Psyc 351D exam #4
Pavlovian conditioning:
*Classical conditioning* Dogs learned to associate a tone (stimulus) with food, and salivated Today, either eye-blink conditioning or fear conditioning are used (each have discrete brain circuits)
In a pharmacological intervention, patient takes a drug to influence plasticity:
*NGF* If NGF given to animals with strokes, motor functions improve Correlated with increase in dendritic branching & spine density in the remaining motor regions Correlated with improved motor function
Musicians, Braille & cortical representations:
*Right-handed musicians who play stringed instruments show an increased cortical representation of the fingers of the left hand* Braille readers have an increased cortical representation of the reading finger
Explicit memory areas in brain: (7)
1. Medial temporal 2. Frontal lobe 3. Hippocampus 4. Amygdala 5. Entorhinal cortex 6. Parahippocampal cortex 7. Perirhinal cortex (*HAPPE MoFo*)
ACh, 5-HT and NE specifically synapse on 4 brain areas:
1. Neocortex 2. Temporal 3. Medial thalamus 4. Prefrontal
The adult primate brain can generate neurons destined for 3 areas:
1. Olfactory bulb 2. Hippocampal formation 3. Neocortex of frontal & temporal
2 types of neurons in hypo:
1. Senses glucose levels 2. Senses lipid levels
Unidirectional, unconscious flow for memory: (4)
1. Sensory & motor info to the neocortex 2. Neocortex to basal ganglia (which also receives DA from substantia nigra) 3. BG to ventral thalamus 4. Ventral thalamus to premotor
Reciprocal circuit for explicit memory: (5)
1. Sensory & motor info to the neocortex 2. Neocortex to the temporal 3. Temporal to the prefrontal, medial thalamus & back to neocortex 4. Prefrontal to medial thalamus & back to temporal 5. Medial thalamus to the temporal & back to the prefrontal
The neocortex & EC connections have 2 benefits:
1. Signals from the medial temporal region back to sensory regions keep the sensory experience alive (outlasts the actual experience) 2. Pathway back to neocortex means that it is kept apprised of info being processed in the medial temporal region
Hypothalamic cells around the _____ detect _____ thirst
3rd ventricle Osmotic
A study that examined resting state fMRI in smokers found that: A) there was greater connectivity in the reward systems in smokers. B) there was decreased connectivity in the systems regulating decision making in smokers. C) there was decreased connectivity in the systems regulating impulse control in smokers. D) All of the answers are correct.
A
A/an ______ leads to an increase in the number of dendritic spines, and a/an ______ leads to a decrease in dendritic spines. a. increase in estrogen; decrease in estrogen b. increase in testosterone; decrease in testosterone c. decrease in estrogen; increase in estrogen d. decrease in testosterone; increase in testosterone
A
Bars and pubs that offer their customers very salty free popcorn are hoping to capitalize on: A) osmotic thirst. B) hypovolemic thirst. C) the fact that students will never turn down free food. D) dehydration.
A
Brain imaging research has shown that activity in the ______ is reduced in individuals with dyslexia. A) left temporoparietal cortex B) left occipital cortex C) right frontal cortex D) right temporoparietal cortex
A
Damage of the lateral temporal cortex, insula, & medial frontal cortex occurs in _____________ and suggests that the insula is implicated in _________________. A) Herpes Simplex Encephalitis; retrograde amnesia B) Alzheimer's Disease; transient global amnesia C) Huntington's Disease; dissociative amnesia D) Korsakoff's Syndrome; anterograde amnesia E) none of the above
A
During LTP_____ enters postsynaptic NMDA receptors to begin a chain of events that lead to an increase in the number of postsynaptic AMPA receptors. a. Ca2+ b. Cl- c. Na+ d. K+
A
Emotional memory uses ______________ processing A) both top-down and bottom-up B) neither top-down or bottom-up C) none of the above D) bottom-up E) top-down
A
Explicit memory is to implicit memory as: A) conscious is to unconscious B) reference is to working C) semantic to episodic D) skill to fact
A
Eye-blink conditioning involves neural circuits in the: A) cerebellum. B) amygdala. C) orbital frontal cortex. D) occipital lobe.
A
Eye-blink conditioning is an example of: A) respondent conditioning. B) instrumental conditioning. C) operant conditioning. D) fear conditioning.
A
High estrogen levels in female rats: A) increase the number of dendritic spines on hippocampal pyramidal cells. B) decrease the number of dendritic spines on hippocampal pyramidal cells. C) peak every eight days. D) increase the number of axons of hippocampal pyramidal cells.
A
In androgen insensitivity syndrome: A) a genetic male develops a female phenotype. B) a genetic female develops a male phenotype. C) males fail to undergo puberty. D) females fail to undergo puberty.
A
In males, the medial preoptic area controls _____, whereas the amygdala controls _____. A) mating; sexual motivation B) sexual motivation; mating C) mating; lordosis D) lordosis; sexual motivation
A
It has been argued that emotional memory involves which of the following structures? a. amygdala b. thalamus c. hypothalamus d. thalamus and hypothalamus
A
Last year, every time John watched a football game at his friend's house, he drank beer. Now, whenever John watches a football game, he finds himself craving beer. This is an example of: A) Pavlovian (classical) conditioning. B) operant conditioning. C) fear conditioning. D) the successful use of beer commercials during football games.
A
Research by Scheibel and colleagues found that dendritic branching increased in _____ in people with high levels of education. A) Wernicke's area B) Broca's area C) the hippocampus D) the motor cortex
A
Sherry and colleagues have found that birds that cache food for the winter: A) have a hippocampol formation that is more then twice as large as one would expect B) have a smaller hippocampal formations that those of birds C) same size D) ten times
A
Taste-aversion learning can be abolished by lesions to the: A) amygdala. B) dorsolateral prefrontal cortex. C) inferior frontal cortex. D) orbital frontal cortex.
A
The more the temporal lobe is damaged, A) the further back in time the amnesia will extend B) the less memories will be consolidated C) none of the above D) the further forward in time the amnesia will extend E) the more memories will be consolidated
A
The phenomenon of phantom limb after amputation can most easily be explained by: a. encroachment of the denervated cortex area by some other part of the body. Thus when that part of the body is stimulated, the brain is tricked into thinking that the limb still exists. b. degeneration of the cortical area representing the lost limb. c. stimulation of the nerve endings of the stump. d. collateral stimulation of the thalamus.
