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234 Cards in this Set

  • Front
  • Back
1. What are six misconceptions that people have about sleep?
1. Sleep in order to dream (REM sleep is most important)
2. We incorporate environmental stimuli into our dreams
3. Dreams don't run in real time
4. Some people just don't dream
5. Sleep walking and/or talking is a manifestation of our dream
6. Dreams are an extension of life working out its problems
2. Why do some people say they never dream?
If you don't wake up during a dream or right after it ended, you won't remember the dream and hence say you never dreamed.
3. When does sleep walking and talking occur and what causes this to happen?
Both happen during early stages of sleep when you are not dreaming

They are caused by impulsed that activate the cortex during slow wave sleep
4. How does the modern activation synthesis theory describe dreaming?
This theory states that dream content reflects the cerebral cortex's inherent tendency to make sense of, and give form to, the random signals it receives from the brain stem during REM sleep
5. What are lucid dreams?
Dreams in which the dreamer is aware that he or she is dreaming and can influence the course of the dream
6. What are the two major theories regarding the question "why do we sleep?"
Recuperative Theories of Sleep

Circadian Theories of Sleep
7. According to recuperative theories, generally what is the purpose of sleep?
The purpose of sleep is to recuperate or restore homeostasis

-Daily activity disrupts the body's homeostasis so it must be reset, which is done during sleep
8. What is some general evidence for recuperative theories of sleep? How can this evidence be explained
Sleep more after you've been sleep deprived.

Make up for lost sleep in order to restore balance
9. What are two specific recuperative theories of sleep?
1. The restorative theory of sleep

2. Elimination theory of sleep
10. According to the restorative theory of sleep, what is slow-wave sleep necessary for? What is REM sleep necessary for?
Slow wave sleep is necessary for the body to recuperate

REM sleep is important for brain recovery/recuperation
11. What evidence is there for the calms of the restorative theory of sleep?
1. Data shows that during slow-wave sleep, 80% of tissue synthesis occurs.
2. 80% of total secretion of growth hormone is secreted during slow-wave sleep
3. More brain protein generation occurs during REM sleep (trying to restore balance in CNS)
12. What type of people proportionally have a lot more slow-wave sleep?

Three groups of people...
1. Children during rapid growth periods

2. Adolescents during growth spurts

3. Athletes during times of training
13. According to the elimination theory of sleep, what is the purpose of sleep?
We sleep to allow homeostasis to re-balance by ridding our body and brain of excess stimulation

Daily activity overloads our neural network and the overload has to be purged
14. What happens to our memories during sleep according to the elimination theory of sleep?
During REM sleep there is memory consolidation (get rid of excess)

Hippocampus takes what is important, consolidates it, and store in LTM
15. What are the three general predictions of recuperative theories of sleep regarding sleep deprivation?
1. Long periods of wakefulness will produce physiological and behavioral problems
(cumulative effect will cause break down)

2. Disturbances will worsen as sleep deprivation continues

3. At end of deprivation, you should make up ALL of the lost sleep
16. In reality, what does one experience due to sleep deprivation?
Long periods of wakefulness do produce some physiological and behavioral problems but they are mild

-Not completely incompassitated
17. In reality how do we make up lost sleep?
-Make up sleep in quality not quantity

-Don't make up sleep hour by hour but instead sleep an extra hour or two for two or so nights
18. What is the rebound effect?
Whatever type of sleep you are more deprived of, causes you to have more of that type of sleep

ex. If you miss more REM sleep, than you have more REM sleep
19. What is the basis of circadian theories of sleep?
These theories are based on the premise that sleep is controlled by an internal timing mechanism and is not a reaction to the adverse effects of wakefulness
20. When subjects went into a cave without any light, what was their determined sleep cycle?
Without any cues from earth, the body runs on a 25 hour cycle with about 8 hours of sleep
21. What resets our circadian clock?
22. What is sleep according to circadian theories of sleep?
Sleep is an instinct

An instinctive reaction to sunlight
23. What are two circadian theories of sleep?
Immobilization Theory

Energy-Conservation Theory
24. Based upon the immobilization theory, what is sleep and its purpose?
Sleep is an adaptive response that has evolved to promote safety

Sleep during the times we can't navigate and thus avoid the times of danger
25. What is the point of sleep according to the energy-conservation theory? When was this theory more important?
Sleep provides a period of time when we can conserve our energy

