Neuroscience Exam 3

Why has it been difficult to develop effective drugs for psychiatric disorders? List a few reasons.

--Reason number one is we don't really know what the cause of the disorders is, only the symptoms!!! It is difficult to develop a drug if you don't know what to target—most drugs in use were discovered by accident and we're still not sure why they work! --There is a genetic component to these disorders, but it appears to be multigenic and seems to depend on an individual's experience together with genetic makeup, therefore can't pinpoint a specific target. --There is a broad spectrum of symptoms that aren't readily put in any single category, and therefore seemingly similar disorders may be due to different causes. There is also some overlap/co-morbidity between different disorders. --Related to above, it is hard to diagnose disorder since it mostly depends on self-reporting, unlike blood tests for diabetes which is objective, for example. --Others?

In adults, how many motor neurons innervate a single muscle fiber? In adults, how many muscle fibers does a single motor neuron innervate?

1 >3

Progenitor radial glial cells in the neural tube can divide symmetrically or asymmetrically. A. The gene Aspm has been under positive selection in primate evolution. The Aspm alleles selected for in primate evolution increase the number of symmetrical cell divisions of progenitor cells in the neural tube. What effect do you think this might have on development of the cerebral cortex (how would cortex be changed)? B. What if there were instead fewer symmetrical progenitor cell divisions, but more asymmetrical cell divisions?

A. more symmetrical divisions = more progenitor cells = expanded horizontal (or surface) area of cortex; this results in expansion of cortex surface area and therefore more gyri/sulci in humans vs rodents. B. asymmetrical results in neural progenitors which migrate to superficial layers; if greater numbers of asymmetrical divisions, cortex thickness will increase, but not surface area

Spina bifida is caused by the failure of the posterior neural tube to close properly during development. What do you think would happen if the anterior neural tube doesn't close?

Anencephaly ("no brain"); since anterior neural tube becomes the brain, if it does not close the brain will not develop properly and typically is very small

It is not uncommon for people to suddenly feel fear or anxiety for no obvious reason (and they then try attribute it to something happening around them). Can you come up with a reasonable explanation for this?

Association learning/fear conditioning can occur without being consciously aware of the sensory input, especially if a person's attention is on something different at the time, or cue provided for too short a period to be consciously noted, or possibly they just don't remember it.

Ephrins inhibit axons by binding to Eph receptors. Explain why retinal ganglion axons that express lower levels of EphA receptors are able to grow into areas of higher concentration of ephrin A in the tectum, than axons that express higher levels of EphA.

Both EphA receptors and ephrins are embedded in the cell membranes and contact between the EphA receptor on the retinal axons with ephrin in the tectum cells inhibits axon growth. The more EphA receptors that contact ephrins, the greater the growth inhibitory signal. If there are few EphA receptors on the ganglion axons, there is a low probability of the receptors contacting the ephrins, so little growth inhibition occurs until reaching areas of higher ephrin levels. If a growth cones had twice as many EphA receptors, that would double the probability of contacting the same amount of ephrins and therefore growth would be inhibited in a region of half the ephrin amount, so couldn't make it to areas of higher concentration.

Children born into low income families tend to be exposed to higher stress levels during childhood, and are more likely to have anxiety disorders as adults. Explain the mechanism for how early life stress is might lead to increased anxiety in adulthood.

Early life stress is thought to decrease the expression of glucocorticoid receptors in the hippocampus. Normally if stressed or become anxious, the amygdala signals through the hypothalamus, causing a release of hormones from the pituitary that lead to increased sympathetic nervous system responses and cortisol levels. Normally the cortisol binds to the glucocorticoid receptors in hippocampus and this leads to an inhibition of the stress response by feedback to the hypothalamus. Therefore, if fewer glucocorticoid receptors in hippocampus, the stress response stays longer and stronger.

What's the difference between a "feeling" and an "emotion" (hint, can study emotion in animals like rats)?

Feelings are more related to experience and conscious awareness, while emotion refers to the body's and brain's complex reactions to certain stimuli which can be unconscious, yet be manifest in body changes specific to an emotion.

In the TV clip that you saw, the narrator talked about there being "an overproduction of cells just before puberty" in the forebrain and Dr. Giedd says the overproduction is manifest in the thickening of the gray matter in the forebrain. Propose an alternative hypothesis for the thickening of the gray matter (rather than more neurons being produced)?

Increased branching of axons and dendrites, and possibly more synapses formed

Do you disagree or agree with the following statement? Explain why. Secretion of proteins from a presynaptic cell causes the clustering of post-synaptic neurotransmitter receptors and therefore presynaptic neurons are responsible for initiating synapse formation.

It is true that protein secretion from the presynaptic cell can initiate clustering in the postsynaptic cell, but the postsynaptic cell can also secrete/express proteins that attract and bind to the presynaptic cell, so there is bidirectional communication and both are somewhat involved in initiation.

When we say "cheese" it moves our mouth in a way similar to a smile, and it can actually make you feel happier. Which theory would this fit with, and why?

