Biopsych exam 2

Estrous cycle

The cycle of sexual receptivity in female rats and guinea pigs and in many other mammalian species, which suggests that female sexual behavior in these species is under hormonal control

Metabolic tolerance

Decrease in amount of drug that reaches the target site. Liver starts to adapt to the drug and produces more enzymes to metabolize it. As a result, you become more tolerant to the drug b/c liver is more efficient, so it can't reach specific target organs. Ex: alcohol hydrogenase, an enzyme that breaks down alcohol and can produce hangovers

Secondary sex characteristics

Development in puberty and a spike in hormones. -males: testosterone increases, secondary activation of body hair, deeper voice, increase in muscle mass -females: estradiol increases, secondary activation of menstrual development, widening of pelvis/hips for birth, breast development

Primary sex characteristics

Development occurs in utero that differentiates males and females. Includes physical development of external genitalia & hormones that have an organizational effect

Circadian rhythms

Diurnal (daily) cycles of body functions. It's a regulated, repetitive function within the nervous system and body. We have a number of biological clocks for releasing hormones, regulating alertness, etc. Happens at certain times of the day, but these times can vary based on individual differences

Agonist studies

Dopamine agonists increase ICSS, like cocaine and amphetamine use

Hormonal effects (rats)

Driven by pheromones which are released by males and females. -Lee-boot effect: in a colony of female rats w/ no males, there's decrease in LH so estrous cycle decreases. Females stop ovulating until male's introduced -Whitten effect: in a colony of female rats w/ males present, estrous cycles synchronize. Caused by pheromone given off by sweat, found in humans as well -Bruce effect: unfamiliar male enters a territory and overtakes female harem from current male. All females spontaneously abort, an evolutionary effect that protects offspring. Unfamiliar male will kill off offspring produced by current male -Vandenbergh effect: pheromone from urine of sexually dominant male causes prepubescent females to start estrous cycle

Tolerance

Drug tolerance is a shift in the dose-response curve to the right. So in tolerant subjects: -the same dose has less effect, therefore a decrease in drug response -a greater dose is required to produce the same effect

Positive reinforcement

Drug-taking behavior is followed by a pleasant outcome (euphoria, relaxation, etc.). It feels good, so we seek out the drug again

Stimulants

Drugs whose primary effect is to produce general increases in neural and behavioral activity. Includes cocaine and amphetamine

SSRIs & SNRIs (narcolepsy treatment)

-typically taken later in the day -helps to reduce episodes of REM sleep components (cataplexy, sleep paralysis, hallucinations) -people may have to wake up in the middle of the night to take more

Tricyclic antidepressants (narcolepsy treatment)

-usually taken if SSRIs & SNRIs don't work -typically taken later in the day -helps to reduce episodes of REM sleep components (cataplexy, sleep paralysis, hallucinations)

Wolffian system

6 weeks after fertilization, both males & females have 2 complete sets of reproductive ducts: this and female Mullerian system. This system is male and has the capacity to develop into the male reproductive ducts. Under influence of testicular testosterone, this system develops and Mullerian-inhibiting substances causes the Mullerian system to degenerate

Mullerian system

6 weeks after fertilization, both males & females have 2 complete sets of reproductive ducts: this and male Wolffian system. This system is female and has the capacity to develop into the female ducts. In the absence of testosterone, this system develops into female reproductive ducts and the Wolffian system fails to develop

Morphine (opiate)

Major psychoactive ingredient in opium. It's a narcotic drug that relieves pain & induces feelings of well-being. It's a restricted drug & highly addictive

Sodium oxybate (narcolepsy treatment)

-CNS depressant that reduces excessive daytime sleepiness and cataplexy -may still experience sleep paralysis & hallucinations if no other medication is taken w/ it -taken at night, immediately before bed -second dose 3-4 hours later (middle of the night)

Stimulants (narcolepsy treatment)

-acts as orexin agonist -acts as dopamine & norepinephrine agonist (reuptake inhibitor) -typically taken in the morning, helps to reduce daytime sleepiness

GABA (slow wave sleep)

-acts on all arousal areas of the brain -found in ventrolateral preoptic area (vlPOA) -suppresses alertness and behavioral arousal, and promotes sleep

Gonadal hormones (HPG)

-androgens: testosterone most common -estrogens: estradiol most common -gestagens: progesterone most common, also called the pregnancy hormone. If levels drop, then pregnancy ends

Adenosine (slow wave sleep)

-builds up in extracelluar space during the day so that levels are at their highest right before you fall asleep -peptide released by neurons during high levels of metabolic activity throughout the day -increases activity (excitatory effect) in the vlPOA so that more GABA is released -it breaks down during the night b/c less activity compared to the day, so excitatory effect decreases & less GABA is released

Male brains

-cerebral hemispheres are 10-15% larger -higher percentage of white matter and cerebral spinal fluid -larger hypothalamus -larger & more reactive amygdala: more aggressive behaviors and will react faster in stressful situations

Additional symptoms of narcolepsy

-difficulty staying awake -REM sleep intrudes into waking state -skip SWS or it's very short, and goes directly into REM sleep from waking -sleep is fragmented: disrupted by periods of waking, which may contribute to sleep attacks during day -1/2000 people have it, but it's usually very mild. People may take a short nap and then they're productive afterwards, not serious enough to cause problems -hereditary disorder: gene on chromosome 6, influenced by unknown environmental factors (could be triggered by environmental toxins)

Norepinephrine (arousal)