This was more important when we were hunters and gathers because we only ate every 2-3 days
26. Looking at metabolic rates, what support is there for the energy-conservation theory of sleep?
Higher metabolic rates are associated with longer periods of sleep

Those with higher metabolic rates sleep longer to conserve energy or else they'd burn too much energy
27. What are circadian rhythms?
Daily cycles of body functions
28. What is a free-running cycle?
Circadian rhythms that do not depend on environmental cues to keep them on a regular schedule

-Don't have to be learned
-About 25 hrs in a human
29. What are the two effects of REM-sleep deprivation?
1. With each successive night of deprivation, there is a greater tendency to initiate REM sequences

1. The number of awakenings required to deprive a subject of REM sleep increases as the period of deprivation ensue

3. Following REM-sleep deprivation, there is a REM rebound
30. How does sleep deprivation increase the efficiency of sleep?

Four ways....
1. Regain most of lost stage 4 sleep
2. Higher proportion of slow-wave sleep
3. Short sleepers get just as must slow-wave sleep and long sleepers
4. Reducing sleep results in less stage 1 & 2 sleep but duration of slow-wave sleep remains the same
31. What is Bremer's passive theory of sleep?
Theory claims that we are totally passive during sleep and pay no attention to sensory input

-The brain just shuts down in the absence of sensory input
-There is no active sleep process
32. Where did Bremer severe the bain stem in cats? What is this cut called?
Severed the brain stem between the inferior and superior colliculi (separated forebrain from hindbrain)

Cut is called Cerveau isole
33. What was the result of the cerveau isole preparation?
Cut out all sensory input
34. What was the pattern of sleep displayed by the cats of Bremer's experiment?
They displayed continuous slow-wave sleep in their cortical EEGs

Continuous high-amplitude, slow-wave activity
35. How could the cats slow-wave EEG be changed into a desynchronized EEG?
Present strong visual or olfactory stimuli
36. What is a dsynchronized EEG?
A low-amplitude, high frequency EEG
37. Bremer also made an encephale isole preparation which disconnected the brain from what?
An encephale isole disconnected the brain from the rest of the nervous system
38. What was the result of an encephale isole?
It cut most of the same sensory fibers as the cerveau isole transection but did not disrupt the normal cycle of sleep EEG and wakefulness EEG
39. Based upon the cerveau isole and encephale isole transection where is the structure for maintaining wakefulness?
It is somewhere in the brain stem between the two transections
40. Moruzzi and Magoun made a third transection between the first two resulting in what sleep pattern by the cats?
They were always awake
41. What did Moruzzi and Magoun's transection cut through?
The reticular formation
42. What was found when the reticular formation of cats was electrically stimulated?
The sleeping cats awakened and produced lengthy periods of EEG desynchronization when their reticular formation was electrically stimulated
43. Based upon all of these findings, what did Moruzzi and Magoun propose?
They proposed that low levels of activity in the reticular formation produce sleep and that high levels produce wakefulness
44. What is Yerkes-Dodson Law?
A law which states a relationship between arousal and task performance, arguing that there is an optimal level of arousal for performance, and too little or too much arousal can adversely affect task performance
45. What is one complete sleep cycle?
A complete descention and ascension through the four sleep stages and also a period of REM
46. Roughly how long does it take someone to go through one sleep cycle?
90 minutes
47. During which part of the night do you have more slow-wave sleep? When do you have more REM sleep?
Earlier in the night there is more slow-wave sleep

Later in the night more REM sleep is seen
48. What type of brain wave is seen on an EEG when someone is fully alert and thinking?
Beta Waves

-High frequency (15-30 Hz)
-Low amplitude
49. What type of wave is associated with being relaxed but still awake?
Alpha Waves

-Frequency: 8-12 Hz
-Medium Amplitude
-More regular
-Waxing and waning bursts
50. When someone just falls asleep, what type of wave is observed?
Theta Waves

-Frequency: 6-8 Hz
-Medium Amplitude
-Slower than beta waves
51. What are the waves of stage 1 sleep and what percent of time sleeping is stage 1 sleep?
Theta Waves

5% of sleep time
52. What are the waves of stage 2? What makes these waves different from those of stage 1?
Theta Waves

Theta waves have sleep spindles and k-complexes
53. What causes sleep spindles and k-complexes and what are their hypothesized functions?
They are caused by external stimuli

Their function is to prevent waking (negate the sensory stimuli)
54. What are sleep spindles?