A
Which of the following was largely unaffected after the memory patient HM's surgery? a. implicit memory b. verbal memory c. explicit memory d. visuospatial memory
A
Glutamate acts on ____ & ____ receptors
AMPA NMDA
Procedural memory:
Ability to perform a task
Medial forebrain bundle:
Activates fibres forming the ascending pathways from DA-producing cells of the tegmentum
The hormonal effects on the adult brain are activating/organizing effects
Activating
Emotional memory:
Affective properties of stimuli or events Seems to be both implicit and explicit
Focal hand dystonia:
Afflicts those who practice trying to make perfect finger movements Those at high risk are string players (vibration of strings) *Synchronous activation* of digits may lead to unwanted side effects Researchers used MEG, found that finger areas overlapped one another After special training, the subjects showed marked alleviation of symptoms; *normalization of cortical map*
Korsakoff's syndrome occurs due to a thiamine (Vitamin B1) deficiency, which ultimately damages the A) none of the above B) medial thalamus and mammilary bodies of the hypothalamus C) ventrolateral thalamus and prefrontal cortex D) hippocampus and the perforant pathway E) hippocampus and the fornix fimbria pathway
B
Masculinization of the brain is most directly caused by: A) testosterone. B) estradiol. C) progesterone. D) androgens.
B
Mishkin and his colleagues have hypothesized that the __________ are central to implicit memory A) basal B) frontal C) hippocampus D) medial
B
Prolonged exposure to the hormones called glucocorticoids: a. increases dendritic branching in the hippocampus. b. kills cells in the hippocampus. c. decreases glial numbers. d. increases spatial memory.
B
Research by Scheibel and colleagues found that dendritic brancing increased in _______ in people with higher levels of education A) motor cortex B) Wernicke's C) hippocampus D) Broca's
B
The effects that hormones have on the adult brain are referred to as: A) organizing effects. B) activating effects. C) endocrine effects. D) hormonal effects.
B
The temporal lobes are critical for ________and the frontal lobes are important for ___________. A) short term, long term B) long term, short term C) implicit, explicit D) verbal, visual
B
When animals engage in activities such as eating and sexual activity, there is a marked increase in dopamine levels in the: A) amygdala. B) nucleus accumbens. C) caudate nucleus. D) hypothalamus.
B
Which of the following areas is most likely involved in visualization memory? A) limbic B) parahippocampal C) perirhinal D) basal ganglia
B
Which of the following is *not* a part of neural circuit for emotional memories? A) hypothalamus B) cerebellum C) amygdala D) basal ganglia
B
Which of the following neurotransmitters is the most likely source of reward in brain self-stimulation experiments? A) serotonin B) dopamine C) acetylcholine D) noradrenaline
B
Which of the following statements about sexual orientation and brain organization is *not true*? A) The preoptic area of the hypothalamus of the male human has up to twice as many neurons as in female humans. B) The preoptic area of the hypothalamus of heterosexual males is larger than the preoptic area of homosexual males. C) The suprachiasmatic nucleus is twice as large in homosexual males as in heterosexual males. D) The nucleus called INAH3 is twice as large in the heterosexual brain as in the homosexual brain.
B
Which of the following structures play an important role in short-term memory or temporary memory? a. temporal lobes b. frontal lobes c. occipital lobes d. parietal lobes
B
Which of the following terms can be used instead of explicit memory? a. skill b. conscious memory c. unconscious memory d. habit memory
B
_____ is a change in the ability to recall or recognize previous experience. A) Learning B) Memory C) Reasoning D) All of the answers are correct
B
______ is a change in an organism's behavior as a result of experience. a. All of the answers are correct. b. Learning c. Memory d. Cognition
B
Cells in the brain produce _____, which converts testosterone into estradiol (an estrogen)
Aromatase
Adaptive synapses in the brain participate in _____, a response elicited by linking unrelated stimuli together
Associative learning
Changes in dendrite morphology: A) imply new circuitry B) imply addition or subtraction C) occur spontaneously
B
Damage to the lateral hypothalamus causes: A) obesity in animals. B) animals to stop eating. C) anorexia nervosa. D) overeating in animals.
B
Drinking water as a result of an increase in concentrations of chemicals is: A) hypovolemic thirst. B) osmotic thirst. C) regulated by the thalamus. D) regulated by the amygdala.
B
Explicit memory relies mainly on ______ processes, and implicit memory relies mainly on ______ processes. a. automatic; voluntary b. top-down; bottom-up c. bottom-up; top-down d. reflexive; cognitive
B
If a monkey has to remember the position of a light for a delay period after the light goes out, neurons in the __________ fire to help the monkey retain a memory trace. a. hippocampus b. prefrontal cortex c. amygdala d. occipital cortex
B
In animal models, the administration of nerve growth factor (NGF) following a stroke has been shown to: a. decrease tissue inflammation. b. stimulate dendritic growth. c. have no effects on recovery. d. increase the number of new neurons.
B
_____ increases when animals solve specific problems & may enhance plastic changes
BDNF
Enriched environments in adult rats have been shown to increase: a. brain weight. b. number of synapses. c. number of blood capillaries. d. All of the answers are correct.
