NSCI 175 Exam 2

Which of the following mediates vital bodily functions?

A. Cerebrum

B. Brain stem

C. Cerebellum

D. Meninges

B. Brain stem

Axons of the nervous system are described as afferent and efferent according to the direction in which they carry information. Which of the following represents an efferent projection?

A. Interneurons in the spinal cord

B. Motor output of the spinal cord

C. Sensory input to the spinal cord, Motor output of the spinal cord, Interneurons in the spinal cord

D. Sensory input to the spinal cord

B. Motor output of the spinal cord

At what point do the somatic sensory axons enter the spinal cord?

A. Dorsal roots

B. Ventral roots

C. Dorsal root ganglia

D. Ventral root ganglia

A. Dorsal roots

Where is CSF produced?

A. Diencephalon

B. Choroid plexus in the cerebral ventricles

C. Subarachnoid space

D. Arachnoid villi

B. Choroid plexus in the cerebral ventricles

The left and right portions of the body are divided by the _______ plane.

A. horizontal

B. sagittal

C. coronal

D. frontal

B. sagittal

In which plane of section would it be easiest to see the corpus callosum?

A. Coronal cut at the level of the cerebellum

B. Sagittal cut directly down the midline

C. Sagittal cut at the level of the temporal lobe

D. Horizontal cut at the level of the brainstem

B. Sagittal cut directly down the midline

Which major white matter system bridges the cerebral hemispheres?

A. Dorsal columns

B. Corpus callosum

C. Internal capsule

D. Posterior capsule

B. Corpus callosum

The brain and spinal cord are wrapped in protective membranes known collectively as the

A. meninges.

B. myelin.

C. dura mater.

D. pia mater.

A. meninges.

What are the advantages of MRI over CT scan?

A. Yields a more detailed map of the brain

B. Does not use X-irradiation, Yields a more detailed map of the brain, Images of brain slices can be made in any plane desired

C. Does not use X-irradiation

D. Images of brain slices can be made in any plane desired

B. Does not use X-irradiation, Yields a more detailed map of the brain, Images of brain slices can be made in any plane desired

Which membrane lies closest to the brain?

A. Arachnoid

B. Pia mater

C. Dura mater

D. Meninges

B. Pia mater

The ridges of tissue on the convoluted surface of the cortex are called

A. sulci.

B. ganglia.

C. gyri.

D. nuclei.

C. gyri.

Which of the following is the most posterior cerebral lobe in the brain?

A. Temporal lobe

B. Frontal lobe

C. Parietal lobe

D. Occipital lobe

D. Occipital lobe

The brainstem contains which of the following structures?

A. Medulla

B. Cerebellum

C. Corpus callosum

D. Central sulcus

A. Medulla

Which region of the cortex is crucial for motor control?

A. Prefrontal cortex

B. Postcentral gyrus

C. Precentral gyrus

D. Parietal lobe

C. Precentral gyrus

How many distinct layers are observed in the human neocortex?

A. One

B. Three

C. About one million

D. Six

D. Six

In the cerebral cortex, layer 5 is especially noticeable because it

A. contains many fibers.

B. is a different color from the rest.

C. contains many large cell bodies.

D. is quite variable from region to region.

C. contains many large cell bodies.

Neurons in the __________ are often referred to as the gateway to the cerebral cortex.

A. Brain stem

B. Cerebellum

C. Olfactory bulb

D. Thalamus

D. Thalamus

Which region of the cortex is necessary for vision?

A. Postcentral gyrus

B. Frontal cortex

C. Occipital cortex

D. Temporal cortex

C. Occipital cortex

The following are major cell groups in the brain (select all that apply):

A. septal area

B. caudate nucleus

C. fornix

D. corpus collosum

E. putamen

A,B,E

What changes occur in taste receptors when the membrane is depolarized during receptor potential?

A. Voltage-gated Ca2+ channels open, triggering the release of neurotransmitter.

B. Voltage-gated K+ channels open, triggering the release of neurotransmitter.

C. Voltage-gated Ca2+ channels open, inhibiting the release of neurotransmitter.

D. Voltage-gated K+ channels open, inhibiting the release of neurotransmitter.

A. Voltage-gated Ca2+ channels open, triggering the release of neurotransmitter.

How does the brain distinguish between alternative tastes?

