COGS1000 Questions

Which factor is important in determining the membrane potential when there are multiple permeant ions? Select one: 1.The concentration gradient of the individual ionic species 2.The permeability of the membrane to the individual ionic species 3.The sum total of all of the ions on both sides of the membrane 4.Both a and b 5.All of the above

4.Both a and b

A researcher conducts a voltage clamp experiment on a giant squid axon. She clamps a typical neuron at 0mV. Which graph represents the current changes she will observe. Select one: 1. A 2. B 3. C 4. D 5. E

A

An animal model is developed in which gamma motor neurons are dysfunctional. If you record the activity of the Ia fiber (spindle afferent), which pattern would you expect to see when the innervated muscle contracts? Select one: 1. A 2. B 3. C 4. D 5. E

A

Which observation was not observed in Hodgkin and colleagues' voltage-clamp study of squid action potentials? Select one: 1.Capacitive currents in response to hyperpolarizing voltage steps 2.Capacitive currents in response to depolarizing voltage steps 3.A transient inward current as a result of depolarization 4.A sustained outward current as a result of hyperpolarization 5.A delayed outward current as a result of depolarization

A sustained outward current as a result of hyperpolarization

You are watching a movie and having a snack when you accidentally drop some of your food, causing you to avert your gaze from the television across the room to your lap. What is one visual response that will occur? Select one: 1.Conjugate eye movements 2.Accommodation of the lens 3.Divergence of the eyes 4.Vestibulo-ocular movements 5.Ptosis

Accommodation of the lens

Which mechanism is not a component of the phototransduction signaling cascade initiated by light falling on a rod? Select one: 1.Absorption of a photon of light by 11-cis retinal 2.Activation of protein kinase A 3.A conformational change in the rhodopsin protein 4.Dissociation of the α subunit of transducin from the β/γ complex 5.Increased activity of PDE (phosphodiesterase)

Activation of protein kinase A

Which statement is a common, defining feature of membrane-bound active ion transporters? Select one: 1.All are electrogenic. 2.All transport two or more different ions. 3.All catalyze the conversion of ATP to ADP. 4.All are able to move at least one ion against its concentration gradient. 5.All move sodium across the membrane.

All are able to move at least one ion against its concentration gradient.

Age-related macular degeneration, or AMD, Select one: 1.is rising in incidence in the United States. 2.can be detected by means of the Amsler grid. 3.can result from gradual loss of the pigment epithelium (dry AMD). 4.can be treated by laser-induced phototoxicity (wet AMD). 5.All of the above

All of the above

Animal toxins have been discovered that Select one: 1.block sodium channels. 2.prolong the open state of sodium channels. 3.alter the voltage-dependence of sodium channels. 4.block potassium channels. 5.All of the above

All of the above

In the operation of sodium-potassium ATPase, Select one: 1.there is an obligatory coupling of sodium efflux and potassium influx. 2.this transporter (or "pump") is electrogenic. 3.phosphorylation and dephosphorylation respectively, are associated with the sodium and potassium transport steps. 4.the pump transports two potassium ions for every three sodium ions. 5.All of the above

All of the above

Retinal axons project to the Select one: 1.thalamus. 2.hypothalamus. 3.superior colliculus. 4.pretectum. 5.All of the above

All of the above

Vergence eye movements Select one: 1.depend on binocular disparity measurements made in neocortex. 2.are performed in conjunction with saccadic eye movements. 3.depend on vergence centers in the midbrain. 4.are driven by bursts of action potentials that drive either converging or diverging movements. 5.All of the above

All of the above

Which statement about the retina's operation across different levels of ambient light is true? Select one: 1.For a given level of ambient light, an ON-center ganglion cell responds proportionately to a small spot of light over an intensity range of about one log unit. 2.Via adaptational mechanisms, ON-center ganglion cells can dynamically encode brightness levels in their ON-center over a range of 6 log units of ambient light levels. 3.Ganglion cells generally do not report absolute light intensities, but rather encode relative intensity differences between center and surround. 4.Interactions within the inner plexiform layer play an important role in modulating the photic sensitivity of ganglion cells. 5.All of the above

All of the above

Which structure is not involved in the generation of smooth pursuit eye movements? Select one: 1.The superior colliculus 2.The PPRF 3.The frontal eye fields 4.Area MT 5.All of the structures above are involved in the generation of smooth pursuit eye movements.

All of the structures above are involved in the generation of smooth pursuit eye movements.

Which statement does not stem from the application of Ohm's law to ionic conductances? Select one: 1.The driving force on the ionic current is the difference between the membrane potential and the ion's Nernst potential. 2.The conductance for an ion is inversely proportional to the resistance of the membrane to the passage of that ion. 3.All permeant ions experience an identical driving force at each time point during the course of an action potential. 4.The conductance for each ion can be calculated based on the measured ionic currents and the calculated driving force. 5.The calculations stemming from Ohm's law can be used to derive a mathematical description of the action potential.

All permeant ions experience an identical driving force at each time point during the course of an action potential.

During the patellar reflex, you measure voltage change in the flexor muscle motor neuron cell body in the ventral horn of the spinal cord. After stimulation of the stretch receptors, which of the following would you observe? Select one: 1.An EPSP 2.An action potential 3.An IPSP 4.No change in voltage 5.Constant action potential firing leading to fused tetanus in the flexor muscle

An IPSP

Which statement best describes the action potential? Select one: 1.An action potential is specialized to transmit signals over only very short distances. 2.An action potential is a brief change in membrane potential from positive to negative. 3.An action potential is elicited by hyperpolarization. 4.An action potential occurs when the cell's membrane potential reaches threshold. 5.The level of depolarization is graded in proportion to the magnitude of the stimulus.

An action potential occurs when the cell's membrane potential reaches threshold.

Which of the following is not integral to the action potential waveform? Select one: 1.A change in permeability of the membrane to sodium 2.A change in permeability of the membrane to potassium 3.A transient increase in the sodium current 4.An initial decrease in the potassium current 5.A "self-activating" aspect to the rise in the sodium current

An initial decrease in the potassium current

Which method helped scientists correct a long-standing misconception about the neurological origins of facial weakness deficits seen in humans? Select one: 1.fMRI, or functional magnetic resonance imaging 2.Anatomical tract-tracing in primates 3.High-resolution EEG 4.Optical imaging of neuronal activation patterns in the cortex 5.PET scans

Anatomical tract-tracing in primates

Refer to the figure. A patient recovering from a car accident discovers that she can no longer voluntarily direct her gaze away from a stimulus in her visual field (she cannot perform an anti-saccade). The patient most likely has sustained damage in which location shown in the figure? Select one: 1. A 2. B 3. C 4. D 5. E

B

Which statement about color vision is false? Select one: 1.Because there are several different color types of cones, they are more sensitive to low (dim) illumination levels than the population of rods is. 2.Cones (in humans) come in three different "colors": blue, green, and red (or short-, medium-, and long-wavelength). 3.Different wavelengths of light produce different patterns of activity in the cone population as a whole. 4.Information from specific color cones can be selectively relayed to specific regions of a retinal ganglion cell's receptive field. 5.The different photopigments in each cone are highly sensitive to a small range of wavelengths but can actually be activated by photons of a wide range of wavelengths.

Because there are several different color types of cones, they are more sensitive to low (dim) illumination levels than the population of rods is.

Which is not a feature of motor unit plasticity? Select one: 1.Changes in the strength and endurance of individual muscle fibers 2.Changes in the firing properties of motor neurons 3.Changes in the size and location of motor pools 4.Changes in muscle properties in response to the type of motor neurons innervating the muscle 5.Capacity for a non-exercised arm to be influenced by unilateral training of the other arm

Changes in the size and location of motor pools

Which statement about the language capacities of humans and non-humans is true? Select one: 1.Only humans have the ability to understand symbols and communicate information. 2.Honeybees have the ability to learn many different symbols and to change their behavior in response to retraining. 3.Chimps in captivity have learned hundreds of symbols and are able to use them in a manner comparable to the speech of adult humans. 4.Chimps in the wild communicate by means of gestures, facial expressions, and the manipulation of objects. 5.Primates use their left hemisphere to perceive affective tone in intraspecies communications.

Chimps in the wild communicate by means of gestures, facial expressions, and the manipulation of objects.

What would occur if the ATPase pumps in a neuron stopped functioning? Select one: 1.Concentration gradients would not be maintained across the membrane 2.At rest, sodium would continuously depolarize the cell 3.At rest, potassium would continuously depolarize the cell 4.During the action potential, the sodium channel would not inactivate 5.During the action potential, the voltage-gated ion channels would remain closed

Concentration gradients would not be maintained across the membrane

Which statement about language is false? Select one: 1.Failure to develop language during childhood results in severe, lifelong linguistic deficits. 2.Language depends on specialized areas of the temporal and frontal lobes. 3.The left hemisphere usually plays a dominant role in semantic processing. 4.The right hemisphere usually governs emotional or affective aspects of language. 5.Cortical areas used in sign language are largely different from those used in spoken language.

Cortical areas used in sign language are largely different from those used in spoken language.