D
Neurofibrillary tangles:
Paired helical filaments found in both cerebral cortex & hippocampus
Damage to the _____ nucleus also produces hyperphagia
Paraventricular
The *parahippocampal* cortex receives most input from the ____ cortex for ____ memory
Parietal Visuospatial
When comparing cells in the trunk area, in the finger area, and in the supramarginal gyrus (higher cognitive processes), they found individual differences (experience-dependent change):
People who had a high level of finger dexterity had larger differences in the trunk & finger neurons Career word processors, not sales reps
Periaqueductal gray matter:
Perception of pain
Monkeys with _____ lesions cannot do the visual-recognition task
Perirhinal
The cognitive aspect of feeding includes ____ (or its absence)
Pleasure
Positive VS Negative reinforcement:
Positive = stimulus added Negative = stimulus removed *Both increase behaviour*
Taxi drivers in London also have a larger _______
Posterior hippocampus
Organizing effects mostly occur in the ____ of the lateral/medial hypothalamus
Preoptic Medial
Some patients with _____ amnesia show a massive reduction in brain activity in frontal regions
Psychogenic
To measure *implicit* motor-skills learning, a person is taught a skill (_____ task)
Pursuit-rotor
Animals engage in a wide range of voluntary behaviours because the behaviours are _____
Rewarding
When the body is stressed, the adrenal cortex produces _____
Glucocorticoids
Language is implicit/explicit
Implicit
Episodic memory:
Includes not only a record of events that took place but also a record of our presence & role in the events Our personal experiences form the basis of who we are & the rules by which we live
fMRI studies have shown a bilateral decrease/increase in activity in the hypothalamus when men view erotic video clips
Increase
Changes in sensitized animals:
Increased # of receptors at synapses and of more synapses Increase in dendritic growth & spine density in rats that were sensitized to amphetamine, cocaine or nicotine Affected the *nucleus accumbens* Also in the *prefrontal* cortex; both these areas receive DA projections
Damage to the hypo mostly effects _____ levels in the blood
Insulin
EC receives many projections, so it likely ____
Integrates
One study trained male rats to press a bar to deliver receptive females:
Lesions were then made in their medial preoptic areas They would still press the bar to obtain females, but they would no longer mate with them So the medial preoptic area controls mating, but does not control sexual motivation
Object-position task:
Monkey is shown 1 object to be displaced for a food reward & then is shown the same object with a 2nd identical one, and must displace object in the *same position*
High estrogen:
More dendritic spines & more synapses in hippocampal pyramidal neurons
Marijuana, morphine & some antidepressants change dendritic length & spine density:
Morphine produces a *decrease* in dendritic length & spine density in nucleus accumbens & prefrontal
A key to weight gain in the developed world is evolutionary:
Most of our food was only available seasonally in the past In a world with uncertain food availability, it makes sense to stores excess body calories in the form of fat to be used when food is scarce Historically, plumpness was a standard of beauty
What is likely the cause of dyslexia?
Much more common in *boys*, so research in the 80s reasoned that it much be hormonal influences in early development that influence brain development too Examined postmortem brains Found abnormal collections of neurons, or "*warts*", in & around the *language areas* of the brain Also found abnormalities in the *auditory thalamus*
Also, animals quickly learn to press a bar to obtain an injection of _____ directly into the midbrain tegmentum or the nucleus accumbens
Opiates
Delayed-alternation task:
The monkey is shown 2 lights in the choice test & must choose the light that is *not in the same location* as the cue
Delayed-response task:
The monkey is shown 2 lights in the choice test & must choose the one in the *same location* as the cue
Delayed-matching-to-sample task:
The monkey is shown a red light & then, after a delay, is shown a red & green light; must choose the *red* one
How does testosterone affect sexual behaviour?
The motivation to seek sexual activity Also needed to produce copulatory behaviour
How do we make something conscious?
The neocortical regions involved must receive feedback
Reconsolidation:
The process of restabilizing a memory trace after the memory is revisited New info is constantly being integrated into existing memory networks Perhaps we can reduce or eliminate effects of PTSD by erasing negative memories when the memory is revisited
HM:
The removal of HM's hippocampus, amygdala and the adjacent cortex resulted in amnesia Unable to recall anything that had happened since his surgery Was able to recall events from his childhood *No explicit memory* His experience was that of a person who perceives his surroundings but cannot comprehend the situation he is in because he does not remember what has gone before His implicit memory was nearly intact He was able to recognize faces, including his own Because *parahippocampal gyrus* on the right was left partly intact
Declarative memory:
The specific contents of specific experiences that can be verbally recalled
Patients with cortical abnormalities (but intact amygdala) were shown photographs of relatives:
These photographs were mixed in with strangers Although they did not recognize anyone, they were told to pick the one they liked the most, and always picked the relative
Why are they rewarding?
They increase the activity of neural circuits that function to maintain an animal's contact with certain environmental stimuli The animal perceives this as pleasant
Korsakoff's syndrome:
Thiamine deficiency kills cells in the medial part of the diencephalon (medial thalamus & mammillary bodies of hypothalamus) Frontal lobes often show atrophy as well Some patients have it so severe that the brainstem is damaged as well *Fabricated memories*, but often have some relation to real life (ex. man says he was a butcher, but really his son works as a butcher and he is a trucker) *Poor short-term memory* Both *retrograde & anterograde amnesia* Patients have little insight into their memory disturbance & are indifferent to such suggestions Generally *apathetic* to things going on
Thorndike's experiments with cats, before Skinner:
Thorndike was interested in how animals solve problems In one experiment, he placed cats in a box with a plate of fish outside it; cat needed to figure out how to get out of the box The solution was to press on a lever At first the cat pressed it only by chance; eventually learned its consequences
Studied brains with MRIs before & after taxi driver training:
Those who failed showed no hippocampal change Those who passed had increased volume
Long-term depression:
Use low-frequency stimulation & there's a decrease in EPSP size
Possible that dementia may reflect a chronic _____ condition
Vascular
Imagery about sexual activity must include activity in the dorsal/ventral visual pathway of the cortex
Ventral
The main input from the neocortex to the *perirhinal* region is from the visual regions of the dorsal/ventral stream
Ventral
Damage to the _____ hypothalamus causes *hyperphagia*
Ventromedial
Electrical stimulation to the _____ hypo inhibits feeding; _____ hypo to elicit feeding
Ventromedial Lateral
The _____ hypothalamus controls female mating posture, which in quadrapedal animals is called _____ (arching back & elevating rump)
Ventromedial Lordosis
Monkeys are trained to displace objects to obtain a food reward, and then are given 1 of 2 tasks; either the ____ task or the _____ task
Visual-recognition Object-position
A rat with self-stimulation in the lateral hypothalamus. Increases wanting or liking?
Wanting
Rats with lesions of DA pathways to the forebrain stop eating. Is this due to loss of wanting or pleasure?