What external stimuli causes sleep spindles?
Sleep spindles is a short, rapid burst of a 12 to 14 Hz wave

They are caused by noise
55. What are k-complexes?

What external stimuli causes k-complexes?
K-complexes are a single large upward deflection followed y a single large downward deflection
(long, isolated high A wave)

They are cause by tactile stimuli
56. What percentage of sleep time is spent in stage 2?
45% of sleep time

*stage 2 sleep happens in 20 minute chunks
57. What happens if a person wakes up while in stage 1 or 2 sleep?
They don't feel like they have slept
58. What is stage 3 sleep?

What percentage of sleep time is spent in stage 3?
Stage 3 sleep is a transitional stage where slow-wave sleep begins

It's 5% of sleep time
59. What waves characterize stage 3 sleep?
Mostly Delta Wave
-Low frequency (1-3 Hz)
-High amplitude

Some Theta Waves
50. What is stage 4 sleep?

What percentage of sleep time is spent in stage 4?
Stage 4 is slow-wave sleep

15% of total sleep time
51. What wave(s) characterize stage 4 sleep?
All Delta Waves
52. When does stage 4 sleep mostly occur?
It occurs mostly in the fist 1-3 hours of sleep
53. How are a person's muscles during stage 4 sleep?
-Muscle tension is relaxed
-Lose some muscle tone but not all

-person might snore
-sleep walking can occur
54. How can someone be awakened from stage 4 sleep?

How will they feel if awoken from stage 4 sleep?
Loud noises, real physical contact, saying persons name. stress, and anxiety

Waking up from stage 4 causes grogginess
55. What physiological changes are associated with stage 4 sleep?
Decrease in heart rate, blood pressure, and body temperature

Breathing is slow and rhythmic
56. What are nightmares or night terrors?

When can they occur?
They are short bursts of strong emotional experience that may be accompanied by short visualization
-have no continuity

Occur during stages 3 & 4
57. What is slow-wave sleep necessary for?
Necessary for recuperation (especially for the brain)

Important to restore normal cognitive brain function
58. What are the effects of slow-wave sleep deprivation?

Five symptoms....
1. Tired
2. Sluggish
3. Motor control problems
4. Irritable
5. Long periods of deprivation can cause minor hallucinations
59. What is the main initiating area of the brain for sleep?

Where is this area located?
Ventrolateral Preoptic Area (VLPA)

In the hypothalamus
60. What is the VLPA?

What does it do?
Starting point for sleep, especially slow-wave sleep

It inhibits the cortex in order for relaxation and thus sleep
61. What specifically does the VLPA inhibit?
Inhibits acetylcholingeric neurons on the basal forbrain area

(basal forbrain does not become stimulated)
62. What is associated with the basal forbrain area?
Arousal and REM-sleep

This area releases neurons when one is starting to wake up
63. What is the pathway for arousal?
Pons to

Basal Forbrain to

Cerebal Cortex
64. What triggers waking?
Reticular formation

(reticular activating system)
65. What are raphe nuclei?
Small bundle of neurons in the mid area of the pons in the reticular formation
66. What is neurotransmitter is released by the raphe nuclei?

What does this neurotransmitter do?
Releases serotonin to bring on slow-wave sleep (stage 3 & 4)

Serotonin inhibits that areas in the pons responsible for initiating REM-sleep
67. What does damage to the raphe nuclei result in?
Insomnia because one will hit stage 3 of sleep and wake up

(lack of slow-wave sleep)
68. What is initial stage 1 EEG?
The first period of stage 1 EEG during a night's sleep not marked by a striking EOG or EMG changes
69. What is emergent stage 1 EEF?
Subsequent periods of stage 1 sleep EEG that are accompanied by REMs and a loss of tone in the muscles of the body core
70. What is REM (rapid eye movement) sleep?

What is the brain wave activity during REM-sleep referred to as?
A period of time were instead of reaching stage 1, REM sleep is began

Change in brain wave activity is referred to as paradoxical
71. What wave characterized REM-sleep?

Three types....
1. Small proportion of delta waves

2. Theta waves

3. Alpha waves

*both awake and asleep waves
72. What are the characteristics of REM-sleep?