A patient is having difficulty sitting and standing without support. If you know this is due to a spinal cord injury, in which location would you expect the damage to be? Select one: 1. A 2. B 3. C 4. D 5. E

D

Which figure best illustrates the control of attention by the two hemispheres? Select one: 1. A 2. B 3. C 4. D 5. E

D

A patient is having trouble abducting their left eye (moving the eye in a direction away from the nose). What nervous system damage would you expect to find from diagnostic tests? Select one: 1.Damage to the left cranial nerve III 2.Damage to the left cranial nerve IV 3.Damage to the left cranial nerve VI 4.Damage to the right cranial nerve IV 5.Damage to the right cranial nerve VI

Damage to the left cranial nerve VI

For which task would near and far cells help the viewer extract relevant information? Select one: 1.Deciphering a random dot stereogram 2.A color blindness test 3.Compensating for near-sightedness and far-sightedness 4.Perceiving color as objects moved closer 5.Rapidly detecting objects moving in the visual periphery

Deciphering a random dot stereogram

Which symptom would you expect an individual with a right parietal lobe lesion to exhibit? Select one: 1.Deficit in attention to the right side of the body or space 2.The perception of two sensory systems together (e.g., seeing colors when hearing music) 3.Deficit in recognizing faces 4.Deficit in attention to the left side of the body or space 5.Diminished success during Wisconsin card sorting task

Deficit in attention to the left side of the body or space

Which symptoms would you expect a patient with a right temporal lobe lesion to exhibit? Select one: 1.Deficit in attention to the left side of the body or space 2.Deficit in recognizing faces 3.Deficit in attention to the right side of the body or space 4.The perception of two sensory systems together (e.g., seeing colors when hearing music) 5.Diminished or abolished success during the delayed response task

Deficit in recognizing faces

Which statement about extrastriate areas is false? Select one: 1.One "stream" of information helps the viewer detect fine details of structures and aids in object recognition. 2.One "stream" of information helps the viewer detect and analyze motion. 3.The dorsal stream is thought to be important for understanding positional relationships between objects. 4.Deficits in the ventral stream often give rise to visual deficits such as an inability to perceive the motion of objects. 5.Information from parvocellular and magnocellular LGN contribute to both the dorsal and ventral streams.

Deficits in the ventral stream often give rise to visual deficits such as an inability to perceive the motion of objects.

What symptom would you expect bilateral lesions to the dorsolateral prefrontal cortex to produce in a monkey? Select one: 1.Delayed or abolished success during the delayed response task 2.Inability to recognize faces 3.Deficit in attention to the body 4.The perception of two sensory systems together (e.g., seeing colors when hearing music) 5.Deficit in attention paid to extrapersonal space

Delayed or abolished success during the delayed response task

Which of the following was observed in studies measuring the efflux of radioactive sodium from the squid giant axon? Select one: 1.Dramatic increase of efflux during a brief train of action potentials 2.Sharp drop in efflux when intracellular potassium was removed 3.Dependence of efflux upon the presence of ATP 4.Decrease of efflux when ATP synthesis was increased 5.No recovery when potassium or ATP was restored.

Dependence of efflux upon the presence of ATP

You measure changes in membrane potential in an ON-center bipolar cell that is exposed to light in the center of its receptive field. What response would you expect to see? Select one: 1.An action potential 2.Depolarization due to increased release of glutamate by the photoreceptor cell 3.Hyperpolarization due to decreased release of glutamate by the photoreceptor cell 4.Hyperpolarization due to increased release of glutamate by the photoreceptor cell 5.Depolarization due to decreased release of glutamate by the photoreceptor cell

Depolarization due to decreased release of glutamate by the photoreceptor cell

A seven-year-old boy is having trouble learning to read at school. He undergoes some cognitive tests and an fMRI scan. The scan shows decreased activity in the left occipito-temporal sulcus compared to other children his age. Which disorder do these results implicate? Select one: 1.Broca's aphasia 2.Wernicke's aphasia 3.Alexias 4.Dyslexia 5.Dysarthria

Dyslexia

Which statement about the primary visual cortex is false? Select one: 1.Each of the six layers has distinct cell types that send projections both within cortical columns and to structures outside of cortex. 2.Pyramidal cells are the principal projection neurons of visual cortex. 3.Layer 4C is dominated by spiny stellate cells. 4.The upper layers (layers 2 and 3) project to layer 5. 5.The lower layers (layers 5 and 6) project to the brainstem and thalamus.

Each of the six layers has distinct cell types that send projections both within cortical columns and to structures outside of cortex.

Why is myopia in humans thought to be more common now than it was in ancient times? Select one: 1.The vigorous exercise associated with early human lifestyles better nourished the retina. 2.Early humans were not exposed to the environmental toxins present in modern life. 3.Chronic exposure to fire smoke had a protective effect on the vision of early humans. 4.Early humans did not engage in the kinds of activities (e.g., reading and writing from an early age, watching television) characteristic of modern life. 5.Myopia was not less common; it was less recognized.

Early humans did not engage in the kinds of activities (e.g., reading and writing from an early age, watching television) characteristic of modern life.

Which statement regarding membrane potential and equilibrium potential is true? Select one: 1.Membrane potential is affected by ion concentration in- and outside of the cell; equilibrium potential is affected only by ions inside the cell. 2.Equilibrium potential is affected by the concentration and electrical gradients of one ion; membrane potential is affected by gradients of all ions. 3.Both membrane and equilibrium potentials change during an action potential. 4.Equilibrium potentials are affected by membrane permeability; membrane potentials are not. 5.Equilibrium potentials are the same for all neurons; membrane potentials can be different depending on the neuron.

Equilibrium potential is affected by the concentration and electrical gradients of one ion; membrane potential is affected by gradients of all ions.

Which brain region(s) is(are) thought to be most important for vergence eye movements? Select one: 1.Frontal eye fields 2.Ventral visual stream in the temporal lobe 3.Extrastriate occipital regions 4.Superior colliculus 5.Medial and lateral vestibular nuclei

Extrastriate occipital regions

Which statement about the transformation from retinotopic coordinates to oculomotor commands is true? Select one: 1.Eye movements are determined solely by the specific oculomotor neurons that are activated. 2.Eye movements are determined solely by the total number of activated oculomotor neurons. 3.Eye movements are determined by the particular oculomotor neurons that are active and their firing rates. 4.Oculomotor neurons fire in rhythmic bursts until the correct eye position is obtained. 5.Oculomotor neurons have a high basal firing rate, and movement is based on inhibition of the neurons.

Eye movements are determined by the particular oculomotor neurons that are active and their firing rates.

Which symptom would you expect to see in a patient with lower motor neuron damage? Select one: 1.Hyperactive deep reflexes 2.Increased muscle tone 3.Babinski's sign 4.No development of atrophy 5.Hypoactive deep reflexes

Hypoactive deep reflexes

Which statement best describes the electrical properties of nerve cells? Select one: 1.They are exceptionally good conductors of electricity (much better than copper wires). 2.They are similar in their electrical conduction properties to copper wires. 3.In comparison to copper wires, they are relatively poor conductors of electricity. correct! 4.They are unable to conduct electricity under any circumstances. 5.They are electron sinks; they absorb many electrons, but no electricity comes out of them.

In comparison to copper wires, they are relatively poor conductors of electricity.

Which statement about the ionic permeability of cell membranes is true? Select one: 1.In resting nerve cells, the membrane is permeable to all ions. 2.The permeability of ions is constant over time. 3.In resting nerve cells, the membrane is quite permeable to potassium. 4.In resting nerve cells, the membrane is quite permeable to sodium. 5.In resting nerve cells, the membrane is quite permeable to calcium.

In resting nerve cells, the membrane is quite permeable to potassium.

A patient is experiencing double vision. A medical exam reveals that she can successfully gaze to the left (without head movement), but when asked to gaze forward or to the right, only the right eye moves as directed. Where is the doctor most likely to find neurological damage in this patient? Select one: 1.In the left oculomotor nerve 2.In the right oculomotor nerve 3.In the left abducens nerve 4.In the right abducens nerve 5.In the right trochlear nerve

In the left oculomotor nerve

Proper functioning of the lamprey central pattern generator (CPG) is dependent on which input? Select one: 1.Descending inputs from the brainstem or cortex 2.Excitatory interneurons that cross the midline 3.Inhibitory interneurons that cross the midline 4.Inhibitory interneurons that do not cross the midline 5.Motor neurons that cross the midline

Inhibitory interneurons that cross the midline

Which statement about the Babinski sign (or reflex) is false? Select one: 1.It involves the corticospinal tract. 2.The reflex changes between infancy and later development. 3.It is considered an upper motor neuron deficit. 4.It concerns normal versus abnormal flexion of the fingers. 5.It can be affected by stroke, trauma, and other neurological problems.

It concerns normal versus abnormal flexion of the fingers.

Which statement about cat locomotion is false? Select one: 1.Flexors play an important role during the swing phase. 2.Extensors play an important role during the stance phase. 3.It is controlled by a single spinal central pattern generator (CPG) that always produces left-right alternation within a segment. 4.Some gaits alternate activity between the left and right legs. 5.Some gaits involve synchronous use of forelimbs and hindlimbs.

It is controlled by a single spinal central pattern generator (CPG) that always produces left-right alternation within a segment.

Which statement about electrochemical equilibrium is true? Select one: 1.It involves the movement of a relatively large number of ions, altering the concentrations of permeant ions. 2.It occurs when the potential across the membrane exactly offsets the concentration gradient. 3.The size of the potential is inversely proportional to the size of the ion gradient. 4.The fluxes of ion that are required to generate the membrane potential disrupt chemical electroneutrality. 5.For a given ion concentration gradient, the resulting potential is independent of the number of charges on the ion.

It occurs when the potential across the membrane exactly offsets the concentration gradient.

Which statement about the withdrawal reflex is false? Select one: 1.It can be initiated by pain- and temperature-sensitive sensory fibers. 2.It has opposing effects within a limb. 3.It has opposing effects in the left and right limbs. 4.It controls muscles by means of polysynaptic pathways. 5.It results in extensor muscle activation within the stimulated limb.

It results in extensor muscle activation within the stimulated limb.

