Psych 110 Experiments - Experiment notes for Dr. David Edwards PDF

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Experiment notes for Dr. David Edwards...

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Psych 110 FALL SEMESTER 2019 First Half INSTRUCTOR: Daivd Edward [email protected]

Guinea Pigs Phoenix, Goy, Gerall, 1959 Mating behaviour in female guinea pigs ●

Inject pregnant female with TP (testosterone propionate) ● Since the dose and time of TP injection were not controlled, there are anatomically virilized females and unmodified female( injected with TP but didn’t look like male)

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All the animals in the study were gonadectomized before testing

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They inject the animals with estrogen and progesterone before testing them for the percent of

lordosis (female typical mating behaviors) ○

Why did they inject TP? What was their intention? ● Normally females will not be exposed to a large amount of testosterone. Males have testes, while females do not. They want to see if give them testosterone will make them anatomically male.

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Why gonadectomized animals? Why inject animals with estrogen and progesterone before

testing them for lordosis? ● They want to control the amount of testosterone, as females do not have testes while males have testosterone. To control the amount of testosterone for both males and females, they gonadectomized (remove their sex glands). ● Lordosis is the reflex of female guinea pigs for sexual arousal, is aroused by estrogens. So exposing them to progesterone increase the percentage. (maximize the percent)

Mating behavior in the male guinea pigs ●

Control males and females and virilized females.

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Gonadectomized all animals as adults, inject them with TP daily for 16 days and tested them on

9 different occasions with sexually receptive females. ● Mean no. of mounts test, Control male 20.5, virilized females 15.4, control female 5.8 . ○ Why did they gonadectomized their subjects? ○ Why did they inject them with TP as adults? What did they find? What did they conclude? 1

Phoenix write about the activational and organizational effects of hormones on behavior. What

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do they mean? Give examples of each of these effects? ■

Organizational effect: anatomically different. (virilized females due to fetal exposure to TP)

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Activational effect of testosterone: activate behaviors (like mounting) the increase dose of

testosterone causes both females and males to be aggressive in behavior patterns.

Mice and Rats Aggressive behaviors , David Edwards, 1969 ●

Control male, control female, female 1 (injected TP started on day 1 of their birth), female 2

(injected TP started from day 10 of their birth) As dose of TP(mg) increases the percent of pairs fighting increases(for control male and female

○ day 1) ■

The critical period for TP about aggressive is right around birth.

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Day 10 castrated males ; day 1 castrated males

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Day 10 castrated males increases percent of fighting largely while day 1 males do not show a

large increase.

Gorski, Gordon,1967, Evidence for morphological difference within the medial preoptic area of the rat brain. ●

3 groups: control female ; female injected 21 days of testosterone during fetal development;

female injected with testosterone 10 days after birth ■

The dose of testosterone is gradually increased every time.

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Results: exposure to androgens during fetal development could cause the nucleus (Sexually

dimorphic nucleus SDN) to be bigger.

Hansan Kohler 1985 ●

Bilateral excitotoxin libateonic acid. Lesions on the medial preoptic area eliminate male mating in male rats.

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## Two more studies see notes page 22

Wood Newman 1995 Integration, notes on page 23

Rhesus Monkeys Phoenix, Goy, Resko, 1968, play mounting and age

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Play mounting for 100 observations of control male, control female, and virilized female during

1 year, 2 years. The frequency of rough and tumble play is statistically higher in males, and for

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virilized females, is in the middle, is really low for females. As they get older, the frequency of plays decreased gradually, (entering puberty, the rough and tumble play gradually transferred into serious sexual behaviors）

1988 Goy et al. LAF,EAF ●

25 days of injections. Early androgenized female(mothers injected with TP on days of 40-64 of

pregnancy[168 days]), Late androgenized females(115-139 days of pregnancy) , control male and female. ● Study the mean episodes of Rough and Tumble play ( mating behaviors in rhesus monkeys) ● Mean episodes of R and T play ( M>LAF>EAF=F) ● Mean episodes of play mounting (M>LAF=EAF>F) ●

Conclusion: Different behaviors for different species have different critical periods and the period could be different to the anatomy. Their behavior changes were not because they are anatomically different, but depends on the time they were exposed to androgens.

