Study Guide — Unit 2

PSYCH 4092/5092

Spring 2006

Ovarian Anatomy, Human Menstrual Cycle and Oral Contraceptives

1. What are the follicles and corpora lutea of the ovaries?

2. What is happening in the ovary during the follicular phase?

3. What is happening in the ovary during the luteal phase?

4. What is happening in the ovary during ovulation?

*5. What is happening in the ovary during menstruation?

6. What is happening in the uterus during menstruation?

7. What is a primary follicle?

8. What is a Graafian follicle?

9. What is the antrum?

10. What is the liquor folliculi?

11. How many tertiary follicles usually develop in the ovaries during each follicular phase?

12. How many Graafian follicles are usually present in the ovaries during the time of an LH surge?

13. What is the corpus albicans?

14. What is the dual role that LH and FSH play in the synthesis of estrogens?

15. What role do theca interna cells, granulosa cells, androgens and aromatase play in estrogen synthesis in the ovary?

16. Where in the ovary is progesterone produced?

17. What tropic factor controls the production of progesterone?

18. Describe the human menstrual cycle in terms of gonadotropin secretion, ovarian events, estrogen and progesterone secretion, and changes in uterine lining for the follicular phase, the luteal phase and menstruation.

19. What is the primary difference between the currently prescribed oral contraceptives and the original "Birth Control Pill"?

20. What are "combination" oral contraceptives?

21. What is the difference between monophasic, biphasic and triphasic oral contraceptives?

22. What are some androgenic side effects of some progestins?

23. What is the mechanism of action by which oral contraceptives prevent pregnancy?

Neurohormonal Control of Ovulation

1.What is a sexually dimorphic difference between males and females in the neurohormonal control of GnRH secretion?

2. Why do we say that GnRH secretion in females is "cyclic" or “phasic”, but in males is "tonic"?

3. What neural component is required for estrogen induced "positive feedback"?

4. What causes the shift from estrogen negative feedback control of GnRH secretion to estrogen positive feedback control of GnRH secretion?

5. What hormonal event directly stimulates the rupture of a Graafian follicle?

6. Why is positive feedback of estrogens on GnRH secretion important for female reproductive function?

7. Is positive feedback of estrogens on GnRH secretion an example of an organizational effect or an activational effect of hormones?

8. Is the ability of the brain to have a positive feedback response to estrogen an example of an organizational effect or an activational effect of hormones?

9. Can ovulation take place in a hypophysectomized (removal of pituitary) female rat? Why or why not?

10. Can ovulation take place in a male rat that as an adult is castrated and then implanted with an ovary?

Organizational and Activational Effects of Gonadal Steroids

1. What is meant by "organizational" effects of hormones?

2. What is meant by "activational" effects of hormones?

3. Give an example of an organizational effect of a hormone on the nervous system.

4. Give an example of an activational effect of a hormone on the nervous system.

5. What aspect of the rat's rate of development relative to time of birth makes the rat such a good model for studying organizational effects of hormones?

6. What does "altricial" mean?

7. What neonatal manipulation of a male rat will allow that rat to support ovulation of an ovary implanted into the rat's abdominal cavity after puberty?

What is the critical period for this manipulation?

8. What hormone treatments can be given to a new-born female rat that will prevent ovulation after puberty?

What is the critical period for this manipulation?

9. What effect will the following manipulations have on adult rat mating behavior (i.e. will mating behavior take place, and if so, will the behavior be male typical or female typical)?

a. castration of a male rat as an adult?

b. castration followed by testosterone treatment of a male rat as an adult?

c. castration followed by estrogen treatment of a male rat as an adult?

d. castration followed by DHT treatment of a male rat as an adult?

c. castration of a male rat as a newborn?

d. castration of a male rat as a newborn and treatment with estrogen as an adult?

e. castration of a male rat as a newborn and treatment with testosterone as an adult?

f. ovariectomy of a female rat as an adult?

g. ovariectomy followed by estrogen (and progesterone) treatment of a female rat as an adult?

h. ovariectomy followed by testosterone treatment of a female rat as an adult?

. i. testosterone treatment of a newborn female rat?

j. testosterone treatment of a newborn female rat followed by ovariectomy and testosterone treatment as an adult?

k. estrogen treatment of a newborn female rat followed by ovariectomy and estrogen treatment as an adult?

10. What role does the enzyme, aromatase, have in organizational effects of testosterone on the rodent brain?

11. What role does the enzyme, aromatase, have in activational effects of testosterone on the rodent brain?

12. Why do all fetuses have high blood levels of estrogen?

13. What protects the female rat fetus from masculinizing effects of estrogens on neural development?

14. What is alpha-fetal protein?

15. Where is alpha-fetal protein produced?

16. Why doesn't alpha-fetal protein prevent testosterone from entering the male embryo's brain?

17. Do normal adults have significant levels of alpha-fetal protein in their blood stream?

18. Why would you predict that an individual with testicular feminization mutation (TFM) has a "male organized" brain, although female physical appearance?

