Bio Psych Exam 4
circumventricular organs
have fenestrated capillaries—lack the usual blood-brain barrier, allowing neurons in these regions to monitor salt concentration and hormones in the bloodstream.
Phagocytes
immune system cell that engulfs invading molecules or microbes
explain why sleeping pills are unsatisfactory
none of these substances provide a completely normal night of sleep in terms of time spent in various sleep states, such as REM, and none of them remain effective when used repeatedly
what responds to changes in osmotic pressure?
Osmosensory neurons in the hypothalamus and circumventricular organs
depression treatment
MAO inhibitors, tricyclics, SSRI's (prozac), SNRI's (effexor, cymbalta, pristiq)
A benefit of restricted food intake may be longevity
May be related to the decrease in basal metabolism; perhaps due to transcription factors that control trophic factors that promote cell growth.
Redundancy in thermoregulatory control systems in the nervous system
Neurons of the preoptic area (POA) integrate sensory inputs and drive physiological thermoregulatory responses. Multiple other brain regions also appear to contribute to thermoregulation.
When did the odor that was presented during learning cause the highest retrieval performance?
Odor during SWS Studies using mutant mice suggest that synapses are strengthened when awake and then consolidated during sleep by a global scaling back of other synapses
set point
The point at which your "weight thermostat" is supposedly set. When your body falls below this weight, increased hunger and a lowered metabolic rate may combine to restore the lost weight
if food deprivation is prolonged
gluconeogenesis converts fat and proteins to glucose and ketones, a form of fuel.
heritability of schizophrenia
grandpa vs cousin vs sibling
How can certain beetles and fishes withstand under 0 degrees Celsius?
these animals produce an "antifreeze" protein in body fluids that prevents ice crystals from forming in their cell membranes
sea birds
some have specialized salt glands near the nostrils that can excrete highly concentrated salt solutions so they can drink seawater - excess salt is pulled out of the plasma and released out of the nostrils
behavioral regulation
• Change exposure of body surface • Change external insulation • Change surroundings (sun, shade, etc.)
Sleep aids memory consolidation
• Sleep improves declarative memory (FACTS) • Sleep deprivation increases likelihood of creating false memories. • REM sleep may help consolidate nondeclarative memory (experiences, emotion) • New dendritic spines in mice increased and were stronger after sleep, and decreased if they were sleep-deprived
angiotensin cascade
*Angiotensinogen (in blood)* Enzyme: Renin (from kidneys) *Angiotensin I* Enzyme: Converting enzyme *Angiotensin II* Enzyme: Aminopeptidase *Angiotensin III*
glycogenesis
(converting glucose to glycogen) is regulated by the pancreatic hormone insulin
Glycogenolysis
(converting glycogen to glucose) is controlled by glucagon
why did sleep evolve?
- Most growth hormone is released during SWS. - sleep helps us resist illness - glia flush waste products faster than when awake - Sleep aids memory consolidation - sleep restores the body and brain by replenishing metabolic requirements, such as proteins - Sleep enforces niche adaptation. - Sleep helps animals avoid predators
what are the advantages of endotherms?
- can maintain body temperature even if the temperature of the surrounding environment changes - can occupy habitats with a wide range of ambient temperatures - enhanced capacity for oxygen utilization which helps to sustain high levels of muscular activity for much longer periods of time (endothermic hares vs ectothermic tortises)
review the possible nuerochemical bases of schizophrenia and discuss several classes of antipsychotic drugs and their mechanisms of action
- chlorpromazine alleviates positive symptoms of schizophrenia that kept people in mental institutions by blocking dopamine d2 receptors - high doses of amphetamine produce similar symptoms of schizophrenia - amphetamine psychosis - PCP produces phenomena strongly resembling symptoms of schizophrenia and acts as NMDA receptor antagonist, preventing glutamate from having its usual effects
aspects of emotion
- feelings - actions - physiological arousal - motivation
What are the four functions often ascribed with sleep?
- memory consolidation - energy conservation - niche adaptation - body restoration
ventricular enlargement
- predicts later development of schizophrenia in adolescents - enlarged lateral ventricles - hippocampus and amygdala is smaller in ill patient - causes ventricular enlargement
salt homeostasis
- the amount of salt retained is determined primarily by the amount of salt contained in the extracellular fluid - humans can't get rid of salt in saltwater fast enough
the role of insulin in energy utilization
- the brain requires a constant supply of glucose for energy without the aid of insulin - the body needs insulin to use glucose, so in the absence of insulin, the body must use fatty acids for energy - insulin mediates the conversion of glucose to glycogen
4 major neural systems
1. forebrain 2. brainstem 3. pontine 4. hypothalamic
negative feedback
A mechanism of response in which a stimulus initiates reactions that reduce the stimulus
review the evidence for a core set of emotions
Darwin presented evidence that certain expressions of emotions are universal among people of all regions of the world. Emotional expression may have originated from a common ancestor - apparent emotional expressions of various mammals and physiological mechanisms of emotional display (facial muscles). Beyond primates - tickling and playing with rats elicits vocalizations that resemble laughter
positive feedback
Feedback that tends to magnify a process or increase its output.