-found in locus coeruleus, which is in the pons -plays role in attention and vigilance -possible role in behavioral arousal: decrease in behavioral arousal when locus coeruleus is damaged, increase in behavioral arousal when locus coeruleus is stimulated -levels high only during wakefulness: lower levels during SWS & lowest during REM -project to and impact: cortex, thalamus, hippocampus, cerebellum, pons, medulla

Serotonin (5-HT, arousal)

-found in raphe nuclei, which is in the medulla pons near caudal or tail end (posterior) of reticular formation -levels high during wakefulness -levels lowering as descending towards REM -cortical and behavioral arousal -plays a role in activating behavior: if raphe nuclei is stimulated there's increased pacing, chewing, and grooming in rodents -project to and impact: thalamus, hypothalamus, cortex, hippocampus, basal ganglia

Acetylcholine (arousal)

-found in the dorsal pons & basal forebrain -plays role in arousal of cerebral cortex -levels high during wakefulness and REM -involved in cortex and hippocampus arousal. Hippocampus deals w/ consolidation of new memories, and this neurotransmitter enables this. Memory formation occurs during sleep!

Histamine (arousal)

-found in tuberomammillary nucleus, which is in hypothalamus -levels high during wakefulness -levels low during SWS and REM -implicated in control of wakefulness and arousal -project to and impact: cortex, thalamus, hypothalamus, basal ganglia, basal forebrain

Mesotelencephalic dopamine system & addiction

-lab animals administer microinjections of addictive drugs into various parts of mesotelencephalic dopamine system. Drug increases dopamine so more pleasure -microinjections of drugs lead to development of conditioned place preference. Rats go to compartment where drug is administered -addictive drugs increase rewarding effects of ICSS. Non-addictive drugs that don't produce dopamine shows no ICSS behavior -lesions and antagonists decrease rewarding effects of addictive drugs

Female brains

-larger ventral prefrontal cortex (social cognition & interpersonal judgment), increased development in puberty and fully develops at 21-22 yrs vs. males at 25-26 yrs -more neural connections -higher percentage of gray matter -larger hippocampus: better at memory tasks -more serotonin, dopamine and GABA

Physical effects of alcohol

-liver disease: alcoholic hepatitis or inflammation of liver, and cirrhosis or replacement of healthy tissue by scarred tissue -increased risk of cancer -coronary heart disease -malnourishment -neurological disorders: Korsakoff's Syndrome, which includes vitamin B deficiency, confusion, disorientation, and long term memory loss

Ventromedial nucleus (VMN)

-located in hypothalamus -involved in regulation of female sexual behaviors in rodents -stimulates arousal through estrogen. Estrogen not as impactful on sexual behavior in humans vs. animals -causes lordosis, a specific position in rodents and animals during copulation -if this structure is damaged or no estrogen, decreased libido & sexual behavior. Female rodents will reject males & attack him violently. No lordosis

Theories of addiction

-physical dependence theory -positive incentive theory -incentive sensitization theory

Restorative theory (recuperation theory of sleep)

-repair & regeneration of the body during sleep -increase in growth hormone occurs, about 80% is released -necessary for optimal functioning of physiological functions: lack of sleep can increase obesity, cardiovascular disease, depression & anxiety -restoration of brain: concentration, formation of new memories, cognitive tasks. You can become grumpy/irritable when you lack sleep

Orexin (arousal)

-stimulates other arousal areas of the brain -found in lateral hypothalamus -levels high during wakefulness -low during restful wakefulness and all sleep stages -increase activity in the brain stem (medulla, pons, cerebellum) and forebrain arousal systems (dorsal pons, basal forebrain, etc.)

Conditioned tolerance experiment

-subjects received 20 injections of alcohol and then were tested in the same environment. Result: tolerance to the hypothermic effect alcohol -subjects received 20 injections of alcohol and then were tested in an environment different from the one in which they had received the injections. Result: no tolerance to hypothermic effect of alcohol

Gonads

-testes: in males -ovaries: in females Primary function is production of sperm cells and ova (eggs). Each have 23 chromosomes (46 total)

Fatal familial insomnia

A genetic disorder, consists of several months of not sleeping and then you eventually die. Neurons in the dorsal part of the thalamus slowly die due to the bending of proteins. You can't go into a deep sleep, you drift in and out

Melatonin

A hormone that's synthesized from the neurotransmitter serotonin in the pineal gland. The pineal gland regulates circadian rhythms and seasonal changes in reproductive behavior through its release of this hormone

Cocaine (stimulant)

A stimulant that's the most commonly abused. Consumed by snorting or injection. Impure residue is called crack, which is a cheaper smokable form. Users feel self-confident, alert, energetic, friendly, outgoing, fidgety, and talkative. Less desire for sleep & food. Withdrawal (relatively mild): negative mood swings & insomnia. Exerts its effects through blockade of dopamine transporters so that dopamine is removed from synapses and transfers back to presynaptic neurons. Can also experience nausea, tremors, psychotic behavior, and even seizures

Fertilization

After copulation (sex), sperm cell fertilizes ovum to form a zygote, which contains all the info necessary for the normal growth of a complete adult organism in its natural environment. Has a total of 46 chromosomes

Withdrawal syndrome

After significant amounts of a drug have been in the body for a period of time, its sudden elimination can trigger this adverse physiological reaction. These effects are always opposite to the initial effects of a drug. Drug exposure leads to the development of adaptive neural changes that produce tolerance by counteracting the drug effect. With no drug to counteract them, the neural adaptations produce withdrawal effects opposite to the effects of the drug

