concentrations in the blood

Question 3

Bernstein 1983

Answer 3

fighting for access to females increases testosterone levels in male rhesus macaques

Question 4

what do hormones influence

Answer 4

behaviour

Question 5

hormones

Answer 5

coordinate physiology and behaviour of an animal by regulating, integrating and controlling bodily functions over time
establish onset/offset
adjust behaviour to context

Question 6

individual differences in behaviour may reflect

Answer 6

hormone concentrations
number/location of hormone receptors

Question 7

lock and key mechanism

Answer 7

hormones and receptors interact through lock and key method
once the receptor is bound to correct hormones, receptor is activated and can stimulate downstream effects

Question 8

dual effect

Answer 8

same hormone (LH) that causes maturation also stimulates mating behaviour in many species
dual function ensures mating occurs only when animals have mature gametes available for fertilisation

Question 9

dual effect of LH

Answer 9

LH stimulates gonads to produce gametes and testosterone

Question 10

animals are composed of 3 interacting systems

Answer 10

input systems
integrators
output systems

Question 11

input systems

Answer 11

peripheral NS - receives sensory information

Question 12

integrators

Answer 12

central NS - receives/sends information

Question 13

output systems

Answer 13

effectors eg muscles

Question 14

singing in zebra finches

Answer 14

males sing to attract females and defend territory from intruders
males with better songs hold higher quality territories and attract more females
remove testes -> stops singing
reimplant testes/administer testosterone -> singing resumes

Question 15

input in singing in zebra finches

Answer 15

testosterone alters sensory capabilities
environmental cues that trigger singing are more salient

Question 16

CNS in singing in zebra finches

Answer 16

testosterone changes neural architecture/speed of neural processing in areas of the brain involved in singing

Question 17

output in singing in zebra finches

Answer 17

testosterone concentrations affect muscles of the syrinx

Question 18

hormonally dependent behaviour should disappear when

Answer 18

source of hormone is removed
actions of the hormone are blocked by antagonists

Question 19

what types of behaviour are influenced by hormones

Answer 19

biological rhythms
bonding
dominance hierarchies

Question 20

biological rhythms

Answer 20

regular variations in behaviour which oscillate (repeat regularly)

Question 21

biological clocks

Answer 21

internal systems/processes that maintain biological rhythms

Question 22

zeitgeber

Answer 22

external cues which entrain biological rhythms
light is key zeitgeber for most animals
entrains mammalian circadian rhythm to 24h

Question 23

melatonin - sleep hormone

Answer 23

pineal gland - receives light input from retina
controls production and secretion of melatonin
night - high levels
day - low levels

Question 24

social bond

Answer 24

meaningful and/or enduring relationship between 2 individuals

Question 25

maternal priming - mammals

Answer 25

internal fertilisation and foetal development female parent guaranteed to be present at birth extended care required after birth female directly invests time and energy to in utero development female equipped to provide initial postnatal feeding

Question 26

maternal priming

Answer 26

in most mammals, females don't show spontaneous maternal care - brain first requires priming onset, maintenance and termination of maternal care controlled by hormones hormonal profiles during pregnancy are similar across mammals

Question 27

pregnancy hormones stimulate

Answer 27

oxytocin

Question 28

oxytocin

Answer 28

centrally - increased OT receptors in area concerned with social reward, facilitate olfactory recognition of offspring, stimulates onset of maternal care periphery - OT released from pituitary gland stimulates uterine contraction and initiates milk let down

Question 29

pair bonding

Answer 29

bond between breeding pairs tendency to form bonds can be linked to different hormones

Question 30

pair bonding in females

Answer 30

OT coordinates maternal behaviour and physiology OT receptors activated in reward pathway

Question 31

pair bonding in males

Answer 31

vasopressin important in male territorial scent marking, aggressive behaviour, social recognition vasopressin receptor widely distributed in brain - dominant role in male social behaviour

Question 32

where has the difference between monogamous and promiscuous species been linked to

Answer 32

variation in expression of AVP receptors in male brain

Question 33

transgenics

Answer 33

when gene for increase AVP receptors from monogamous vole is inserted into promiscuous vole, males form partner preferences

Question 34

group living advantages

Answer 34

difficult to distinguish individual from rest of herd greater success hunting in group

Question 35

group living costs

Answer 35

conspicuousness competition for resources social conflict

Question 36

many social groups arranged into dominance hierarchies

Answer 36

unequal mating opportunities and access to resource

Question 37

how do dominants monopolise reproduction

Answer 37

sometimes testosterone - doesn't always correlate with dominance, giving lower ranking individuals T doesn't always improve status

Question 38

what is a potent social stressor that activates hypothalamic pituitary adrenal axis

Answer 38

aggression

Question 39

social stress short term

Answer 39

boost of energy reserves - fight or flight