Five things....
1. Complete loss of muscle tone
2. Light sleep (wake easily)
3. Awake coherent and alert (better than if awake from slow-wave sleep)
4. Stage for dreaming
5. Increase heart rate and respiration
73. What are dreams?
Dreams are story-like images or emotions that progress like a movie or show
74. What are four reasons for why we have REM-sleep?
1. Memory Consolidation

2. Brain Growth

3. Necessary for cortex to have periods of arousal/stimulation

4. Dampen any strong emotions (Freudian work out life's problems)
75. Why is it believed that REM-sleep is necessary for memory consolidation?
Hippocampus (were information is temporarily stored) is active during REM-sleep

If REM-sleep is disrupted, people have poorer memory of the day's events (never formed memory)
76. How have sensory deprivation studies provided evidence that REM-sleep is necessary for cortical stimulation?
Sensory deprivation studies showed that people will have hallucinations if no input is given to the cortex

Thus, if sensory input to the cortex is suppressed, than the cortex will create its own
77. What are the effects of REM-sleep deprivation?

Four symptoms....
1. Mild changes in behavior and personality
2. Anxious, irritable
3. Concentration problems
4. Increase in appetite (weight gain)
78. When will REM-sleep deprivation occur?
If someone only sleeps 2-3 hours a night
79. What is the pathway for dreaming and awakening?
Peribrachial Area to

Locus Coeruleus to

Basal Forbrain to

80. What is the primary neurotransmitter of REM-sleep?
Acetylcholingeric released bby the Peribrachial area
81. What neurotransmitter does the locus coeruleus release?

What does this neurotransmitter do?
Releases neuroepinephrine

Neuroepinephrine excites the basal forbrain releasing acetylcholingeric neurons
82. How does the peribrachial area regulate rapid eye movement?
It sends acetylcholine neurons to the the tectum
83. What does the tectum do again?
Contains superior colliculi which are a group of neurons that cause one to react to moving objects (tracking with eyes)
83. How does th peribrachial area regular atonia?
Release ACh neuron which stimulate the Subcoerulear Nucleus
84. What is the subcoerulear nucleus' role in inhibiting motor neurons to produce atonia?
It stimulates the nucleus magnocellularis of the medulla which inhibits motor neurons
36. What is the active theory of sleep?

How was this theory tested by Moruzzi and Magoun
Sleep is controlled by a brainstem arousal center

Tested with a transect below the brainstem: Encéphale isolé
85. What is the current state of opinion about whether sleep is active or passive?
Sleep is an active, not a passive state

The brain is active during sleep, it’s just doing different things than when awake
(specific neural circuits for sleep in the brain)
What is the reticular activating system?
Neural structure that runs through the brainstem and midbrain

Pons and medulla
86. What is the importance of the tuberomammillary nucleus?
Histamine in the tuberomammillary nucleus (TM) appears important for

These neurons excite basal forbrain to release ACh neurons
87. What is the role of the suprochiasmatic nucleus?
Nuclei of the medial hypothalamus that control the circadian cycles of various body functions
88. What is the difference between hypnotic and anti-hypnotic drugs?
Hypnotic drugs increase sleep

Anti-hypnotic drugs reduce sleep
89. What type of drugs are benzodiazepines?

What can be a result of using them?
Hypnotic drugs

A tolerance develops to the hypnotic effects of benzodiazephines and cessation of them can cause insomnia
90. What are some anti-hypnotic drugs?

How do these drugs reduce sleepiness?
Stimulants (amphetamines and cocaine) and tricyclic anti-depressants

Increase the activity of catecholamines
91. Which type of sleep do anti-hypnotic drugs act upon?
Act upon REM-sleep
92. What effect does melatonin have on sleep?
It influences circadian rhythmicity

Plays role in promoting sleep or in regulating its timing in mammals
93. What is imipramine?
The first tricyclic anti-depressant (anti-hypnotic drug)
94. What is narcolepsy?
A neurological disorder where sleep (or components of sleep) occur during wakefulness
95. What is the primary symptom of narcolepsy?
Sleep attack (just fall asleep)
96. What are sleep attacks?

What do they occur most often?
Sleep attacks are overwhelming urges to sleep anytime
*don't loss muscle tone

Occur most often when one is not overly stimulated (i.e. monotonous task)
97. What are some other times during which sleep attacks can occur?
1. Periods of extreme stress

2. Driving, eating, lecture
98. What component of sleep are sleep attacks and how long do they last?
Slow-wave sleep component

1-10 minutes
99. What is cataplexy?
Recurring losses of muscle tone during wakefulness, often triggered by an emotional experience

-fully conscious and awake, just can't move
100. What component of sleep are cataplexies?
REM-sleep component
101. What is sleep paralysis?
It is atonia that happens when a narcoleptic has just fallen asleep or awoken (not dangerous)

-REM-sleep component were can't move for a couple of minutes
102. What are hypnagogic hallucinations?
When a person wakes up but their dream continues so that it becomes superimposed in the room
103. What component of sleep are hypnagogic hallucinations and with what other symptom do they usually occur?
REM-sleep component

Usually occur with sleep paralysis
104. What medications are used to treat sleep attacks?
Take amphetamines in the morning (catecholamine agonist)
105. What medication is used to treat the REM-sleep components of narcolepsy?