19. What kind of hormonal challenge (independent variable) could you give to an individual to test whether they had a male or female organized brain? What would be your dependent measure (i.e. what response would you measure?)

20. Describe the steps that must take place inside a testosterone target cell in order for testosterone to produce an effect via estrogen receptors.

21. Describe the steps that must take place inside a testosterone target cell in order for testosterone to produce an effect via androgen receptors.

*22. Why doesn’t the “super androgen” DHT have the same organizational and activational effects in rats as does testosterone?

Sexually dimorphic brain structure and function

1. What is different about the synaptic organization of the medial preoptic area (anterior to the hypothalamus) in male vs. female rat brains (in general terms)?

2. Where is the "sexually dimorphic" nucleus located in the rat brain?

3. How does the sexually dimorphic nucleus differ between males and females?

4. Is the size of the sexually dimorphic nucleus in the rat brain dependent on organizational effects of hormones? Explain.

5. Is there a similar region in human brains that exhibits sexual dimorphism?

6. What is meant by lateralization of brain function?

7. What are some brain functions that seem to be primarily dependent on right hemisphere function vs. left hemisphere function (assume the individual is right handed)?

8. Describe the evidence from stroke patients that indicates that women have less lateralization of at least some brain functions than do men?

9. What is some evidence from neuroimaging studies suggesting that functionally women have less lateralization of language function than do men?

10. What is some evidence from anatomical studies that women have more communication between their two hemispheres?

11. What are the 2 primary commissures of the brain?

12. What is the planum temporale?

13. What is the relationship between the planum temporale and Wernicke's area?

14. What gender differences have been noted at both the "gross" level and at the microscopic level between the size and structure of the planum temporale?

Hormone Effects on Perception, Sensation and Cognition

1. On the average, how do men and women differ in the following sensory abilities: olfaction, taste, audition, vision?

2. What is the evidence for both organizational and activational effects of gonadal steroids on these sensory differences?

3. How do olfactory and taste sensitivity vary in women across the menstrual cycle and during pregnancy?

4. Are there overall gender differences in I.Q.?

5. How do men and women compare on the average when performing verbal tasks, perceptual skills, fine motor skills, quantitative tasks, visuospatial tasks?

6. Are these average gender differences "large" or "small"?

7. What is an example of a visuospatial task?

8. What is the evidence that gender differences in cognitive abilities are hormonally dependent (organizational and/or activational hormone effects)?

9. What effect does Turner's syndrome or congenital adrenal hyperplasia have on visuospatial ability?

Sexual Orientation

1. What is the evidence for differences between homosexual and heterosexual individuals in circulating androgen or estrogen levels as an adult?

3. What is the interstitial nucleus of the anterior hypothalamus?

4. On the average, how did the INAH3 size compare between the 19 gay men, 16 presumed heterosexual men, and 6 presumed heterosexual women in Simon LeVay's study?

5. How may the following factors impact on the interpretation of Simon LeVay's results: Aids, correlation vs causation, determination vs predisposition?

6. Describe one study that found a brain region whose size varies with gender identity.

Male Mating Behavior

1. What is parthenogenesis?

2. What may be "an advantage" of sexual reproduction in contrast to asexual reproduction (resulting in production of "clonal" offspring)?

3. From a teleological perspective, why should the brain's role in sexual behavior be controlled by hormones produced by the gonads?

4. What are 2 phases that male sexual behavior is often divided into?

5. Briefly describe how researchers have devised a way to quantitate male rat mating behavior (see book).

6. What is the evidence that mating behavior of male rats is dependent on activational effects of hormones?

7. Why can treatment of a castrated male rat with testosterone or estrogen restore mating behavior, but not treatment with dihydrotestosterone (DHT)?

8. What is the evidence for activational effects of androgens in the "periphery" (e.g. the penis and spinal cord) which facilitates erection and ejaculation?

9. What tonic effect does the brain have on erection and ejaculation?

10. What has stronger activating effects in the periphery, DHT or testosterone?

11. What kind of receptors does DHT bind to?

12. What kind of receptor is responsible for the activational effects of testosterone on male rat mating behavior?

13. Where in the brain is aromatase located? Is it intracellular or extracellular?

14. For masculinizing effects on the brain, testosterone appears to be a prohormone for what hormone? What enzyme is involved?

15. For masculinizing effects in the periphery, testosterone appears to be a prohormone for what hormone? What enzyme is involved?