SRY gene

Also called the sex-determining region of the Y chromosome, which contains the coding for testis-determining factor (TDF, or SRY protein). 6 weeks after conception, the primordial gonads of XX and XY individuals are identical. If no Y chromosome is present, the cortex of the primordial gonad develops into an ovary. But under the influence of the Y chromosome, the medulla of the primordial gonad develops into a testis. Either the medulla OR the cortex will develop based on the gene

Slow wave sleep

Also known as deep sleep. We spend 40-50% of the night in this stage. The less time we spend in this stage, the worse our bodies and brains become. Hard to wake someone out of this stage, so you may be disoriented when you wake up or it takes you longer to recognize your alarm clock is going off. Calling person's name is more likely to wake them up vs. shoving them or poking them -seems essential for survival (i.e., fatal familial insomnia) -lack of sleep associated w/ various disorders (cardiovascular disease, diabetes, etc.) -consolidation of declarative memory: factual memory, contains all facts and info you learn, like in class

Chronotype

Alters with age -young: night owls, performance is worse in the morning. Peak arousal is around 9-10 am, so starting classes later is beneficial! 7-8 am is still considered night/sleep time, so kids can't perform well -older: morning larks, performance is best in the morning

Aromatase

An enzyme that converts testosterone to estradiol. Estradiol is responsible for the process of aromatization or masculinization.

Circadian clock

An internal timing mechanism that is capable of maintaining daily cycles of physiological functions, even when there are no temporal cues from the environment

5-alpha reductase

Converts testosterone (responsible for internal male genitalia) to dihydrotestosterone (responsible for external male genitalia)

REM sleep & development

Babies and toddlers sleep the most. They sleep for about 16 hrs, w/ 8 hrs of both REM and NREM sleep. As we get older, we spend less time in SWS. From day 1 till about 6-7 yrs old there is very prominent brain growth and more REM sleep. As we grow older, we spend less time in REM sleep, and there's a decrease in brain growth. Brain growth doesn't completely stop, but it's not as rapid as in kids

Mesotelencephalic dopamine system

Begins in the midbrain, so it starts in the mesencephalon and ends in the telencephalon. It's a system of dopaminergic neurons. Includes the nigrostriatal pathway & mesocorticolimbic pathway

Recuperation theories of sleep

Being awake disrupts homeostasis (internal physiological stability) of the body in some way and sleep is required to restore it. -restorative theory -elimination theory

John Money

Believed nurture (instead of nature) was more important in gender differences. Socialization determines gender!

Cocaine spree

Binges in which extremely high levels of intake are maintained for periods of a day or 2. Users become increasingly tolerant to the euphoria-producing effects of cocaine. Larger doses often administered, spree ends when cocaine is gone or when it starts to have serious toxic effects: sleeplessness, tremors, nausea, hyperthermia, and psychotic behavior. Risk of loss of consciousness, seizures, respiratory arrest, heart attack, or stroke. Repeated use sensitizes subjects to its motor and convulsive effects.

Buerger's disease

Blood vessels become constricted, especially in blood that supplies the legs. Gangrene can set in, which can involve amputation of the foot and eventually the whole leg. Typically found more in male smokers. Caused by nicotine

Passive theory of sleep

Bremer proposed that sleep happens when there's lack of stimuli, such as lack of light, sound, etc. He did experiments on cats by lesioning out the cerveau isole (isolated forebrain), or cutting the pons from the forebrain. After surgery, cats would sleep and could only be awakened by loud sounds or strong smells. He also lesioned out the encephale isole (isolated brain), or separating the entire brain from the spinal cord. Cats that recovered from surgery had normal sleep-wake cycles. Goal was to cut off all somatosensory input to prove that sleep was a passive process

John/Joan case

Brian Reimer and his twin brother were supposed to be circumcised, but Brian's penis was completely burned off in the process. Mother took him to John Money, who said Brian should be raised as a girl. He grew up as Brenda and received hormone treatments to become more feminine. But he never felt like a girl and was still very masculine in appearance. After finding out what happened, he stopped hormone treatments and started becoming a male. Later changed his name to David and committed suicide

Mifepristone (birth control pills)

Called RU-486. It's a progesterone receptor blocker that causes the lining of the uterine wall to shed. It's taken in 2 doses, results in immediate loss of pregnancy. Must be taken within 49 days or less since last menstrual period

Heroin (opiate)

Can easily penetrate the blood-brain barrier. More potent analgesic vs. morphine and less likely to induce nausea and vomiting. Euphoric rush includes intense abdominal, orgasmic pleasure that evolves into a state of serene, drowsy euphoria.

Conditioned tolerance

Environmental cues activate a compensatory response that counteracts the drug effect. Tolerance effects are maximally expressed only when a drug is administered in the same situation in which it has previously been administered

Dose-response curve

Once you reach the maximum dose & effect of a drug, increasing the dose does not produce a stronger effect. This is the maximum point at which no more medicine can be administered. Going beyond this point can lead to overdose and toxicity

Energy conservation theory (adaptation theory of sleep)

Following survival activities, periods of inactivity are a good way to conserve energy. If we're constantly active, we burn off more energy. We spend 1/3 of our lives sleeping to conserve energy

Medial preoptic area (MPA)

Found in hypothalamus, must be stimulated by testosterone in order to regulate typical male sexual behavior. If damaged in rodents, then 3 sexual behaviors go away starting from ejaculation, thrusting, and loss of interest in copulation w/ female or intromission, the act of the penis penetrating the vagina. If damaged in male humans, they have trouble performing but don't always lose interest

Sleep spindles

Found in stage 2 of sleep. Short bursts of 12-14 Hz. High frequency, low amplitude. Kids & young adults have more than older adults, which is why older adults wake up frequently in the middle of the night. They can't sleep through the whole night.