-It enhances serotonin and all other catecholamines by blocking re-uptake
-Suppresses REM-slepp
106. What is REM without atonia?
It is characterized by not losing muscle tone during REM-sleep
107. What causes REM without atonia?
The subcoerulear nucleus does not react to acetylcholingeric neurons

*failure within two brain areas
108. What can happen to someone who has REM without atonia?
They can get up and walk around and act out their dreams
109. What is done to treat someone who has REM without atonia?
Give them some kind of drug to weaken their muscles before going to sleep

Muscles are relaxed so they can't get up and act their dream
110. What does the midpontine section do?
It causes an increase of cerebral wakefulness

ACh neurons from the peribrachial area excite it which stimulates the basal forbrain
124. Why is it believed that females may actually determine the sex of the offspring?
Females may determine sex due to physiological changes at time of conception
-pH of vagina may control which sperm (x or y)
-Body fat of woman may control (strong in animal kingdom)
125. What gene on the Y chromosome is responsible for making the fetus male?

What does this gene code for?
SRY gene on Y chromosome is sex determining sex

It codes for testes determining factor (TDF)
126. What does the TDF do?
It is responsible for the development of testes in fetus
127. What are primordial gonads?
These are cells that every fetus has that are capable of developing into either reproductive system
128. What are the male reproductive ducts called?

What are the female reproductive ducts called?
Male: Wolffian Ducts

Female: Mullerian Ducts
129. What do the testes secrete?

What does this hormone do?
Testes secrete testosterone as they develop

Testosterone helps the Wolffian system to further develop
130. Do primordial cells respond to testosterone?

If not what do they respond to?
Primordial cells do not respond to testosterone directly

They respond a converted form called dihydrotestosterone
131. How is testosterone converted into dihydrotestosterone?
5-alphareductase acts upon testosterone to convert it
132. What other important chemical do the testes secrete?
Mullerian-inhibiting substance
133. Do the Mullerian ducts need hormonal input?
No, they will develop on their own w/o any hormone input
(default system)
134. What is the purpose of Mullerian-inhibiting substance?
It stops the Mullerian system from developing

It withers away the Mullerian ducts so that they die and are reabsorbed by the body
135. What are the gonads?

What hormone levels are highest in each type of gonad?
Gonads are the testes and ovaries and they produce/release hormones to further develop reproductive systems

Testes: higher levels of test.
Ovaries: higher levels of estrogen
136. What are the primary sex characteristics?

When do they form?
Primary sex characteristics are both the internal and external sex organs

They are developed at birth
137. What are the secondary sex characteristics?

When do they appear?
Secondary sex characteristics are physical changes that are a response to increased hormone levels

They appear during puberty
138. Are the male and female brains different?
Hormones do produce some brain differentiations between male and female brains
139. How are male brains different?

Four ways....
1. 15% larger in mass
2. Thalamus (relay station)is larger
3. Corpus collapsum is larger in males
4. Higher level of activity in limbic system and temporal lobe
140. What are two general difference between male and female brains?
-differences in hypothalamus in terms of responding to hormones and their production

-Response to stimulation in cortex is different between male and female brains
141. How is the brain "masculinized?"
Testosterone undergoes aromatization to form estradiol

Estradiol masculinizes the brain
142. What isn't the female brain "masculinized" since they have a lot more estradiol than males?
Genetic females produce alpha fetus protein which deactivates extra circulating estradiol so less estradiol reaches the brain

*there is no alpha fetus protein in males
143. What is the definition of a hormone?
A chemical secreted by a gland that is carried by the blood or lympathic system and affects target organs elsewhere
144. What does the endocrine system consist of?

What is the important pathway in hormone regulation especially for reproductive development?

HPG axis: hypothalamus, pituitary, and gonads
145. What role does the hypothalamus have in the HPG axis?

