Ch.24 Neurologic System Quiz

Which percentage of the population has a dominant left hemisphere, including those who are left-handed?

95% The left hemisphere is dominant in about 95% of people, including those who are left-handed. More than 70%, 75%, and 87% of people have a dominant left hemisphere.

Which type of tremor is common in a patient with cerebral palsy?

Athetosis Athetosis is a type of tremor that occurs in the patient with cerebral palsy and is characterized by slow, twisting, writhing, continuous movements resembling those of a snake or worm. It involves the distal part of the limb more than the proximal part of the limb. Sudden rapid, jerking movements of the limbs, trunks, or face indicate chorea. Chorea is common in the patient with Huntington's disease. Intention tremors are involuntary contractions of the muscles that worsen during voluntary movements and are common in the patient with cerebellar disease or multiple sclerosis. Familial tremor is a type of intention tremor that is common in older adult patients.

Which statement describes decerebrate rigidity?

Back is hyperextended, and the palms are pronated In decerebrate rigidity, the upper extremities of the patient are stiffly extended and adducted. The palms are pronated, the teeth are clenched, and the back is hyperextended. It indicates a lesion in the brainstem at the midbrain or upper pons. In decorticate rigidity, the arms are flexed and adducted (i.e., tight against the thorax), and the legs are extended with plantar flexion. This indicates a hemispheric lesion of the cerebral cortex. In flaccid quadriplegia, complete loss of muscle tone and paralysis of all four extremities occur. It indicates a completely nonfunctional brainstem. Prolonged arching of the back, with the head and heels bent backward, is a symptom of opisthotonos. This indicates meningeal irritation.

Which test helps screen the gross and fine motor coordination skills of a child?

Denver II The Denver II test helps screen the gross and fine motor coordination skills in an infant. This test enables the nurse to assess whether the infant has achieved age-specific developmental motor skills. The nurse performs the Weber test to assess hearing ability of a patient. The Romberg test helps assess the upright postural control in the patient. The nurse uses the heel-to-shin test to check the lower extremity coordination. These tests are performed in older children and adults.

Which muscle tone abnormality would the nurse anticipate in a patient with Guillain-Barré syndrome?

Flaccidity Guillain-Barré syndrome is a polyneuropathy that affects the lower motor neurons. In this condition, there is a decrease in the muscle tone, which leads to flaccidity. Rigidity indicates a constant state of resistance. The patient with Parkinson disease may have muscle rigidity. Upper motor neuron injury causes spasticity in which the muscle tone is increased. The patient with parkinsonism may have cogwheel rigidity, in which increased tone is released intermittently with passive motion.

Which response to the brachioradialis reflex test is documented as normal?

Flexion and supination of the forearm The brachioradialis reflex originates at cervical vertebrae 5 and 6. The nurse holds the patient's thumbs to suspend the forearms in relaxation. The normal response to being struck directly on the forearm is flexion and supination of the forearm. When the stretched tendons of the flexed knee are stroked below the patella, extension of the lower leg is the expected response. This is the quadriceps reflex. Extension of the forearm is expected with the triceps reflex. Dorsiflexion of the toes is an abnormal reaction.

Which lobe of the brain is associated with personality and intellectual functioning?

Frontal The frontal lobe is associated with personality, behavior, emotions, and intellectual functioning. The parietal lobe is associated with the processing of sensory information such as pressure, touch, and pain. The occipital lobe is the primary visual receptor center. The temporal lobe is associated with the functions of hearing, taste, and smell.

Which signs point to a diagnosis of Alzheimer disease? Select all that apply.

Mood swings Disorientation Loss of initiative Alzheimer disease is a neurodegenerative disorder, and the patient may have memory loss because of the death of neurons in the cerebral cortex and subcortical regions. The patient may also have rapid mood swings because of the death of nerve cells. The patient with Alzheimer disease may have disorientation regarding time and place because of damage to the neurons in the cerebrum. The patient may become passive because of a loss of initiative and thus may not participate in any social activities. The patient with multiple sclerosis may have diplopia because of the demyelination of the optic nerve, which is not a pathologic feature of Alzheimer disease. Bradykinesia is the characteristic sign of parkinsonism, but not Alzheimer disease.

Which statement describes the efferent fibers?

Motor neurons carrying impulses to the muscles, organs, and glands A nerve is a bundle of fibers outside the central nervous system (CNS). The efferent fibers are the peripheral motor nerves; these nerves deliver output from the CNS to target organs such as the muscles, organs, and glands. Sensory afferent fibers carry input to the CNS from the receptors. Upper motor neurons are complex descending motor fibers that can influence or modify the lower motor neurons. The pyramidal tract consists of motor nerve fibers that originate in the motor cortex and travel to the brainstem.

Damage to which cranial nerve can cause drooping of the upper eyelids in the patient with myasthenia gravis?