Which statement about the reticular activating system is true? Select one: 1.Its only essential role is the multimodal integration of sensory information. 2.It plays a direct role in the activation of all somatic motor neurons. 3.It plays a direct role in the activation of all visceral motor neurons. 4.It supports transitions between sleep and wakefulness. 5.It plays a direct role in the suppression of all somatic motor neurons.

It supports transitions between sleep and wakefulness.

Which statement about multiple sclerosis (MS) is false? Select one: 1.It is characterized by demyelination of axons along with some axon loss. 2.It was recently proven that all cases of MS are due to persistent infection by a tropical parasite. 3.Cases of MS vary considerably in terms of severity and progression of the illness. 4.Symptoms of MS may include weakness, paralysis, double vision, monocular blindness, and abnormal somatic sensations. 5.Magnetic resonance imaging can help diagnose some cases of MS.

It was recently proven that all cases of MS are due to persistent infection by a tropical parasite.

The method of clinically assessing language lateralization in humans by anesthetizing one hemisphere was devised by Select one: 1.Paul Broca. 2.Carl Wernicke. 3.Roger Sperry. 4.John Wada. 5.Norman Geschwind.

John Wada.

If you could knock out a gene that is expressed only in stellate neurons, which neocortical layer would be most affected? Select one: 1.Layer 1 2.Layer 2 3.Layer 4 4.Layer 5 5.Layer 6

Layer 4

In which structure would a visuotopically organized, alternating (left/right) pattern of monocular responsiveness be found? Select one: 1.Layers 2 and 3 of LGN 2.Layer 4 of LGN 3.Layer 2/3 of visual cortex 4.Layer 4 of visual cortex 5.All layers of visual cortex

Layer 4 of visual cortex

Healthy controls and patients with dyslexia are asked to read a paragraph while being scanned by fMRI. Where would you expect to see functional differences between the two groups during this task? Select one: 1.Left occipito-temporal sulcus 2.Broca's area 3.Wernicke's area 4.Left orbitofrontal cortex 5.Right temporal lobe

Left occipito-temporal sulcus

A patient is diagnosed with a tumor located in the right internal capsule. Which motor dysfunction would you expect to see in this patient? Select one: 1.Left side paralysis (or severe weakness) of the lower face 2.Right side paralysis (or severe weakness) of the lower face 3.Left side paralysis (or severe weakness) of the full face 4.Right side paralysis (or severe weakness) of the full face 5.Left side paralysis (or severe weakness) of the upper face

Left side paralysis (or severe weakness) of the lower face

Which statement about center-surround receptive fields in the retina is false? Select one: 1.Cells that are inhibited by light in their center are excited by light in their surround. 2.Cells that are excited by light in their center are inhibited by light in their surround. 3.The surround portion of the receptive field is typically an annulus (or doughnut-shaped ring) that surrounds the circular center. 4.Light in the center of an off-center cell will increase its firing rate. 5.The best stimulus for an on-center cell is light in its center and darkness in its surround.

Light in the center of an off-center cell will increase its firing rate.

Upper motor neurons involved in the control of axial muscles would most likely project to the spinal cord in which pattern? Select one: 1.Lateral gray matter over many spinal segments 2.Lateral gray matter over just a few spinal segments 3.Medial gray matter over many spinal segments 4.Medial gray matter over just a few spinal segments 5.Equal proportions to both lateral and medial gray matter

Medial gray matter over many spinal segments

In which brain region would you expect to find very large, motion-sensitive cells that respond selectively to oriented moving edges, while lacking responsiveness to fine structural details? Select one: 1.Parvocellular LGN 2.Area 17 3.V4 4.Peristriate cortex 5.Middle temporal area (MT)

Middle temporal area (MT)

Which statement about myelination is false? Select one: 1.Myelin sheaths are created by glial cells. 2.Myelin serves to sharply increase the time constant of the axon. 3.Multiple layers of closely opposed glial membranes wrap the axon and serve as an electrical insulator. 4.Myelin is absent at the nodes of Ranvier. 5.Sodium and potassium channels are clustered at the nodes of Ranvier.

Myelin serves to sharply increase the time constant of the axon.

Which statement about voltage-gated ion channels is true? Select one: 1.Without sodium channels, no current flows out 2.Without potassium channels, no current flows in 3.Na+ channels open after a short delay 4.K+ channels close after a short delay 5. Na+ and K+ channels can work independently of one another

Na+ and K+ channels can work independently of one another

The strictly monocular portion of the visual field is represented exclusively by which region of the retina? Select one: 1.Superior 2.Inferior 3.Nasal 4.Temporal 5.Fovea

Nasal

A friend has taken a job in a neuroscience research lab, and is studying neurons in a freshwater snail. He has been told to calculate the equilibrium potential of K+. Which equation will he use and what other information will he need? Select one: 1.Nernst equation; concentration of K+ inside and outside of the cell 2.Nernst equation; concentration of K+ inside and outside of the cell and permeability of K+ 3.Goldman equation; concentration of K+ inside and outside of the cell 4.Goldman equation; concentration of K+ inside and outside of the cell and permeability of K+ 5.Nernst equation; concentration of K+, Na+, and Cl- inside and outside of the cell

Nernst equation; concentration of K+ inside and outside of the cell

Which statement about the localization of language functions in human neocortex is false? Select one: 1.Neurons have been found that respond preferentially to a single, specific word. 2.Electrical stimulation at many different cortical locations interferes with language functions. 3.The specific pattern of "effective stimulus locations" varies significantly from one person to the next. 4.In bilingual people, words with the same meaning from two different languages may be stored in different cortical locations. 5.PET imaging experiments have shown that large regions of the left hemisphere are active in word recognition and production.

Neurons have been found that respond preferentially to a single, specific word.

What is the major determinant of the permeability of a membrane to a specific ion? Select one: 1.Size of the ion 2.Concentration of the ion inside the cell 3.Concentration of the ion outside the cell 4.Electrical charge of the ion 5.Number of open ion channels specific for that ion

Number of open ion channels specific for that ion

In which way do potassium channels in the squid giant axon differ from sodium channels? Select one: 1.The potassium channels pass only a few ions per second. 2.The potassium channels show little voltage dependence. 3.The summing of the individual potassium channels does not reconstruct the macroscopic current. 4.Once the potassium channels open in response to a voltage step command, they tend to remain open. 5.The potassium channels open in response to hyperpolarization of the membrane.

Once the potassium channels open in response to a voltage step command, they tend to remain open.

Which sequence represents the most direct pathway for the transmission of visual information from the eye to the brain? Select one: 1.Photoreceptor → bipolar cell → ganglion cell → brain 2.Horizontal cell → bipolar cell → ganglion cell → brain 3.Photoreceptor → bipolar cell → amacrine cell → brain 4.Photoreceptor → horizontal cell → ganglion cell →brain 5.Photoreceptor → bipolar cell → amacrine cell → ganglion cell → brain

Photoreceptor → bipolar cell → ganglion cell → brain

The figure shows the results of an experiment in which an animal is presented with visual stimuli, and recordings are taken simultaneously from the CNS. Given the stimuli and the observed recordings, where must the activated neurons be located? Select one: 1. Lateral geniculate nucleus of the thalamus 2. Optic tract 3. Primary visual cortex 4. Fusiform gyrus 5. Retinal ganglion cell

Primary visual cortex

Which of the following is not one of the five basic types of eye movements? Select one: 1.Saccades 2.Vergence 3.Ptosis 4.Optokinetic 5.Vestibulo-ocular

Ptosis

A patient complains of inability to move his right eye toward his nose and a drooping right eyelid. What other symptom would you expect to find upon examination? Select one: 1.Pupillary constriction in right eye 2.Pupillary dilation in right eye 3.Pupillary constriction in left eye 4.Inability to perform anti-saccade in left eye 5.Difficulty moving right eye away from nose

Pupillary dilation in right eye

Which feature is not a characteristic of certain primary visual cortex neurons? Select one: 1.Sensitivity to edges 2.Preference for a specific orientation 3.Rate of change in contrast 4.Preference for a specific direction of motion 5.Recognition of faces

Recognition of faces

Which treatment was shown to eliminate the early inward current in squid giant axons? Select one: 1.Removal of external sodium 2.Doubling of external sodium 3.Removal of external potassium 4.Doubling of external potassium 5.Removal of all external cations

Removal of external sodium

A teacher at a local school feels frustrated whenever the seasons change because her students begin wearing different shoes to school. This troubles her because she usually identifies her students by their footwear, and without that clue, she must wait for each student to talk before she knows who they are. Considering her symptoms, where would you expect to find damage in her nervous system? Select one: 1.Right lateral surface of the temporal lobe 2.Right posterior parietal cortex 3.Left ventromedial prefrontal cortex 4.Bilateral dorsolateral prefrontal cortex 5.Right fusiform gyrus

Right fusiform gyrus

Contralateral neglect syndrome arises from damage in which location? Select one: 1.Left posterior parietal cortex 2.Right fusiform gyrus 3.Left dorsolateral prefrontal cortex 4.Right posterior parietal cortex 5.Bilateral ventromedial prefrontal cortex

Right posterior parietal cortex

Which statement about human handedness is false? Select one: 1.About 90 percent of humans are right-handed, independent of culture. 2.Evidence indicates that our ancestors, into antiquity, were predominantly right-handed. 3.Right-handed people tend to have significantly better language skills than left-handed people. 4.Currently there are surprisingly few left-handers among the elderly. 5.Handedness is usually assessed by asking individuals about their preferences.

Right-handed people tend to have significantly better language skills than left-handed people.