Vasopressin (antidiuretic hormone, ADH)
Hypovolemia causes release of this hormone from the posterior pituitary gland which induces blood vessel constriction and reduces water flow to the bladder
alpha rhythm
a brain potential of 8-12 Hz that occurs during relaxed wakefulness
vertex spikes
a sharp-wave EEG pattern that is seen during stage 1 sleep; the beginning of NREM
aldosterone
a steroid hormone, is released from the adrenal gland in response to thirst signals. It stimulates the kidneys to conserve Na+, aiding water retention. sodium follows water!
describe experiments that established the existence of a circadian clock in the hypothalamus
a tiny subregion of the hypothalamus - the sprachiasmatic nucleus (SCN) - serves as a biological clock. Lesions here interfered with circadian rhythms of drinking and locomotor behavior. Mutation tau affects the endogenous clock. Response to an SCN transplant with 2 tau mutations was a free-running activity rhythm of 19.5 hours, matching the SCN of the donor animal. Transplant showed that the period of the clock is determined within the SCN. Always that behavior of the donor SCN & NOT the recipient.
stage 1 sleep
accompanied by slowing of heart rate and a reduction of muscle tension; usually lasts several minutes
Anorexigenic neurons of the paraventricular nucleus (PVN)
act to decrease appetite and feeding
brainstem system
activates forebrain into wakefulness
hypothalamic system
affects other three brain systems to determine which state the brain will be in
discuss the pros and cons of trying to measure emotional states using techniques like polygraph testing
all negative emotions involve the same physiological responses: heart rate, blood pressure, sweating (liars vs anxious innocents)
hypothalamic neurons
also monitor cytokines
endocannabinoid system
also regulates appetite and feeding, primarily stimulating hunger. antagonists effectively suppress appetite, but cause depression
forebrain system
can display SWS by itself
general anaesthetics
cause unconsciousness, produce slow waves in EEG that resemble SWS. Almost all are agonists of GABAA receptors.
angiotensin II
conserves water by constricting blood vessels, increasing blood pressure, and triggering release of vasopressin and aldosterone
metabolic adaptation
decrease in basal metabolism following weight loss. Get basal metabolic rate up by exercising on a diet.
stage 3 sleep (slow wave sleep)
defined by appearance of large amplitude, very slow waves called delta waves
stage 2 sleep
defined by waves of 12-14 Hz called sleep spindles, which occur in periodic bursts, and K-complexes (sharp negative EEG potential)
B lymphocytes
formed in the bone marrow that mediates humoral immunity and produce antibodies
T lymphocytes
formed in the thymus, include killer T cells, which attack foreign microbes and, helper T cells, which secrete cytokines
beta activity
fully awake person; mixture of frequencies dominated by waves of relatively fast frequencies and low amplitude, greater than 15-20 Hz
ghrelin
is produced in the stomach and is an appetite stimulant. Levels rise during fasting and fall after a meal, except in obese subjects where ghrelin levels remain high
Hypovolemic thirst
is stimulated by low extracellular fluid volume. Triggered by loss of water, e.g., through blood loss(hemorrhage) diarrhea, vomiting, etc. Baroreceptors in major blood vessels and the heart detect the initial drop.
basic emotions - medium level of intensity
know opposites
peripheral peptide hormones
leptin, ghrelin, PYY3-36. and glucagon-likepeptide-1 (GLP-1)
Ventromedial hypothalamus (VMH)
lesions cause animals to eat to excess (hyperphagia) and become obese; suggests VMH is a satiety center
Lateral hypothalamus (LH)
lesions cause aphagia (cessation of eating); suggests LH is a hunger center
as you age
less REM sleep and more wakefulness
bipolar treatment
lithium
isolated brain
made by an incision between the medulla and the spinal cord. - Body is paralyzed but brain is still alive. - electrical activity in the forebrain showed constant SWS but not REM. - The constant SWS activity in the forebrain is generated by the basal forebrain
allostasis
many physiological systems shift responses, depending on the nature of the stressors and prior experience, e.g.,heart rate and blood pressure are continually shifted to accommodate current or anticipated activity levels
arcuate nucleus
of the hypothalamus contains an appetite controller governed by several hormones, like insulin
Orexigenic neurons
of the lateral hypothalamus (LH) act to increase appetite and food intake
basal metabolism
processes of heat production, maintenance of membrane potentials, and all other basic life-sustaining processes. At the start of a diet (less nutrition), the basal metabolic rate will fall to prevent losing weight
leptin
produced by fat cells
glutamate hypothesis
proposed that schizophrenia results from an underactivation of glutamate receptors
electroencephalography (EEG)
recording the electrical activity of the brain via electrodes on the scalp
osmotic thirst
stimulated by high extracellular solute concentration. Water is pulled out of the cells when extracellular salt concentration is too high. Loss of intracellular fluid.
redundancy
the body has multiple systems for regulating the internal environment; allows for compensation if one monitoring system fails.
ANP
the heart decreases secretion of atrial natriuretic peptide (ANP). In the absence of ANP, blood pressure increases, and water excretion decreases.
pontine system
triggers REM sleep
anxiolytics
used to combat anxiety (alcohol, barbiturates, opiates, and benzos)