What specific hormone does it release?
-The hypothalamus is the starting point
-It secretes releasing hormones

-Secretes gonadotropin releasing hormone
146. What do the gonadotropin releasing hormones do?
Travel to the pituitary where they stimulate the release of gonadotropin
147. What are some gonadotropin hormones released by the pituitary?
FSH (follicle stimulating hormone)

LH (luteinizing hormone)
148. In general, what do the gonadotropin hormones do?
They travel to the gonads to stimulate the production and release of hormones by the gonads
149. What does LH do in males?
1. Responsible for maturation and development of sperm

2. Stimulates (increases) the production of testosterone
150. What does LH do in females?
Increases the production of progesterone in females
161. What is the role of progesterone in females?
Pregnancy Hormone
-Helps prepare the uterus for pregnancy
-High levels of progesterone help keep the egg implanted in the utereus
162. When do the progesterone levels begin to rise?

What happens if the levels drop during pregnancy?
Rise after egg attaches (implants) to the uterus

If levels drop a miscarriage (spontaneous abortion) will occur
163. What does FSH do in females?

Two things...
1. Responsible for increase production of estrogen by the ovaries

2. Stimulates the maturation of the ovum in the ovaries
164. What are two other hormones released by the pituitary?
1. Basocrecin (not gonadotropin)

2. Oxitosin
165. What does basocrecin do?
Responds to gonadotropin releasing hormone

1.Constricts blood vessels
2. Regulates rise in blood pressure
3. Regulates body temperature
166. What does oxitosin do?
1. Responsible for controlling contractions during labor (stimulates labor)

2. Increases milk production
167. What does FSH do in males?
Increases sperm in males
168. What are the three classes of hormones produced and released by the gonads?
1. Androgens

2. Estrogens

3. Gestagens
169. What does the androgen testosterone do in males?
Necessary for development of primary sex characteristics and secondary sex characteristics

*also needed for libido and sexual behavior
170. What are the secondary sex characteristics in males?
Further muscle development
Facial Hair
Deepen Voice
Widen chest/shoulder cavity
171. What does testosterone do in females?
Regulates libido and body hair growth
-produced by ovaries
*during puberty, there is increased hair growth due to testosterone
172. What is the important estrogen for females?
Estradiol (most common estrogen)

*produced by both ovaries and testes
173. What does estradiol do in females?
Triggers development of secondary sex characteristics (pelvic widens, breast growth)

Regulates menstrual cycle
174. What does estradiol do in males?
Important for masculinzation of the brain

*if there is no estradiol in males, there is no deficit in sexual reproduction/behavior
175. What is an example of a gestagen?
-both males and females produce it
176. What is the role of progesterone in males?
No idea!!
177. How are hormones regulated?
Feedback mechanism (positive and negative)

-hormones monitor the glands that release them and further back in chain
178. What happens in a negative feedback mechanism?
Level of hormone will stimulate decrease in production and release of hormone

-want to maintain an optimal range (homeostasis) through adjustments
179. In negative feedback what happens when hormone levels rise?

What happens when hormone levels fall?
Increase hormone levels, decrease production/release of hormone

Low level of hormone, produce and release more of hormone
180. What happens in a positive feedback mechanism?
Stimulate more change in the direction of the initial change
181. In positive feedback what happens when hormone level rises?

What happens when hormone level decreases?
High level of hormone stimulates more production/release of hormone

Low levels, reduce production/release
182. In positive feedback what would high levels of estradiol do?
Stimulate the production and release of FSH and LH which in turn stimulate release of more estradiol
(levels get higher and higher)
183. When is a positive feedback mechanism seen?
During first trimester and during puberty
184. Why is positive feedback necessary during the first trimester?
Increase levels of hormones to ensure the internal organs and reproductive system fully develops
185. What are organizational effects?
Organization of reproductive system, during fetal development usually

*internal/external organs develop during first trimester
186. What are activational effects?
Happen after birth, usually during puberty
-activating system
-regulates menstrual cycle and male sexual behavior
187. How are the hormones released in males?
Acyclic basis
-maintained at steady level within a range
188. How do testosterone levels change throughout a male's life?
There is a slight decrease in testosterone levels, but it is still usually above a threshold so they can still reproduce

-keep above threshold and still have sex drive
189. What sexual behaviors are directly related to testosterone?
1. Intromission (penetration)

2. Pelvic thrusting

3. Ejaculation

*testosterone is critical for male sexual behavior
190. What has chemical castration in humans shown?
Chemical castration has shown evidence that if testosterone drops below a threshold there is decrease if not loss of the above mentioned sexual behaviors
191. What happened in rats if testosterone was re-introduced after castration?
Sexual behaviors will come back and stay as long as the rats keep being injecting with testosterone

*works in humans too if problem is too low levels of testosterone
192. What is the most critical brain area for regulating copulating behavior in males?
Medial Preoptic Area (MPA)

*in hypothalamus
193. What kind of feedback is in the MPA?