By which mechanism are rod signals transmitted in conditions of low light? Select one: 1.Rod bipolar cells synapse on amacrine cells, which in turn synapse on cone bipolar cells. 2.Rod bipolar cells synapse on off-center ganglion cells that then transmit the rod signals to other ganglion cells. 3.Rod bipolar cells of both on and off types send outputs selectively to on- and off-center ganglion cells. 4.Rod photoreceptors send their outputs directly to melanopsin-containing ganglion cells. 5.Rod photoreceptors send their signals mainly through horizontal cells to the rod bipolar cells.

Rod bipolar cells synapse on amacrine cells, which in turn synapse on cone bipolar cells.

During a medical exam, a patient presents with eye movement task dysfunctions. Specifically, smooth pursuit movements are jerky, with more errors and irregularities than average. During a free-viewing test, visual sampling of a scene is less robust than average, viewing only a small portion of the image. Finally, the patient has difficulty remaining fixated on a target object. What disorder might these test results indicate? Select one: 1.Alzheimer's disease 2.Schizophrenia 3.Parkinson's disease 4.Huntington's disease 5.Myasthenia gravis

Schizophrenia

Which of the following is not necessary for neurons to communicate electrically? Select one: 1.Consumption of metabolic energy 2.Use of active transporters to create ionic gradients 3.Separation of large amounts of electrical charge, with excess positive charges stored inside the cell 4.Selective permeability of the cell membrane via different kinds of ion channels 5.Changes in membrane potential caused by the movement of ions across the cell membrane

Separation of large amounts of electrical charge, with excess positive charges stored inside the cell

Refer to the figure. What type of eye movement occurs after 0.5 seconds? Select one: 1. Smooth pursuit 2. Optokinetic 3. Saccades 4. Vergence 5. Vestibulo-ocular

Smooth pursuit

Which statement about ionic distributions in nerve cells is true? Select one: 1.Potassium is higher outside cells than inside cells. 2.Sodium is higher outside cells than inside cells. 3.Chloride is higher inside cells than outside cells. 4.Calcium is higher inside cells than outside cells. 5.The concentrations of all ionic species are the same for all nerve cells in all animals.

Sodium is higher outside cells than inside cells.

A researcher conducts a voltage clamp experiment on a giant squid axon and collects the data shown in the graph. At what membrane potential was the cell clamped? Select one: 1. 0 mV 2. Sodium's equilibrium potential 3. -65 mV 4. Potassium's equilibrium potential 5. -110 mV

Sodium's equilibrium potential

What is the function structure C? Select one: 1. Speeds up conduction of an action potential 2. Location of protein synthesis and cellular machinery 3. Receives incoming signals from other neurons 4. Regulates chemical environment for signaling 5. Regeneration of action potential

Speeds up conduction of an action potential

Which statement about the directional control of saccadic eye movements is true? Select one: 1.Several distant sites within the superior colliculus must be co-activated to produce eye movements in certain directions. 2.Stimulation of particular upper motor neurons in the superior colliculus always produces a movement to the same point in visuotopic space. 3.Stimulation of particular upper motor neurons in the superior colliculus always produces a movement of the same magnitude and direction. 4.Retinal afferents from each visuotopic location project to all regions of the superior colliculus so that each region can be foveated from any starting eye position. 5.Saccades to an oblique direction are produced by staircase-like eye movements.

Stimulation of particular upper motor neurons in the superior colliculus always produces a movement of the same magnitude and direction.

Where will voltage-gated Na+ channels be most abundant? Select one: 1. Structure A 2. Structure B 3. Structure C 4. Structure D 5. Structure E

Structure D

Which statement about language in people who are deaf is false? Select one: 1.Lesions of Wernicke's and Broca's areas produce deficits analogous to those caused by these lesions in hearing people. 2.Lesions of the right hemisphere affect the emotional tone of signing. 3.People who are deaf show lateralization of function similar to that of hearing people. 4.The offspring of deaf parents exhibit "babbling" in sign language that is analogous to the verbal babbling of children in hearing families. 5.Studies of congenitally deaf individuals indicate that Broca's area is specific to spoken language, whereas a region in the anterior temporal lobe is specific for visual and signed communication.

Studies of congenitally deaf individuals indicate that Broca's area is specific to spoken language, whereas a region in the anterior temporal lobe is specific for visual and signed communication.

If output from neocortical layer 6 is blocked, which structure would lose significant input? Select one: 1.Superior colliculus 2.Striatum 3.Brainstem modulatory systems 4.Cerebellum 5.Thalamus

Thalamus

What would happen if the membrane became permeable to the Y+ ions? Select one: 1. The Y+ ions would move into the bottom chamber, down their concentration gradient. 2. The Y+ ions would move into the bottom chamber, down their electrical gradient. 3. The Y+ ions would move into the top chamber, down their concentration gradient. 4. The Y+ ions would move into the top chamber, down their electrical gradient. 5. The Y+ ions would not move.

The Y+ ions would move into the top chamber, down their concentration gradient.

Which statement describes one of the features of Hodgkin and Huxley's mathematical model? Select one: 1.The action potential can be reconstructed based entirely on the time course and amplitudes of the ionic conductances. 2.The fast-rising phase can be accounted for by selective potassium entry. 3.The model is unable to mimic the experimentally measured refractory period. 4.The falling phase can be at least partially accounted for by the inactivation of the potassium current. 5.The undershoot can be accounted for by the time course of sodium current reactivation.

The action potential can be reconstructed based entirely on the time course and amplitudes of the ionic conductances

Which statement about sensorimotor integration in the superior colliculus (SC) is false? Select one: 1.Retinal activity always causes activation of cells in the upper layers of the SC. 2.The activation of neurons in the upper layers of the SC results in offset activation of lower-SC layers, producing a checkerboard pattern of upper-to-lower layer signaling. 3.Activity in the superficial, visual layer of the SC is not necessary for a saccade to occur. 4.Activity in the superficial, visual layer of the SC is not sufficient for a saccade to occur. 5.Saccades can occur in the dark.

The activation of neurons in the upper layers of the SC results in offset activation of lower-SC layers, producing a checkerboard pattern of upper-to-lower layer signaling.

Which statement about the lateral geniculate nuclei is false? Select one: 1.Each lateral geniculate nucleus receives light from both the left and right eyes. 2.The alternating layers represent alternate color sensitivities (i.e., blue-green-blue-green). 3.They are organized into six principal layers. 4.The four parvocellular layers have small cells. 5.The two magnocellular layers have large cells.

The alternating layers represent alternate color sensitivities (i.e., blue-green-blue-green).

Which statement about the cellular structure of the cerebral cortex is true? Select one: 1.Neocortex, found in all four lobes, contains three to six cellular layers. 2.The cytoarchitecture in the all association cortices appears histologically the same. 3.The archicortex includes the hippocampus. 4.The primitive paleocortex is found only in non-human primates. 5.The functions of 6-layered cortex are demonstrably more efficient than those in 3-layered cortex.

The archicortex includes the hippocampus.

Which ligand-gated ion channel is regulated primarily by an intracellular signal? Select one: 1.Glutamate receptor 2.The potassium-activated calcium channel 3.The glutamate receptor 4.The cAMP- and cGMP-gated ion channels 5.The acid-sensing ion channels

The cAMP- and cGMP-gated ion channels

A neuron has received enough stimulation to fire an action potential; it also has been treated with TEA, a K+ channel blocker. Which outcome is possible? Select one: 1.The cell will initially depolarize, but repolarization will take much longer because it relies only on ion pumps. 2.The cell will initially depolarize and will continue to do so until the cell reaches the equilibrium potential for Na+. 3.The cell will initially hyperpolarize and will return to resting membrane potential after a delay. 4.There will be no change in membrane potential in the cell. 5.There will be no change in membrane potential in the cell initially, but will it depolarize after a delay.

The cell will initially depolarize, but repolarization will take much longer because it relies only on ion pumps.

Which statement on the rising or overshoot phase of the action potential is true? Select one: 1.The time from threshold to maximum depolarization is essentially instantaneous (i.e., too fast to be measured accurately with current electronics). 2.A negative feedback loop leads to a regenerative depolarization that would increase continuously if unchecked. 3.The degree of depolarization is limited in part by the declining driving force on potassium entry. 4.The degree of depolarization is limited in part by the inactivation time course for the sodium current. 5.The degree of depolarization is limited in part by the inactivation time course of the potassium current.

The degree of depolarization is limited in part by the inactivation time course for the sodium current.

Which statement about the distributions of rods and cones is true? Select one: 1.Because cones carry three different color channels, there are three times as many cones as rods. 2.Rods outnumber cones by 100 to 1, which explains the greater sensitivity of rods in low light. 3.Rods are evenly distributed across the entire retina. 4.The density of cones is 200-fold higher in the fovea than in the most eccentric retinal regions. 5.The density of rods is highest in the far periphery of the retina.

The density of cones is 200-fold higher in the fovea than in the most eccentric retinal regions.

Stanley has a car accident and is discharged from the hospital with orders to notify his doctor of any changes in health or unusual behaviors. A few days later he notices that his cat was moving in a very strange way, appearing to jump from place to place, as if in an old-time cinema reel. Stanley then discovers his brother is moving in the same way. What part of Stanley's brain is dysfunctional? Select one: 1.The primary visual cortex 2.The dorsal visual pathway to the parietal lobe 3.The ventral visual pathway to the temporal lobe 4.The lateral geniculate nucleus 5.The retina

The dorsal visual pathway to the parietal lobe

Which statement about stabilized retinal images is false? Select one: 1.The fading of retinal images serves mainly to protect neurons in LGN and area 17 from photodamage. 2.More than 150 years ago, Purkinje showed that shadows of retinal blood vessels can be visualized with a light pressed against a closed eyelid. 3.Images of retinal blood vessels (or their shadows) disappear in a fraction of second when a light source is stabilized. 4.Retinal adaptation is thought to contribute to the stabilized image phenomenon. 5.Interocular transfer of the stabilized image effect indicates at least some role for central processing.