A. By roughly labeled lines and population coding

B. Only by precisely labeled lines

C. By frequency distribution

D. Only by population coding

A. By roughly labeled lines and population coding

Why do we not confuse the tastes of bitter chemicals with sweet ones?

A. The receptor proteins are expressed in different cells.

B. The tastes are differentiated by the olfactory cortex.

C. The chemicals activate different second messenger systems.

D. There are 30 types of bitter receptors.

A. The receptor proteins are expressed in different cells.

Which cranial nerve(s) carry taste information from the taste buds to the brain?

A. Facial nerve, glossopharyngeal nerve, and vagus nerve

B. Abducens nerve, glossopharyngeal nerve, and hypoglossal nerve

C. Trigeminal nerve, trochlear nerve, and facial nerve

D. Vagus nerve, olfactory nerve, and hypoglossal nerve

A. Facial nerve, glossopharyngeal nerve, and vagus nerve

Which is true of population coding?

A. A large number of neurons specify the properties of a stimulus.

B. Receptor cells are each responsive to only a single taste.

C. Temporal patterns of spiking codes determine the quality of an odor.

D. There is an orderly spatial arrangement of neurons.

A. A large number of neurons specify the properties of a stimulus.

Which of the following occurs during sour taste transduction?

A. H+ influx depolarizes the cell.

B. Na+ influx depolarizes the cell.

C. Ca2+ influx depolarizes the cell.

D. K+ influx depolarizes the cell.

A. H+ influx depolarizes the cell.

Salty taste is mediated by

A. None of the above

B. sodium ions.

C. hydrogen ions.

D. slow, metabotropic receptors.

B. sodium ions.

People perceive sweet

A. only on the left side of the tongue.

B. only at the tip of the tongue.

C. anywhere on the tongue where there are taste receptors.

D. only on the right side of the tongue.

C. anywhere on the tongue where there are taste receptors.

What of the following is not typically considered one of the basic tastes?

A. Salty

B. Umami

C. Sour

D. Spicy

D. Spicy

What are chemoreceptors?

A. Chemically sensitive cells that mediate synapses at the neuromuscular junction

B. Special types of muscle cells sensitive to chemical changes in the extracellular milieu

C. Cells releasing hormones into the extracellular environment

D. Chemically sensitive cells that serve as sensory receptors

D. Chemically sensitive cells that serve as sensory receptors

What is the function of odorant-binding proteins in the mucus?

A. Produce the mucus

B. May concentrate odorants

C. May bind to viruses and bacteria

D. Generate new receptor cells

B. May concentrate odorants

What is the consequence of knocking out critical proteins of the olfactory cAMP pathway in mice?

A. Anosmia occurs.

B. Receptor cells degenerate.

C. Channels in cilia are sensitized.

D. Odorants diffuse away.

A. Anosmia occurs.

What mechanism(s) does the brain use to distinguish between smells?

A. Only olfactory maps

B. Only temporal code

C. Only population code

D. Olfactory map, temporal code, and population code

D. Olfactory map, temporal code, and population code

The olfactory epithelium contains all of the following types of cells except _______ cells.

A. glomerular

B. supporting

C. basal

D. receptor

A. glomerular

Outputs from the olfactory bulb make synaptic connections to all of the following except the

A. olfactory cortex.

B. temporal lobe structures.

C. thalamus.

D. olfactory tubercle.

C. thalamus.

We smell with our nose.

A. True

B. False

B. False

The vomeronasal system appears to specialize in detecting

A. pheromones.

B. pungent smells.

C. phonemes.

D. odors.

A. pheromones.

Transduction is

A. a process that converts stimuli in the environment into electrical responses in sensory receptor cells.

B. how odorants in the environment are detected by our sensory receptors.

C. a method for measuring pheromones.

D. both A and B.

A. a process that converts stimuli in the environment into electrical responses in sensory receptor cells.

Which of the following are true? Select all that apply.

A. Transduction molecules are found in cilia.

B. Olfactory receptors only use one type of molecular signaling system.

C. Binding of odorants to receptor proteins generates an action potential.

D. Most odorants bind to ion channel receptors.

A,B

Why there is no sensation of light at the optic disk?

