Somatosensory

Cortical somatosensory modalities 6

• stereognosis: the ability to understand or recognize an object by touch; deficit: astereognosis

• graphesthesia: the ability to recognize a number or letter traced on the skin; deficit: agraphesthesia

• two-point discrimination: two stimuli applied at the same time are felt as separate

• somatosensory extinction: inability to perceive two simultaneous somatosensory stimuli

• autotopagnosia: inability of patient to point to a part of the body, despite being able to recognize and name that body part; few reported cases, lesions involving left posterior parietal cortex