The fading of retinal images serves mainly to protect neurons in LGN and area 17 from photodamage.

Which statement about the organization of muscles and motor neurons is false? Select one: 1.Red muscle fibers contract slowly and produce the smallest amount of force. 2.Large motor neurons are recruited only at higher levels of stimulus intensity. 3.The fastest, strongest muscle fibers can produce the most sustained force output. 4.As stimulation of a motor unit increases, the amount of force produced by the muscle increases. 5.Individual muscles can be used in a variety of different locomotor patterns or gaits.

The fastest, strongest muscle fibers can produce the most sustained force output.

Which statement about primary motor cortex neurons is false? Select one: 1.The firing of primary motor cortical neurons occurs precisely at the onset of a muscle contraction. 2.Primary motor cortical neurons can be directionally selective. 3.The firing rate of a primary motor cortical neuron codes for or contributes to the force of a movement. 4.The directional control of a movement is coded by the activity of a population of primary motor cortical neurons. 5.The directional responses of primary motor cortical pyramidal cells tend to be broadly tuned in that they respond over a somewhat broad range of movement directions.

The firing of primary motor cortical neurons occurs precisely at the onset of a muscle contraction.

A dull probe stimulates a Pacinian corpuscle. An electrode is placed midway down the axon, and action potentials are recorded. After one second, the probe is pushed with greater force. What change will occur in the recording? Select one: 1.The height of action potentials will increase. 2.The frequency of action potentials will increase. 3.The frequency of action potentials will decrease. 4.The resting membrane potential will increase. 5.The threshold potential level will increase.

The frequency of action potentials will increase.

Which phenomenon explains the unidirectional propagation of action potentials? Select one: 1.The voltage dependence of the sodium channels 2.The voltage dependence of the potassium channels 3.The presence of a refractory period at a location where an action potential has just passed 4.Sufficient "leakiness" of the axons, such that backward propagation of action potentials is prevented 5.The polarized orientation of microtubules within the axon

The presence of a refractory period at a location where an action potential has just passed

Which statement about lateralization of brain functions is true? Select one: 1.Right-handers always show left-brain language dominance. 2.Left-handers always show right-brain language dominance. 3.There are no correlations between language and hand dominance. 4.There is evidence that language and hand dominance originated from a single genetic mutation in our early hominid ancestors. 5.The prevalence of dominance suggests that lateralization of function maximizes use of the available neural circuitry.

The prevalence of dominance suggests that lateralization of function maximizes use of the available neural circuitry.

Which statement regarding refractory periods is true? Select one: 1.They allow neurons to fire an unlimited number of action potentials per unit of time. 2.During the refractory period the cell requires a less intense stimulus to reach threshold. 3.The refractory period arises in part due to the increase in sodium conductance across the membrane. 4.The refractory period arises in part due to the decrease in potassium conductance across the membrane. 5.The refractory period ends when the sodium channels are no longer inactivated.

The refractory period ends when the sodium channels are no longer inactivated.

How does the resting membrane potential of a typical neuron compare to the equilibrium potential (calculated by the Nernst equation) for potassium? Select one: 1.The resting membrane potential is not exactly equal to the equilibrium potential for potassium because of variation among neurons. 2.The resting membrane potential is not exactly equal to the equilibrium potential for potassium because rapid fluctuations in membrane potential prevent accurate measurements. 3.The resting membrane potential is not exactly equal to the equilibrium potential for potassium because the membrane has some resting permeability to species other than potassium. 4.The resting membrane potential is not exactly equal to the equilibrium potential for potassium because potassium does not contribute to the resting membrane potential. 5.The resting membrane potential is exactly equal to the equilibrium potential for potassium.

The resting membrane potential is not exactly equal to the equilibrium potential for potassium because the membrane has some resting permeability to species other than potassium.

A student new to neuroscience research is practicing recording resting membrane potentials from giant squid axons. During one of the trials, the resting membrane potential, which is normally around -60 mV, measured -15 mV. Which statement best describes what might have occurred during the experiment? Select one: 1.The student added too much potassium to the extracellular solution. correct! 2.The student added too much sodium to the extracellular solution. 3.The student did not add enough potassium to the extracellular solution. 4.The student did not add enough sodium to the extracellular solution. 5.The student added too little potassium and too much sodium to the extracellular solution.

The student added too much potassium to the extracellular solution.

Which statement about the motor functions of the superior colliculus (SC) is false? Select one: 1.In the SC, location in visual space is mapped in register with an auditory map. 2.The SC helps to coordinate eye and head movements. 3.Neurons in a particular part of the SC are activated by stimuli in a specific region of visual space. 4.The SC assists in the transformation of sensory signals into motor commands. 5.The uppermost layer of the SC is a somatotopic map that enables us to look at different locations on our body.

The uppermost layer of the SC is a somatotopic map that enables us to look at different locations on our body.

Which statement about directional tuning and population coding by primary motor cortical neurons is true? Select one: 1.The precision of directional motor movements equals the precision of directional tuning of individual primary motor cortical pyramidal cells. 2.Most primary motor cortical neurons have two or three distinct, preferred directions separated by intervening ranges of non-preferred directions. 3.The vector summation of population responses of primary motor cortical neurons is important for directional control of motor movements. 4.Every possible direction of motion is made possible by specific populations of primary motor cortical neurons that are tuned specifically to each of the possible directions. 5.Primary motor cortical neurons do not code direction.

The vector summation of population responses of primary motor cortical neurons is important for directional control of motor movements

Which statement about "mirror" motor neurons is false? Select one: 1.They are found in the ventrolateral portion of premotor cortex. 2.They fire in response to a specific motor act, irrespective of there being a behavioral goal associated with the act. 3.They fire in response to observation of a particular motor act being performed by others. 4.They fire most strongly in response to an observed motor act that corresponds to the act that would activate the neuron during self-initiated movements. 5.They encode the intention to make a particular motor act.

They fire in response to a specific motor act, irrespective of there being a behavioral goal associated with the act.

Which is not a function of the reticular formation? Select one: 1.Modulation of cortical functions via serotonergic, noradrenergic, and cholinergic transmitter systems 2.Modulation of cortico-striatal interactions 3.Descending modulation of spinal reflexes 4.Coordination of gaze centers and branchiomotor functions 5.Transmission of spinal nociceptive and tactile sensory signals to the cerebellum

Transmission of spinal nociceptive and tactile sensory signals to the cerebellum

Which nucleus innervates the superior oblique muscle? Select one: 1.Trochlear nucleus 2.Abducens nucleus 3.Oculomotor nucleus 4.Lateral vestibular nucleus 5.Medial vestibular nucleus

Trochlear nucleus

Which statement regarding photoreceptor cells is true? Select one: 1.Like typical sensory neurons, they fire action potentials when the cell depolarizes to threshold in response to stimuli. 2.Unlike typical neurons, their resting membrane potential is more negative, usually around -100mV. 3.Unlike typical neurons, cation channels are open at rest, allowing the influx of sodium and calcium. 4.Unlike typical neurons, neurotransmitter release is dependent on an influx of potassium ions. 5.Unlike typical neurons, they hyperpolarize in response to a stimulus due to opening of chloride channels.

Unlike typical neurons, cation channels are open at rest, allowing the influx of sodium and calcium.

Visual area _______ is most specialized for processing color information. Select one: 1.V1 2.V2 3.V3 4.V4 5.V5

V4

For which reason was the development of the voltage clamp critical to investigations of the ionic basis of the action potential? Select one: 1.Voltage changes in the cell cannot be seen without voltage clamp. 2.Ionic conductances can be activated only in cells that have been voltage clamped. 3.Voltage clamping allows simultaneous control of membrane potential and measurement of permeability changes. 4.Sodium and potassium currents are activated in non-overlapping voltage regimes. 5.Voltage clamping does not require specialized equipment.

Voltage clamping allows simultaneous control of membrane potential and measurement of permeability changes.

A patient presents with migraines that usually last about 48 hours and are accompanied by vomiting. Two of his immediate relatives show similar symptoms. Which ion channel would you expect to be dysfunctional in this patient? Select one: 1.Voltage-gated calcium channel 2.Voltage-gated sodium channel 3.Ligand-gated chloride channel 4.Voltage-gated potassium channel 5.Ligand-gated sodium channel

Voltage-gated calcium channel

Which observation is not evidence that helped to identify sodium as the early current of the action potential? Select one: 1.The current declined when there was decreased driving force on sodium fluxes. 2.The current disappeared near the Nernst potential for sodium. 3.The early current was blocked by tetrodotoxin. 4.The early current was unaffected by tetraethylammonium. 5.When the late current was blocked, the reversal potential of the inward current shifted to a negative membrane potential.

When the late current was blocked, the reversal potential of the inward current shifted to a negative membrane potential.

Which statement regarding the diversity of ion channels is false? Select one: 1.With only six different types, potassium channels are the least diverse channel type. 2.There are at least 10 different sodium channels in humans. 3.Sodium channels that do not inactivate have been found. 4.There are least 10 different types of calcium channels. 5.Calcium channels serve diverse functions such as influencing action potential shape and mediating the release of neurotransmitters.

With only six different types, potassium channels are the least diverse channel type.

The technique that provides the most direct information about the physical, three-dimensional structure of ion channels is Select one: 1.the sequencing of the channel's amino acids. 2.physiological measurement of ion selectivity. 3.X-ray crystallography. 4.fluorescence imaging of channel subunit dynamics. 5.high-performance liquid chromatography.

X-ray crystallography.

