Biopsychology SEXUAL DEVELOPMENT AND BEHAVIOR

• contains coding for protein (testis determining factor ) (TDF)
• aka SRY protein

groups of cells that both males and females have prior to 6 weeks of fetal development

• cortex-outer part
• medulla-inner part
• both present w the TDF stimulates the development of the male testes (medulla)

have developmemt of ovaries (cortex) female development is default

Contain fetal cells that develop into femal reproductive organs (uterus, vagina, fallopian tubes)

Contain fetal cells that develop into male reproductive organs(seminal vesicles, vas deferesns, prostate glands)

Helps to stimulate the development of the wollfian system

dihydrotestosterone (androgen)

further helps to stimulate development of the wollfian ducts

specific function- hormone that stimulates the external genetalia (penis and scrotum)

released by testes so that it causes the withering away by the mullerian ducts, reabsorbed by the body

• organization effects- setup and differntiate the members of the species once occur cannot be
• revesed

occur later in species that have a really short gestational period (during) week or 2 after birth

• longer gestational periods, happen before birth after
• that developmental and etc are activational

orginazational development

physical characteristcs (internal organs, testses, prostate gland, vagina, uterus, ovaries)

prior to birth

later puberty and adult (activational effects)

physicallydevelop w/ puberty

• females
• breasts growth, widening of pelvic bone, hips, increase in body fat content

• males
• facial and body hair futher define
• and enhance musclinity and femininity of species

• maturationchanges
• really evidentin animals more than humans

more common consistent types of behaviors

hormonal change doesn’t change cyclic

woman acceptable to mating throughout the cycle

• doesn’t regulate the desire animals only
• receptive during mating periods

• hypothalamic-pitutary-gonadalAxis
• HPG
• Pituitary responding to the hypothalamus then to the gonads

• Function:
• 4 f’s
• directly releases posterior pituitary hormones (vasopressin and oxytocin)

• produce in hypothalamus and released in the pituitary
• stimulates releases of anterion pituitary hormines

• gonadotropin-releasing hormone released
• by the hypothalamus in hypothalamus produce oxytoci and etc

• increases
• blood pressure

• changes
• in body temp (raising it)

• -specific determine functions and some still speculative
• determine uterinecontractions (during menstrual cycle)
• build up important in case pregnancy were to occur
• -rise extremely with the onset of labor (off the charts)
• intiates the delivery process
• - stimulates the milk production in lactating females

• speculative
• -btwn attachment formulation
• high post delivery, tends to initiate mother attachment to the offspring love

• -post partum depression
• mom not highly motivated to take care off offspring
• oxytocin levels decreasing not
• understood some other mechanism causes the symptoms and oxy to drop or is the
• oxy levels low

• differences
• is females have higher levels than males
• why women love to cuddle and get strongly attached!

Following sexual behavior

stimulated to be released by the gonadic tropin of the hypothalamus

• produces 2 gonadotropin hormones
• --folliclestimulating hormone (FSH)
• --luteinizing hormone (LH)

• both males and females
• stimulate follicle in the gonads

• males..developing sperm
• females...each follicle has one ovum
• -intiates development of both sperm and eggs in male and females hormones stimulate that gonads to increase production of estrogen

produce and secreted by both male and female

• males...testes to produce testosterone
• females..production of progesterone(pregnancy
• hormone)

• males..regular release of hypothalamic and pituitary hormones rise and falling always stays within range no dramatic increases or decreases,
• steady flow development
• of spem and testosterone =fairly stable

• females-extreme rising and falling, menstrual cycle times peaking and others bottoming out approaching
• ovulation follicle SH starting to rise so can be released and potentially fertilized
• also so the LH surge peak and thought to be the stimulus that causes ovualtion

• --androgen (testosterone)
• --estrogens (estradiol)
• most common estrogen labeled female hormone
• --gestagens
• females: facilitates pregnancy) pregnancy hormone
• helps to stimulate cells of uterus to prepare lining and prepare for pregnancy also increases at higher levels and stay increasing throughout pregnancy
• (responsible for keeping fetus attached during pregnancy) prepares-maintains-nutures
• stimulatesmilk production after birth

• males
• noprogesterone reduces testone levels
• 5 alpha reductase converts testosterone to dihydro-test

• -- organizing
• (development of body, etc) happens during first
• -- activational effect change
• behaviors or stimulate further development of organs, etc
• male and females brains are diff done by development hormones

• when
• developing in 1st trimester testosterone is produced and travels to
• brain.