Brain Circuitry Involved in Male Mating Behavior

1. What are 4 brain components that have been best characterized as playing a role in regulating male mating behavior?

2. What are the two sensory components of the olfactory system?

3. What are pheromones?

4. What anatomical structure is believed to contain receptors for pheromones? Where is this sense organ located?

5. What subnuclei of the amygdala receive input from the olfactory system?

6. Where do axons of neurons located in the amygdala project to?

7. What is the stria terminalis and the bed nucleus of the stria terminalis?

8. What general effects do lesions of the medial preoptic area/anterior hypothalamus (MPOA), the olfactory system, or the basolateral or corticomedial nuclei of the amygdala have on the 2 phases of male rat sexual behavior?

9. What differential effect on juvenile rats does MPOA lesions have if the rat is then raised in isolation vs. raised along with unlesioned male and female rats?

10. What effect does electrical stimulation of the MPOA have on male sexual behavior?

11. What effect does blocking the nostrils of a male rat have on mating behavior?

12. What is the Flehmen response?

13. Describe a study that illustrates the dissociation between the MPOA and basolateral nuclei of the amygdala in regards to their regulation of the 2 phases of male sexual behavior.

14. What effect does exposure of a male rat to odors from a periovulatory female rat have on electrophysiological measures of his olfactory bulbs and MPOA?

15. What effect does exposure of a male rat to non-female related odors, such as amyl acetate, have on electrophysiological measures of his olfactory bulbs and MPOA?

16. How does castration of a male rat affect the electrophysiological response of the olfactory bulbs and MPOA to female-related and non-female related odors?

17. What effects do dopamine agonists and antagonists have on male sexual behavior?

18. What effects do endorphins and opiates (e.g. morphine and heroin) have on male sexual behavior, and on GnRH secretion?

19. What is the evidence for a direct effect of gonadal steroids on MPOA function that contributes to normal male mating behavior?

20. Are there androgen receptors in the male brain? and if so, where are they located?

21. Are there estrogen receptors in the male brain? and if so, where are they located?

Human Male Sexual Behavior

1. What is some evidence that human male sexual desire and performance is dependent on activational effects of hormones?

2. Does testosterone determine or cause sexual behavior in males?

3. What effect did surgical or chemical castration of sex crime offenders have on sexual behavior?

4. What is meant by a permissive effect of a hormone?

*5. What is the Coolidge Effect? What in general does it illustrate about male mating behavior? (p. 278)

6. What are some experiences that have been reported to temporarily increase or decrease testosterone levels in men?

7. What have baboon studies found about the relationship between testosterone levels and dominance hierarchies?

Female Ovulatory Cycles

1. What is meant by behavioral "estrus"?

2. Why is it believed to not be appropriate to say that women have estrus cycles?

3. Is there evidence for differences in sexual activity/arousal in women throughout the menstrual cycle?

4. What role does progesterone play in reproduction and what is the primary target tissue for progesterone?

5. What triggers a "full blown" luteal phase in the rat? What anterior pituitary hormone is involved?

6. What is pseudo pregnancy?

7. What is meant by saying that ovulation and/or pseudopregnancy is "spontaneous" or "induced"?

8. Give an example of a species that has a spontaneous pseudopregnancy and ovulation.

9. Give an example of a species that has an induced pseudopregnancy and a spontaneous ovulation.

10. Give an example of a species that has a spontaneous pseudopregnancy and an induced ovulation.

Female Mating Behavior

1. Distinguish between attractivity, proceptivity and receptivity.

2. What activational hormonal conditions are necessary for optimal lordosis behavior in the female rat?

3. What biphasic effect does progesterone have on mating behavior?

4. Describe briefly the following social effects on rodent reproductive cycles: Lee-Boot effect, Whitten effect, Bruce effect, Vandenbergh effect.

5. What general effect do male rats have on female rat estrous cycles?

6. What general effect do other female rats have on female rat estrous cycles?

7. Who is Martha McClintock?

8. What is the evidence for social effects on menstrual cycles in women?

9. What evidence does a recent study provide for a pheromonal contribution to menstrual synchrony?

Neurocircuitry Related to Female Rat Sexual Behavior

1. What general effect does the forebrain have on female sexual behavior?

2. What hypothalamic region is especially important for female sexual behavior?

3. What effect does lesions of the MPOA have on female sexual behavior?

4. True or False. Lesions of the VMH affect both proceptive and receptive behaviors.

5. True or False. Lesions of the ventral noradrenergic bundle (VNAB) inhibit proceptive behaviors.

6. Where does the VMH project to?

7. What role does the midbrain central gray play in female mating behavior?

*8. What is the neurotransmitter that is secreted by neurons whose cell bodies are clustered in the locus ceruleus?

9. What is the evidence that estrogen and progesterone have direct activating effects on VMH and midbrain central gray function?

10. What roles do norepinephrine, dopamine, serotonin and opiates seem to play in regulating female sexual behavior?

11. Why may Prozac (fluoxetine) and other serotonin selective reuptake inhibitors have both an enhancing and suppressive effect on sexual behavior?