For an OFF-center ganglion cell, which stimulus on the cell's receptive field would cause the highest rate of action potential firing? (In the figure, black fill indicates darkness, and white fill indicates light in the receptive field.) Select one: 1. a 2. b 3. c 4. d 5. Both a and d would cause the same level of activation

a

The patellar tendon (knee-jerk) reflex is Select one: 1.mediated by Golgi tendon organs. 2.a monosynaptic reflex arc mediated by Ia afferents. 3.a polysynaptic reflex arc that integrates the input from groups Ia, Ib, and II afferents. 4.mediated by collaterals of somatosensory afferents. 5.a volitional response to the impending impact of an object (i.e., the physician's rubber hammer) directed toward the knee.

a monosynaptic reflex arc mediated by Ia afferents.

The mechanism that accounts for light-induced hyperpolarization of photoreceptors is Select one: 1.the gating of ion channels by released retinal monomers. 2.a sudden increase in the concentration of cAMP, leading to activation of potassium channels. 3.a rapid fall in the concentration of cGMP, leading to closure of Na+ / Ca2+ channels. 4.a rapid rise in the concentration of cGMP, leading to closure of Na+ / Ca2+ channels. 5.light-induced photoisomerization of membrane-bound calcium channels.

a rapid fall in the concentration of cGMP, leading to closure of Na+ / Ca2+ channels.

In the upper layers (2 and 3) of primary visual cortex, a lateral sampling of pyramidal cell responses would reveal Select one: 1.alternating bands of monocular columns (left eye only/right eye only). 2.a population of binocular cells that respond equally well to both eyes. 3.a roughly sinusoidal pattern of ocular dominance moving from left dominance, through equal responsiveness, to right dominance, and then back. 4.only color-sensitive cells. 5.only orientation-selective cells.

a roughly sinusoidal pattern of ocular dominance moving from left dominance, through equal responsiveness, to right dominance, and then back.

The condition called "fused tetanus" refers to Select one: 1.lockjaw symptoms resulting from exposure to the tetanus toxin. 2.a muscle firing pattern resulting from one's willing a muscle to contract at maximum velocity. 3.the response of single muscle fibers to a single action potential input. 4.a sustained maximal contraction due to intense motor unit firing. 5.an excessive contraction that results in the fusing together of muscle fibers.

a sustained maximal contraction due to intense motor unit firing

The proteins that establish ionic gradients are called Select one: 1.passive transporters. 2.active transporters. 3.voltage-gated ion channels. 4.ligand-gated ion channels. 5.permeability transition pores.

active transporters.

A motor pool (as opposed to a motor unit) consists of Select one: 1.all of the motor neurons that project to a given muscle. 2.all of the motor neurons within a single segment of spinal cord. 3.all of the motor neurons that project to a given limb. 4.a single motor neuron and all of the muscles it innervates. 5.a single motor neuron and all of its afferent interneurons.

all of the motor neurons that project to a given muscle.

Neuropsychological testing Select one: 1.has been used only in animal studies. 2.allows for the systematic study of frontal lobe functions in humans. 3.is no longer used as a method for examining brain functions. 4.predominantly involves tests of personality. 5.can readily identify individuals with criminal intent.

allows for the systematic study of frontal lobe functions in humans.

The death of retinal cells in retinitis pigmentosa is most likely caused by Select one: 1.infection. 2.apoptosis. 3.excessive light exposure. 4.environmental toxins. 5.injury to the eye.

apoptosis

Wilder Penfield, in the course of epilepsy surgery, performed electrical stimulation of cortex for the main purpose of Select one: 1.avoiding damage to critical language brain structures during the surgery. 2.eliciting patient verbalizations to ensure that they were not feeling pain. 3.mapping language functions in areas that had not previously been studied. 4.mapping language functions with greater precision than previously accomplished. 5.testing success of the surgery.

avoiding damage to critical language brain structures during the surgery.

Damage to the left optic nerve would result in which type of visual field deficit? Select one: 1. a 2. b 3. c 4. d 5. e

b

The paddle-like, charged transmembrane domains of potassium channels may Select one: 1.serve as a plug or inactivation gate. 2.be the primary voltage sensors. 3.confer ion selectivity to the channel. 4.enable the aggregation of channel subunits into functional channels. 5.dehydrate the ions as they cross the membrane.

be the primary voltage sensors

Near and far cells are distinct from other pyramidal cells in terms of their sensitivity to Select one: 1.motion. 2.edges. 3.monocularity. 4.binocular disparity. 5.oscillating luminance.

binocular disparity.

As evidenced by the studies of Carl Wernicke, patients with damage to the left temporal lobe Select one: 1.show diverse motor deficits along with speech generation deficits. 2.show diverse sensory deficits along with receptive language deficits. 3.can produce words but have difficulty understanding language. 4.can understand language but cannot produce organized speech. 5.lose the capacity to produce and understand specific categories of words (e.g., verbs).

can produce words but have difficulty understanding language

As evidenced by the studies of Paul Broca, patients with damage to the ventroposterior region of the left frontal cortex Select one: 1.show diverse motor deficits along with speech generation deficits. 2.show diverse sensory deficits along with receptive language deficits. 3.are able to produce words but have difficulty understanding language. 4.can understand language but cannot produce organized speech. 5.lose the capacity to produce and understand specific categories of words (e.g., verbs).

can understand language but cannot produce organized speech.

Cortical areas that plan and initiate motor sequences Select one: 1.all fall within the primary motor cortex. 2.comprise five functionally distinct and anatomically isolated regions. 3.comprise several functionally distinct but highly interconnected regions. 4.all receive direct inputs from the basal ganglia. 5.all show a high threshold for the elicitation of motor behaviors.

comprise several functionally distinct but highly interconnected regions.

Studies of the ionic basis of the action potential in squid giant axon found that Select one: 1.decreasing sodium outside the cell decreases the size of the action potential. correct! 2.decreasing sodium outside the cell increases the size of the action potential. 3.decreasing potassium outside the cell decreases the size of the action potential. 4.decreasing potassium outside the cell increases the size of the action potential. 5.manipulating sodium has large effects on both the size of the action potential and the resting membrane potential.

decreasing sodium outside the cell decreases the size of the action potential.

Voltage clamp data, in which investigators analyzed membrane conductances during action potentials, showed all of the following except: Select one: 1.the sodium current was rapidly activated by depolarization. 2.the potassium current activates on a comparatively slow time scale of a few ms. 3.at certain potentials, there can be zero current even with a large conductance. 4.depolarization leads to a time-dependent inactivation of the sodium current. 5.depolarization leads to a time-dependent inactivation of the potassium current.

depolarization leads to a time-dependent inactivation of the potassium current.

Spinal interneurons that project ipsilaterally between the lumbar and cervical enlargements are most likely involved with Select one: 1.ensuring left-right alternation during rhythmic behaviors. 2.ensuring coordination of the forelimbs and hindlimbs. 3.ensuring the proper speed of locomotion. 4.coordinating activity of limb joints and extremities. 5.producing alternating flexion and extension patterns in an individual limb.

ensuring coordination of the forelimbs and hindlimbs.

Electrophysiological studies in non-human primates allow scientists to Select one: 1.examine the responses of single cortical neurons in awake, behaving subjects. 2.knockout genes important to cognitive tasks in specific regions of interest. 3.understand how the CNS processes information in the parietal lobe by testing identification capabilities. 4.understand how the CNS processes information in the temporal lobe by testing planning capabilities.

examine the responses of single cortical neurons in awake, behaving subjects.

A specialized motor unit, with an average size of three muscle fibers, controls Select one: 1.finger movements. 2.postural muscle. 3.the large, fast contracting muscles used in sprinting. 4.eye muscles. 5.muscles of high-endurance athletes.

eye muscles.

In an anticipatory postural response of a standing person about to tug on a handle, the early response of leg muscles (such as the gastrocnemius) that precedes the actual tug is an example of Select one: 1.feedforward motor control. 2.feedback motor control. 3.equilibrium-point motor control. 4.a "winner take all" motor coding strategy. 5.sparse population coding.

feedforward motor control.

In relation to other retinal ganglion cells, a P ganglion cell has Select one: 1.a larger receptive field and sustained responses. 2.a larger receptive field, a faster-conducting axon, and transient responses. 3.a faster-conducting axon, finer spatial resolution, and better color sensitivity. 4.finer spatial resolution and better color sensitivity. 5.transient responses and better color sensitivity.

finer spatial resolution and better color sensitivity.

In terms of brain anatomy, the largest lobes in humans are the _______ lobes. Select one: 1.frontal 2.occipital 3.temporal 4.parietal 5.All lobes are roughly equivalent in size.

frontal

The part of cerebral cortex that is especially important for selecting and planning appropriate behavioral responses is the _______ lobe. Select one: 1.occipital 2.parietal 3.temporal 4.frontal 5.cognitive

frontal

The lamprey central pattern generator (CPG) Select one: 1.produces dorsal-ventral flexion waves that run the length of the body. 2.requires sensory feedback in order for the spinal CPG to oscillate. 3.is controlled by a series of segmental ganglia. 4.generates an alternating left-right bending pattern by means of crossed inhibitory fibers. 5.is easy to study because there are only four cells in each hemi-segment of the spinal cord.

generates an alternating left-right bending pattern by means of crossed inhibitory fibers.

Korbinian Brodmann was known for his Select one: 1.neurophysiological studies of neocortical pyramidal cells. 2.generation of cytoarchitectonic maps of the brain. 3.pioneering work in visual-spatial neglect syndrome. 4.surgical technique for leukotomies. 5.behavioral studies on the functions of the frontal lobes in monkeys.

generation of cytoarchitectonic maps of the brain.