Wanting
Glucocorticoids & stress:
With prolonged stress, appear to kill cells in the hippo Even brief periods of stress can reduce the # of granule cells in the hippo of monkeys; especially implicates *spatial memory*
LTP & LTD also work on ______
INH GABA interneurons
3 NTs influence explicit memory from brainstem:
1. ACh 2. 5-HT 3. NE
2 most important structures for cognition of feeding:
1. Amygdala 2. Orbital prefrontal
Organizing effects also operate on 3 other areas on the CNS:
1. Amygdala 2. Prefrontal 3. SC
7 guiding principles of brain plasticity:
1. Behavioural change reflects change in the brain 2. All NS are plastic in the same general way 3. Plastic changes are age-specific 4. Prenatal events can influence brain plasticity throughout life 5. Plastic events are brain-region dependent 6. Experience-dependent changes interact 7. Plasticity has pros & cons
3 major sources for the feeding control system in humans:
1. Cognitive factors 2. Hypothalamus 3. Digestive system
Neuroscientists believe that the mesolimbic DA system is central to circuits mediating reward for 4 reasons:
1. DA release shows a marked increase when animals are engaged in intracranial self-stimulation 2. Drugs that enhance DA release increase self-stimulation, whereas drugs the decrease DA release decrease self-stimulation; seems that the amount of DA released somehow determines how rewarding an event is 3. When animals engage in behaviours (ex. feeding), DA release rapidly increases in locations such as the nucleus accumbens 4. Highly addictive drugs (ex. nicotine) increase the level of DA in the nucleus accumbens
In one test, a monkey is shown a light (cue), and after a delay must then make a response to get a reward: 3 versions
1. Delayed-response task 2. Delayed-alternation task 3. Delayed-matching-to-sample task
Hypothalamus receives input from 3 places for feeding:
1. Digestive system 2. Hormone system 3. Cognitive
Plasticity has pros & cons: (3)
1. Drug addicts whose prefrontal is affected are prone to poor judgment 2. People with PTSD show altered blood flow in the amygdala & cingulate 3. Age-related dementia is related to synaptic loss that cognitive therapy can reverse
Alzheimer's disease is likely due to some combo of 4 things:
1. Genetic predisposition 2. Abnormal levels of trace elements 3. Immune reactions 4. Slow viruses
Explicit memory pathway: (5)
1. Hippo projects to EC 2. EC projects to parahippocampal & back to hippo 3. PHC projects to frontal, parietal, temporal, occipital & cingulate cortices, as well as back to EC 4. These cortices project to PC, as well as back to PHC 5. PC projects to EC, and back to cortices
2nd messengers by NMDA do 3 things:
1. Increased responsiveness of AMPA 2. Formation of new AMPA 3. Retrograde messages for more glutamate
Feeding is influenced by 3 main hormones:
1. Insulin 2. GH 3. Sex steroids
2 main sites of brain that produce reward:
1. Lateral hypo 2. Medial forebrain bundle
The digestive system extracts 3 types of nutrients from the mouth to the anus:
1. Lipids 2. Amino acids 3. Glucose
2 main neuronal changes occur in Alzheimer's disease:
1. Loss of cholinergic cells in the basal forebrain 2. Development of neuritic plaques in the cerebral cortex
Prefrontal has 2 roles in memory:
1. Maintenance of short-term explicit 2. Memory for the recency of explicit events
The amygdala projects to 4 places:
1. Medial temporal 2. Brainstem 3. Periaqueductal gray matter 4. Basal ganglia
A 26-year study looked at mortality in men & women and obesity:
A low-carb diet based on animal food sources was associated with a *higher mortality* A vegetable-based, low-carb diet was associated with *lower mortality*
Fear conditioning:
A noxious stimulus is used to elicit fear; often a mild electric shock When the tone is presented later without the shock, the animal acts afraid Because this response is emotional, circuits of the *amygdala* are active
Metaplasticity:
A property of a lifetime's interaction among different plastic changes in the brain
Learning:
A relatively permanent change in an organism's behaviour as a result of experience
Evolutionary view of episodic memory:
A researcher studying episodic amnesia proposed that this type of memory transforms the brain into a kind of time machine that allows us to dwell on the past & make plans for the future Believes that this is unique to humans
Pursuit-rotor task:
A small metal disc moves in a circular pattern on a turntable that also is moving The task is to hold a stylus on the small disc as it spins Amnesics fail to recall performing the task before, yet do better on it
Eye-blink conditioning:
A tone is associated with a painless puff of air to the participant's eye The tone is the conditioned stimulus The air puff is the unconditioned stimulus The blinking is the unconditioned response The participant communicates that it has learned that the signal stimulus predicts the puff by blinking in response to the CS alone; a conditioned response Circuits in the *cerebellum* mediate this learning; has circuits designed to pair various motor responses with environmental events
One study compared a low-fat diet, a low-carb diet and the Mediterranean diet (high in fruits, vegetables, legumes, whole grains, and low-fat dairy):
All 3 led to weight loss The low-carb produced the *largest acute weight loss* By the end of the 2 year study, low-carb & Mediterranean dieters had similar weight loss because low-carb gained some weight back Low-carb diet had more favourable effects on *lipid levels* Mediterranean diet provided better control of *glucose & insulin levels*
Damage to amygdala:
Alters food preferences & abolishes taste-aversion learning (related to the amygdala's efferent connections to the hypothalamus)
AMPA:
Always respond to glutamate and allow sodium ions to enter
Emotional memory mostly involves the ____
Amygdala
Sexual motivation is controlled by the _____
Amygdala
Learning set:
An *implicit* understanding of how a problem can be solved with a rule that can be applied to many different situations
When the ovaries of female rats are removed, *E levels drop*, producing...
An *increase* in the # of spines on pyramidal cells throughout the neocortex but a *decrease* in spine density in the hippo
Androgen-insensitivity syndrome:
An XY fetus produces androgens, but the body cannot respond to them These people are still responsive to estrogen produced by both the adrenal gland & the testes They develop female secondary sexual characteristics during puberty A *genetic male* with a *female phenotype*
Dyslexia:
An impairment in learning to read, and it's likely to most common learning disability
Osmotic thirst:
An increase in the concentrations of dissolved chemicals (*solutes*) in the body fluids The solutes from inside & outside the body are ideally concentrated for the body's chemical reactions When we eat salt foods, the NaCl spread through the body & enters the extracellular fluid; this shifts the solute concentration away from ideal
XX fetus with masculization is called _____ or _____
Androgenital syndrome Congenital adrenal hyperplasia
When the fluid volume drops, the kidneys send _____ that simulates _____ hypothalamic neurons
Angiotensin Midline
Evidence suggests that sex differences of the hypothalamus result from differences in _____
Gene methylation
____ can be used as a marker for when new cells are made
BrdU
_____ plays a role in maintaining appropriate levels of activity in the forebrain structures so that they can process info
Basal forebrain
_____ is vital for implicit memory
Basal ganglia
The ____ amygdala is especially imp for emotional memory
Basolateral
How can we initiate spontaneous recall for explicit?