K complexes

Found in stage 2 of sleep. Sudden sharp waveforms, has a large negative wave (upward deflection) followed immediately by a single large positive wave (downward deflection). Kids & young adults have more than older adults, which is why older adults wake up frequently in the middle of the night. They can't sleep through the whole night

Theta wave

Found in stages 1 & 2 of sleep. Moderate frequency, low amplitude (high wavelength), 3.5-7.5 Hz. Indicates sleep

Delta wave

Found in stages 3 & 4 of sleep, or slow wave sleep. High amplitude, low frequency, 1-2 Hz. The largest and slowest EEG waves. In stage 3 these waves start to appear, 60% ____ & 40% theta waves. In stage 4 it's 90% ____ w/ occasional theta waves. It's a deeper sleep, so less likely to talk and move

Brain mechanisms (LH orexinergic neurons)

Found in the lateral hypothalamus. During sleep/waking flip-flop, this neurotransmitter can activate brain stem and forebrain arousal systems, releasing arousal neurotransmitters & resulting in alert waking state. The motivation to remain awake (exercise, coffee, etc.) stimulates this neuron, and this activation holds the flip-flop on. W/ every action potential in these neurons, there's more firing in the arousal areas. Inhibition of GABA release!

Alpha wave

Found in wake stage. Fairly regular, low amplitude, high frequency of 8-12 Hz. It's a relaxed wakefulness, so it can occur while you're daydreaming, meditating, doing yoga, or watching TV

Beta wave

Found in wake stage. Irregular, low amplitude, high frequency of 13-30 Hz. You're awake and interacting w/ the environment

Sleep/waking flip-flop

GABA causes this flip-flop! -when the flip-flop is in the wake state, the arousal systems are active and the vlPOA is inhibited -when the flip-flop is in the sleep state, the vlPOA is active and the arousal systems are inhibited

Shepard Siegel

He created the conditioned compensatory response model. He first tested morphine tolerance, which is a learned response. Later tested heroin conditioned tolerance & overdose. 3 experimental groups: -same-tested & different-tested groups: daily injections of increased heroin -control group: daily injections of saline On test day, all groups given very large dose of heroin: -same-tested group: given heroin in same room as daily injections -different-test group: given heroin in a different room as daily injections -control group: given heroin for the first time

Physiological effects of alcohol

Heightened activity of inhibitory neurotransmitter GABA, which leads to feelings of relaxation by toning down nervous system activity. Senses become clouded, balance & coordination suffer. Higher doses affects parts of the brain that regulates involuntary vital functions: heart rate, respiration rate, and body temp. Can cause hypothermia!

Comparative analysis of sleep

Humans sleep for an average of 8 hours a day. Smaller animals sleep more, while larger animals sleep less b/c of risk of predation while sleeping. Larger animals need to be more vigilant at night. Smaller animals also have a higher metabolic rate, meaning they burn more energy so they need more sleep, whereas larger animals have a smaller metabolic rate.

Mullerian-inhibiting substance

In the 3rd month of male fetal development, the testes secrete testosterone and this substance. It causes the Mullerian system to degenerate and the testes to descend into the scrotum. If this substance isn't released by the testes, then the Mullerian & Wolffian systems will develop. You have both male & female parts, so you're a hermaphrodite

Mapping studies

Indicates that areas that support ICSS are typically part of mesotelencephalic dopamine system. Rats press lever b/c it feels good

Mentalis muscle

Located in the middle of the face, muscle completely relaxes in any stage of sleep. Used to detect when someone has fallen asleep

Alcohol

It's a depressant b/c at moderate to high doses it depresses neural firing. At low doses it can stimulate neural firing and facilitate social interaction. Genes may be associated w/ alcoholism. Moderate doses: various degrees of cognitive, perceptual, verbal, and motor impairment, & loss of control. High doses: unconsciousness and risk of death from respiratory depression. Facial flush produced by dilation of blood vessels. It's also a diuretic, which increases urine production by kidneys. Livers of heavy drinkers metabolize it faster. Produces extensive brain damage Withdrawal: headache, nausea, vomiting, tremulousness or hangover

Process C

It's our circadian or wake drive. Peak alertness is at 7 am, which then decreases as it heads towards 11 pm

Plan B (birth control pills)

Known as Levonorgestrel or progestin, which is synthesized in the lab and mimics progesterone. Must be taken within 3 days of unprotected sex (during preovulation to stop LH surge or after egg has been released) in an attempt to stop ovum release. You have a very short window, so if taken after 3 days and egg has been released, fertilized and implanted in uterine wall then you can't stop pregnancy

Drug-self administration paradigm

Lab rats or primates press a lever to inject drugs into themselves through implanted cannulas. They readily learn to self-administer intravenous injections of drugs to which humans become addicted. Once they've learned to self-administer an addictive drug, their drug taking often mimics in major respects the drug taking of human addicts

5-alpha reductase deficiency syndrome

Lack of sufficient levels of 5-alpha reductase, which can't convert testosterone into dihydrotestosterone. Individuals are born as females, but once they hit puberty they become males. They've always had testosterone & Wolffian system, but this lack of 5-alpha reductase couldn't trigger dihydrotestosterone

Smoker's syndrome

Long-term tobacco use leads to chest pain, labored breathing, wheezing, coughing, and a heightened susceptibility to infections of the respiratory tract like pneumonia, bronchitis, lung cancer, along w/ cancer of the mouth, esophagus, kidneys, pancreas, bladder, and stomach. Also risk of CVDs

Electroencephalogram (EEG, physiological measure of arousal & sleep)

Measure of the gross electrical activity of the brain. It's recorded through large electrodes attached to scalp. Scalp signal reflects sum of electrical events throughout the head. These events include action potentials and postsynaptic potentials, as well as electrical signals from the skin, muscles, blood, and eyes.