The TRP ion channel family includes channels responsive to Select one: 1.complex sequences of voltage commands. 2.heat and cold. 3.intracellular cyclic nucleotides. 4.hyperpolarization. 5.ultraviolet light.

heat and cold.

In the phase labeled D, the voltage-gated sodium channels are ________ and the voltage-gated potassium channels are ________. Select one: 1. open; closed 2. closed; open 3. open; open 4. inactivated; open 5. closed; inactivated

inactivated; open

Although the phenomenon is not well understood, the increased muscle tone and spasticity that develop after an upper motor neuron injury appears to be due, at least in part, to Select one: 1.increased responsiveness of motor neurons to Ia afferent inputs. 2.decreased responsiveness of motor neurons to Ia afferent inputs. 3.pooling of GABA in the spinal gray matter. 4.pooling of glutamate in the spinal gray matter. 5.increased activity of undamaged descending upper motor neurons.

increased responsiveness of motor neurons to Ia afferent inputs.

"Spike-triggered averaging" Select one: 1.refers to the generation of "average" motor behaviors by individual spikes. 2.can be done only on awake, behaving monkeys. 3.requires use of the patch-clamp technique to resolve spikes associated with single ion channels. 4.is a means of correlating upper motor neuron activity with muscle activation. 5.is used to determine the exact number of motor neurons contributing to each electromyogram (EMG) signal.

is a means of correlating upper motor neuron activity with muscle activation.

The retinal information that axons carry through the left internal capsule to visual cortex Select one: 1.comes from the left eye only. 2.comes from the right eye only. 3.is 90% from the left eye. 4.is 90% from the right eye. 5.is a roughly 60/40 split of information from the two eyes.

is a roughly 60/40 split of information from the two eyes.

Macular sparing Select one: 1.is associated exclusively with cortical damage. 2.results only from bilateral damage to the optic tracts. 3.results only from bilateral damage to the optic nerves. 4.is a transient phenomenon that precedes total blindness. 5.is a selective preservation of vision, the basis of which is unknown.

is a selective preservation of vision, the basis of which is unknown.

A patient holding a ball in his right hand identifies it as "a ball," but when holding it in his left hand he calls it "a round thing." This patient most likely Select one: 1.is a split-brain patient. 2.is undergoing the Wada procedure. 3.has Wernicke's aphasia. 4.has Broca's aphasia. 5.has dysarthria.

is a split-brain patient.

The anatomical asymmetry of the planum temporale Select one: 1.explains the known correlations between language and handedness. 2.is diminished in right-handers. 3.is diminished in left-handers. 4.shows a perfect correlation with language dominance. 5.is detectable in about two-thirds of humans.

is detectable in about two-thirds of humans.

A "muscle field" Select one: 1.includes all of the muscles that are co-activated during any given behavior. 2.includes all of the upper motor neurons that innervate a particular lower motor neuron. 3.is the group of muscles whose activity is directly facilitated by a given upper motor neuron. 4.is the force vector produced by stimulating an individual upper motor neuron. 5.is the force vector produced by stimulating a small field of cortical premotor neurons.

is the group of muscles whose activity is directly facilitated by a given upper motor neuron.

The structure that is important to the production of virtually all vocalizations is the Select one: 1.pharynx. 2.larynx. 3.tongue. 4.nasal cavity. 5.epiglottis.

larynx

The fovea Select one: 1.covers approximately 40 percent of the retina. 2.lies at the center of the optic disk. 3.lies at the center of the macula lutea. 4.is synonymous with "fundus." 5.is the only part of the retina that contains xanthophyll.

lies at the center of the macula lutea.

In the pupillary light reflex of a healthy individual, Select one: 1.the reflex is elicited only by simultaneous photic stimulation of both eyes. 2.light falling on the left eye will cause only left pupil constriction. 3.light falling on the right eye will cause only left pupil constriction. 4.light falling on one eye will cause both pupils to constrict equally. 5.light falling on the left eye will cause both pupils to constrict, but the left will constrict about twice as much as the right.

light falling on one eye will cause both pupils to constrict equally.

When visually examining an object such as a painting of a face, a person will usually Select one: 1.focus on just one point on the painting to obtain a sense of the gestalt. 2.raster scan their eyes across the painting, much like a television camera. 3.make many rapid eye movements in different directions, acquiring the most information during the times when the eye is moving across the object. 4.make many rapid eye movements, in different directions, acquiring information primarily during brief pauses at different locations on the object. 5.make eye movements that trace along different contours of the object, until the entire object is perceived.

make many rapid eye movements, in different directions, acquiring information primarily during brief pauses at different locations on the object.

The synaptic potential: Select one: 1.makes communication between nerve cells possible. 2.occurs only in response to external stimuli. 3.propagates along axons. 4.determines the cell's resting potential. 5.results in a long-term change in a cell's membrane potential.

makes communication between nerve cells possible.

The rubrospinal pathway Select one: 1.receives direct visual inputs. 2.projects from the superior colliculus (or optic tectum) to the spinal cord. 3.is the main pathway by which vestibular information is conveyed to the spinal cord. 4.controls all head and eye movements. 5.might not exist in humans.

might not exist in humans.

Golgi tendon organs are most sensitive to Select one: 1.muscle tension. 2.muscle stretch. 3.absolute joint position. 4.muscle contraction frequency. 5.muscle fatigue.

muscle tension.

Studies of neuronal responses in the temporal cortex of the rhesus monkey have revealed Select one: 1.individual cells that are tuned to a specific object only. 2.individual cells that fire in response to one specific familiar face. 3.norm-based tuning and population coding of objects. 4.tonic firing for a variety of related objects of various sizes, colors, and orientations. 5.activation of cells based on subjective preference for an object.

norm-based tuning and population coding of objects.

A contralateral visual field deficit is Select one: 1.found only in association with scotomas. 2.often due to optic tract or cortical damage. 3.found only with damage to the LGN. 4.indicative of a pituitary tumor. 5.caused by damage to just one optic nerve.

often due to optic tract or cortical damage.

In the phase labeled B, the voltage-gated sodium channels are ________ and the voltage-gated potassium channels are ________. Select one: 1. open; closed 2. closed; open 3. open; open 4. inactivated; open 5. closed; inactivated

open; closed

The delayed response task has been used to examine Select one: 1.neuronal activity near the central sulcus during a response delay period. 2.long-term memory ability. 3.performance impairments in monkeys with bilateral prefrontal lesions. 4.impulse control in humans. 5.reward preference in monkeys.

performance impairments in monkeys with bilateral prefrontal lesions.

The two main functions of the retinal pigment epithelium are _______ and _______. Select one: 1.structural support to maintain curvature of the retina; phagocytosis of shed outer segments 2.structural support to maintain curvature of the retina; synthesis of rhodopsin 3.phagocytosis of shed outer segments; synthesis of rhodopsin 4.phagocytosis of shed outer segments; regeneration of the photoreceptor photopigments 5.synthesis of rhodopsin; regeneration of the photoreceptor photopigments

phagocytosis of shed outer segments; regeneration of the photoreceptor photopigments

The "indirect pathway" from cortex to spinal cord does not play a role in Select one: 1.feed-forward postural adjustments. 2.weight shifts, as when a cat lifts one paw. 3.certain motor functions that are spared after damage to the direct corticospinal pathway. 4.post-injury recovery of fine motor functions such as using two fingers to pick up food. 5.relaying information from cortex to spinal cord via the reticulospinal neurons.

post-injury recovery of fine motor functions such as using two fingers to pick up food.

In the phase labeled D, _______ ions are moving _______ the cell. Select one: 1. potassium; into 2. sodium; into 3. potassium; out of 4. sodium; out of 5. both sodium and potassium; out of

potassium; out of

According to current consensus, the most likely role of the right hemisphere in language is in the Select one: 1.lower-level analysis of sensory signals from which the meaning of language is extracted. 2.programming of word sequences based on their semantic content. 3.processing the emotional and tonal (prosodic) components of language. 4.reading and writing of languages with spatially complex characters, such as Mandarin Chinese. 5.communication of sign language

processing the emotional and tonal (prosodic) components of language.

The _______ most directly affects the rate of information processing within the central nervous system. Select one: 1.number of sodium channels along an axon 2.number of potassium channels along an axon 3.propagation speed of action potentials 4.threshold voltage of neurons 5.ratio of sodium to potassium channels

propagation speed of action potentials

Asynchronous firing of motor neurons Select one: 1.provides a means by which a population of motor neurons can maintain constant force over a finite time interval. 2.refers to the pattern by which more lateral motor neurons are fired first and more medial ones later. 3.refers to alternating firing of fast-twitch and slow-twitch muscle fibers. 4.does not occur under normal physiological conditions. 5.is observed only in the Îł motor neurons.

provides a means by which a population of motor neurons can maintain constant force over a finite time interval.

Thalamic nuclei that are not involved in relaying primary motor or sensory input, but do have inputs to association cortices, are the _______ and _______ nuclei. Select one: 1.pulvinar; medial geniculate 2.medial geniculate; lateral dorsal 3.ventral posterior; lateral dorsal 4.reticular; lateral geniculate 5.pulvinar; medial dorsal

pulvinar; medial dorsal

The calcium ATPase Select one: 1.is much simpler than the sodium-potassium pump because it has only three transmembrane regions. 2.pumps 15 calcium ions for each molecule of ATP consumed. 3.uses the same intracellular domain for both nucleotide binding and ion translocation. 4.pumps calcium in a cyclical process that utilizes energy from ATP. 5.is unique among transporters in that its pumping action involves no conformational changes.

pumps calcium in a cyclical process that utilizes energy from ATP.