Because explicit encoding is active, the internal cues that were used in the processing can also be used to initiate spontaneous recall
Rats without androgens during development:
Behave like female rats If given estrogen & progesterone, they display typical female behaviours like being sexually "receptive" to male mounting Male rats that are castrated in adulthood do not act this way
The Law of Effect:
Behaviour changes because of consequences Responses the produce a satisfying effect in a particular situation become more likely to occur in that situation, and responses that produce a discomforting effect become less likely to occur again in that situation
Behavioural compensation:
Behaviour has changed to compensate for some loss Ex. Person learns to use opposite hand to write Presupposes that some changes in the NS underlie this new skill
Sexual activity when cortices removed in rats:
Both males & female still engage in sexual activity
Plastic changes are age-specific:
Brain responds to same experiences at different ages Prefrontal cortex is late to mature
According to Robinson and Berridge, wanting is controlled by _____, whereas liking is controlled by _____. A) dopamine; serotonin B) norepinephrine; opioids and GABA C) dopamine; opioids and GABA D) dopamine; acetylcholine
C
Administration of ______ has been shown to help improve recovery from brain injury in animals. A) L-dopa B) steroids C) nerve growth factor D) All of the answers are correct
C
After brain damage, new connections can be encouraged by: A) pharmacological intervention. B) behavior therapy. C) both behavior therapy and pharmacological intervention. D) neither behavior therapy nor pharmacological intervention
C
Aphagia (lack of eating) can be produced by lesioning the: a. dorsal hypothalamus. b. anterior hypothalamus. c. lateral hypothalamus. d. ventromedial hypothalamus.
C
Brain-derived neurotrophic factor (BDNF): a. increases the number of new neurons. b. increases the size of axons. c. increases the number of dendrites and synapses. d. increases myelination.
C
Homosexual males have a hypothalamus that is organized: A) like a female hypothalamus. B) like a heterosexual hypothalamus. C) unlike either the heterosexual male hypothalamus or the female hypothalamus. D) like a lesbian hypothalamus.
C
If rats are given cocaine for 2 weeks prior to being placed in a complex environment, there is: A) an increase in dendritic length and dendritic spine density. B) a decrease in dendritic length and dendritic spine density. C) no change in dendritic length and dendritic spine density. D) an increase in the number of new axons.
C
In a conditioning experiment Andrew hears a tone just prior to receiving a puff of air to his eye that causes an eye blink response. In this experiment the tone is the ____, the puff of air to the eye is the ______ and the eye blink is the ______. a. conditioned response, conditioned stimulus; unconditioned stimulus b. unconditioned stimulus; conditioned stimulus; conditioned response c. conditioned stimulus; unconditioned stimulus; unconditioned response d. unconditioned stimulus; conditioned stimulus; unconditioned response
C
In recent studies the hippocampus has been implicated in: a. memory for faces. b. visual object memory. c. memory for places. d. verbal memory.
C
Matt has just finished running a marathon in the middle of a heat wave. Matt is extremely worried about getting dehydrated, so he starts to consume large amounts of water. Suddenly his heartbeat becomes irregular and he gets a severe headache. You tell Matt that he should: A) drink more water because he is probably very dehydrated. B) see a doctor because he might be having a heart attack. C) stop drinking water because he is experiencing water intoxication. D) start running again until the feeling goes away.
C
One of your friends routinely uses study pills (i.e., Ritalin) to help him stay awake and pull all-nighters during exam time. Normally if he takes a small dose he is fine, but lately when he takes the same dose he gets extremely agitated and cannot sit still. The same dose is having a larger effect on him than it used to. This is an example of: A) drug addiction. B) tolerance. C) behavioral sensitization. D) withdrawal.
C
Pressing a bar to obtain food is an example of: a. classical conditioning. b. respondent conditioning. c. instrumental conditioning. d. amygdala conditioning.
C
Research suggests that LTP increases synaptic effectiveness by: a. increasing the number of synapses on postsynaptic dendrites. b. increasing the firing rate of presynaptic neurons. c. increasing the size of axons. d. decreasing the amount of glutamate released by presynaptic neurons.
C
Your friend Devin (who is left-handed) has played the electric guitar for almost 20 years. If you conducted an MRI scan of Devin's brain, you would expect to see an increase in the size of his: A) hand region in motor cortex in the left hemisphere. B) basal ganglia in the left hemisphere. C) hand region in motor cortex in the right hemisphere. D) cerebellum in the right hemisphere.
C
_____ is probably the most common learning disability. A) Attention-deficit-hyperactivity disorde B) Autism C) Dyslexia D) Dyscalculia
C
Robinson & Berridge propose that reward contains separable psychological components:
Correspond to "wanting" (incentive) and "liking" (pleasure) Liking entail GABA systems
Brain scans for the 3 delayed tasks in monkeys:
Certain cells in the *prefrontal* fire throughout the delay depending on which task
Neurotrophic factors:
Chemical compounds that signal stem cells to develop into neurons & glia
Enriched environments in adult rats have been shown to increase the number of: A) neurons. B) synapses. C) blood capillaries. D) synapses and blood capillaries.
D
The hypothalamus sends signals that stimulate us to drink when thirsty, but also sends signals to the _____
Kidneys
When food reaches the intestines, it interacts with receptors there to trigger the release of at least 10 different peptide hormones & one is called _____
Chole*cysto*kinin (CCK)
Neuritic plaques:
Consist of a central core of homogenous protein material (*amyloid*) surrounded by degenerative cellular fragments Especially in *temporal-lobe* areas related to memory Often associated with *neurofibrillary tangles*
HM & language:
Couldn't learn new words ("jacuzzi")
A stimulus followed by food, followed by salivation, is a learning paradigm called: A) Pavlovian conditioning. B) classical conditioning. C) respondent conditioning. D) All of the answers are correct.
D
Amnesiacs generally lose the ability to do: a. explicit and implicit memory tasks. b. implicit memory tasks. c. any verbal-content tasks but not motor tasks. d. explicit memory tasks.
D
Another word for explicit memory is: a. skill. b. reference. c. habit. d. episodic memory.
D
Anterograde amnesia, retrograde amnesia, confabulation, meager content in conversation, lack of insight, and apathy are symptoms related to A) Tourette's syndrome B) Alzheimer's disease C) Huntington's syndrome D) Korsakoff's syndrome E) None of the above
D
Brain tissue transplant has shown some promise in treating: A) Alzheimer's disease. B) Huntington's disease. C) anterograde amnesia. D) Parkinson's disease.
D
Changed amplitude (an increase) of an excitatory postsynaptic potential that lasts for hours to days or longer is called __________. a. associative learning b. long-term depression c. neurogenesis d. long-term potentiation
D
Cortical representation of motor parts (e.g., fingers): A) is fixed during development. B) can be altered by experience. C) can be altered by amputation of a limb. D) can be altered by both experience and amputation of a limb.
