sex Flashcards
proceptive
referring to a state where a female advertises her readiness to mate through species typical behaviour
sexual attraction
women peaks during fertility - for most species coapulation is not possible without the womens cooperation
mysterious
can also be because of same place at the same time
first stage in bringing male and famales together
animals emit stimuli that attract members of the opposite sex
also many associate it with being ready to reproduce
appetitive behaviour
actively doing something that makes sex more probable
for humans it could be getting dressed up and going to the club
appetite for sex
behaviours designed to attract mates (proceptive)
consummatory behaviour
corresponds to copulation or coitus in many species
postcopulatory behaviour
characteristic post-coital behaviours, often associated with diminished sexual appetitie for some period of time
cleaning up
refractory period
for awhile after copulation, males and/or females will not mate again
varies greatly between species
coolidge effect
refractory period is considerably shortened if a refractory animal is provided with a novel partner
- will mate sooner if with a new partner
especially true of males, but also some females
Heat/estrus
a period of greatly increased sexual receptivity
receptivity is low or absent outside of estrus
often coincides with ovulation, or whatever conditions are necessary for reproduction
at the same time as ova being spread
female often the one to choose when coapulation takes place
some species will not have sex outside this period
copulatory lock
remarkable adaptation - male’s penises swell and lock into place for awhile
can be a firm lock
maximizes the probability of paternity, minimizes copulation by other rival males
ring doves
male courts female through bowing
femle wing flips if sight of good male causing hormonal changes in female - if seperated by glass and can only see each other
makes male excited, so he starts making a nest
makes woman excited and she is ready to incubate and feed, egg lay
each stage has a hormonal correlate that is largely controlled by the behaviour of the other mate
lordosis
a female’s receptive posture
four legged animals in which hindquarters are raised and the tail is turned to one side, facilitating intromission by the male
estrogen
secreted at high levels at beginning of ovulatory cycle and gives rise to proceptive behaviour
peaks before ovulation
stimulate production of testoterone
progesterone
sudden increase before ovulation maximizes proceptive behaviours and lordosis (receptive behaviour)
ovariectomy
eliminates sexual responses
lordosis can be partially restored through estrogen replacements
behaviour requires both hormones
vaginal code (cervicohypothalamic projection)
need penis hitting the cervix - mechanical stimulation - will signal to hypothalamus to get ready for pregnancy
pseudopregnancy
females mated with castrated males (receiving replacement testosterone) get the usual vaginal/ cervical stimulation, and hence undergo the hormonal changes (prolactin releases)
such females show all the concomitants of pregnancy for quite some time afterwards - their bodies appeared to be fooled into thinking that they are pregnant
induced ovulation
females of some species do not ovulate until mating occurs
such animals tend to be continually receptive or easily become receptive under the correct conditions
ie/ ovulation is stimulated when rats have their flanks stimulated
induced puberty
female shrews do not even go through puberty until their first copulation - no secretion of gonadotrops until first coapulation
they will go through puberty and get pregnant all in one fell swoop - quite economical
behavioural estrus
occurs when an animal has been exposed first to estrogen and then progesterone
periaqeductal gray
lesions greatly diminish lordosis
Human Ovarian cycle
- FSH stimulates maturation of follicle
- secretion of estrogen from maturing follicle causes LH secretion
- LH secretion causes ovulation, then causes ruptured follicle to be a corpus luteum
- corpus luteum secrete estrogen and progesterone, preparing uterus for pregnancy
- without fertilization production of sex hormones declines, and menstruation begins again
in rats the luteal phase has to be induced, in humans it is spontaneous
testosterone
drives most of male sexual behaviour
- males who fail to produce testosterone in puberty, do not show signs of sexual interest, additional testosterone also shows no effect
testosterone in a rat
castrated males stop ejaculating within weeks
castrates stop mounting
t is cleared within hours, yet caustration effects are slow, suggesting structural changes
replacement of missing T restores the copulatory behaviour pretty much immediately
this is an example of the activational effect of testosterone
permissive function of testosterone
the presence of testosterone in a male allows sexual behaviour but does not cause it
presence of testosterone changes sexual activity under the right circumstances
only a tiny amount of T is needed to maintain fully normal sexual behaviour. increasing it does not increase sexual behaviour or change it in any way
excess T produced by males underlies agression and territorial in rats. linear relationship between T and agression. but not in humans
duds and studs
duds make T, and giving them extra T does not turn them into studs
castrated male rats given replacement T are much the same, a tiny does of T restores the studs to their former studliness- and no amount of T will studlify a Dud
serotonin may be responsible for dudliness
kinsey report
first descriptive info
revelations about masturbation, homosexuality
first realization that humans are engaging in this
masters and johnson
studies the physiology and phenomenology of human copulation
among other things gave physiological evidence of female orgasm being very similar to the male orgasm.
for orgasm, men ejaculation, women coapulation
describes the physiological correlates of each phase in coapulation: increase excitement, plateau, orgasm and resolution
described huge variability in sexual positions among hums
INAH3 (3RD INTERSTITUAL NUCLEUS OF THE ANTERIOR HYPOTHALAMUS)
much larger in men than women
much larger in heterosexual men than in homosexual men
suprachiasmatic nucleus
involved in rhythms
differs between hetero and homo men
homosexual men have reported different light/dark levels
effects of sexual behaviour on CNS
castrates with T implant
copulators paired with female for 30 days
non coapulators - no access to femal
result: experience of having sex changed the brain.
- SNB diffs between groups
- must be due to behaviour, not hormone
gay man hand
index finger and ring finger same size
gay woman hand
ring finger bigger than index