CRANIAL NERVES

Cranial nerve ll (Optic)

Cranial nerve II (optic) is responsible for visual acuity and visual fields. Asking the client to read an eye chart is part of assessing cranial nerve II, the optic cranial nerve.

Glasgow Coma Scale

A score of 8 or lower usually indicates coma. The total score will range from 3 to 15; the higher the number, the better

Cranial nerve Vlll (Vestibulocochlear)

CN VIII is the acoustic nerve. It has to do with hearing, air and bone conduction, and balance. Assessing cranial nerve VIII (acoustic) would involve using the whisper or watch-tick test to evaluate hearing

Cranial nerve X (Vagus)

CN X is the vagus nerve and has to do with the gag reflex, laryngeal hoarseness, swallowing ability, and the symmetrical rise of the uvula and soft palate

Cranial nerve Xll (Hypoglossal)

Cranial nerve XII, the hypoglossal nerve, controls tongue movements involved in swallowing and speech. The tongue should be midline, symmetrical, and free from tremors and fasciculations

Sympathetic Effects

Decreased peristalsis and relaxed muscular walls urinary bladder. increased B/P, HR, RR, conversion of liver glycogen to glucose, increased sweat. Dilated pupils, dilated bronchioles, dilated heart and skeletal muscle. Contracted pilomotor muscle, thick, viscid saliva. Secretion of epinephrine and norepinephrine.

Decerebrate posturing

Extremities are stiff and ridged, hands flexed outward, feet plantar flexed. MORE SERIOUS than decorticate. Indicates damage of the upper brain stem. Damage to the midbrain causes decerebrate posturing that's characterized by abnormal extension in response to painful stimuli

Cranial nerve Xl (Accessory)

Having the client elevate the shoulders with and without resistance is part of assessing cranial nerve XI, the spinal accessory cranial nerve that innervates the sternocleidomastoid muscle and the upper portion of the trapezius muscle

Cerebrum

Thinking and reasoning problems are the result of injury to the cerebrum. To assess cerebral function, the nurse should ask about the client's level of consciousness, orientation, memory, and other aspects of mental status.

Parasympathetic stimulation

Results in constricted pupils, constricted bronchioles, increased peristaltic movement, and contracted muscular walls of the urinary bladder, increased secretions of stomach, intestine and pancreas. DECREASED heart rate, B/P, RR. Thin, watery saliva.

Cranial nerve I (olfactory )

SMELL. The nurse would ask the client to smell and identify a nonirritating, aromatic odor when testing the function of cranial nerve I, the olfactory cranial nerve.

Cranial nerve Vl (Abducens)

The abducent nerves (VI) are responsible for lateral extraocular movements. Cranial nerve VI controls lateral eye movement.

Arachnoid

The arachnoid is the middle membrane and is responsible for the production of cerespinal fluid

Hypothalamus

The body's thermostat is located in the hypothalamus; therefore, injury to that area can cause problems with body temperature control

Cerebellum

The cerebellum, which is located behind and below the cerebrum, controls and coordinates muscle movement. Questions about coordination help her assess cerebellar function

Dura Mater

The dura mater is the outermost layer and covers the brain and spinal cord.

Pia Mater

The pia mater is the innermost membrane that hugs the brain closely and extends into every fold of the brain's surface

Decorticate posturing

Arms are flexed, fists are clenched, legs are internally rotated and feet are plantar flexed. With damage to the diencephalon or cortex, abnormal flexion (decorticate posturing) occurs when a painful stimulus is applied.

Cranial nerve Vll (Facial)

The facial (VII) nerve controls facial expression and muscle movement. The facial (VII) nerve is responsible for salivation, tearing, taste, and sensation in the ear. An appropriate assessment technique for this cranial nerve would include observing for symmetry while the patient performs facial movements: smiles, whistles, elevates eyebrows, and frowns

Frontal Lobe

The frontal lobe, the largest lobe, controls concentration, abstract thought, information storage or memory, and motor function. The frontal lobe influences personality, judgment, abstract reasoning, social behavior, language expression, and movement. Written speech, Motor speech (Broca area)

Cranial nerve lX (Glossopharyngeal)

The glossopharyngeal nerve (IX) is responsible for swallowing movements and throat sensations. It's also responsible for taste in the posterior third of the tongue. Swallowing is a motor function of cranial nerves IX and X

Flaccidity

The most ominous motor response is flaccidity, when the client makes no motor response. Damage to the medulla results in flaccidity

Occipital Lobe

The occipital lobe is responsible for visual interpretation.

Cranial nerve lll (Oculomotor)

The oculomotor (III) cranial nerve is responsible for the muscles that move the eye and lid, pupillary constriction, and lens accommodation. PERRLA

Parietal Lobe

The parietal lobe interprets and integrates sensations, including pain, temperature, and touch; it also interprets size, shape, distance, and texture. The parietal lobe contains the primary sensory cortex, and is essential to an individual's awareness of the body in space, as well as orientation in space and spatial relations. The parietal lobe contains the primary sensory cortex, which analyzes sensory information and relays interpretation to the thalamus and other cortical areas.

Temporal Lobe

The temporal lobe regulates memory. The temporal lobe plays the most dominant role of any area of the cortex in cerebration. The temporal lobe controls hearing, speech comprehension (Wernicke area), and storage and memory recall (although memory recall is also stored throughout the brain).

Cranial nerve lV (Trochlear)

The trochlear nerve (IV) is responsible for extraocular movement (inferior medial). The trochlear nerve coordinates the muscles that move the eye

Meninges

The term "meninges" describes the fibrous connective tissue that covers the brain and spinal cord. The meninges have three layers, the dura mater, arachnoid, and pia mater.

Cranial nerve V (Trigeminal)

The trigeminal (V) cranial nerve is responsible for facial sensation, corneal reflex, and mastication. The motor function of cranial nerve V is chewing.