D
Damage to the ventromedial hypothalamus leads to: A) digestive problems in animals. B) animals not eating. C) anorexia nervosa. D) overeating in animals.
D
Even when cortical/limbic structures are intact, loss of neurons in the _____________, _______________, or ___________ systems can be a cause of amnesia related to autobiographic or semantic memory. A) cholinergic, dopaminergic, noradrenergic B) cholinergic, dopaminergic, serotonergic C) dopaminergic, serotonergic, noradrenergic D) cholinergic, serotonergic, noradrenergic E) serotonergic, dopaminergic, noradrenergic
D
Gonadal hormones can have organizing effects on the: A) hypothalamus. B) spinal cord. C) amygdala. D) hypothalamus, spinal cord, and amygdala.
D
If the amygdala were to be damaged, there would be A) impairment in autobiographical memory but intact emotional and motor memory B) impairment in explicit memory but intact emotional and implicit memory C) impairment in implicit memory but intact explicit and emotional memory D) impairment in emotional memory but intact explicit and implicit memory E) none of the above
D
If you want to increase children's ability to learn later in life, a good option would be to: A) get them involved in sports. B) teach them to play a musical instrument. C) encourage them to read often. D) All of the answers are correct.
D
Neurotrophic factors: A) reorganize neural circuits. B) are produced by neurons. C) are produced by glial cells. D) All of the answers are correct.
D
Once Melissa was trapped in an elevator all alone for almost 3 hours when the power went out. Now whenever she gets near an elevator, she freezes up and starts gasping for air as if she cannot breathe. This is an example of: a. operant conditioning. b. respondent conditioning. c. classical conditioning. d. fear conditioning.
D
Patients with Korsakoff's syndrome have problems with: A) only autobiographical memories B) implicit C) explicit D) both
D
Patients with lesions to the orbital prefrontal cortex typically become: A) overweight. B) picky eaters. C) indiscriminate eaters. D) very slim from undereating.
D
Pavlovian conditioning is controlled by circuits in the: A) frontal cortex. B) thalamus. C) brainstem. D) cerebellum.
D
Repeated exposure to amphetamine or cocaine: a. decreases spine density in the frontal cortex. b. All of the answers are correct. c. results in a lesser response over time. d. results in a long-lasting change in the brain.
D
Reward is thought to be regulated largely by the: A) nigrostriatal dopamine pathway. B) serotonin pathway. C) norepinephrine pathway. D) mesolimbic dopamine pathway.
D
The _______ prefrontal cortex is more involved in _____ information. A) left; retrieving B) none of the above C) right and left; encoding D) left; encoding E) right; encoding
D
The inability to acquire new memories A) time-dependent retrograde amnesia B) fugue state C) retrograde amnesia D) anterograde amnesia E) transient global amnesia
D
Transplanting brain tissue: A) works as well as transplanting other organs. B) effectively reverses Parkinson's disease. C) is especially effective in the cortex. D) is not a very effective technique.
D
Which of the following areas first shows cell death in Alzheimer's? A) hippocampus B) perirhinal cortex C) parahippocampal D) entorhinal
D
Plastic events are brain-region dependent:
Drugs change the prefrontal, dorsolateral & orbital prefrontal Stimulants increase spine density in the *dorsolateral* but decrease in the *orbital*
When the gonads of male rats are removed, increase/decrease in cortical spine density
Decrease
Encoding explicit memory:
Depends on conceptually driven, or *top-down*, processing The person reorganizes the data The "top" influences how the incoming ("bottom") information is processed *Active*
The hypothalami of homosexual males:
Differ from both females & heterosexual males
Sexual dimorphism:
Differential development of brain areas in the 2 sexes
Could also use DBS or direct electrical stimulation:
Directly increases activity in remaining parts of the specific, damaged neural networks In DBS, the brain is put into a more "plastic" state so that rehabilitation works better
Damage & stimulation to medial preoptic in males:
Disrupts mating performance, whereas electrical stimulation activates mating (as long as testosterone is in the blood) Even if the medial preoptic area is destroyed, they continue to show some interest
The ______ theory suggests that a learning episode rapidly creates a stored memory representation that is *strong in the hippo*, but weak elsewhere
Distributed reinstatement
NMDA:
Do not usually respond to glutamate because their pores are blocked by magnesium Need to have the membrane be depolarized for this to be removed, then glutamate can activate (double-gate) Calcium ions enter through NMDA to act on 2nd messengers
A patient w/ severe cortical damage but an intact amygdala would have A) impaired autobiographical memory but intact semantic memory B) impaired implicit memory but intact episodic emotional memory C) impaired working memory but intact motor memory D) none of the above E) impaired explicit memory but intact implicit emotional memory
E
Damage to the ___________ is generally associated with memory disturbance A) frontal cortex B) prefrontal cortex C) occipital cortex D) parietal cortex E) temporal cortex
E
For emotional memory, the cholinergic and noradrenergic systems stimulate the amygdala to lay down memory circuits in the ______________. A) medial temporal and the parietal regions B) posterior temporal and hypothalamus C) none of the above D) posterior temporal and the hippocampal regions E) medial temporal and prefrontal regions
E
In regard to emotional memory, the _______________ is critical. A) ventromedial part of the amygdala B) dorsolateral part of the prefrontal cortex C) orbitofrontal part of the prefrontal cortex D) ventromedial part of the hippocampus E) basolateral part of the amygdala
E
The __________ consolidates memories; the _________ stores them. A) amygdala; hippocampus B) hippocampus; amygdala C) neocortex; hippocampus D) none of the above E) hippocampus; neocortex
E
Enriched experience & plasticity:
Enriched environments for lab animals perform better on maze tasks; increase in brain weight (in part because of exercise alone) Using a microscope to study the cells, a coordinate change occurs not only in the extent of dendrites but also in *glial, vascular & metabolic* processes in response to differential experiences *More synapses per neuron* More *astrocytes, blood capillaries & higher mitochondrial* volumes When looking at hippocampi after rats placed in either complex-housing or cage-housing, those in the complex had *more neurons*
The ____ cortex is the first cell death seen in Alzheimer's
Entorhinal
The neurotrophic factor that stimulates the subventricular zone to generate cells that migrate into the striatum and eventually differentiate into neurons and glia is termed the _____ growth factor
Epidermal
The opposite of procedural memory is _____ memory
Episodic
_____ masculinizes the male brain
Estradiol
Women's performance on various cognitive tasks changes throughout the menstrual cycle as their estrogen levels fluctuate:
Estrogen alters the structure of neurons & astrocytes in the neocortex & hippocampus As E rises, the # of synapses (dendritic spines) rises
Generation of new neurons in hippocampus when animals learn explicit/implicit tasks
Explicit
Associative learning:
Explicit memory Enduring neural change in a post-synaptic cell after an EPSP
Differences in the hypothalamus may form a basis for _______
Gender identity
Researchers measured the methylation in the hippocampi of rats that underwent contextual fear conditioning:
Fear conditioning is associated with *rapid methylation*, but if they blocked methylation, there was no memory Epigenetic mechanisms mediate synaptic plasticity broadly, but especially in learning & memory
On average, verbal abilities of males/females are superior (more branching)
Females
Why are females not masculinized?