1985 Pomerantz and Goy (Female-typical sexual behavior) ● Given estradiol in silastic capsules implanted under the skin before and during the weeks of testing. ● Control male(castrated in one month after birth), control female, virilized female (prenatally androgenized female from mothers injected with TP 42-95 days of pregnancy) ○ Count the instances of ,sexual solicit for female (hand slap and head bob, glance, slidle) ○ Calculate the percent of the test period that the experimental animals spent in close proximity to males. ○ Since female typical sexual behaviors in rhesus monkey depends on activational influence of estrogens (estradiol) so exposing them to estradiol before test and during test will enlarge their overall possibility of showing those behaviors. ●

Results: Virilized female and male were the same in respect to showing less solicits and staying away from males.

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1988 Pomerantz and Goy _Prenatal androgen exposure and maletypical mating ●

Control male (castrated within 1 month after birth), control female, virilized female ○ All females were gonadectomized. All animals were injected TP s adults before and during test for male typical sexual behavior. ■ Trio test, 1 experiment animal with 2 sexually receptive females(given estrogen) ■ Giving them choice, so that maximize the results ○ Intromission and ejaculation were rarely observed. ■ (castrated within one month after birth and until testing in adulthood) ■ Since the level of TP kept high for 5 months, removing testes 1 month after birth, they lack the exposure of TP for 4 months, so fail to ejaculate--Organizing effect of TP.

Humans Imperato-McGinley study(1974- 1997) ● males with deficiency in 5-alpha-reductase (the enzyme responsible for the conversion of testosterone into dihydrotestosterone(DHT). ○ (DHT-> prostate, penis, scrotum tissue) ● Testes has inhibiting Mullerian duct system. ● He was raised as a female, but when he enters adolescent he transformed gender identity from female to male.

Ken Zucker 1996, Melissa Hines 2001, survey with CAH ● Result: 30 % of CAH girls are bisexual or homosexual.

Berenbaum& Hines, 1992, ACH patients ACH patients: Their deficiency of 17 hydroxyl enzyme caused their cortisol level to go down, and since cortisol inhibit ACTH (adrenocorticotropic hormone), they have no hormone to suppress the production of androgen precursors. Due to more exposure to androgen, Baby girls with this condition are born with a penis and scrotal tissue. They are genetically female, so they do not have sry gene to have testes determining factor, so that they do not have testis, or Mullerian inhibiting substance, so they have normal ovaries and normal mullerian duct differentiation. They do not have Wolffian duct structures, and they have neither prostate gland nor bulbourethral gland. 4

○ The lack of Wolffian duct differentiation?? they should develop wolffian duct due to exposure to testosterone and dihydrotestosterone. So infer from Dr. Edward, the precursors they produced might largely transferred into dihydrotestosterone rather than testosterone. (See the study by ImperatoMcGinley, DHT is in charge of the outer organisms, penis, scrotum tissue, while inner organs like glands are dependent on testosterone) ○ (play time of boy and girl typical toys) ■ The data prove the statistical significance of the different time boys spent on playing boys toys, girls toys. (Sex difference prove that)

Auyeung , 2009, Amniocentesis ● They took liquid from the mother’s womb to test the fetal testosterone level of babies and match the results with the PSAI score. ○ (Fetal testosterone level and PSAI score-Preschool Activities Inventory Score) ● In general, boys had higher PSAI scores than girls. These results presumabily reflect real sex differences in the way boys and girls act when they are around the age of eight years. ○ The author assayed testosterone in the amniotic fluid to provide a measure of fetal hormone exposure. In humans, testosterone enters the amniotic fluid via diffusion from fetal skin and later via fetal urination. For males, testosterone is produced by the testes. Female produced little amount of testosterone in ovaries and adrenal gland.

Lamminmaki et al , 2012 ● Urinary testosterone at different timepoints in full term boys and girls, during the first six months after birth scores at fourteen months. ○ PSAI score matches with testosterone AUC (area under the curve) ■ Boys: r=.54, p>0.1 ■ Girls: r=.05, not statistically significant (due to so little testosterone) ● Testosterone measured in infancy predicts subsequent sex-typed behavior in boys and girls.

Brain Structure Difference in Sex Allen and Gorski, 1989, INAH

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Interstitial Nucleus of Anterior Hypothalamus(INAH) ○ Since the PO-AHA influences gonadotropin secretion, maternal behavior, and sexual behavior in several mammalian species, these results suggest that functional sex differences in the hypothalamus may be related to sex differences in neural structure. ● Results: The size of INAH 3 in men is about 2.8 times bigger than women.