A. Because there are no photoreceptors in the optic disk

B. Because light doesn't reach the optic disc

C. Because of the presence of the vitreous humor

D. Because the optic disk is a theoretical construct

A. Because there are no photoreceptors in the optic disk

Which cells in the retina have axons that leave the retina?

A. Photoreceptors

B. Ganglion cells

C. Bipolar cells

D. Photoreceptors, bipolar cells, and ganglion cells

B. Ganglion cells

Why does the fovea appear like a pit in a cross-sectional view of the retinal?

A. Because of the presence of other cells in the fovea that might scatter light

B. Because photoreceptors are smaller in the fovea

C. Because of a low ratio of photoreceptors to ganglion cells in the fovea

D. Because of the lateral displacement of cells above the photoreceptors in the fovea

D. Because of the lateral displacement of cells above the photoreceptors in the fovea

What is a difference between ON-center ganglion cells and OFF-center ganglion cells?

A. ON-center ganglion cells receive input from ON bipolar cells, whereas OFF-center ganglion cells receive input from OFF bipolar cells.

B. ON-center ganglion cells respond to stimulation of their receptive field centers with a transient burst of action potentials, whereas OFF-center ganglion cells respond with a sustained discharge.

C. ON-center ganglion cells constitute about 90% of the ganglion cell population, whereas OFF-center ganglion cells constitute about 5% of the ganglion population.

D. In an ON-center ganglion cell, the response to stimulation of the center is canceled by the response to stimulation of the surround, but this response cancellation does occur in an OFF-center ganglion cells.

A. ON-center ganglion cells receive input from ON bipolar cells, whereas OFF-center ganglion cells receive input from OFF bipolar cells.

Which layer contains the light-sensitive elements of the retina?

A. Outer plexiform layer

B. Photoreceptor layer

C. Ganglion cell layer

D. Inner nuclear layer

B. Photoreceptor layer

The optic tract makes synaptic connections at (select all that apply):

A. LGN

B. primary visual cortex

C. midbrain

D. hypothalamus

A,C,D

Ganglion cell axons carrying light information can influence (select all that apply)

A. saccadic eye movement

B. pupil size

C. head movement

D. sleep and wakefulness

A,B,C,D

Three important points to remember about retinotopy (select all that apply):

A. there are pictures in the primary visual cortex

B. perception is based on the brain's interpretation of distributed activity patterns

C. there is overlap of receptive fields in the primary visual cortex

D. there is some distortion of the map

B,C,D

James, age 22 years, was riding a motorbike when he had an accident. A neuropsychological test revealed that James suffered extensive damage to area V4 in the ventral stream. What is the most likely deficit resulting from a V4 lesion?

A. Peripheral vision deficit

B. Motion perception deficit

C. Total vision deficit

D. Color perception deficit

D. Color perception deficit

Which of the following is the most likely basis of visual perception?

A. Concerted activity of many neurons throughout the visual pathways

B. Binocular neurons in striate cortex

C. Hierarchical organization of visual receptive fields culminating in highly specialized cells such as grandmother cells

D. Decussation at the optic chiasm, projecting the left visual field to the right brain and the right field to the left brain

A. Concerted activity of many neurons throughout the visual pathways

The dorsal stream processes information related to (select all that apply):

A. visual control of action

B. faces

C. object recognition

D. visual motion

A,D

This type of cell has elongated orientation selective receptive fields with ON and OFF subregions:

A. simple cell

B. fusiform cell

C. complex cell

D. ON-center ganglion cells

A. simple cell

Which of the following has large receptive fields that may cover an entire finger or half of the palm?

A. Meissner's corpuscles

B. Krause end bulbs

C. Pacinian corpuscles

D. Merkel's disks

C. Pacinian corpuscles

What are mechanoreceptors?

A. Sensitive to high-frequency vibrations

B. Sensitive to temperature changes

C. Sensitive to physical distortion

D. Sensitive to smooth, mechanical surfaces

C. Sensitive to physical distortion

What is meant by the notion "the output of the cortex can influence the input of the cortex"?