Preovulatory

Menstrual cycle begins on 1st day of cycle, not the day after. Lasts about 28 days. FSH is responsible for creation of follicle, which holds the ova or eggs. It decreases around days 6-7 b/c there's enough to create Graafian follicle which holds mature/viable eggs for pregnancy. Estrogen production increases from days 5-11 to create uterine wall. This rise impacts hypothalamus & pituitary, along w/ secondary wave of FSH. Both stimulates brief increase in LH, which triggers ovulation so mature egg is released from Graafian follicle

Active theory of sleep

Moruzzi and Magoun thought regulatory input from pons must be responsible for sleep. They electrically stimulated parts of the pons to show that the brain is actively working during sleep and that not all somatosensory input is cut off. Cats w/ a midcollicular transection (cerveau isole preparation) displayed continuous slow-wave sleep in their cortical EEGs. Lesions at the midcollicular level damaged the core of the reticular formation, but left the sensory fibers intact, producing a cortical EEG indicative of continuous slow-wave sleep. Electrical stimulation of the pontine reticular formation desynchronized the cortical EEG and awakened sleeping cats. Cats w/ a transection of the caudal brain stem (encaphale isole preparation) displayed a normal sleep-wake cycle of cortical EEG. These findings suggest that a wakefulness-producing area was located in the reticular formation between the cerveau isole and the encephale isole transections

Narcolepsy

Most widely studied disorder of hypersomnia. Symptoms include: -sleep attack: uncontrollable urge to sleep during the day. Primary symptom to diagnose -cataplexy: loss of muscle tone due to emotional stimuli. Lasts for few secs-1 min. Still conscious of surroundings -sleep paralysis: inability to move as one is falling asleep or waking up. There's a disconnect/delay in brain activation & REM on/off switch. Can occur even w/o disease due to illness, stress, medication -hypnagogic hallucinations: dreamlike experiences during wakefulness. Eyes are open but hallucination is occuring b/c of a disconnect/delay in brain activation & REM on/off switch. Can occur even w/o disease due to illness, stress, medication

Negative reinforcement

Not the same as punishment, which decreases behavior. This reinforcement is a negative correlation: drug-taking behavior is followed by removal of an unpleasant event (withdrawal, reducing anxiety). It relieves us, so we seek out the drug again

REM rebound

Occurs when sleep deprived, you rebound by spending most time in this stage for the first 2 or 3 nights. With each successive night of deprivation, there's a greater tendency for participants to initiate REM sequences. As deprivation proceeds, participants have to be awakened more and more frequently to keep them from accumulating significant amounts of REM sleep. This suggests that REM sleep is regulated separately from the amount of slow-wave sleep and that REM sleep serves a special function.

Postovulatory

Once ovulation occurs and a mature egg has been released from Graafian follicle, estrogen, LH, and FSH all decreases. There's no need for the creation of a new follicle once an egg has been released. The corpus luteum (empty follicle) triggers a second rise in estrogen in correspondence w/ this stage. If fertilization occurs within 4 days of ovulation, uterine implantation of egg occurs and progesterone spikes to maintain pregnancy (along w/ estrogen). If progesterone suddenly decreases, there's an immediate abortion/miscarriage

Organizational effects in rats

Once rats are born, testosterone and estradiol start to organize and differentiate the baby rats into male or female. W/o testosterone to stimulate MPA, then no typical male sexual behaviors. If a baby female rat is injected w/ testosterone, then it'll develop into a male and exhibit male sexual behaviors. If a baby male rat is injected w/ estrogen, then it'll develop into a female and exhibit female sexual behaviors

Process S

Our sleep drive. Peaks around 11 pm, decreases around 7 am. The greatest urge to sleep is the greatest difference between this and Process C

Hypothalamus (HPG)

Paraventricular nucleus & supraoptic nucleus directly releases hormones through the posterior pituitary portal: -oxytocin: also called the 'love hormone', which increases after pregnancy and accounts for the strong mother-child bond. Also increases during sex. -gonadotropin-releasing hormone: stimulates the anterior pituitary gland.

Ventral tegmental area

Part of mesotelencephalic system & mesocorticolimbic pathway. Axons of cell body project to limbic system: nucleus accumbens, olfactory tubercle, amygdala, and septum. It regulates pleasurable drug experiences. In the mesocortical pathway, dopamine is released to cortex areas, which influences our decisions to take the drug again. We think about the drug and crave it. This pathway starts here and ends in prefrontal cortex.

