VAP 13.14-13.19

Damage to the pyramidal cells of the cerebral cortex would directly affect ANSWER: voluntary motor activity. perception of pain. hearing. both perception of pain and hearing. sight.

a

A fast-adapting tactile receptor that monitors movements across the body surface is a ANSWER: root hair plexus. Ruffini corpuscle. tactile (Meissner) corpuscle. lamellated corpuscle. tactile (Merkel) disc.

a

Based on the motor homunculus, which of the following body regions has the largest motor units? ANSWER: back hands tongue larynx face

a

The area of the motor cortex that is devoted to a particular region of the body is proportional to the ANSWER: number of motor units in that region. size of the nerves that serve the area of the body. distance of the body area from the brain. number of sensory receptors in the area of the body. size of the body area.

a

Which ascending tract carries the sensations for fine touch and vibration? ANSWER: posterior (dorsal) column spinothalamic corticospinal corticobulbar both posterior (dorsal) column and spinothalamic

a

A ________ receptor always sends a signal, but the rate of action potentials changes as a result of stimulation. ANSWER: phasic tonic mechanoreceptor nociceptor all of the above

b

In order for a sensation to become a perception, ANSWER: it must be received by the pulvinar nucleus of the thalamus. it must be received by the somatosensory cortex. the other senses must be silent. it must arrive over fast-conducting nerve fibers. the individual must vocalize about it.

b

We can localize sensations that originate in different areas of the body because ANSWER: incoming sensory information is first processed by the thalamus. sensory neurons from specific body regions project to specific cortical regions. sensory neurons carry only one modality. different types of sensory receptors produce action potentials of different sizes and shapes. of the many types of tactile receptors.

b

Complex motor activities such as riding a bicycle ANSWER: only require neural processing at the level of the cerebrum. with practice, involve little input from the brain. require the coordinated activity of several regions of the brain. usually escape notice by the cerebellum. are largely controlled at the level of the spinal cord.

c

Parkinson disease is the result of ANSWER: weak response of the red nuclei of the midbrain. hyperactivity of the limbic system. inadequate production of dopamine by substantia nigra neurons. decreased levels of acetylcholine from neurons in the substantia nigra. inadequate production of GABA by neurons in the basal nuclei.

c

The spinal tract that relays information concerning pain and temperature to the CNS is the ANSWER: fasciculus cuneatus. anterior spinothalamic. lateral spinothalamic. posterior spinocerebellar. fasciculus gracilis.

c

Your uncle was just diagnosed with a heart attack. One of his major symptoms is left arm pain. You are not surprised because you are familiar with the phenomenon of ANSWER: neurogenic pain. phantom pain. referred pain. somatic pain. psychogenic pain.

c

Damage to the substantia nigra causes a decrease in the neurotransmitter dopamine. This causes a gradual, generalized increase in muscle tone, which is the main symptom of ANSWER: rabies. Alzheimer disease. myasthenia gravis. Parkinson disease. tetanus.

d

Sensory encoding of the perceived location of a stimulus depends on ANSWER: which labeled line is active. the frequency of action potentials. the specific sensitivity of the peripheral receptor. the specific location of the cortical neuron that is stimulated. both the frequency of action potentials and which labeled line is active.

d

Increased production and release of acetylcholine by the neurons of the cerebral nuclei would result in ANSWER: flaccid paralysis. fewer action potentials along the corticospinal tracts. muscular atrophy. decreased activity of upper motor neurons. spastic, uncontrolled muscle contractions.

e

Motor neurons whose cell bodies are within the spinal cord are called ________ neurons. ANSWER: upper motor somesthetic postganglionic preganglionic lower motor

e

The cerebellum relies on information from ANSWER: the eyes. the inner ear as movements are under way. proprioceptive sensations. motor commands from upper motor neurons. all of the above

e

The descending spinal tract that crosses to the opposite side of the body within the cord is the ________ tract. ANSWER: vestibulospinal lateral corticospinal rubrospinal reticulospinal corticospinal

e

Which of the following kinds of information do fine-touch and light-pressure mechanoreceptors provide? ANSWER: location of the stimulus. shape of the stimulus. texture of the stimulus. movement of the stimulus. all of the above

e