How does the feedback mechanism work?
Positive feedback loop

When stimulated sexual behaviors are produced (arousal,erection) and the behaviors themselves further stimulate the MPA producing more behaviors
194. What did lesion studies of MPA in rats show?
If lesioned MPA, all sexual behavior was abolished but testosterone levels remain normal (high)
195. How are hormones released in females?
-Cycle cycle (28 days)
-Menstrual cycle
-Starting point is hypothalamus
196. What is the difference between an estrous cycle and a menstrual cycle?
An estrous cycle is not as regular/often as a menstrual cycle

Only humans and some primates have a menstrual cycle
197. When does the menstrual cycle begin?
First day of period
-release of uterus tissue

Hypothalamus releases FSH so follicle can begin to develop
198. How long does menstruation last?

What are hormone levels like during menstration?
Lasts 3-5 days

Low level of all hormones
199. What does the development of the follicle trigger?

How does this mechanism work?
Triggers release of estrogen (estradiol)

Estradiol levels rise so that just before ovulation, the levels peak feeding back onto the hypothalamus
200. What triggers ovulation?
High levels of LH

-Increasing levels of estradiol feed back onto hypothalamus causing sudden urge of LH
201. How long does the peak in LH last?

What happens when they start to drop?
One day (around day 14)

LH drops off and estrogen starts to decrease b/c LH stops maturing of follicle
202. If estrogen levels are not high enough to trigger surge in LH will ovulation occur?
NO, need high enough estrogen levels for ovulation
203. What stimulates the release of progesterone?
An empty follicle stimulates release

-have corpus luteem
204. What happens to the estrogen levels? What causes this?
Estrogen levels rise again (not as high as before) due to corpus luteum
205. When is the most fertile day? Why?
Most fertile 4 days after ovulation because progesterone levels are high so egg could potentially inplant
206. What happens if woman becomes pregnant?
Fertilization triggers a mechanism in the uterus to continue production of estrogen and progesterone
-levels of these hormones go off the chart and remain high throughout pregnancy
207. What happens if the woman does not become pregnant?
The corpus luteum shrivels and is reabsorbed by the body

*this causes a decrease in progesterone/estrogen levels which stimulates the beginning of the cycle again
208. What type of follicle and hormones are present during the preovulatory period?
Primary and then secondary follicle

FSH, estrogen, surge in LH
209. What is present during the ovulatory period?
corpus luteum

estrogen; progesterone
210. What was birth control originally intended to do?
Introduce high levels of estrogen which would inhibit FSH if given early in menstrual cycle (1st few days)

-prevent follicle from reaching maturation
211. How are the birth control pills used presently designed?
-Some still intro high estrogen level early in cycle

-New pills have combination of hormones (more effective)
212. What back up hormone is used in the new pills?

What does this do?
Back up hormone in case follicle reaches maturity is progesterone

Fools body into thinking its pregnant so shut down LH and follicle isn't released (no ovulation)
213. What does plan B deliver?
-steroid hormone that suppresses cortisol levels

It blocks progesterone receptors by binding to them so progesterone levels drop off
214. What helps with sexual reproduction in female animals?

Not sure about hormones
215. How can pheromones affect pregnant animals?
If a new male is introduced, it may cause a spontaneous abortion due to new pheromones
216. What is the Lee-Boot effect?
When female mice are housed together without a male present, their estrous cycle is disrupted
-stop ovulating (not fertile)
217. What happens if a male is introduced?

What does this imply?
If male is introduced, all the females go into estrous shortly after

The presence of males through pheromones regulate the estrous cycle (not there no need to waste energy)
218. What is the Whitten effect (only documented in animals)?
When a single male is housed with a group of females, their estrous cycles become synchronized and more often

*his pheromones synchronize females cycles
219. A woman names McClintock studied the Whitten effect in human females, what did she observe?
Observed that all females on her dorm floor were synchronized with their periods

-she believes this is the closest to Whitten effect
-somewhere in environment that is an alpha male who is in contact with these females
220. What is the Bruce effect? (definite in animals, who knows in human females)
An unfamiliar male coming into a colony will cause the spontaneous abortion of pregnant females
221. What does the new male do when enters the colony?

