Week 8 mixture Flashcards by Sara Richmond

________________ a regularly recurrent state of sexual
receptivity during which the female of most
mammals will accept the male and is capable of
conceiving

Estrus:

How well did you know this?

Not at all

Perfectly

Examples of estrus

○ Female hamsters only nice to males during estrus

○ Female baboons have sexual swellings to indicate fertility

How well did you know this?

Not at all

Perfectly

● Human females do not have any obvious signals

estrus to indicate fertility

How well did you know this?

Not at all

Perfectly

○ Humans also have _____________: engage in sexual behavior throughout hormonal cycle

extended sexuality

How well did you know this?

Not at all

Perfectly

Desires during fertility should be inputs__________
○ This is a straightforward prediction from sexual
selection theory
○ Occurs in animals: females will mate with the
__________male when they are fertile

to mating adaptations

“optimal”

How well did you know this?

Not at all

Perfectly

What is the controversy of selection theory when applied to humans

Controversy when applied to humans
○ Humans all look different
○ Humans might not have estrus (obvious physical
signals)
○ Effects on this idea do not always have reliable
measurements
■ Different experiments use different methods

How well did you know this?

Not at all

Perfectly

______________ When fertile, women elevate their preferences

for putative indicators of good genes

ovulatory shift hypothesis

How well did you know this?

Not at all

Perfectly

● Shows that humans are not emancipated from

all hormonal control

Women place a higher priority on specific male
characteristics
○ To pass on good genes to their offspring

How well did you know this?

Not at all

Perfectly

Scent of symmetry study

○ Women at high fertility preferred body odor of more
symmetric males
○ Women at low fertility did not show much preference

How well did you know this?

Not at all

Perfectly

Women’s attraction to their own

partners and other men ___________

changes

throughout their cycle

How well did you know this?

Not at all

Perfectly

○ Woman was more interested in other men

during high fertility if

their male partners was

less sexually attractive

How well did you know this?

Not at all

Perfectly

What are some cue of ovulation

Behavioral: clothing choice, flirtation, body
movement
● Vocal: pitch, attractiveness
● Olfactory: body odors

How well did you know this?

Not at all

Perfectly

Men are picking up on some type of

__________

fertility/ovulatory cue

How well did you know this?

Not at all

Perfectly

○ Challenge hypothesis: in the presence of fertile female, if rivals are present,

then T goes up to potentially fight or
mate
○ Male’s testosterone increased in response to competition
during partner’s high fertility

How well did you know this?

Not at all

Perfectly

women’s hormonal state can have an impact on

her partner’s hormonal state

How well did you know this?

Not at all

Perfectly

Women’s sexual interests change across their cycle

Women place a premium on male attractiveness while they are fertile

How well did you know this?

Not at all

Perfectly

○ Robust upward shift in women’s preference for all purported cues of

genetic quality

How well did you know this?

Not at all

Perfectly

● New studies are examining if other relationship factors

mute or amplify cycle
shifts
○ EX: bondedness with partner

How well did you know this?

Not at all

Perfectly

___________ congenital conditions involving atypical
development of chromosomal, gonadal, or
anatomical sex

DSD: disorders of sexual development

How well did you know this?

Not at all

Perfectly

● Complete Androgen Insensitivity Syndrome

(CAIS)
XY males with mutation in androgen receptor causing
insensitivity
○ Female external appearance, and female-typical gender
identity
○ Internal testes, no ovaries or uterus

How well did you know this?

Not at all

Perfectly

Abnormal number of sex chromosomes →

Turner Syndrome (XO); Kleinfelter Syndrome (XXY)

How well did you know this?

Not at all

Perfectly

Excess androgens (XX genotype) → ___________

Congenital Adrenal

Hyperplasia (CAH)

How well did you know this?

Not at all

Perfectly

___________ the personal sense of one’s own gender

○ Unique to humans

Gender Identity:

How well did you know this?

Not at all

Perfectly

_____________ persistent cross-gender

identification and discomfort with the natal sex

Gender dysphoria/incongruence (GD):

How well did you know this?

Not at all

Perfectly

Embryo begins as __________

biopotential

Sex differentiation occurs due to genes | ○

Sry (XY) → testis | ○ No sry (XX) → ovaries

Males: have what organization and activational effects of testosterone.

organizational period of masculinization in brain due to T → E2 during fetal development ○ Activated in adulthood by high T

● Females: ___________ during organizational period (probably) ○ Activated in_____________

no active hormonal contribution | adulthood by high E2 + progesterone

● Testosterone is converted to estrogens by __________ in many areas of the body

aromatase

Role of E2 in female neural development: ArKO♀. The goal of the experiment was to

examine if there are feminizing effects of E2 on brain development

○ Currently, organization of feminine brain is thought to have _____________

no hormonal influence (lack of T)

● ArKO♀ showed reduced __________ | ○ Compared to wt and heterozygous KO

lordosis behavior

● Female aromatase knockout mice (ArKO♀)