• Moleculeof testosterone is converted to estradial by aromatase.
• Estradial: is what masculates the brain

• Estradial doesn’t reach the brain
• In females rise of testestorone levels happens after female brain is developed
• Theres is no femininazation of brain ITS DEFAULT

• Three important facts
• Intromition (penetration), Pelve thrust, Ejaculation

• Positive feedback of MPA and sexual activity
• Male ras that were castrated lead to slack of MPA and reduce of testosterone

Gave them injection of testerorone and all behaviors returned. And show sexual behavior towards females

• If you destroy MPA no way to restore function
• Female development

• -breakdown of entrometrium
• -rise of FSH produces primary follicle
• -increase in estrogen levels àdevelops
• -Gratian follicle. The rise and peak of estrogen as a signal to the pituitary release LH
• -LH surge is what causes ovulation
• -Increase progesterone à begin secrete by corpus luteum which is the case that egg originally was
• in. incase prepares uterus for implantation
• -If there is no fertilization corpus luteum withers away, progesterone levels lower and break down of endometrium
• -If there is a pregnancy even after corpus albican withers away the uterus produces progesterone
• -In 7-8 week the placenta produces progesterone at higher levels
• Hypothalamic-Pituitary-Gonadal
• (HPG) Axis

Interferes with the monthly cycle to prevent pregnancy

Interfere witthe normal feedback cycle and levels of the hormones

• Most effective= one that has more than one type of hormone (combination pills)
• --Estrogen and progesterone

• Combo pill
• Estrogen delivered higher levels at the end of the menstrual period
• Estrogen begins to rise 7,8,9 if typical cycle
• Estrogen peak (diagram) interferes with the further level of the follicle

Secondary follicle if it happens to be released its not gonna begin with pregnancy

• Only if cycle
• is normal, if not pregnancy may still occur

• Interferes
• with the maturation of the follicle

• Progesterone
• which blocks the secretion of LH, and reduces chances of

• Before LH
• surge prevent the pituitary from releasing LH (High levels progesterone)

• Secondary
• surge of LH could stimulate LH again

• LH surgery =
• bursting of follicle, ovulation

• If estrogen
• isn’t giving early enough doesn’t stop maturation of follicle have back up of
• progesterone the egg will not be released, will break down and be reabsorbed by
• the body

First formulated for preventing pregnancy, progesterone inhibitor

Uterine lining, and easier for it to plant, and needed to maintain the attachment of the embryo or fetus

Block it so when drop, (typically taken with in 72 hrs) so egg will simply detach, released and excreted in the body when uterine membrane breaks down

Really don’t notice any difference to what will normally be happening

Females housed together w/o presence of male (lab studies)

Normal estro cycle of fertility that may occur doesn’t occur that it may normally occur in the wild

Do not go into heat

• Once introduced into colony will go to their cycle in short pd of time (male introduced)
• Regulated by the presence of a male
• Given off a type of chemical scent, pheromone, cant directly smell
• Females haveolfactory receptors

• Trigger for the hormonal changes and the esters
• w/o male stimulation does not occur

• human females:
• hasn’t been documented, tried to look for it
• problem we are not really living with just females, men in the world

• -Female estrocycles will synchronize and become more frequent in the presence of a male
• -Having male present more female should be prepared to mate and produce offspring
• -Phenomenon in human females as well
• -Martha Mclintock
• Noticed in dorm, all women on the floor began to have periods within days of each other
• Asking ppl that she knew
• Gave girls samples of diff mens sweat and put under their nose and each male synchronized the periods of that paticular group

• Unfamilar male takes over a colony any females that are prego at the time with the ousted
• male they will spontaneously abort

Thought to be regulated by the male pheromones

• Evolution-
• bc need to maximize male efforts should be helping his own efforts, offsprings then other mans offspring

Now available to carry another offspring

Evolved and developedn as a means of maximizing and passing off the genes to another

Malewhen approaches colony and female close to maturing, accelerate to enter puberty, making them fertile and a possible partner

• Sexual Behavior
• Vnetral Medial Nucleus of the Hypothlamous (VMH)

Active and seems to trigger sexual postering (receptive)

Responsible for stimulating the posture

To test it stimulation, implant electrodes and stimulate it electrically

Male approaching, courtship interaction, activates VMH, poster starts

Normal need the males

• Stimulation studies single female no male, stimulate it drops and assumes the position,
• stops and then goes back to normal activity

Anne S (1953)

