Chapter 15. The Brain and Cranial Nerves
 
Clinical Note: Cranial Reflexes
 


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Cranial Reflexes

Cranial reflexes are reflex arcs that involve the sensory and motor fibers of cranial nerves. Examples of cranial reflexes are discussed in later chapters, and this section will simply provide an overview and general introduction.

Table 15.13 lists representative examples of cranial reflexes and their functions. These reflexes are clinically important because they provide a quick and easy method for observing the condition of cranial nerves and specific nuclei and tracts in the brain.

Cranial somatic reflexes are seldom more complex than the somatic reflexes of the spinal cord. This table includes four somatic reflexes: the corneal reflex, the tympanic reflex, the auditory reflex, and the vestibulo-ocular reflex. These reflexes are often used to check for damage to the cranial nerves or processing centers involved. The brain stem contains many reflex centers that control visceral motor activity. Many of these reflex centers are in the medulla oblongata, and they can direct very complex visceral motor responses to stimuli. These visceral reflexes are essential to the control of respiratory, digestive, and cardiovascular functions. CI:Cranial Nerve Tests







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