Suprachiasmatic nuclei (SCN)

Part of the medial hypothalamus, which has been shown to disrupt various circadian cycles, including sleep-wake cycles. It's our biological clock, and secondary clocks respond to this master clock. Light stimulates it, which results in decreased melatonin production by the pineal gland in the morning. Low light (darkness) leads to increased melatonin production, so this structure is not activated. The blue light from electronic devices can activate the SCN and make your body think it's day, which decreases melatonin production and delays sleep

Substantia nigra

Part of the mesotelenceaphalic dopamine system & nigrostriatal pathway. Releases dopamine into the dorsal striatum, which is part of the motor system. It increases behavioral activity associated w/ the drug. Ex: when cocaine is administered to rats, they keep rubbing their faces. May be responsible for habitual behaviors which explains why rats keep pressing the lever to get the drugs

Androgenic insensitivity syndrome

People are genetically male but phenotypically female. There's a mutation of androgen receptor gene, so androgen receptors are either unresponsive or absent. Testosterone is still produced b/c internalized testes have developed to secrete Mullerian-inhibiting substance (so no ovaries, fallopian tubes, or other female genitalia). But no receptors for testosterone to respond to, so a very short vagina will develop from other tissues (NOT Mullerian tissues). Higher risk of cancer b/c of internalized testes. People will normally take estrogen hormones

Physical dependence theory (addiction theory)

Physical dependence traps addicts in a vicious circle of drug taking and withdrawal symptoms. The idea was that drug users whose intake has reached a level sufficient to induce physical dependence are driven by their withdrawal symptoms to self-administer the drug each time they attempt to curtail their intake. It's for negative reinforcement. But theory doesn't tell you why people start taking the drug

Birth control pills

Prevents pregnancy by interfering w/ feedback cycle between ovaries and pituitary. Most effective is combination pill which contains estrogen and progesterone. The pill delivers high levels of estrogen just after end of menstrual period, which suppresses release of FSH so no development of Graafian follicle. Next the combo pill delivers high levels of progesterone which blocks secretions of LH. When progesterone's released early it tricks the body into thinking its menstrual cycle is farther along than it really is. If LH (or FSH) fails to be suppressed, then FSH (or LH) will act as a backup system to prevent pregnancy

Alpha fetoprotein

Produced by placenta and liver cells during fetal development. It binds to circulating estradiol and prevents its entry into brain. But testosterone is immune to this, so it can travel from the testes to the brain cells where it's converted to estradiol. It's not broken down in the brain b/c this protein can't readily penetrate the blood-brain barrier. This leads to masculinization of the brain. Both males and females go through masculinization process

THC

Produces psychoactive effects in marijuana. Has therapeutic effects: can suppress nausea and vomiting in cancer patients and stimulates appetite of AIDS patients. Also blocks seizures, dilates bronchioles of asthmatics, decreases glaucoma, reduces anxiety, some kinds of pain, and symptoms of multiple sclerosis

Brain mechanisms (biological clock-time, hunger & satiety signals)

Prolonged wakefulness and metabolic activity of neurons in the brain leads to accumulation of adenosine, which activates the vlPOA (SWS-on region) to release more GABA. This inhibits the arousal system (waking-on region). But adenosine decreases during the night b/c less activity vs. day, so excitatory effect decreases & less GABA produced. Our suprachiasmatic nucleus and hunger signals can excite LH orexin, which then activates arousal system. Satiety signals can inhibit LH orexin, which deactivates arousal system

Conditioned place-preference paradigm

Rats repeatedly receive a drug in one compartment (the drug compartment or control compartment) of a two-compartment box. During the test phase, the drug-free rat is placed in the box, and the proportion of time it spends in the drug compartment vs. control compartment is measured. Rats usually prefer the drug vs. control compartment when the drug compartment has been associated w/ the effects of addictive drugs in humans. The main advantage of this paradigm is that subjects are tested while they're drug-free, which means that the measure of the incentive value of a drug isn't confounded by other effects the drug might have on behavior

Intracranial self-stimulation (ICSS)

Rats, humans, and many other species will administer brief bursts of weak electrical stimulation to specific sites in their own brains. Brain sites capable of medicating the phenomenon are often called pleasure centers. This was a starting point for the study of neural mechanisms of addiction and the positive & negative reinforcements of it. Early studies involved stimulation of septal or lateral hypothalamus b/c rates of self-stimulation from these sites were very high. According to Olds & Milner, specific brain sites that mediate self-stimulation are those that normally mediate the pleasurable effects of natural rewards.

Electrooculogram (EOG, physiological measure of arousal & sleep)

Records eye movements. It's based on the fact that there's a steady potential difference between the front (positive) & back (negative) of the eyeball. B/c of steady potential, when eye moves, a change in the electrical potential between electrodes placed around the eye can be recorded. Can measure horizontal and vertical eye movements. Can measure SWS or slow wave sleep and REM or rapid eye movements

Anterior pituitary (HPG)

Releases gonadotropin hormones: -follicle-stimulating hormone (FSH): stimulates sperm & egg development -luteinizing hormone (LH): stimulates ovulation, so it spikes once a month in women. Males also have this hormone but we're not sure what it does

Functional tolerance

Response to drug is decreased by cellular mechanisms within neurons, like receptor changes. Ex: -GABA binding easier when alcohol is consumed. More GABA binding = more receptor changes -drug agonists leads to receptor down-regulation: less receptor expression, so greater alcohol tolerance = less depressant effects, so you drink more -drug antagonists may lead to receptor up-regulation: not enough receptor stimulation

Elimination theory (recuperation theory of sleep)

Rids the body & brain of excess sensory info. Your brain & body is constantly stimulated, so pruning occurs in CNS. If sensory info is important, it'll be incorporated into long term memory. If not important (i.e., what you had for breakfast), it'll be forgotten. Certain synaptic connections are strengthened and weakened during sleep

Narcolepsy cause

Seems to be caused by deficiency of orexin in humans. In canines, there's a mutation in orexin B receptor. When emotional stimuli activates the amygdala, people can experience aspects of REM sleep b/c of this orexin deficiency. In humans, complete absence of orexin in 7/9 people w/ narcolepsy. Most people are born w/ orexin, but during adolescence the immune system attacks these neurons so symptoms begin (autoimmune disease). Could be caused by environmental factors like toxins or allergies

Anne S

She had Androgenic Insensitivity Syndrome. She was chromosomally male (XY), had internalized testes but no ovaries, and had hormone levels of a man.