○ Targets aromatase gene ○ Global knockout → no aromatase in any tissues → cannot synthesize estrogen anywhere ○ Estrogen receptors are unaffected; possible to supplement E2

ArKo not exhibiting lordosis showed ○ Demonstrates there is

``` no E2 production to influence activational effect (lordosis) in brain ```

``` Role of E2 in female neural development Estrogen given early post natal showed: WT control showed ________ ArKO♀ ___________ ● WT and ArKO♀ given EB ____________ ```

lordosis (expected) did not show lordosis (expected) did not show lordosis

``` Role of E2 in female neural development Estrogen given prepubertal: WT control and WT with EB showed _____________ ArKO♀ _____________ ● ArKO♀ given EB showed _________ ```

lordosis (expected) did not show lordosis (expected) lordosis

Role of E2 in female neural development. | Based on the prepubertal estrogen experiment

○ EB restored lordosis behavior → activational | effect

Based on the post natal development experiment, | EB likely

masculinized the brain when given during when mice were sensitive to organizational effect

Kisspeptin neurons are a ○ Female AVPV has more kisspeptin neurons than males ○ Organized by E2 during prepubertal period

sexually dimorphic area of the brain

■ Increase kisspeptin neuron population in_________ as E2 increases with development

AVPV

○ Important regulator of GnRH → __________

involved in HPG axis

● Kisspeptin is involved in __________ ○ Activational effect of kisspeptin on a feminine behavior ○ Exact pathway/projections not understood (yet)

lordosis behavior

Female________ has more kisspeptin neurons than males

AVPV

CAIS comparison to robust sex differences in brain

showed the sexually dimorphic areas of the brain

Mental rotation task: sexual difference in brain | activation

○ Men use parietal areas | ○ Females use frontal and temporal areas

● MRI: compare 2 images so the highlighted | areas are

the differences between them

○ A: Control men are more active ___________

(in the parietal | area) than control women

○ B: Control men _______ than CAIS

are more active

_________have similar | activation

○ C: Control women and CAIS

● Female-typical neural activation in _________

CAIS | subjects

○ Females show less activation of____________

left inferior | parietal lobe than men

__________measure directionality of | brain matter structure

FA = fractional anisotropy =

○ Men typically have higher

FA than women

● Similar image comparison to MRIs ○ Men show higher FA than women ○ Men show higher FA than CAIS ____________

○ Women and CAIS have similar FA

Conclusion from CAIS studies: | ● CAIS subjects show

female-typical neural | characteristics

● Suggests that _________ play a predominant role for brain sexual differentiation

androgens, not sex chromosomes,

Female-typical brain microstructure shown in CAIS subjects White matter microstructure

Men > Women Men > CAIS Women ~ CAIS

CAIS comparison to robust sex differences in brain

CAIS=Complete Androgen Insensitivity Syndrome: XY males with insensitive androgen receptor

Hypothalamus’ response _________ is an objective measure of brain function ○

androstadienone

Androstadienone: odorous steroid found in blood, sweat, | semen; mostly secreted by ________ smelling it causes a reaction in __________

males Smelling it causes hypothalamic activation in females | ■

See response in prepubertal children and adolscents → hard wired _____________

sex diff established before puberty

● Sex reversal in adolecent GD: responded ____________ ○ Control girls responded, girls with GD did not ○ Control boys did not respond, boys with GD did

like their | desired sex

Additional studies’ results: | ● Transgender boys and girls showed ____________

intermediate gray matter volume in male/female dominant sexually dimorphic structures

● Transgender women showed ___________

neuropeptide expression (neurokinin-b and kisspeptin) similar to female-typical levels

Individuals with GD possess certain functional brain characteristics typical

of their experienced gender

CAIS subjects demonstrated female-typical characteristics → _________________ play a predominant role in brain sexual differentiation

androgens, rather than | chromosomes,

Mental rotation task:______________

female-typical fMRI

White matter

microstructure: female-typical FA values

Why would a female’s desires be sensitive during their fertility?

○ To pass on the best genes to their offspring. EX: female golden collared manakins want a male who has the fastest roll snap, because it likely shows improved fitness.

● If humans were emancipated from hormonal control, what type of results would we see in the scent of symmetry study?

○ Female response to a male’s scent would have no correlation with their facial symmetry; they would have no preference throughout their entire cycle

● In these studies, why are only naturally cycling females participants?

○ Hormone therapies (like the pill) “flatten” out the hormone cycle so there is no more cycle. They do not have a high fertility phase, and they may not ovulate. These studies would not be able to compare a high vs low fertility phase. Different types of contraceptives have different effects.

● Do female humans have estrus?

○ It seems like female humans (who have natural ovulatory cycles) have extremely subtle estrus cues. Research is still ongoing!

Do ovaries use aromatase?

○ Yes. To make estrogens anywhere you need testosterone to be converted into estrogen by aromatase

● What is a possible conclusion based on the [mouse ArKO study] results?

○ There is a possibility of different critical windows for male/female development. ○ E2 masculinizes the brain during development (during organizational window) ○ Organization for males occurs prenatally, organizational for females occurs postnatally (according to this data)