A. Information is transferred unchanged through the brain stem and the thalamus.

B. Neurons of the thalamus and dorsal column are also controlled by cortical input.

C. Somatic sensory system of one side of the brain is related to the other side of the body.

D. Information synapses at the thalamus before proceeding to the neocortex.

B. Neurons of the thalamus and dorsal column are also controlled by cortical input.

What is two-point discrimination?

A. The greatest distance between two points that can be differentiated by the somatic sensory system

B. The smallest distance between two points that can be differentiated by the somatic sensory system

C. The average distance between two points that can be differentiated by the somatic sensory system

D. The distance between two points that cannot be differentiated by the somatic sensory system

B. The smallest distance between two points that can be differentiated by the somatic sensory system

Identify the disorder that causes inability to recognize common objects by feeling them even though they can be recognized by sight or sound.

A. Anosmia

B. Analgesia

C. Astereognosia

D. Agnosia

C. Astereognosia

Primary sensory afferent axons have widely varying diameters, and their size correlates with the type of receptor to which they are attached. Which of these axons are the smallest and the slowest?

A. Proprioceptors of the skeletal muscles

B. Temperature, pain, and itch

C. Pain and temperature

D. Mechanoreceptors of the skin

B. Temperature, pain, and itch

What type of information does the dorsal column medial lemniscal pathway carry?

A. Touch and temperature

B. Touch and vibration

C. Pain and temperature

D. Pain and proprioception

B. Touch and vibration

At what point do the axons of the dorsal column medial lemniscal pathway cross to the opposite side of the CNS?

A. The axons from the cells of the dorsal column nuclei decussate in the medulla.

B. The ascending axons in the dorsal columns cross at the level of the thalamus.

C. The ascending axons in the dorsal columns cross immediately in the spinal cord and ascend to the brain stem contralaterally.

D. The ascending axons in the dorsal columns do not cross.

A. The axons from the cells of the dorsal column nuclei decussate in the medulla.

Which quality of the somatic sensory cortical organization does the distortion of the sensory homunculus reflect?

A. It is a primitive representation of the earlier stages of evolution.

B. The relative size of the cortex that is devoted to each body part varies widely among different individuals.

C. The relative size of the cortex that is devoted to each body part is correlated with the density of the sensory input received from that part.

D. The uneven surface of the cortex disrupts the representation of the body surface.

C. The relative size of the cortex that is devoted to each body part is correlated with the density of the sensory input received from that part.

Which of the following are somatic sensory areas of the parietal lobe?

A. Areas 1 and 2

B. Areas 5 and 7

C. Areas 1, 2, 3a, 3b, 5, and 7

D. Areas 3a and 3b

C. Areas 1, 2, 3a, 3b, 5, and 7

Which of the following is involved in pain pathways in the spinal cord?

A. Acetylcholine

B. Substance P

C. Both b and c

D. GABA

B. Substance P

The painful sensations induced by capsaicin are mediated by

A. serotonin receptors.

B. substance P receptors.

C. habanero receptors.

D. TRPV1.

D. TRPV1.

The receptors through which capsaicin exerts its effects are

A. nicotinic acetylcholine receptors.

B. especially dense in somatosensory cortex.

C. responsive to sudden increases in temperature.

D. opiate receptors.

C. responsive to sudden increases in temperature.

Which of the following secretions promotes swelling at the site of a skin injury?

A. Serotonin

B. Spinal juice

C. Substance P

D. Histamine

D. Histamine

Afferent fibers from the periphery that carry nociceptive information terminate on neurons in the

A. central brainstem.

B. ventral horn cells of the spinal cord.

C. medulla.

D. dorsal horn cells of the spinal cord.

D. dorsal horn cells of the spinal cord.

Small-diameter _______ fibers conduct pain information slowly and adapt slowly.

A. Abeta

B. Aalpha

C. C

D. Adelta

C. C

Information about pain and temperature in the anterolateral system crosses the nervous system at the level of the

A. spinal cord.

B. medulla.

C. pons.

D. cerebral cortex.

A. spinal cord.

What are some differences between the pain and touch pathways? Select all that apply.

A. Diameter of axons is different

B. Their connections to the spinal cord are different

C. They differ in how they transmit information to the brain

D. Different nerve endings in skin

A,B,C,D

Which of the following suppress feelings of pain?