James-Lange theory By saying cheese our mouth position is in a similar orientation to when we smile, which occurs when we are happy. Feedback from our physiology (e.g., mouth in a smile) causes us to feel like we are happy.

You have been playing an intense video game, but now stop to take a break and relax. What areas of your brain would you expect to now have increased activity (after you quit doing the video game)? For each of those brain areas, indicate what functions are thought to be associated with that area.

Medial prefrontal cortex: planning, emotions Posterior cingulate: haven't talked much about this, but cingulate involved in feelings of wellbeing, pain, etc., frontal cortex involved in planning "posterior parietal cortex": this includes Wernicke's area, language? Overlaps also with area MT, movement perception? Temporal lobe areas: object recognition, memory, etc.? Hippocampus: memory formation and spatial memory

A patient has had a stroke, has difficulty speaking, and has all the signs of classic Broca's aphasia, based on their speech patterns. They can still understand language well, based on their responses to things the Doctor asks the patient to do. The doctor learns that the patient is excellent at sign language, and their hand use and coordination seems unimpaired. Do you think the patient will be able to communicate well by signing? Why or why not?

No. If patient has aphasia it will likely affect all forms of language production, which could include speech, writing and sign language. (Alternatively if have poor speech is due to muscle control issues in the mouth and tongue, it is not considered aphasia.) There is evidence that deaf people who sign are affected by the same language areas, but may involve more right hemisphere.

There are several treatments available for anxiety disorders and depression. Treatment of anxiety disorders are more likely to be successful, especially if the anxiety triggers can be identified (even though it takes a higher dose of SSRI drugs to effectively treat anxiety than to treat depression). Can you guess why the various treatments can be more effective in treating anxiety than depression?

One major reason is that counseling/psychotherapy can directly work on the triggers for anxiety (if identified), by training the person to not associate the cue/trigger with a bad outcome, such as slowly exposing them to the stimuli over time, as well as talk therapy. With depression there typically isn't a specific trigger... You might be able to come up with other reasons as well...

In our culture a surprising number of people know about dopamine. Two albums recently came out entitled "Dopamine" (by Third Eye Blind and BØRNS), as well as the song "Dopamine" by Yoav. Most people say dopamine levels are correlated with pleasure (especially related to drugs). What would you tell your friends to properly explain the role of dopamine in the brain?

Pleasure isn't directly related to dopamine levels. After conditioning it becomes more related to anticipation of something good. How dopamine is involved in all this is actually pretty complicated and not completely understood...

You are assessing the cognitive functioning of a patient who had their corpus callosum severed in order to reduce epileptic seizures. You ask the patient to pick up a coffee cup in front of them with their left hand. Do you think they will perform the command? Explain your reasoning for coming up with this answer.

Possibly... (can answer a couple of ways...) A. Probably no: Language likely processed in left hemisphere and can't send information to right hemisphere to initiate movement (left side controlled by right motor cortex). B. Maybe yes: some rudimentary language ability in right hemisphere which enables non-verbal responses to non-complicated commands, but maybe not so since identifying coffee cup and picking it up is more difficult than just pointing to or touching object, as in example in book.

Your friend did poorly on her Organic Chemistry exam two weeks ago, and you are concerned about her because she is clearly unhappy, says she is depressed and is very down on herself, and has been this way every time you've met her in classes. Based on this description, do you think a Psychologist would classify her as suffering from depression? Why or why not?

She probably could be classified as depressed in a clinical sense because she has exhibited the symptoms for two weeks. The second part of the clinical diagnosis is that the symptoms include a disruption of normal occupational or social activities. Since the student is attending classes, it may not be severe enough to be called depression, but there is not enough information here to make such a determination (other symptoms are considered...).

Your friend has quit attending most of his classes the past three weeks and doesn't want to do much of anything. You ask him what's wrong, and he says "nothing", he just is feeling a little down. You also know he hasn't been sleeping well. Based on this, would you suspect he may suffer from major depression? Why or why not?

Since he has suffered more than 2 weeks, and his normal "occupational" functioning (attending classes) is affected, he likely is suffering from major depression (these are the 2 hallmarks from diagnosis manual). He also has other symptoms of depression (sleep disruption, feeling down). He does not have other more severe symptoms (e.g., suicidal), but not everyone will have the same symptoms, and therefore sometimes depression is under-reported thinking it is not serious (but it is if interfering with normal work/social life)

Suppose a motor neuron has initially innervated nine muscle fibers during development. At three of these muscle fibers it is receiving substantial neurotrophic signaling (NT-4/5) and at the other six it is receiving negligible NT-4/5. What do you think will be the outcome for this motor neuron and the synapses it has initially formed?

Since it is receiving significant amounts of NT-4/5, it likely will survive, but will be pruned, with the 6 synapses not receiving neurotrophin being pruned away, and the other three becoming strengthened and will remain.

A person had a very specific injury confined to the classic Broca's area (Brodmann areas 44 and 45 in left cortex). What would you guess would be the approximate probability that they would have Broca's aphasia? a. 96% b. 90% c. 50% d. 10%

There is a lot of variability in the exact areas used for language, even though the majority is in the left hemisphere (e.g., lower than 96% since only 70% lefties have left hemisphere dominant). Evidence for this is variable responses to brain stimulation that interrupt language and even in class Broca case, damage was more extensive than to just Broca's area.

