The clinical neurological examination permits functional assessments within several domains. In the first domain, the clinician assesses mental status, which is defined according to levels of consciousness, ability to pay attention, accurate orientation with respect to time and place, comprehension and expression of language, learning and memory, general cognitive abilities (e.g., calculation, wealth of knowledge, comprehesion of abstract concepts, correct interpretation of sensory stimuli, and the ability to perform learned motor tasks), emotional state, and finally the content, coherence, and organization of thoughts.

Also assessed are those functions subserved by the cranial nerves. These include the olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, spinal accessory, and hypoglossal nerves, which subserve seonsory, motor, and autonomic (i.e., parasympathetic and sympathetic) function.

Assessments of the motor systems may begin with examinations of the muscles themselves. Also at issue are the functional states of the lower and upper motor neurons along with the structures that regulate their function (e.g., basal nuclei and cerebellum). This is ascertained through investigation of muscular coordination and posture.

Functional characteristics of the sensory systems are assessed according to the ability of the patient to detect (and sometimes interpret) specific stimuli affecting regions of the body other than those innervated by the cranial nerves. Because neural pathways used in the processing of particular stimuli are well characterized, the responses of patients to certain systematically applied stimuli may aid in the localization of lesions within the nervous system.

For clinical purposes, reflexes refer to the reliable stereotyped motoric reponses generated following the delivery of specific stimuli in neurologically intact persons. Of concern in this context are the reflexes subserved by the noncranial peripheral nerves, with deep tendon and cutaneous reflexes being the target of greatest scrutiny.