A. Identify four of the 12 cranial nerves (one sensory, one motor, and two mixed

Question

A. Identify four of the 12 cranial nerves (one sensory, one motor, and two mixed (sensory/motor). What are their functions? Where in the brain (in the CNS) and in the body (outside the CNS) do they originate and serve?

B. A viral infection has damaged a patient’s spinothalamic, corticospinal, and posterior column-medial lemniscus tract. What are these pathways or tracts and their functions in the CNS, and what are some signs exhibited by the patient that will help you, as her doctor, to accurately diagnose the problem and the cause of the infection?

Essay#2: (A). What are three differences (3 for each area by comparing them (1 a, b, c; 2 a, b, c; 3 a, b, c)** between the Motor, sensory, and Associated Areas in the brain. Identify two of such areas, and explain their functions (the area) in that region of the brain, and where exactly (the area) is it located in that region of the brain? Section 12.2 Cortex

**(1 a-motor, b-sensory, c-associated; 2 a-motor, b-sensory, c-associated; 3 a-motor, b-sensory, c-associated).

(B).Explain the different “Errors in Refraction” (Sec 15.5), and describe the major structures in the inner ear, their structure, and function (what do they do & how) of the various parts?

Bonus Essay: (A). A viral infection has damaged a patient’s tectospinal tract. What signs of this damage probably helped the physicians diagnose the problem? (B). What are the different classifications of Sensory receptors? Provide and describes two example of each. Since sensory receptors and neurons are involve in reflexes, define and provide the various types? Chapter 13, Section 13.4 &13.6, and Chapter 12.

Explanation / Answer

Part A

Cranial nerve ll is Optic nerve. Its function is to relay the visuals to the visuals cortex of the brain. It is a sensory nerve. It originates in the eyes and end in the Visual cortex located in the occipital lobe of the brain.

Cranial Nerve lll is Occulomotor nerve. Its function is Motor. It controls eye movement. Thi nerve originates from the third nerve nucleus at the level of the superior colliculus in the midbrain and innervates the muscles of the eye and pupil.

Cranial nerve V is Trigeminal nerve. It has 3 brances. Opthalmic and mandibular which are sensory and the third is maxxillary branch which is both sensory and motor. It relays sensory information form the skin of the face and control chewing. So it is a motor and senosry nerve (Mixed). The motor division of the trigeminal nerve derives from the basal plate of the embryonic pons, and the sensory division originates in the cranial neural crest. This nerve innervates the scalp, eyelids, muscles of mastication.

Cranial nerve Vlll is vestibulocochlear nerve. It relays hearing sensation and also helps in maintaining posture. It is a mixed nerve. The cochlear nerve travels away from the cochlea of the inner ear where it starts as the spiral ganglia. The vestibular nerve travels from the vestibular system of the inner ear.

Part B

Spinothalamic tract conveys the affective sensations like need to scratch, need to withdraw if a painful stimuls is felt. The function of corticospinal tract is voluntary motor control of limbs. Posterior column-medial lemniscus tract conveys localized sensations of fine touch, vibration, two-point discrimination, and proprioception (position sense) from the skin and joints. The signs the patient may exhibit is loss of control over limb movements due to corticospinal tract damage, and loss of sensation to touch,vibration dur to the damage of spinothalamic and posterior column medial lemniscus tract. Anasthetic patches can be seen on the skin where there would be no sensation. All the symptoms are consistent with the neurological symptoms exhibited by Herpes Simplex Virus.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.