An abnormality of somatosensory evoked potentials (SSEP), i.e., of the electrical signals of sensation going from the body to the brain in response to a defined stimulus. Recording electrodes are placed over the scalp, spine, and peripheral nerves proximal to the stimulation site. Clinical studies generally use electrical stimulation of peripheral nerves to elicit potentials. SSEP testing determines whether peripheral sensory nerves are able to transmit sensory information like pain, temperature, and touch to the brain. Abnormal SSEPs can result from dysfunction at the level of the peripheral nerve, plexus, spinal root, spinal cord, brain stem, thalamocortical projections, or primary somatosensory cortex. [from
HPO]