Simen LeVay, 1991, sexual orientation ●

Heterosexual men, heterosexual women, homosexual men (HIV medical record) ○ Examine their mean volume of INAH 3( Interstitial Nucleus of Anterior Hypothalamus)

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Results: homosexual men is stastistically smaller than that of hetereosexual men (even a little smaller than women) *Women’s orientation is not recorded in the medical record.

Byne 2001 ○ Experimental setup is similar to the upper one. ○ BUT means for groups with differences are not statistically different.

Allen Gorski 1992 , anterior commissure ● AC (anterior commissure)/ brain weight (since men brains are bigger than women) ○ AC is known to be smaller in women’s brains. ● Heterosexual man, heterosexual women, homosexual men(medical records) ●

Heterosexual man is statistically smaller than that of heterosexual women and homo men.

Zhou, Swaab, 1995/2000, BNST (Bed nucleus of stria terminalis) ● Bed nucleus of stria terminalis is supposed to be larger in men than women. ● BNST: central subdivision of of Bed nucleus of stria terminalis ○ A female-sized BSTc was found in male-to-female transsexuals. ● The size of the BSTc was not influenced by sex hormones in adulthood and was independent of sexual orientation. ● The first to show a female brain structure in genetically male transsexuals and supports the hypothesis that gender identity develops as a result of an interaction between the developing brain and sex hormones.

Julia Heiman, 1966, sexual response to explicit depictions of humansexual activity ● Measure sexual responses in physiological way ● Man: Penile strain gauge; Woman: vaginal photoplethysmograph 6

● Audio, description of explicit sex; romantic; neutral ○ Result: women and men are similar in respect of what turns them on ( they were both receptive to explicit sex, not romatic or neutral)

Chivers, 2004, Video tapes of explicit sex (handout) ● Genital arousal is measured. (Measure the parasympathetic system, sexual arousal, penile strain gauge, vaginal photoplethysweigh) ● Categorical Specific: specifically aroused to men-men sex or women-women sex ○ Men is categorical specific (hetero more aroused to female female; homo more aroused to male male) ○ Women is not categorical specific (equally aroused for men to men and female to female) ○ Transsexual( male to females) are categorical specific. (also include stright and gay) ● This sex difference has to do with gender (genetically) and exposure to testosterone during fetal development, given that homosexual females have not exposed to significantly larger amount of testosterone. ● This sex difference (categorical specific or not) has nothing to do with gender identity, or sexual orientation. ● So for CAH patients, congenital adrenal hyperplasia, theoretically, they, being exposed to testosterone during fetal development would respond to categorical specific like males.

David Buss, 1992, Sexual infidelity measured by electro dermal response. ● Electrodermal response: measure the electron current of the skin, sweating, sympathetic nervous system, sweat gland. ● Emotional infidelity; love infidelity ○ men are more distressed by sexual fidelity than emotional or love infidelity ○ Women are more distress by emotional infidelity.

Michal Kosfeld and Zak 2005, OT and trust. ● Investor and trustee. Investor was given a chance to give money to the trustee. The trustee will have triple amount of money by the investor

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● Groups were given Oxytocin or placebo ( salt solution) (oxytocin will go through olfactory bulb into the brain)

● Trust Experiment ○ The trustee will give back money according to their own will. ○ Result: Investor with OT tend to invest significantly more money. They trust the trustee more.

● Risk Experiment ○ The trustee will give back money according to computer algorithm (random gambling, no trust involved) ○ Result: Investor with OT and PL invest about the same amount. ○ Risk- taking is related to the level of testosterone. ● Conclusion: OT promotes trust but risk aversion free with money.

● A graph to analyze the amount of money trustee given back to the investor. ○ OT and PL have no significant difference. ○ Barreza and Zak 2011 . OT increase generosity BUT for another charity study. Among 48% of people want to donate money were given OT. OT increases charity 48%. ○ Conclusion: OT promotes trust but not make people more generous or want to do things for you . (prosocially) ○ Hypothesis: Since the amount of OT will increase when trustees feel they were trusted, the receptors have already been filled by OT so adding more OT will have no effect, due to the lack of receptors.