Lesion studies

Shows that 6-hydroxydopamine (6-HD) chemical lesions disrupts ICSS. Only dopamine neurons take up this chemical. Rats don't press the lever anymore b/c dopamine neurons killed off. It causes brain damage

Antagonist studies

Shows that dopamine antagonists decreases ICSS, so no lever pressing. Once drug wears off, lever-pressing continues

Immobilization theory (adaptation theory of sleep)

Sleep is an innate response w/ species specific patterns. It's a period of safety for humans and animals. Keeps us inactive and safe in least efficient part of light cycle. We can't see well at night, so sleep can promote safety and reproductivity. Same applies to nocturnal animals whose predators are present during the day. Gene is passed onto offspring

Adaptation theories of sleep

Sleep is not a reaction to the disruptive effects of being awake but the result of an internal 24-hour timing mechanism, that is, we humans are programmed to sleep at night regardless of what happens to us during the day. We have evolved to sleep at night b/c sleep protects us from accidents and predation during the night -immobilization theory -energy conservation theory

Estrus

Surges of progesterone, a period of 12-18 hrs during which the female is fertile, receptive, proceptive, and sexually attractive

Hypothalamic-Pituitary-Gonadal Axis (HPG)

Starts in the hypothalamus, which secretes gonadotropin-releasing hormones to stimulate the anterior pituitary gland, which releases gonadotropin hormones (LH & FSH) to stimulate the gonads. The gonads produce androgens, estrogens, and gestagens

Positive incentive theory (addiction theory)

The primary factor in most cases of addiction is the craving for the expected pleasure-producing properties of the drug (the positive incentive). Theory explains why people repeatedly take the drug b/c it produces pleasure which leads to physiological dependence. But positive incentives fail, so people become tolerant and don't get high anymore

Amphetamine (stimulant)

Taken orally. It's considered an empathogen b/c it produces feelings of empathy & increased sensitivity. Synthetic stimulants, also called speed, uppers, bennies, meth, and dexies. Used in high doses for euphoric rush. People who have been on extended highs sometimes crash and fall into a deep sleep or depression. Some people commit suicide, and high doses can cause restlessness, irritability, hallucinations, paranoid delusions, loss of appetite and insomnia. Hallucinations & delusions can mimic paranoid schizophrenia (psychosis).

Incentive sensitization theory (addiction theory)

The central tenet of this theory is that the positive-incentive value of addictive drugs increases (is sensitized) w/ drug use. In addiction-prone individuals, drug use sensitizes the drug's positive-incentive value, thus rendering the individuals highly motivated to seek and consume the drug. It isn't the pleasure of taking the drug that's the basis of addiction, but the anticipated pleasure (wanting) of drug taking. Before sensitization, wanting/craving & liking/pleasure are at a high. But after sensitization, wanting/craving increases while liking/pleasure decreases b/c of tolerance

Nicotine

The major psychoactive ingredient of tobacco. It acts on nicotinic cholinergic receptors in the brain. Nonsmokers respond to cigarettes w/ nausea, vomiting, coughing, sweating, abdominal cramps, dizziness, flushing, and diarrhea. Smokers are more relaxed, alert, and less hungry. Withdrawal effects: depression, anxiety, restlessness, irritability, constipation, and difficulties sleeping & concentrating

REM sleep

The stage of sleep characterized by rapid eye movements, loss of core muscle tone, and emergent stage 1 EEG. This is the dream stage of sleep. When you wake up in the middle of the night, you're coming out of this stage b/c cortex is already aroused -promotes brain development & neuroplasticity or brain connections -facilitates learning -consolidation of nondeclarative memory or physical tasks that can be learned, also called perceptual memory -REM rebound phenomenon

Electromyogram (EMG, physiological measure of arousal and sleep)

The usual procedure for measuring muscle tension. It's usually recorded between 2 electrodes taped to skin over muscle of interest. An increase in muscle contraction is an increase in the amplitude of the raw signal, which reflects the number of muscle fibers contracting at any one time. Measures changes in muscle tension by placing electrodes on the facial and neck muscles (i.e., mentalis muscle) to detect atonia or loss of muscle tone, which reduces during REM sleep. So we can't move in REM sleep or act out dreams

Satiety signals

These have an inhibitory effect on LH orexinergic neurons, which then deactivates our arousal systems and promotes the vlPOA to release more GABA, thereby making us fall asleep. These signals occur after we've eaten and become full. B/c it decreases orexin and stimulates GABA, we become more sluggish and lazy. Once we digest, we're more awake. Inhibitory effect on orexin

Hunger signals

These increase the more we fast, and this begins about 3-4 hours after we have fallen asleep. These signals can arouse LH orexinergic neurons, which then stimulates our arousal system to wake us up. Excitatory effect on orexin

Opiates

They exert their effects by binding to receptors whose normal function is to bind to endogenous opiates, which bind to receptors of 2 classes: endorphins and enkephalins. Addicts experience a euphoric rush. Withdrawal: increase in restlessness, watering eyes, runny nose, yawning, sweating, fitful sleep, chills, shivering, profuse sweating, gooseflesh, nausea, vomiting, diarrhea, cramps, dilated pupils, tremor, muscle pains & spasms. Many flu-like symptoms! Symptoms most severe by 2nd or 3rd day, then disappears by 7th day. Risks of constipation, pupil constriction, menstrual irregularity, and reduced libido, but very minor health hazards.