Oculomotor The patient with myasthenia gravis may have ptosis, or drooping eyelids. The oculomotor nerve innervates the eye orbits and controls the movement of the eyes and eyelids. Therefore any damage to cranial nerve III may result in drooping eyelids. Cranial nerve I is the olfactory nerve. It innervates the nose and helps in sense of smell; therefore damage to this nerve may cause anosmia, but not drooping eyelids. The hypoglossal nerve innervates the tongue and controls its movement; damage to this nerve may cause difficulty in swallowing and speech, but not ptosis. The acoustic nerve innervates the ear and mediates the sense of hearing. Damage to this nerve may cause hearing impairment, but not ptosis.

Which test is used to assess for a sensory cortex lesion?

Point location The point location test helps assess the sense of touch, including the ability to localize the sense of touch. If a patient cannot pass this simple test, it could indicate a lesion in the sensory cortex. Cranial nerve VIII, or the vestibulocochlear nerve, transmits hearing impulses from the ear to the brain, and this function is tested by the Weber test. The finger-to-nose and finger-to-finger tests help assess muscle coordination. They help determine whether the patient has cerebellar dysfunction.

The nerve fibers present in the posterior column of the spinal cord carry information about which sensation?

Position and vibration The fibers of the posterior column of the spinal cord conduct the sensations of position, vibration, and finely localized touch. The spinothalamic tract contains sensory fibers that transmit the sensations of temperature, crude or light touch, and pain

The reflex arc consists of which structures? Select all that apply.

Sensory nerve Motor nerve Neuromuscular junction The myotatic reflex is made up of five components. The intact sensory nerve acts as an afferent neuron. The efferent pathway is controlled by an intact motor nerve fiber. The efferent pathway ends in the neuromuscular junction. Apart from these, a functional synapse in the cord and a competent muscle are also present in a reflex arc. A cranial nerve originates in the brain and is not a component of the reflex arc. A nucleus is a brain structure consisting of a relatively compact cluster of neurons. A reflex arc does not involve the brain; it involves the spinal cord and afferent and efferent neurons.

The nurse flashes light into the eyes of a 5-year-old child and observes ocular misalignment and a deviated gaze. Which term would the nurse use to document this finding?

Strabismus Strabismus is a condition in which the eyes are not aligned with each other. It may be caused by extraocular muscle incoordination, which ultimately results in gaze deviation. Nystagmus refers to the involuntary back-and-forth oscillation of the eyeball. Ocular misalignment will not lead to nystagmus in the child. Horner's syndrome occurs because of the disruption of the sympathetic nerves that supply the eyes; it results in ptosis. Disruption of sympathetic nerves does not cause an alteration in the alignment of the eyes. Myasthenia gravis is a chronic condition that weakens various muscles of the body, including the eye muscles. This weakening leads to drooping of the eyelids, but not ocular misalignment.

Which is the major function of the glossopharyngeal nerve?

Swallowing and gagging The glossopharyngeal nerve is cranial nerve IX. Its major motor function is to help in swallowing. The gag reflex, also known as a laryngeal spasm, is a reflex contraction of the back of the throat, evoked by touching the roof of the mouth, the back of the tongue, the area around the tonsils, and the back of the throat; the sensory limb of cranial nerve IX predominantly mediates this reflex. Lateral movement of the eye is controlled by the abducens nerve, or cranial nerve VI. The sensory part of the vagus nerve (cranial nerve X) contributes to the ability to taste. The hypoglossal nerve (cranial nerve XII) controls the muscular movement of the tongue.

Which lobe of the brain is associated with language comprehension?

Temporal Wernicke's area, present in the temporal lobe, is associated with language comprehension. The frontal lobe controls the emotions and behaviors of a patient. The postcentral gyrus of the parietal lobe contains the primary center responsible for sensation. The occipital lobe contains the center that is responsible for vision.

Which cranial nerve would the nurse assess by touching a cotton wisp to the patient's forehead, cheeks, and chin?

V The nurse is testing the sensory function of cranial nerve V (or the trigeminal nerve) by touching a cotton wisp to the patient's face. This is the largest cranial nerve, and it performs sensory functions related to the nose, eyes, tongue, and teeth. This nerve is further divided into ophthalmic, maxillary, and mandibular branches. The patient's light touch sensation is tested by touching a cotton wisp to these designated areas while the patient's eyes are closed. Cranial nerve IV (or the trochlear nerve) is a motor nerve that is connected to the midbrain and controls the eye muscles and turning of the eye. Cranial nerve VI (or the abducens nerve) helps in the lateral movement of the eyes, and cranial nerve VII (or the facial nerve) is responsible for various facial expressions. Because all of these are motor nerves, the light touch sensation test is not required for these cranial nerves.

Which type of basic reflex includes the pupillary response and accommodation?

Visceral There are four types of basic reflexes: the deep tendon reflexes, superficial reflexes, visceral reflexes, and pathologic reflexes. The pupillary response to light and accommodation falls under the category of visceral reflexes. While assessing this reflex, the nurse shines a penlight in the patient's eye and checks if the pupils constrict immediately. The knee jerk falls under the category of a deep tendon reflex. Superficial reflexes include the corneal reflex and the abdominal reflex. Pathologic reflexes are abnormal and may indicate a disease; these reflexes include the Babinski reflex and the Kernig reflex.