Females are not masculinized by the presence of estrogens because the fetuses of both sexes produce a liver enzyme (*alpha fetoprotein*) that binds to estrogen Incapable of entering neuron Testosterone is unaffected by alpha fetoprotein, so it enters neurons
Many musicians develop _____ (abnormal finger & hand positions, cramps and difficulty in coordination)
Focal hand dystonia
Dendritic structure of neurons in different cortical regions that handle different computational tasks:
For the somatosensory representation of the trunk with those for the fingers, the latter is more complex The inputs from receptive fields on the chest wall would constitute less of a computational challenge to cortical neurons than would those from the fingers; so chest neurons are less complex
Lashey's memory experiments:
Found that memory disturbance was related to the size of the injury rather than to its location Failed to find location of the memory trace
People with ____ injuries have difficulties with memory for temporal order of events (explicit/implicit)
Frontal Explicit
All sensory regions in the brain project to the _____ & _____
Frontal Medial temporal
The _____ lobe is for short-term and the ____ lobe is for long-term verbal
Frontal Temporal
Thinking about sex & planning for it require the ______
Frontal lobes
People with ____ injuries often suffer from episodic memory loss
Frontal-lobe
CCK makes you feel hungry/full
Full
Creating novel circuits: songbirds
Grow new neurons to produce songs in the mating season
In birds and rats that store food, the _____ is larger
Hippocampal formation
Monkeys with _____ lesions cannot do the object-position task
Hippocampal formation
In recent studies, the _______ has been implicated in memory for places.
Hippocampus
The ____ deals with visuospatial memory processes for places
Hippocampus
The ____ & _____ are among the regions that normally produce new neurons in adulthood, and experience can influence how many are produced
Hippocampus Olfactory bulb
There are also people with "super" autobiographical memory, called _____ syndrome
Hyper*thymestic*
Animals that have damage to the ventromedial hypothalamus tend to overeat, a symptom known as ______
Hyperphagia
The _____ & _____ of a male rat differ structurally of both female rats & male rats that were not exposed to androgens
Hypothalamus Prefrontal cortex
There are two different types of thirst. When the total volume of body fluids decline, this produces what is known as ______ thirst.
Hypovolemic
When sensory nerves in one limb are severed in monkeys, large-scale changes in the somatosensory makes ensue:
In the absence of input, part of the cortex no longer responds to stimulation of the limb; but this does not mean it's inactive The deafferentated cortex begins to respond to input from other body parts (ex. hand area now responds to face touching) These results explain amputees (phantom limb pain)
One study used resting-state fMRI to identify a limbic network & discrete prefrontal networks believed to support reward:
In those addicted to nicotine, there's greater connectivity in the *prefrontal-striatal* connections and in the *limbic* pathway
Encoding implicit memory:
In very much the same way as it is perceived & can be described as data-driven, or *bottom-up*, processing Information enters the brain through sensory receptors & then is processed in various regions *Passive*
Rats would perform behaviours such as pressing a bar to administer a brief burst of electrical stimulation to specific sites in their brains; called _____ or brain-stimulation reward
Intracranial self-stimulation
Researchers have designed a remedial treatment program based on the fundamental problem in auditory processing:
Involves learning to make increasingly difficult sound discriminations, like "ba" and "da" As the delay between the sounds grows shorter & shorter, discrimination becomes more and more difficult Training stimulates neural plasticity Improves both phonological processing & produces compensatory activation in related brain regions
Water intoxication:
Kidneys cannot keep up if we consume large amounts of water at once Body tissues swell with excess fluid, drowning the cells in fresh water At the same time, the concentration of sodium drops, leading to an imbalance of electrolytes Symptoms range from irregular heartbeat to headache; in severe cases, people act as if they're drunk
People who have abused alcohol may develop an explicit-memory disturbance known as _____ syndrome (if bad enough, implicit too)
Korsakoff's
Damage to the _____ hypothalamus causes *aphagia*
Lateral
More recently, non-invasive imaging has determined that activity is reduced in the _____ cortex in those with dyslexia
Left temporoparietal
The long-lasting decrease in synaptic effectiveness after low-frequency electrical stimulation is termed ____
Long-term depression
Damage to the orbital prefrontal:
Lose weight, partly because they eat less Because odours influence the tastes of foods, it is likely that damage to the orbital prefrontal decreases eating because of diminished sensory responses
Low/high E leads to decreased verbal memory
Low
Several hypothalamic nuclei are 2-3x larger in males/females
Males
The preoptic area of the hypothalamus is larger in males/females
Males
Same study with rats & lever, but amygdala lesioned instead:
Males would no longer press the bar, but would mate with receptive females if they were present
Transsexuality:
Many factors lead to changes in the architecture & function of brain structures, especially the hypothalamus
Dementia & vascular:
Marginal high BP can lead to cerebral *microbleeds*, especially in white matter
Research has found that professional pianists have not only better motor skills in their fingers, but also enhanced somatosensory perception as well:
Measured ability to detect subtle sensory stimulation at fingertips Musicians were more sensitive than controls Also enhancement in tactile sensitivity was related to hours per day that the musicians practiced When given a training session designed to improve tactile sensitivity, the musicians showed more improvements Rather than using up the available synapses, they develop the capacity to make even more
The _____ hypothalamus in males control copulation
Medial preoptic
Temporal pathway is reciprocal from the _____ to the ____ (& back)
Neocortex Entorhinal
Long-term memory storage is in the _____, but *consolidation* is in the ______
Neocortex Hippocampus
In the brains of deceased people with a college education...