Shepard Siegel's results

Those in the control group overdosed immediately, while those in the different-test group had 2nd highest rates of overdose. Same-tested group had lowest rates of overdose b/c of developed tolerance. If only testing physical tolerance (functional or metabolic) then all groups show same results. But this is testing conditioned tolerance!

Sleep/waking: flip-flop is on

When the sleep-promoting region in the vlPOA is inhibited, less GABA is released to the brain stem and forebrain arousal systems. These arousal systems are activated, so more neurotransmitters (acetylcholine, norepinephrine, serotonin, and histamine) are released, resulting in the alert waking state

Marijuana

Usual mode of consumption is to smoke the leaves of Cannabis sativa through a joint or a pipe. Very effective when ingested orally, and if baked into an oil-rich substrate (brownies) it can promote absorption from the gastrointestinal tract. Psychoactive effects due to THC. Classified as a narcotic. High doses impair psychological functioning, short-term memory, and ability to carry out tasks involving multiple steps. Speech slurs, meaningful conversation is difficult. Sense of unreality, emotional intensification, sensory distortion, feelings of paranoia, and motor impairment also present. Addiction is low. Withdrawal (very rare): nausea, diarrhea, sweating, chills, tremors, sleep disturbances. Produces respiratory problems like coughing, bronchitis, and asthma. Also tachycardia or elevated heart rate

Sleep/waking: flip-flop is off

When the sleep-promoting region in the vlPOA is activated, more GABA is released to the brain stem and forebrain arousal systems. These arousal systems are inhibited, so less acetylcholine, norepinephrine, histamine, and serotonin are released. They all bottom out during REM sleep, resulting in slow-wave sleep

Teratogen

What nicotine is, which can disturb the normal development of the fetus. Smoking during pregnancy increases miscarriage, stillbirth, and early death of child. Alcohol is also this b/c it can cause fetal alcohol syndrome

Genital activity (brain mechanisms)

When sub-lateral dorsal nucleus is stimulated (REM sleep), it activates ACh neurons in the pons, which then activates the lateral preoptic area and leads to sexual arousal during REM

Movements (brain mechanisms)

When sub-lateral dorsal nucleus is stimulated (REM sleep), it activates inhibitory interneurons found in the spinal cord. They inhibit motor neurons, leading to atonia or loss of muscle tone. This is why we can't move or act out our dreams during REM

Cortical arousal & REM (brain mechanisms)

When sub-lateral dorsal nucleus is stimulated (REM sleep), it activates the medial pontine reticular formation, which activates ACh neurons in forebrain & pons, which leads to frontal cortex arousal. This is correlated w/ formation of dreams and activation of random memories during REM. ACh neurons can also stimulate the tectum, which contains the superior colliculus (visual function). This is responsible for the actual rapid eye movements in REM

Brain mechanisms (REM sleep flip-flop)

When the vlPOA is activated to release GABA, it can deactivate LH orexinergic neurons and the ventrolateral periaqueductal grey (REM-off). We go into REM sleep, which activates our sub-lateral dorsal nucleus. Another way to activate REM sleep is emotional stimuli activating the amygdala (excitatory effect on SLD), which then activates our sub-lateral dorsal nucleus to go into REM sleep.

Sex chromosomes

X and Y chromosomes -XX = female -XY = male

Testicular disorder (SRY gene mutation)

XX chromosome, but phenotype is male. Random mutation during formation of sperm cell that leads to translocation. SRY gene is misplaced onto X chromosome. Male external genitalia is smaller, may be ambiguous (intersex). If phenotype is more masculine, raised as males and given testosterone treatment. Reported to have typical male identity

Swyer syndrome (SRY gene mutation)

XY genotype, but the phenotype is female. SRY gene mutations prevent production of sex-determining region of Y protein or results in production of a nonfunctioning protein. Fetus develops into female, has external genitalia, uterus, fallopian tubes, etc. But no functioning ovaries (gonads), so unable to have kids. Normally discovered in puberty, so given hormonal therapy through estrogen supplements. Raised as female and reported to have typical female identity

Stages of sleep EEG

You spend less time in SWS and descend quickly into REM as you sleep through night -awake: beta & alpha waves -non-REM stage 1: theta waves, low-voltage high frequency signal that is similar to, but slower than, that of alert wakefulness -non-REM stage 2: theta, sleep spindles, & k complexes, slightly higher amplitude and lower frequency -non-REM stage 3 (stages 3 & 4) or slow wave sleep: delta waves, decrease of muscle tone. In stage 3 you can move, sleep talk/walk. Imagery happens, but it's short and abrupt, not like dreams in REM. You can have nightmares like falling off cliff and startling awake. They're strong, short emotional bursts. Stage 4 is a deeper sleep, so less likely to talk and move