Sex And Stress Flashcards
A stressor is…
Stressful stimuli
A stress response is…
An individual’s reaction to a stressor
Fight or flight … Preparation for a threatening situation
1) body energy reserves mobilised by adrenal gland
2) adrenal medulla secretes epinephrine and norepinephrine
3) adrenal cortex secretes cortisol (a glucocorticoid)
The effect of epinephrine is…
It affects glucose metabolism and muscle stored nutrients become available
The effect of epinephrine and norepinephrine is…
Increased heart rate and blood pressure
The effect of glucocorticoids are…
They convert protein into glucose, makes fats available for energy, increase blood flow, increase behavioural responsiveness and suppress sex steroid hormones.
These are good responses for stressors
Control of glucocorticoids are…
1) PVN of the hypothalamus secretes the peptide CRH
2) CRH stimulates the anterior pituitary gland to release ACTH
3) ACTH enters the general circulate and stimulated the adrenal cortex to release glucocorticoids
Stress is…
A physiological reaction to the perception of aversive events
Health effects of long term stress
Cohen (1953) survivors of concentration camps have poorer health later in life
Theorell (1992) subway train drivers that injure or kill people are more likely to be ill months later
Cobb and Rose (1973) hypertension higher in Heathrow air traffic controllers than East Midlands
Health problems are caused by …
Selye (1976)
Glucocorticoids as they increase blood pressure and damage muscle tissue. This increases infertility and suppresses the immune system. Increases steroid diabetes and inhibits growth
Cognitive effects of stress are…
Higher stress hormones mean more errors made by a rat presented with a cat smell
Development of Gonads (testes/ovaries)
This is the first sec organ to develop.
It has two roles; to produce sperm/ova and secrete hormones.
These hormones have two effects;
Organisation effects - determine sex organs
Activation effects - occur later on
You are unable to determine sex until 6 weeks old
SRY (sex determining region Y) genes on the Y chromosome turn gonads into testes
The development of internal general is
In the 3rd month of gestation, the embryo posses the precursor for male and female sex organs
The Mullerian system is female
The Wolffian system is male. This forms with no intervention
When one withers and dies, a girl is produced
Testes secrete anti-Mullerian hormone which has a defeminising effect and androgens which have a masculine effect
The development of external general
Before 8 weeks external genitals do not differ
No female hormone needed for development of external sex organs
Male sex organs depends on androgen
Money and Ehrhardt (1972) androgen insensitivity syndrome
Genetically male but mutation means that there is no formation of the androgen receptors. Therefore, only the anti-Mullerian hormone has an effect, meaning so masculation takes place and they do not appear male
Warne and Zajac (1998) persistent Müllerian duct syndrome
This is caused by the absence of anti Müllerian hormone or the absence of receptors for that hormone. This occurs in genetic males, the androgen have a masculine effect buy no de feminisation occurs.
They develop both sets of internal sex organs
Turners syndrome is …
The development of an XO foetus. No Y chromosome so testes do not develop but XX is needed to produce ovaries so these are not present either
Develop normal female internal and external genetials but are able to bear children
Andrenogenital syndrome
Caused by a decrease in cortisol released from adrenal cortex, high levels of adrenal androgens.
This has a minor effect in males with early onset of puberty
This has a major effect on females with an enlarged clitoris and fused labia, ambiguous sex organs develop.
Puberty is onset when…
1) the hypothalamus secretes Gonadotrophin-releasing hormones
2) stimulates anterior pituitary gland to release gonadatrophic hormones. Follicle stimulating hormone (FSH) and luteinizing hormone.
In women this produces follicles and enabled menstration (luteinisation) and the ovaries secrete estrogens
3) stimulates gonads to produce their hormones
Hormonal control of sexual behaviour in male rats
A receptive female is nuzzled, sniffed of their genitals and licked, before being mounted.
After 10 0.25 seconds intromissions they ejaculate
In the refractory period the interval between successive rjsculation increases.
If a male is exhausted a new female rejuvenates him
Beamer (1969) the Coolidge effect
10 seconds for 12 ewes. They tried to use the same ewe but the odour gave it away to the ram. The refractory period drops to a low level if the same ewe is used
Hormonal control of sexual behaviour in human males
Bagatell (1994) men who were given GnHR antagonist had a decrease in sexual interest, fantasies and intercourse
This was removed by replacement testosterone.
Thinking about sex leads to increased testosterone
Hellhammer (1985) an erotic film increases testosterone
Hormonal control of sexual behaviour in female mammals
Lordosis moves her tail, stands rigid and raises her hind quarters. Passive.
McClintock and Adler (1978) females rats have an active role. They do quick short hops and wiggle their ears. Irresistible to males rats
Hormonal control of sexual behaviour in human females
Van Goozen (1997) women initiate sex more during ovulation when estradiol levels are high
