Walsh & Hoyt: Tests of Cutaneous Sensation

The sense of touch may be easily tested with a small wisp of cotton or the edge of a tissue. One may also use a light brush of the fingertips against the skin of the face. If reliability is in doubt, the patient should be asked to close the eyes and then indicate each touch. Although the most sensitive test is to compare the sense of light touch on one side with the other, this method frequently leads to spurious information. The nasal mucosa is highly sensitive to the lightest touch, and the comparison of the ""nasal tickle"" response may also be useful. Because the gingiva is also innervated by the trigeminal nerve, testing inside the mouth may produce useful information. In particular, patients with nonorganic sensory loss often do not note sensory changes inside the mouth. One may use the sharp end of a broken tongue blade to check gingival sensation, again comparing one side with the other. It is imperative to check all three branches of the trigeminal nerve bilaterally, as they may be differentially affected, depending on the location of the lesion