What happens if he wins?
Male fights over heron

If he wins, all the females go into estrous after aborting so they can mate with new controlling male
*strategy to increase your genes
222. What is the Vandenberg effect?
The presence of a male in the colony accelerate puberty in pre-pubescent females (go into puberty right then)
223. What type of colony is necessary in order to see the Vandenberg effect?
Usually a matriarchy colony

Male only comes around during estrous (mating session)
224. What brain area regulates sexual behavior in females?
Ventromedial nucleus (VMH)
-part of hypothalamus
-regulates receptive sexual behavior in females
225. How does the VMH regulate sexual receptive behavior in females?
VMH becomes stimulated and causes her to go into Lordosis posture
226. What is the lordosis posture?
Female gets down low, arches her back, and flicks tail out of the way
227. What have lesioning studies of the VMH in rats shown?
If lesioned, rats won't show lordosis posture even if they are willing to mate so there is no reproduction
228. On the other hand what do studies stimulating the VHM show?
If VMH is stimulated, rats go into lordosis posture immediately
229. What happens to females with a damaged hypothalamus?
They do not engage in as much sexual behavior
230. What is Androgenic Insensitivity Syndrome?
There is a mutation on the Y chromosome on the androgen receptor gene

*Don't have androgen receptors
231. How does lack of androgen receptors affect fetal development?
Still have intact SRY gene so the testes start to develop but don't fully develop because there are no androgen receptors

*testes still secrete Mullerian-inhibiting substance so female reproductive system is destroyed
232. What is the result of a lack of androgen receptors?

Four results....
1. Normal male levels of testosterone
2. Have small internal testes
3. External genitals of female since they don't need hormonal regulation
4. No masculization
233. Is androgen insensitivity reversible?

How is it treated?
It's not reversible and it can't be treated with hormonal therapy

Treatment is to suppress levels of testosterone and elevate estrogen (adjust to that of female)
234. What role does the adrenal gland have in congenital adrenal hyperplasia?
There is a deficiency in the release of cortisol by the adrenal gland which results in compensatory adrenal hyperactivity and the excessive release of adrenal androgens (positive feedback)
235. What effect does congenital adrenal hyperplasia have on males?

What about females?
In males it accelerates onset of puberty

In females they look like an underdeveloped male at birth (enlarge clitoris and fused labia)

*1 in 1400 live births
236. How are females with congenital adrenal hyperplasia treated?
At 6 months they are given meds that increase cortisol to normal levels thus bringing testosterone down (suppress)

-reset the mechanism and everything operates normally
-not a long treatment
-surgically alter external genitals
237. What is Tuner's Syndrome?

How many does it affect and who?
Its a defect on the X chromosome

1 in every 2000 live births have it

Affects only females b/c males with it don't survive (only have Y chromosome)
238. What is the defect on the X chromosome?
50% with it are XO (missing X)

30% with it a have a normal X and half of a second X (X1/2X)

The rest have a serious mutation on the 2nd X chromosome
239. What are the characteristics of Tuner's Syndrome?
1. Ovarian failure (1% can get pregnant)
2. Short (under 5"1')
3. Broad chest cavity
4. Receding jaw line
5. Small hands/feet
6. Affect cardiovascular system (disease starting in childhood)
7. Prone to kidney disease or failure (esp at young age)
8. Higher incidence of diabetes
*treat usually just symptoms they are prone to
240. Who are the Guevedoces of Salinas?
Genetic males who at birth appear to female (no male genitals, but no vagina either)but during puberty develop into fully functioning males (penis/balls)
241. What is the genetic disorder they have?
They lack 5-alphareductase (don't have gene that codes for it)

Wolffian system goes dormant b/c testosterone can't be converted into dihydrotestosterone
242. Why do they "turn" male at puberty?
Testes pump out testosterone which adult cells can respond to so scrotum grows, testes descend, penis forms, and become fertile males
243. Where is this mostly seen?

Why does this genetic disorder keep being passed on?
It seen in isolated communities (small villages, islands)

People with genetic mutation are seen as sex symbols b/c they can "change their sex" so they reproduce a lot
244. What is ablatio penis mean?
Accidental destruction of the penis