What does it mean, in neural terms, to be addicted to chocolate?

Things that make us think of chocolate would trigger increased firing of dopaminergic neurons in VTA in anticipation of reward. If get no chocolate, then actually have decrease in dopamine, which may be related to craving chocolate. HOWEVER, to be addicted you should also have other symptoms in addition to craving, such as negative psychological and physical symptoms if without chocolate (withdrawal symptoms), and chocolate eating is compulsive despite negative consequences.

You spot the difference between a genuine ("Duchenne") smile elicited by humor and a "fake"(pyramidal) smile by watching a person's eyes. In a genuine smile there is a contraction of obicularis oculi muscles around the eyes along with the lip movements, but those muscles don't normally contract with a fake smile. Briefly explain why this occurs, related to the brain and motor control pathways.

Voluntary control of facial muscles (fake smile) involves projections from the primary motor cortex, while a genuine smile involves projections from medial prefrontal cortex and the hypothalamus which control a broad range of facial muscles

It is known that Zika virus uses the AXL protein to infect human skin cells, so the virus might use this same receptor to enter radial glial cells in the developing brain, too. AXL in radial glia is localized to structures called end-feet, which come into contact with blood vessels along the neural tube. Based on this information, propose a hypothesis for why Zika virus causes microcephaly.

Zika is able to enter into radial glia because of the AXL protein at endfeet by bloodstream where virus is. Zika may affect AXL function directly or get into the cell and inhibit function so that cell divides less, therefore have reduced gliogenesis and neurogenesis, so less surface area and thickness of cortex, therefore smaller brain. Alternatively the virus once in the cell may just kill the radial glia. Could also propose affect on cell migration, since radial glia required for that process.

The axons from retinal ganglion cells in the frog eye will regenerate and grow back after the optic nerve is cut. If you cut the optic nerve and rotate the eye 180 degrees, what will happen when the axons regenerate? a. Axons from nasal retina will grow to the same area in the superior colliculus that nasal retina neurons innervated initially b. Axons from nasal retina will now grow to the area of the superior colliculus previously innervated by temporal retina axons c. Axons will regrow, but will extend randomly and not find their way to innervate the superior colliculus

a. Axons from nasal retina will grow to the same area in the superior colliculus that nasal retina neurons innervated initially

Which are two major classes of drugs used to treat anxiety? Choose the correct option. a. Benzodiazepines and serotonin-selective reuptake inhibitors b. Tricyclic compounds and MAO inhibitors c. MAO inhibitors and lithium d. Lithium and tricyclic compounds

a. Benzodiazepines and serotonin-selective reuptake inhibitors

What do amphetamines and cocaine have in common? a. Both inhibit the re-uptake of neurotransmitters b. Both increase the release of dopamine from presynaptic terminals c. Both activate glutamate receptors d. Both block GABA receptors, so reduce inhibition at synapses

a. Both inhibit the re-uptake of neurotransmitters

Which of the following people would be considered to have aphasia (there may be more than one correct answer): a. Can understand what other people are saying, but has difficulty responding, even though mouth and tongue movement are normal b. Difficulty in speaking, but can communicate by writing well c. Have a difficult time understanding what people are saying (can respond to sounds), but can speak fluently d. Blind, deaf, and dumb

a. Can understand what other people are saying, but has difficulty responding, even though mouth and tongue movement are normal c. Have a difficult time understanding what people are saying (can respond to sounds), but can speak fluently

Which of the following is derived from "telencephalon"? Choose the correct option. a. Cerebral hemispheres b. Thalamus c. Eyes d. Hypothalamus

a. Cerebral hemispheres

Which of the following statements about the amygdala are correct? (there may be more than one correct answer) a. Changes in synaptic strength occur after fear conditioning with a tone in the amygdala, causing enhanced synaptic responses to the tone after the conditioning. b. Outputs from the amygdala include connections to hypothalamus that can cause changes in motor behavior. c. Sensory input to the amygdala comes from primary sensory cortex and association cortices only, not directly from the sensory pathways. d. Associative learning in the amygdala can result from a direct pairing of unpleasant (e.g., a painful shock) or pleasant (taste of good food) stimuli together with neutral (conditioned) stimuli.

a. Changes in synaptic strength occur after fear conditioning with a tone in the amygdala, causing enhanced synaptic responses to the tone after the conditioning. b. Outputs from the amygdala include connections to hypothalamus that can cause changes in motor behavior. d. Associative learning in the amygdala can result from a direct pairing of unpleasant (e.g., a painful shock) or pleasant (taste of good food) stimuli together with neutral (conditioned) stimuli.

