Hormones and behaviour Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

how do hormones influence behaviour?

A

biological rhythms

eating and drinking

reproductive behaviour

social behaviour

stress

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

the pineal gland

A

unusually, an unpaired structure

in birds and reptiles, can sense light directly through the skull

in mammals acts via cervical ganglia

phasic (cf. tonic) secretion of hormones and other chemicals in cyclic patternshourly, diurnal, monthly, seasonally…

melatonin is important in regulating cyclical functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is melatonin?

A

released almost exlusively at night

provides a signal to track daylength and season

controls the timing of onset of sleep (in humans)

controls breeding condition in seasonally breeding animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

example of melatonin

A

breeding condition in hamsters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

breeding in hamsters in the autumn

A
  1. senses longer autumn nights
  2. pineal gland prolongs nocturnal secretion of melatonin
  3. hypothalamus becomes sensitive to -ve feedback effects of gonadal steroids
  4. less GnRH released
  5. less gonadotropin released, so gonads atrophy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

breeding in hamsters in spring

A
  1. senses shorter spring nights
  2. pineal gland reduces nocturnal secretion of melatonin
  3. hypothalamus becomes less sensitive to -ve feedback effects of gonadal steroids
  4. more GnRH released
  5. more gonadotropin released, gonads swell and animal prepares to breed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is ghrelin?

A

28-amino-acid peptide secreted by cells in stomach epithelium

stimulates feeding

stimulates release of growth hormone (GH) from pituitary

ghrelin-secreting neurons in brain also involved in control of feeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what happens to circulating levels of ghrelin?

A

rise prior to mealtimes and at night

drop following a meal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how do you provoke increased appetite?

A

treatment with exogenous ghrelin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

obese people and ghrelin

A

have lower ghrelin before eating

but following a meal their levels do not drop

→ a ghrelin system unresponsive to feeding and therefore always hungry?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what happens during the mammalian oestrous cycle?

A

Cyclic patterns of gonadotropin secretion (FSH, LH), present only in females, prompted by surge in GnRH (from hypothalamus) above tonic levels

Effects behavioural as well as physiological changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

pro-oestrus

A

follicular development and ovulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

oestrus

A

receptive period during which fertilisation is most likely to lead to pregnancy

sexually active here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Beall and Tracy (2013)

A

N = 124 normally ovulating women, aged 17–47 (undergrad + community samples)

asked on-line what colour shirt they were wearing

classified as high fertility or low fertility based on reported time since last period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Miller et al (2007)

A

recorded tip earnings by dancers in lap-dancing club

dancers provided information on their menstrual cycle and use of hormonal contraception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

types of social behaviour

A

affiliative behaviour

generosity

orgasm

trust

parental care

17
Q

what is oxytocin?

A

a mammalian peptide hormone that acts on the central nervous system

generally associated with uterine muscle contraction at birth and milk letdown

also governs a suite of prosocial behavioursas do analogues (e.g. isotocin) in other taxonomic groups

18
Q

what is parental care?

A

own young

female rats bred for high levels of maternal behaviours have more oxytocin receptors in the central nucleus of their amygdala

female prairie voles that show more maternal behaviour have higher oxytocin receptor density in their nuclear accumbens

blocking these receptors inhibits maternal behaviour

19
Q

what is alloparental care?

A

young of others

neonate female prairie voles injected with oxytocin are less likely to attack novel stimulus pups

neonate male prairie voles injected with an oxytocin antagonist show reduced alloparental care

20
Q

social behaviour in meerkats

A

allonursing

sentinel duty

pup feeding

digging

21
Q

Madden and Clutton-Brock (2010)

A

N = 36 meerkats (28 males, 8 females) injected with oxytocin vs saline control

treatments reversed 3–5 days later

recorded suite of prosocial behaviours

also recorded initiation of aggression

effects only lasted for about 30 mins

22
Q

what is affiliative behaviour ?

A

rodents and meerkats given supplementary doses of oxytocin spend more time in contact with others

‘knocking out’ oxytocin gene of male mice renders them unable to recognise scent of previously encountered female

infusing brain with oxytocin cures this amnesia

23
Q

prairie vole pair bonding

A

monogamous male mates with one female

oxytocin injections promote pair bonding

dense collection of vasopressin receptors

24
Q

meadow vole pair bonding

A

polygynous male mates with multiple females

no pair-bonding

few vasopressin receptors

25
Q

social behaviour in humans

A

trust

generosity

social sensitivity

orgasm

26
Q

Kosfield et al. (2005)

A

2-player economic ‘trust’ game

investor and trustee each receive 12 monetary units

investor chooses to send 0, 4, 8 or 12 MU to trustee

amount sent is tripled by experimenter

trustee chooses how much of total to send back

N = 194 healthy male participants

3 puffs per nostril of oxytocin vs control (double-blind) 50 mins before playing game

Those who received oxytocin made transfers ~17% higher than control group

27
Q

Zak et al. (2007)

A

N = 68 men

‘one-shot’ economic game involving a voluntary donation

given oxytocin vs control via nasal spray

donations were ~80% higher in oxytocin group

28
Q

Marsh et al. (2010)

A

used well-validated set of photos of facial expression

blended with neutral expression to create varying emotional intensity

participants classified expression 35 mins after oxytocin vs control nasal spray

→ oxytocin increases sensitivity to positive emotional expression

29
Q

orgasm

A

plasma oxytocin increases during orgasm—in males and females

plasma oxytocin levels increase during self-stimulated orgasm

oxytocin evokes feelings of contentment, reductions in anxiety and feelings of calmness and security around mate (trust and generosity?)

may indicate that sex promotes pair bonding

30
Q

the endocrine system

A

chemical substance

conveyed in blood

diffuse effect across body

analogue (graded) signal

‘slow’ response (secs or mins)

response persists over time

no voluntary control

31
Q

the NS

A

action potential

transmitted along nerve fibre

targeted effect in specific cell or organ

digital (all-or-nothing) signal

fast response (ms)

responses generally short-lived

some voluntary control

32
Q

both the endocrine and NS

A

Both are communication and control systems

Both take inputs and effect outputs

Both can be influenced by prior exposure (habituation/immunity)

33
Q

the neuroendocrine system

A

Fast initial response

Prolonged action if required

Enables regulation and control of homeostasis

  • CNS
  • ANS
  • SNS and PSNS

Ensures that the appropriate response is given to a stimulus