A. Raphe Nuclei

B. VP nucleus

C. Dorsal horn

D. PAG

D. PAG

The responses of thermoreceptors are

A. adaptable.

B. mediated by opiate receptors.

C. always the same, no matter how the stimuli changes.

D. are inhibited by thalamus.

A. adaptable.

Which of the following is a striated muscle?

A. Smooth muscle

B. Cardiac and skeletal muscle

C. Skeletal muscle

D. Cardiac muscle

B. Cardiac and skeletal muscle

The function of a muscle spindle is:

A. to inhibit movement.

B. to initiate voluntary movement.

C. to produce a reflex.

D. to provide information about muscle length.

D. to provide information about muscle length.

Biceps and triceps are

A. muscle fibers.

B. reciprocals.

C. antagonists.

D. synergists.

C. antagonists.

The motor unit is a

A. single motor axon and a single muscle fiber.

B. single motor axon and all the muscle fibers it innervates.

C. collection of axons that travel to the same muscle group.

D. collection of axons that produce the same movement.

B. single motor axon and all the muscle fibers it innervates.

What type of motor neurons ensure that the spindle continues to provide information about muscle length during muscle contraction?

A. Upper motor neurons

B. Alpha motor neurons

C. Spinal interneurons

D. Gamma motor neurons

D. Gamma motor neurons

Which is the first step in the contraction phase of the excitation-contraction coupling?

A. Myosin heads pivot.

B. Action potential occurs at the neuromuscular junction.

C. Nicotinic receptor channels in the sarcolemma open.

D. Ca2+ binds to troponin.

D. Ca2+ binds to troponin.

The monosynaptic stretch reflex arc is

A. what produces the knee jerk reflex.

B. All of these are correct

C. reliant on only one synapse between sensory input and motor neuron output.

D. comprised of Ia axons and alpha motor neurons

B. All of these are correct

Intrafusal muscle fibers are innervated by:

A. alpha motor neurons

B. gamma motor neurons

C. both alpha and gamma motor neurons

D. extrafusal muscle fibers

B. gamma motor neurons

Most of the input to alpha motor neurons comes from:

A. muscle spindles

B. golgi tendon organs

C. other alpha motor neurons

D. interneurons

D. interneurons

Which of the following describes the function and location of Golgi tendon organs?

A. Monitor muscle length, situated in series with muscle fibers

B. Monitor muscle tension, situated in parallel with muscle fibers

C. Monitor muscle length, situated in parallel with muscle

D. Monitor muscle tension, situated in series with muscle fibers

D. Monitor muscle tension, situated in series with muscle fibers

Mirror neurons are especially interesting to researchers because

A. All of these

B. they fire when a monkey sees another monkey (or human) performing a simple movement previously performed by the monkey itself.

C. they appear to trigger specific movements.

D. they might be part of a neural system for empathy.

A. All of these

Which of the following about the primary motor cortex is false?

A. Many M1 cells have directional sensitivity.

B. It occupies a large part of the upper medulla.

C. It is a major source of axons that form the pyramidal tract.

D. Cortical maps of M1 show plasticity, changing with experience

B. It occupies a large part of the upper medulla.

What is the function of lateral pathways with regard to the descending motor pathways?

A. Control the sensory modification of motor control

B. Control the posture and locomotion

C. Control the voluntary movement of distal musculature

D. Control balance of head and shoulders

C. Control the voluntary movement of distal musculature

What is the function of the ventromedial pathways with regard to the descending motor pathways?

A. Control balance of head and shoulders

B. Control the posture and locomotion

C. Control the voluntary movement of distal musculature

D. Relay information from cortex to the cerebellum

B. Control the posture and locomotion

In the hierarchy of motor control, which of the following is a function at the lowest level of control?

A. Memory of sensory information from the past movements

B. Activation of motor neurons that generate goal-directed movement

C. The goal of movement and the best method to achieve this goal

D. Sequences of muscle contraction to accurately achieve the goal

B. Activation of motor neurons that generate goal-directed movement

Consider the motor loop through the basal ganglia. Which of the following is the functional consequence of cortical activation of the striatum?

A. Inhibition of the motor cortex by VL

B. Excitation of the motor cortex by VL

C. Inhibition of VL/VA of thalamus

D. Excitation of the globus pallidus

B. Excitation of the motor cortex by VL