In the formation of of synapses in the CNS, what is typically the first thing that happens in order to initiate synapse formation. a. Contact between an extending filopodia on a dendrite and an axon b. A growth cone needs to "find" and contact a cell body c. NGF release from a dendrite attracts an axon d. Clustering of postsynaptic receptors occurs first, which attracts contact from axon filopodia

a. Contact between an extending filopodia on a dendrite and an axon

What did Gazzaniga and colleagues reveal about hemispheric dominance for language in his studies of humans in whom the corpus callosum had been severed? Choose the correct option. a. If a split-brain person sees a word in the left visual field, he usually says he sees nothing. b. If a split-brain person sees a word in the right visual field, he says he sees nothing. c. The right hemisphere knows nothing about language. d. The left hemisphere can read words, but the right hemisphere is necessary to speak the words.

a. If a split-brain person sees a word in the left visual field, he usually says he sees nothing.

You are playing a game where every time you hear a high-pitched tone you must quickly press a button. The quicker you press the higher the score. You must do this while talking to an experimenter. There will be 100 participants and whoever gets the highest score wins an iPad. How do you think your brain responds to that tone during the game, compared to randomly hearing the tone while talking to the experimenter before learning the rules/competing? a. Increased responsiveness of primary auditory cortex neurons that respond to that tone. b. Increased activity in the auditory association cortex to the high tone, but not in the primary auditory cortex. c. No change in brain activity in response to the high tone itself, but heightened brain activity in the right parietal lobe. d. No change in brain activity in response to the high tone itself, but increased activity in the frontal cortex in anticipation of the tone.

a. Increased responsiveness of primary auditory cortex neurons that respond to that tone.

What is the role of the hippocampus in the stress response? Choose the correct option. a. Suppresses the release of corticotropin-releasing hormone from the hypothalamus b. Stimulates the release of corticotropin-releasing hormone from the hypothalamus c. Releases corticotropin-releasing hormone into the portal circulation d. Releases adrenocorticotropic hormone into the bloodstream

a. Suppresses the release of corticotropin-releasing hormone from the hypothalamus

The cortical areas involved in attention are widespread. True or false? a. True b. False

a. True

Which of the following abnormalities in EEG voltage patterns is recorded synchronously across the entire brain during absence seizures? Choose the correct option. a. Very large amplitude waves b. Very small amplitude waves c. Irregular pattern d. Not rhythmic

a. Very large amplitude waves

In which areas did Penfield find that strong electrical stimulation resulted in arrested speech? Choose the correct option. a. Wernicke's area, the motor cortex, Broca's area, and the angular gyrus b. Only Wernicke's area and the angular gyrus c. Only the motor cortex and Broca's area d. Only Broca's area and Wernicke's area

a. Wernicke's area, the motor cortex, Broca's area, and the angular gyrus

Autism appears to be caused by a. abnormal properties of synapses/synapses not maturing correctly. b. abnormal growth of axons during development. c. side-effects of childhood vaccinations d. decreased neurogenesis in regions of frontal cortex e. expansion of certain brain areas, such as the frontal cortex

a. abnormal properties of synapses/synapses not maturing correctly.

The most commonly used drugs for treating depression work through which of the following mechanisms? a. block the reuptake of serotonin at synapses b. increase the release of serotonin at synapses c. increase the release of dopamine at synapses d. activate the NMDA receptor e. block the reuptake of dopamine at synapses

a. block the reuptake of serotonin at synapses

In associative learning studies of monkeys, dopaminergic neural activity in the ventral tegmental area of subjects that had been successfully conditioned to a stimulus (by pairing with prior juice rewards) showed a. decreased activity when the predicted reward was withheld. b. decreased activity when they were given a reward. c. increased activity when they were given a reward. d. decreased activity in response to the conditioned stimulus.

a. decreased activity when the predicted reward was withheld.

Functional neuroimaging and electrophysiological studies have provided evidence that selective attention to stimuli _______ responses. (you may choose more than one correct answer) a. facilitates more accurate b. facilitates quicker c. results in enhanced

a. facilitates more accurate b. facilitates quicker c. results in enhanced

How many synapses do you have in your cerebral cortex now (assuming you're about 20-25) compared to when you were five years old? a. fewer synapses b. approximately the same number c. more synapses d. Could be more or fewer synapses, depending on how intellectually active you have been

a. fewer synapses

Which of the following describes the EEG recording from an awake, active and thinking individual? a. high frequencies and low amplitude waves b. low frequency, high amplitude waves c. regular action potential spikes d. low frequency, low amplitude waves

a. high frequencies and low amplitude waves

When an embryonic limb bud removed, the number of motor neurons in the corresponding area of the spinal cord is markedly decreased. Why are fewer motor neurons present after limb bud removal? a. the same number of motor neurons are born, but more motor neurons die b. the motor neurons migrate to another area of the spinal cord where they may be needed c. since the target tissue is missing, the motor neurons are converted into local circuit neurons d. fewer motor neurons are born (less cell proliferation)

a. the same number of motor neurons are born, but more motor neurons die

Which of the following brain areas are most important for language-related memory, such as the meaning of words? a. upper left temporal lobe b. right inferior temporal lobe c. primary auditory cortex d. hippocampus

a. upper left temporal lobe

Which of the following would be the most effective site for self-stimulation for reward? a. ventral tegmental area b. hippocampus c. parietal cortex d. raphe nucleus e. temporal lobe

a. ventral tegmental area

Fetal alcohol syndrome results in symptoms very similar to those caused by L1 mutations, such as a decreased size of the corpus callosum (fewer axons crossing). Can you come up with a hypothesis that could explain this similarity?

