The nervous system
Most students and many qualified doctors find the examination of the nervous system somewhat daunting. The cerebellum acts as a ‘control centre’ for coordinated movements. In addition, corticocerebellar pathways provide links with information from the cerebral cortex. The recognition and detection of aphasia is extremely important, even when it is a minor deficit, because it reflects disease in localised areas of the dominant hemisphere. Lesions in the left frontal region predominantly affect articulation and fluency; while lesions in the left parieto-occipital area impair reading and left parietal lesions impair several other associative functions, particularly writing. The glossopharyngeal nerve is sensory from the posterior third of the tongue and the mucous membrane of the pharynx. It contains taste fibres from the posterior third of the tongue. The assessment of sensory function starts with the history because symptoms of sensory dysfunction sometimes precede any objective abnormality on clinical testing.