When Graziano and colleagues extended cortical microstimulation in monkeys to time epochs approximating those of natural movements, they observed Select one: 1.seizure-like contractions of a small group of muscles. 2.repetitive movements of a limb or trunk muscle. 3.sequential movements that were disrupted by "interfering" movements. 4.purposeful movements distributed sequentially across multiple joints. 5.increasingly strong movements eventually leading to spasticity.

purposeful movements distributed sequentially across multiple joints.

The current flowing through individual ion channels Select one: 1.was visualized with the advent of the voltage clamp in 1956. 2.exhibits the same time course across all individual sodium channels. 3.reflects the passage of thousands of ions per millisecond. 4.has a different voltage dependence than the macroscopic ionic current has. 5.has a different reversal potential than the macroscopic ionic current has.

reflects the passage of thousands of ions per millisecond.

The iris Select one: 1.is responsible for the refraction of light onto the retina. 2.regulates the amount of light entering the eye. 3.applies tension to the lens. 4.contains the pigment epithelial cells that nourish photoreceptors. 5.covers the cornea, shielding it from harmful UV rays.

regulates the amount of light entering the eye.

Information on the role of the parietal lobe in selective attention was obtained by Select one: 1.punishing monkeys for making mistakes. 2.rewarding monkeys for making correct choices. 3.training genetically-modified mice to recognize objects. 4.training monkeys to associate arbitrary symbols with assorted objects. 5.recording from neurons in unconscious monkeys.

rewarding monkeys for making correct choices.

A surprising result that emerged from the molecular and genetic analysis of ion channels was the Select one: 1.size of the individual ion channels. 2.voltage-dependence of the ion channels. 3.time-dependence of the ion channels. 4.discovery of differences in ionic selectivity. 5.sheer number of different ion channels.

sheer number of different ion channels.

During the 1950s and 1960s Norman Geschwind Select one: 1.confirmed the functions of Broca's and Wernicke's areas by lesioning analogous areas in chimps. 2.confirmed the functions of Broca's and Wernicke's areas by making experimental lesions in humans in the context of neurosurgery to treat epilepsy. 3.conducted X-ray-based studies on localization of language areas. 4.showed that Broca's and Wernicke's areas have many functions other than language. 5.showed that a number of cortical areas (other than Broca's and Wernicke's areas) have specialized language functions.

showed that a number of cortical areas (other than Broca's and Wernicke's areas) have specialized language functions

In the phase labeled B, _______ ions are moving _______ the cell. Select one: 1. potassium; into 2. sodium; into 3. potassium; out of 4. sodium; out of 5. both sodium and potassium; into

sodium; into

The motor neurons innervating the medial gastrocnemius muscle of the cat are found Select one: 1.concentrated within a single segment of cervical spinal cord. 2.concentrated within a single segment of lumbar spinal cord. 3.spanning several segments of medial lumbar and sacral spinal cord. 4.spanning several segments of lateral lumbar and sacral spinal cord. 5.distributed diffusely throughout the dorsal and ventral horns of lumbar and sacral spinal cord.

spanning several segments of lateral lumbar and sacral spinal cord.

The initial discovery that humans possess language-specific cortical areas was a result of Select one: 1.studies of patients with brain lesions. 2.electrophysiological recording experiments. 3.early X-ray brain imaging experiments. 4.genetic analysis of precursor "language" areas in non-human primates. 5.neuroanatomical tracing experiments.

studies of patients with brain lesions.

The most essential function of the core cortical language areas is Select one: 1.early processing of speech sounds. 2.assembling sound sequences into word-length auditory percepts. 3.generation of speech motor patterns. 4.generation of gestures. 5.symbolic representation.

symbolic representation.

Upper motor neurons Select one: 1.control the upper half of the torso. 2.synapse on muscles in the eye, neck, and head. 3.synapse on local circuit neurons and/or lower motor neurons. 4.affect motor patterns only indirectly via their inputs to the basal ganglia. 5.have cell bodies that are located in the ventral horn of the spinal cord.

synapse on local circuit neurons and/or lower motor neurons.

Corticospinal axons mostly Select one: 1.send ipsilateral axons into the lateral corticospinal tract. 2.send contralateral axons into the ventral (anterior) corticospinal tract. 3.synapse onto spinal Îą motor neurons. 4.synapse onto spinal local circuit neurons. 5.synapse onto spinal Îł motor neurons.

synapse onto spinal local circuit neurons.

The _______ association cortex is involved in recognizing objects, while the _______ association cortex is involved in deciding what to do with the object. Select one: 1.temporal; frontal 2.frontal; parietal 3.parietal; temporal 4.temporal; parietal 5.frontal; temporal

temporal; frontal

The part of the motor system that acts as a servomechanism to minimize motor error is Select one: 1.Brodmann's area 4. 2.Brodmann's area 6. 3.the brainstem. 4.the cerebellum. 5.the basal ganglia.

the cerebellum.

When current is injected into an axon, Select one: 1.an action potential is evoked before the current has spread any distance from the point of injection. 2.the current will spread in only one direction. 3.the current will spread passively only if it is a depolarizing current. 4.the current will decay exponentially with increasing distance from the injection site (if no action potential is present). 5.the current will propagate as an oscillating wave independently of its polarity.

the current will decay exponentially with increasing distance from the injection site (if no action potential is present).

The squid giant axon is useful in neuronal studies because Select one: 1.its axon is easy to penetrate with recording electrodes because it is so long. 2.the cytoplasm in the axon can be extruded, thus allowing studies of its composition. 3.multiple synapses between the nerve cells make them easy to study. 4.its giant ion channels allow insertion of recording electrodes into the channels. 5.the axon has fewer ion channels, which simplifies the analysis of observations.

the cytoplasm in the axon can be extruded, thus allowing studies of its composition.

Hodgkin and Katz proposed that sodium was the predominant ion associated with the firing of an action potential because Select one: 1.the membrane potential approaches the Na+ Nernst potential during the rising phase. correct! 2.the membrane potential approaches the Na+ Nernst potential during the falling phase. 3.sodium ions can move more quickly than other ionic species. 4.sodium ions are the only ions that can flow into the nerve cell body. 5.the sodium gradient explains the rising phase, falling phase, and overshoot of the action potential.

the membrane potential approaches the Na+ Nernst potential during the rising phase.

The acute phase of upper motor neuron syndrome is characterized by Select one: 1.the passive dropping of an affected limb that has been elevated and then released. 2.the tendency of an affected limb to remain in any position in which it has been placed. 3.an infant-like Babinski response. 4.spasticity. 5.random waves of muscle contraction that propagate throughout the affected limb and body parts.

the passive dropping of an affected limb that has been elevated and then released.

Phonemes are Select one: 1.basic speech sounds, in general. 2.the vowel-like speech sounds. 3.the consonant-like speech sounds. 4.the percepts elicited by different speech sounds. 5.a new kind of auditory percept emerging from ubiquitous cell phone ring tones

the percepts elicited by different speech sounds.

The main reason that rods are more sensitive to light than cones is that Select one: 1.the photopigment of rods is much more sensitive to light than the photopigment used in cones. 2.the eye contains 1000 times as many rods as cones. 3.the rod transduction mechanism provides greater signal amplification. 4.rods are sensitive to a much broader range of wavelengths. 5.rods have many different types of opsin proteins.

the rod transduction mechanism provides greater signal amplification.

In familial hemiplegic migraine, the underlying mutation in a calcium channel causes Select one: 1.abnormally functioning pain receptors in the peripheral nervous system. 2.enhanced synaptic excitation of second-order pain sensitive neurons. 3.abnormal activation of thalamic pain centers. 4.abnormal activation of neocortical pain centers. 5.the syndrome by some unknown mechanism.

the syndrome by some unknown mechanism.

When shaking one's head back and forth while looking straight ahead at a stationary object, the mechanism that maintains the focal image at a roughly constant location on the retina is called Select one: 1.retinal stabilization. 2.the vestibulo-ocular reflex. 3.the oculomotor reflex. 4.smooth pursuit. 5.the optokinetic reflex.

the vestibulo-ocular reflex.

One candidate hypothesis for the selective degeneration of lower and upper motor neurons in ALS is that Select one: 1.these neurons share distinct sets of G-protein-coupled receptors. 2.these neurons exhibit high resting firing rates. 3.motor neurons are used far more intensively than other CNS cell types. 4.these cells are exposed to infectious agents via their peripheral projections. 5.their very long axons make them more vulnerable to defects in axonal transport.

their very long axons make them more vulnerable to defects in axonal transport.

Lesions of the left frontal eye field result in Select one: 1.persistent, debilitating eye movements to the left. 2.persistent, debilitating eye movements to the right. 3.transient deviation of the eye to the left, plus a transient contralateral saccade deficit. 4.transient deviation of the eye to the right, plus a transient contralateral saccade deficit. 5.virtually no detectable deficit in any eye movements.

transient deviation of the eye to the left, plus a transient contralateral saccade deficit.

The leukotomy was used in the 1930s and 1940s predominantly as a(n) Select one: 1.alternative treatment to the psychotropic medications available at the time. 2.experimental technique for studying brain function in rats. 3.treatment for schizophrenia and other mental illnesses. 4.procedure for enhancing the intelligence of developmentally handicapped individuals. 5.treatment for severe epilepsy.

treatment for schizophrenia and other mental illnesses

Our underwater vision is poor because Select one: 1.water disperses light, making it impossible to focus. 2.under water there is no longer a refractive index difference between the cornea and the surrounding media. 3.water seeps into the iris, causing temporary cloudiness. 4.the hydrostatic pressure of water changes the shape of the eyeball. 5.the ions in the water cause hyperpolarization in the photoreceptor cells.

under water there is no longer a refractive index difference between the cornea and the surrounding media.