alcohol inhibits adhesion between L1 molecules

Commissural neurons send out axons in the spinal cord that are attracted to the floorplate at the midline by diffusible Netrins. Once the axons cross the midline, they become insensitive to Netrin and sensitive to Slit, which is also in the floorplate. The reason for this is that when the axons cross the midline, something in the floorplate induces expression of a receptor called Robo. When Robo binds to Slit, it has a repulsive effect on the growth cone and inhibits the netrin receptor (DCC). For each of the following, predict how axon navigation would be altered (where would axons go)? Netrin not present Slit not present Robo is not expressed

axons would not be attracted to midline, so would either stay on ipsilateral side or grow randomly axons would stay attracted to midline netrin so wouldn't cross, but likely stay in center Same as with Slit, since Robo is receptor for Slit...

Commissural axons in the spinal cord are initially attracted towards the midline floorplate, and cross to the contralateral side. If they are initially attracted to the midline, why do they cross to the other side and stay there, rather than being attracted back again to the midline? a. The axons grow so fast that their momentum propels them past the location of the non-diffusible netrin in the floorplate, so after they pass they can't respond to netrin anymore. b. Axons lose their attraction to netrins once they cross the midline, and begin to be repelled by slit. c. Netrins in the floorplate attract axons, but netrins disappear once the axons reach the floorplate.

b. Axons lose their attraction to netrins once they cross the midline, and begin to be repelled by slit.

What is the role of agrin in synapse formation at the neuromuscular junction? a. Stimulates gene expression in the muscle cell so that acetylcholine receptors are expressed b. Binds to a MuSK receptor in the muscle cell membrane, which leads to clustering of acetylcholine receptors at that location c. Agrin binds to acetylcholine receptors in the presynaptic terminal causing them to form a cluster d. Turns on the synthesis of the neurotransmitter acetylcholine

b. Binds to a MuSK receptor in the muscle cell membrane, which leads to clustering of acetylcholine receptors at that location

Which of the following statements about competitive interactions during the innervation of the neuromuscular junction is false? a. Blocking action potentials with TTX prevents the reduction of polyneuronal innervation. b. Blocking acetylcholine receptors with curare leads to the loss of all synaptic inputs. c. Polyneuronal innervation can be visualized with stains that reveal the presynaptic terminal and postsynaptic receptors. d. Reduction of polyneuronal innervation does not result from active displacement of the "losing" input by the eventual "winner." e. The eventual mononeuronal innervation results from a "winner-take-all" process in which the losing input begins to lose strength, resulting in receptor loss and then further weakening.

b. Blocking acetylcholine receptors with curare leads to the loss of all synaptic inputs.

How is the Wada procedure used to demonstrate hemispheric lateralization for speech? Choose the correct option. a. Broca's area is anesthetized to see the impact on speech. b. Each hemisphere is anesthetized in turn to see the impact on speech. c. The corpus callosum is severed to see the impact on speech. d. Wernicke's area is anesthetized to see the impact on speech.

b. Each hemisphere is anesthetized in turn to see the impact on speech.

In the proposed neural circuit for learned fear, the state of the autonomic nervous system is altered by what neural connection? Choose the correct option. a. Cells in the basolateral region of the amygdala project to the central nucleus of the amygdala. b. Efferents from the central nucleus of the amygdala project to the hypothalamus. c. Sensory information is sent to the basolateral region of the amygdala. d. Cells in the basolateral nucleus of the amygdala project to the cerebral cortex.

b. Efferents from the central nucleus of the amygdala project to the hypothalamus.

Which of the following is the principal reason that neurons do not effectively regenerate their axons in the CNS? a. Loss of glutamate from damaged regions results in too little glutamate to support synaptic signaling. b. Inhibitory factors prevent axonal regeneration in the CNS. c. Damaged neural regions no longer express the neuroprotective caspase gene. d. Axons do not know in which direction they should regenerate. e. CNS neurons cannot regrow axons, no matter what the local conditions are.

b. Inhibitory factors prevent axonal regeneration in the CNS.

PET imaging during an experiment studying the effect of attending to specific features of a visual stimulus showed the greatest brain activity for moving stimuli occurred in which area of cortex? Choose the correct option. a. IT b. MT c. V4 d. Area 17

b. MT

Which of the following examples correctly explains how benzodiazepines and barbiturates work to suppress seizures? Choose the correct option. a. Mimic the withdrawal of chronic depressant drugs such as alcohol b. Prolong the inhibitory actions of GABA c. Block GABA receptors d. Increase the tendency to fire high-frequency action potentials

b. Prolong the inhibitory actions of GABA

What brain structure is known to act as a powerful pacemaker for the cerebral cortex? Choose the correct option. a. Midbrain b. Thalamus c. Brain stem d. Cerebellum

b. Thalamus

What happens to brain activity in the visual cortex when subjects are forced to attend to parts of the visual field outside the fovea? Choose the correct option. a. The whole retinotopic map becomes active in the visual cortex. b. The highest brain activity shifts retinotopically to striate areas corresponding to outside foveo areas. c. Visual areas outside the occipital cortex participate in this type of task. d. Activity in the primary visual cortex ceases and the extrastriate cortex takes over.

b. The highest brain activity shifts retinotopically to striate areas corresponding to outside foveo areas.