Neurons in Wernicke's area had more dendritic branches than did those from people with a high-school education
In a study, placed a patch over one eye of a rat & then trained them in a maze:
Neurons in the trained visual cortex had more dendrites Some feature associated with encoding, processing or stage of visual input was responsible for forming new synapses (nothing else in the brain changed)
Explicit is to implicit as semantic is to _______
Non-associative
Sexual behaviour is regulatory/not
Not
The mesolimbic DA pathway sends terminals to many sites, especially the _____ & the _____
Nucleus accumbens of the basal ganglia Prefrontal cortex
Implicit memory:
Participants demonstrate knowledge, but cannot explicitly retrieve the information People with amnesia perform normally on implicit tasks
In one study, participants were shown a video of a car colliding with another car that was stopped; one group is asked to estimate how fast the car was going when it "smashed" into the other car; one group when it "bumped" into the other car:
Participants looking at "smashing" cars estimate speeds faster than "bumping" In both cases, participants were very certain that their memories were correct
We can also show how implicit memory is fallible:
Participants read a list of words; after, they hear another list of words & need to indicate which ones are new Fail to identify new ones because they seem to fit with a theme Studies like these seem to form "false memories" & participants defend their veracity with certainty
Implicit memory can be recalled more easily if there's _____ of the original stimulus
Priming
During estrous cycle, peak of sexual receptivity is when ____ & ____ levels are highest
Progesterone Estrogen
Behavioural sensitization:
Progressive increase in behavioural actions in response to repeated administration of a drug Behaviours increase when the amount given in each dose does not change This occurs with most psychoactive drugs (nicotine, cocaine, etc)
Basolateral amygdala:
Receives ACh & NE
Explicit is to implicit as working is to _____
Reference
Long-term potentiation:
Repeated electrical stimulation of the pathway entering the hippocampus produces a progressive increase in EPSP size recorded from hippocampal cells The enhancement in the size of these "field potentials" lasts for a # of hours to weeks or longer Long-lasting increase in synaptic effectiveness after *high-frequency* stimulation
Explicit is to implicit as _____ is to dispositional
Representational
Hypovolemic thirst:
Results from a loss of overall fluid volume from the body Arises when the total volume of body fluids declines, motivating us to drink & replenish them This thirst encourages us to choose something other than water, because water would dilute the solute concentration in the blood
Skinner's experiments:
Skinner used reinforcement to train rats to press bars or pigeons to peck keys
BDNF:
Some researchers believe that BDNF has a role in learning, but this might not be true
Consolidation:
Stabilizing a memory trace after learning Movement of memory into neocortex
Consolidation & storage of memories is likely to take place at the _____
Synapse
Low/high T leads to decreased spatial ability
T
Explicit is to implicit as locale is to _____
Taxon
Ventral stream in the _____ cortex is for ____ memory
Temporal Visual object
Organizing effect of gonadal hormones during prenatal development:
The Y chromosome controls the differentiation of embryonic gonad tissue into testes, which secrete testosterone
Memory:
The ability to recall/recognize previous experience Implies a mental representation of the previous experience, sometimes referred to as a *memory trace* Corresponds with some physical change in the brain (synapses)
Operant conditioning:
The animal demonstrates that it has learned the association between its actions & the consequences by performing the task faster Not localized to any particular circuit; the circuits needed vary with the requirements of the task
Visual-recognition task:
The animals displace a sample object to obtain a food reward & after a delay, the animal is presented with 2 objects and must displace the *novel* object
Processing memories:
The brain does not process all implicit or all explicit memories the same way There are also short-term & long-term memory distinctions
Explicit memory:
The conscious recollecting of training People with amnesia perform abnormally
If animals are trained to make certain digit movements over & over...
The cortical representations of those digits expands at the expense of the remaining motor areas
If rats are given psychoactive drugs for 2 weeks before being placed in complex environments...
The expected increases in dendritic length & spine density do not happen *The brain can no longer change*: giving the animals additional drug doses can still produce change Rather, something about prior drug exposure alters the way in which the brain later responds to experience
What happens if glucose isn't in the blood for the brain?
The liver acts as a short-term reservoir of *glycogen*, a starch that acts as an inert form of glucose When the blood-sugar levels fall, detector cells tell the liver to release glucose (converts glycogen)
Distributed reinstatement theory:
The memory is replayed on the time scale of hours or days after the learning, leading to enhanced representations outside the hippo With each repetition, progressively enhances the non-hippo memory So if the hippo is destroyed, the memory remains
While studying the motor cortices of monkey brains, researchers found individual differences in topography:
Trained them to retrieve food from either a small or large food well The monkey was able to insert its whole hand into the large one, but only 2 fingers in the small one Those on the small well improved with practice, making fewer finger flexions per food retrieval as training proceeded Maps of forelimb movements were produced by microelectrode stimulation of the cortex *Changes in the maps for the small well monkeys, not the large* The functional topography of the motor cortex is shaped by learning *new motor skills, not repetitive motor use*
Also possible to generate new neurons to produce new neural circuits:
Transplant brain tissue from one another to another (fetal) Unfortunately so far, this technology functions very poorly; procedure works best in conditions in which a small # of cells are required (DA-cells in Parkinson's or replacing suprachiasmatic cells to restore circadian rhythms)
An atypical form of gender identity is _____
Transsexuality
The general term for damage to the brain from a blow to the head is called _____
Traumatic brain injury
Nerve growth factor:
Trophic in the sense that is stimulates neurons to grow dendrites & synapses It promotes the survival of neurons
Storing memories:
We expect that areas the process information also house the memory of that information In one study, participants were shown black & white line drawings & asked to generate words denoting either colours or actions of the objects while using a PET scan The idea is that processing colour & motion are carried out in different locations in the temporal lobe Recall of *colours* activated the *ventral temporal* lobe Recall of *actions words* generated activity in the *middle temporal gyrus*
How does osmotic & hypovolemic thirst differ?
We prefer drinks that contains salts & other nutrients for *hypovolemic*
One 20-year study looked into which foods were most likely to lead to weight gain:
Weight gain was strongly related to the intake of potato chips, potatoes, sugar-sweetened beverages, and red meat Weight loss was related to intake of vegetables, whole grains, fruits, nuts & yogurt Lifestyles related to weight change included the amount of TV watched (gain) and physical activity (loss)
Adult stem cells are a 2nd way to replace lost neurons:
When the correct trophic factors are added to cells that have been removed from the ventricles, the cells divide into neurons & glia If the *epidermal growth factor* is infused into the living animal, the subventricular zone generates cells that migrate into the striatum & differentiate