• Attractive 26 yr old female had no obvious medical dieseaes or problems Married
• diffculty sexually with husband didn’t menstrate typically and having a lot of pain during sexual intercourse Not obvious till married

• Gynecological-
• externally look like a female and vagina only 4cm long and underdeveloped uterus

Determined didn’t have ovaries either

• Gene test XY chromosome, genetically male but looked like female, hormone levels normal levels of a man
• Tumor= developed testes inside abdomen, testes removed and never told the truth, told her she was sterile and they should adopt

• --Mutation
• occurs that prevents the body from responding to androgens,

• w/o
• the ability to respond to testostorone

• internalize
• testes develop early bc Y chromosome is present, has SRY gene producing sex
• determining factor, testes, secrete testorone but rest of cells not responding
• so male wolfian system don’t respond

• mullerian
• inhibiting substance female organs don’t develop bc blocked and wither away
• external female genetalila develop and appear externally to look female

complete AIS

• annes and video experiences
• externallyeverything, genatialia looks female
• internalized testes, no uterus and ovary
• at birth, looks female,
• diagnosis usually at puberty when menstrual period doesn’t occur

incomplete AIS

• muation or variation in how responsive cells are
• some cells and some receptors respond but not as many as should wide range of characteristics and symptoms
• ambiguous gentalia, don’t look completely feminine or completely masculine
• underdeveloped scrotum sac, varying sizes of underdeveloped penis
• diagnosis sometimes given early and confirmed with blood tests
• living with testes typically removed if not high rate of cancer development
• females develop normally with breast and cant have kids no ovaries or uterus beyond
• that health very good

• caused by condition by congential adrenal hyperplasia
• result of low levels of cortisol being produced bc missing enzyme or it is not functioning well

• cortisol hormone
• produced by adrenal glands (one on each kidney)
• related to stress during
• sympathetic activation and stress response w/
• low production find that adrenal glands increase production of androgen,
• testosterone leads to changes in the female genitals
• stress Slide 26

• ACTH
• stimulates the release of cortisol coming from the anterior pituitary
• Thicker line more cortisol there is

• Affect:
• Feeds back on hypothalamus and slows down the ACTH release

• Not immediate though
• Go over the neg. feedback
• Failure in normal feedback mech.
• More stimulation on the adrenal glands
• Lack the enzyme to produce cortisol
• No feed back trigger to slow it down keeps pumping out

• Masculine genitals
• When adrenal gland stimulated testosterone is being released, so increased release

• Males:
• no major effect on the looks of males
• Doesn’t make them more masculine, anger prone or aggressive
• Added: don’t change anything dramatically
• Often will start puberty sooner by a few months or half a year
• More well developed musculatry but not overly developed

• Female:
• Masculinzation of genitals Have fully normal internal organs
• External genetila now slightly masculinized
• Appear to be in btwn male and female
• Clit slightly enlarged (looks like small penis)
• Excess skin pouch or growtn (starting of scrotum)
• Cell growth over vagina

• Doesn’t
• prevent vay jay jay from working tho

• Treated
• Surgery, Usuallyw/in the 3 months of birth
• Infancy; when theres no memory of it, less trauma
• Reduction; of clit and excess skin and cells (cosmetic surgery)

• Individuals
• Begin to take steroids to replace missing cortisol
• Hydrocortisone, Dexamethasone, Synthetic cortisol
• Reestblaish the feedback ACTH levels return to normal
• Stimulation decreases the testorone levels return back to normal
• Low levels of cortisol
• Lead to dehydration and can lead to death
• Drug more for maintaing circulatory and digestive system then the apperance of the genitals
• One out of 18 thousand

• Males:
• become very sick
• Women: seen immediately after birth
• Slide of social behavior of this disease in women
• Can have children but irregular menstrual cycle so getting prego may be tuff

E4

Caused by deficiency in 5-alpha-reductase

• Responsible for acts on testerone to convert to dihydrotestorone (needed to make male
• genitalia (external))

Low level or completely absent

Internal organs develop normally just not obvious during both Very little or any testorone being made

Extreme cases, infant looks female and external genetaila look female at puberty when testorone levels rise everything activated and everthing is developed

• Penis grows scrotum grows and testes descend
• Discoverdn in 1972 dominican republic of Salinas

• Guevedoces= penis at 12
• Father to son father to son 50% chance of son having it
• Fully functional of males so can reproduce

No stigma about it because it’s a natural process there

Pretty rare disorder

Psychologist at john Hopkins

1960’s radical theory nuture not nature makes one masculine or feminine