During development a muscle fiber is initially innervated by axons from three different motorneurons. Suppose that right after synapse formation you treat those motorneurons with tetrodotoxin. What would you guess would be the outcome? a. All the synapses on the muscle would be lost. b. The muscle fiber would remain innervated by all three motor neurons c. Only one of the three motor neurons would remain innervating the muscle fiber. d. Axons would sprout, and the muscle fiber would likely be innervated by additional motor neurons.

b. The muscle fiber would remain innervated by all three motor neurons

If a person with a neglect syndrome affecting the right hemisphere of the brain is asked to close her eyes and point toward the midline of her body, where will she point? Choose the correct option. a. To a part of her body on her dominant side b. Too far to the right of her body c. The midline of her body d. Too far to the left of her body

b. Too far to the right of her body

Which of the following is a common side effect of frontal lobotomy in a human? Choose the correct option. a. Profound memory loss b. Trouble concentrating c. Decreased IQ d. Increased anxiety

b. Trouble concentrating

What part of the embryo ends up becoming the brain? a. mesenchyme b. anterior neural tube c. neural crest d. medial endoderm e. anterior notochord

b. anterior neural tube

Cells from the neural crest make which of the following? a. dorsal spinal cord b. dorsal root ganglia c. amygdala d. cerebellum e. cerebral cortex

b. dorsal root ganglia

What determines the direction that growth cones travel? a. mechanical guidance, or the path of least resistance where there are gaps they can get through b. growth cones sense cues in their environment and respond to them c. the distance and direction is predetermined and unaffected by neighboring tissue d. radial glia

b. growth cones sense cues in their environment and respond to them

In which of the following instances would you normally expect to have regeneration of axons? (there may be more than one correct answer) a. rat motor neuron with cell body in spinal cord and damage to axon inside spinal cord b. human motor neuron with cell body in spinal cord and damage to axon outside spinal cord c. human DRG neuron with central root damage within spinal cord d. human descending corticospinal tract axon that has been crushed e. frog with severed optic nerve

b. human motor neuron with cell body in spinal cord and damage to axon outside spinal cord e. frog with severed optic nerve

This brain area is known to be important for assessing emotions in others, and psychopaths have reduced activity in this area: a. left parietal cortex b. medial frontal cortex c. hypothalamus d. ventral tegmentum e. striatum

b. medial frontal cortex

If the ventral half retina of a tadpole is replaced by the dorsal half retina of another tadpole (a transplant), the transplanted dorsal retina will send axons to a. the same location in the tectum as the original ventral retina. b. to the same location in the tectum as the existing dorsal retina. c. all over the tectum in a disordered, rather random manner. d. the opposite side of the brain as the removed ventral half

b. to the same location in the tectum as the existing dorsal retina.

Which of the following is strong evidence linking the amygdala with fear? Choose the correct option. a. Monkeys with bilateral amygdalectomy have diminished visual perception and poor visual recognition. b. Monkeys with bilateral amygdalectomy show sham rage. c. Bilateral amygdalectomy in animals profoundly reduces fear and aggression. d. Animals with the Klüver-Bucy syndrome exhibit flattened emotions.

c. Bilateral amygdalectomy in animals profoundly reduces fear and aggression.

Which of the following is central to the process of programmed cell death or apoptosis? Choose the correct option. a. Match between molecules on growing axons and those on their target cells b. Accidental cell death resulting from injury c. Competition for trophic factors d. Chemoattractants and chemorepellents

c. Competition for trophic factors

Injecting corticotropin-releasing hormone (CRH) into experimental animals can produce which of the following behavioral effects? Choose the correct option. a. Psychotic behaviors b. Hyperactivity c. Increased behavioral expression of anxiety d. Decreased fear response

c. Increased behavioral expression of anxiety

Define attention. Choose the correct option. a. An increased reaction time b. A state of hyperactivity and impulsiveness c. The ability to focus on one aspect of sensory input d. An increased detection threshold

c. The ability to focus on one aspect of sensory input

What is fasciculation? a. binding of growth cones to the extracellular matrix through integrin molecules b. attraction of axons and growth towards guidance cues c. axons stick to adjacent axons through cell adhesion molecules on their surface, forming bundles of axons d. the process of axon growth being inhibited by chemorepellents

c. axons stick to adjacent axons through cell adhesion molecules on their surface, forming bundles of axons

Individuals with bilateral damage to the amygdala show deficits in recognizing and feeling the emotion of a. sadness. b. anger. c. fear. d. disgust. e. all the above.

c. fear

In adult songbirds neurogenesis is known to occur on a seasonal basis. These newborn neurons a. arise from the neurons that undergo cell division. b. are essential for the ability to navigate during migration. c. form functional synapses and are involved in song learning. d. do not form functional synapses.

c. form functional synapses and are involved in song learning.