Diamond and Sigmundson 1997 David Reimer born with phimosis--foreskin would not retract. Easy fix--circumcision. Surgery went wrong and entirety of penis was removed and couldn't be surgically restored. Parents decided to go through with sexual reorientation surgery and raise David Reimer as a girl. Early reports were of success and became general standard procedure for microphallus (1/4 normal size penis). Not realize that David Reimer was uncomfortable with gender identity until 1997. At 14, situation was explained to him--David Reimer was furious and relieved. Fully identified as male after that point. Surgically created a penis, cut off female body parts, had sexual relations as a male. Despite marrying eventually killed himself due to severe depression and familial issues. THREE FALSE ASSUMPTIONS 1. boys/girls psychologically neutral 2. cannot grow up psychologically normal without normal sexual organs

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3. the single most important determinant in gender identity is socialization experiences as an adolescent

Sheeps Roselli et al. 2004, sexual orientation ○ To ascertain the sexual orientation of ram ■ Female oriented rams mount and ejaculate for ewe, while male oriented rams only mount and ejaculate to rams. ■ Precopulatory activity of heterosexual rams do to ewe more than rams, while for homosexual rams, they show precopulatory activity more to rams. ○ Ovine Sexually dimorphic nucleus (oSDN) ■ Ewes, female-oriented ram, male-oriented ram ■ Measure the Volume of oSDN and Number of neurons. ● Female-oriented ram>male-oriented ram>ewes

Roselli et al 2011 (Surprise result, Notes on p11) ○ Control male, control female, early TP female, early TP male, late TP female, late TP male. ■ Gave TP to pregnant female sheep early (30-60) ■ Late (60-90 days) ○ The volume of oSDN of control female, early TP female , and !!! early TP male are statistically smaller than that of the others. ○ Surprisingly!! Early TP male’s oSDN is small ---->The critical period for organizational effect of oSDN is relatively late. ■ Early excessive exposure to TP suppresses the development of oSDN.

Prairie voles Jesse Williams et al. 1994, bonding in female in respect to the effect of OT(oxytocin) ● Bonding: whether she chooses to stay with him for a longtime->Commitment ● Female put with a male for 6 hours, not enough time for mating to occur. ● Results: with CSF (cerebrospinal fluid, placebo) she stays the same time for stranger and partner, but with an injection of OT, she stays significantly longer time with the partner. ○ Bonding is associated with mating and an increase in Oxytocin. 9

Insel and Hulihan 1995, mating and bonding in female ● Estrogen treated female were put with a male for 24 hours- mating occurs. ● With CSF, she stays long time with partner than the stranger. With OTA (oxytocin antagonist) she stays the same time, with vasopressin antagonist she stays long time with partner. ● Conclusion: OTA is responsible for developing bonding in female prairie voles.

Winslow et al, 1993, mating and bonding in male ● Male put with an ovariectomized female for 24 hours (no mating occur) ○ CSF, OT, same time ○ With Vasopressin, the percent of test with the partner is bigger than stranger. ● Male put with an estrogen-treated female for 24 hours (mating occur) ○ CSF and OTA, spend more test with partner ○ VPA, spend similar time . ● Conclusion: Oxytocin is responsible for bonding in females while vasopressin is responsible for bonding in males. ● Different exposure time to testosterones probably lead to this sex differences.

Hamsters Murphy, Schneider 1970, bilateral removal of olfactory bulbs eliminate mating in male hamsters Winans and Powers 1977, vomeronasal nerves and main olfactory system work together to regulate mating in male hamsters. ● Cutting the vomeronasal nerve→ 44% X mate; 56% mate ● 56% 其中 Use zinc sulfate 的 hamsters 都无法 mate 了; 没有 vomeronasal 也没有 main olfactory 的 hamsters 没法 mate ● 剩下两个 saline treatment(control) 可以 mate ● 只用 ZS, 只 damage main olfactory system, 留下 Vomeral nasal organ， 可 以 mate. ○ Zinc Sulfate kills main olfactory receptors in nasal septum. ● Some hamsters totally dependent on bulbournasal system, some less dependent, both systems( vomeronasal and olfactory system) help regulate mating 10

● Conclusion: the destruction of the vomeronasal system irreparably reduces arousal necessary for mating in some hamsters but in other males sufficient arousal is mediated through the olfactory system, in conjunction with other sensory inputs. Removal of the olfactory input in these animals eliminates the behavior.

Lehman etal 1980, bilateral removal of medial nucleus of the amygdala eliminate sexual behaviors in male hamptors. Olfactory ROUTE MOB-> AOB->MNA->BNST/MPOAH CNA_->MNA->BNST/MPOAH

Other Questions posed in the email: -

What is the sexually dim...