The growing tip of an axon is called a(n) a. endfoot b. neuroblast c. growth cone d. neurula e. integrin

c. growth cone

Which of the following parts of the limbic system are considered important for expressing emotions? (more than one answer) a. hippocampus b. lateral temporal lobe c. hypothalamus d. amygdala e. cingulate gyrus

c. hypothalamus d. amygdala e. cingulate gyrus

Which of the following would be a reliable way to determine the level of a person's autonomic fear response? a. observe freezing (stopping all movement) behavior b. experimenters watch facial changes in subjects c. skin conductance response d. ask subjects to rate fear on a 1 to 10 scale

c. skin conductance response

Commissural axons are those that cross from one side of the spinal cord to the other. You have already studied commissural neurons, but just haven't called them that. Name (or say what it does) one type of neuron that is a commissural neuron in the spinal cord.

corticospinal tract (brain stem...), secondary pain afferents, interneurons for motor system, etc., anything that crosses to other side

Which of the following statements explains why neurons that fire together wire together? Choose the correct option. a. A synapse formed by a presynaptic axon is weakened when the presynaptic axon is active at the same time that the postsynaptic neuron is strongly activated by other inputs. b. A synapse formed by a presynaptic axon is weakened when the presynaptic axon is active at the same time that the postsynaptic neuron is weakly activated by other inputs. c. A synapse formed by a presynaptic axon is strengthened when the presynaptic axon is active at the same time that the postsynaptic neuron is weakly activated by other inputs. d. A synapse formed by a presynaptic axon is strengthened when the presynaptic axon is active at the same time that the postsynaptic neuron is strongly activated by other inputs.

d. A synapse formed by a presynaptic axon is strengthened when the presynaptic axon is active at the same time that the postsynaptic neuron is strongly activated by other inputs.

Which of the following statements about neurogenesis is false? a. Cell division takes place in a structure called the ventricular zone. b. The latest born neurons in the cerebral cortex migrate past earlier born neurons into more superficial layers of the brain. c. Neurogenesis occurs at the inner margin of a hollow cylinder called the neural tube. d. After each cell division both daughter cells terminally differentiate, that is, they exit the cell cycle (stop dividing) and begin to develop a neuronal phenotype.

d. After each cell division both daughter cells terminally differentiate, that is, they exit the cell cycle (stop dividing) and begin to develop a neuronal phenotype.

Anxiety disorders have been related to which of the following? Choose the correct option. a. Hyperactivity of the amygdala b. Diminished activity of the hippocampus c. Elevated activity of the prefrontal cortex d. All choices are correct.

d. All choices are correct.

Adrenocorticotropic hormone (ACTH) is released by the anterior pituitary gland when what neurochemical is released by parvocellular neurosecretory neurons of the hypothalamus? Choose the correct option. a. Norepinephrine (NE) b. GABA c. Serotonin d. Corticotropin-releasing hormone (CRH)

d. Corticotropin-releasing hormone (CRH)

What part of the nervous system generates the fluctuations and oscillations that are measured by an EEG? a. Individual cortical neurons b. Individual thalamic neurons c. Axons of many thalamic neurons projecting to the cerebral cortex d. Dendrites of many pyramidal neurons in the cerebral cortex

d. Dendrites of many pyramidal neurons in the cerebral cortex

Which of the following describes the neglect syndrome observed after right posterior parietal lesions? Choose the correct option. a. Specific body parts on both sides are completely ignored. b. Specific individuals are completely ignored. c. Specific types of objects are completely ignored. d. Everything to one side of the center of gaze is completely ignored.

d. Everything to one side of the center of gaze is completely ignored.

Electrical stimulation of the amygdala elicits what response in humans? Choose the correct option. a. Increased recognition of fearful, happy, and neutral facial expressions b. Decreased vigilance or attention c. Decreased fear and aggression d. Increased anxiety and fear

d. Increased anxiety and fear

Where is the language area known as Wernicke's area located? Choose the correct option. a. Left frontal cortex near the primary motor area b. In the parietal occipital junction of the left hemisphere near the end of the Sylvian fissure c. In the left precentral gyrus d. Left superior surface of temporal lobe between the auditory cortex and the angular gyrus

d. Left superior surface of temporal lobe between the auditory cortex and the angular gyrus

During development, the survival of neurons is dependent on neurotrophins in target tissues. So why don't these neurons die after injury in the peripheral nervous system that separates the neurons from the target tissue? a. In adults the neurotrophins are present in all tissues, so survival isn't dependent on the target b. Adult neurons are no longer dependent upon neurotrophins c. Neurons can survive without neurotrophins for days, and within that time have regrown back to their targets. d. Regenerating Schwann cells in nerves release neurotrophins after nerve trauma

d. Regenerating Schwann cells in nerves release neurotrophins after nerve trauma

Which of the following best describes activity-dependent synaptic rearrangement? Choose the correct option. a. Almost all activity-dependent synaptic rearrangement occurs before birth as a consequence of spontaneous electrical activity in developing neurons. b. Actively migrating neural precursor cells are precisely guided to the cortical plate by the network of radial glial fibers. c. When retinal activity inhibits a postsynaptic LGN neuron, the synapses between them are lost. d. Significant activity-dependent shaping of neuron connections occurs after birth and is influenced profoundly by sensory experience.

d. Significant activity-dependent shaping of neuron connections occurs after birth and is influenced profoundly by sensory experience.

The EEG is primarily used to help diagnose certain neurological conditions, especially which of the following? Choose the correct option. a. Abnormal heart rhythms b. Brain tumors c. Schizophrenia d. The seizures of epilepsy

d. The seizures of epilepsy

You are testing a person who had their corpus callosum and anterior commissure severed (split brain patient) and have placed a familiar object, like an apple, their right hand while their eyes are closed. If you then ask them to identify the object, what is likely to happen? a. They will be able to feel it, but won't be able to name it. b. They will not be conscious of the apple in their hand and deny it is there. c. They will be unable to understand the question and therefore will not respond. d. They will be able to tell you it is an apple.

d. They will be able to tell you it is an apple. --somatic sensory information crosses to left side of brain in brain stem... Language area in left hemisphere also.

Which of the following is true about the ability of infants and children to acquire language? Choose the correct option. a. Babbling occurs around 2 months of age and leads to full sentences by 6 months. b. "Motherese" hinders children from learning correct speech sounds. c. Children tend to be confused about word boundaries. d. Three-month-old infants show brain activity in response to spoken words that is similar to that of adults.

d. Three-month-old infants show brain activity in response to spoken words that is similar to that of adults.

What does it mean when we say that there has been an increase in "synaptic strength"? a. Greater adhesion between pre- and post-synaptic cells by cadherins and other adhesion proteins. b. Greater number of synapses have been formed between two neurons. c. More neurotrophins are released and available for the presynaptic neuron. d. When a single action potential fires in the presynaptic neuron, a larger EPSP results in the post-synaptic neuron.

d. When a single action potential fires in the presynaptic neuron, a larger EPSP results in the post-synaptic neuron.

What does the Wernicke-Geschwind model propose as the role Broca's area plays in language processing? Choose the correct option. a. Broca's area controls the movement of lips, tongue, and larynx. b. Word-based signals are passed to Wernicke's area via the arcuate fasciculus. c. Broca's area processes sounds as meaningful words. d. Words are converted to a code for the muscular movements required for speech.

d. Words are converted to a code for the muscular movements required for speech.

Most generalized seizures are accompanied by rhythmic limb movements which are called __________ muscle activity. a. atonic b. oscillatory c. beta d. clonic e. tonic

d. clonic

Which of the following brain regions is most important for the regulation of pituitary hormone release and modulation of parasympathetic and sympathetic nervous system responses? a. tegmentum b. thalamus c. amygdala d. hypothalamus e. hippocampus

d. hypothalamus

During human development, if the posterior neural tube doesn't completely close, what will be the outcome for the child? a. anencephaly b. lissencephaly (minimal sulci or gyri) c. lack of cerebellum, but the rest of the brain relatively normal d. spina bifida e. development of second brain where tube didn't close f. enlarged brain

d. spina bifida

The most direct connections between the left and right cortex is via a. connections through the basal ganglia b. connections through the brain stem c. connections through the thalamus d. the corpus callosum

d. the corpus callosum

As evident by the studies of Paul Broca and Carl Wernicke, patients with damage to the ventroposterior region of left frontal cortex a. are able to produce words but have difficulty understanding language. b. lose the capacity to produce and understand specific categories of words (e.g., verbs). c. always show diverse motor deficits along with speech generation deficits. d. always show diverse sensory deficits along with receptive language deficits. e. can understand language but cannot produce organized speech.

e. can understand language but cannot produce organized speech.

Drugs of abuse, such as heroin and amphetamine, all seem to have what effect in common? They all: a. increase adrenalin levels in the bloodstream b. increase serotonin neurotransmission c. increase activity of substantia nigra neurons d. activate opiate receptors e. increase dopamine neurotransmission

e. increase dopamine neurotransmission

At what locations are newly born neurons found in adult primates? a. throughout the entire brain b. only in the cerebellum c. only in the cerebral cortex d. only in the spinal cord e. only in hippocampus and olfactory bulb

e. only in hippocampus and olfactory bulb

In the chapter "Eyes Right" in the book The Man Who Mistook his Wife for a Hat, Oliver Sacks describes a woman who had had a stroke. She denied the existence of her left arm (even though it still had normal reflexes), would only turn to the right, would often apply lipstick only to the right side of her mouth, and when the woman ate a piece of cake, she only ate the right side. Where do you think the brain damage from her stroke was?

right parietal association cortex