Ablation of the 'somatosensory area I' of the cerebral coex leads to :
D i.e. Loss of tactile localization & two point discrimination Functions & Lesions Somatosensory area I (SI) Primary somatosensory area (SI) is Brodmann's area 1, 2, 3 situated in postcentral gyrus. Ablation of SI would lead to coical pattern of sensory loss. Lesion in this area produce contralateral impairment of: - TouchQ - Sterognosis - Pressure - Barognosis - Proprioception - Cutaneographia - Two point discrimationQ Spinal cord lesion Brainstem lesion Thalamic lesion Coical lesion Five patterns are seen depending Loss of pain & temperature Hemisensory loss of Patients is able to recognize all upon whether there is: on ipsitateral face and all modalitiesQ sensation but localizes them - Complete transaction opposite side of bodyQ. poorly - Hemisection (Lateral medullary - Loss of two point - Central cord section syndrome)Q discriminationQ - Posterior column section sensation) - Sensory inattention
Total loss of pain sensation
Total loss of touch sensation
Loss of tactile localization but not of two point discrimination
Loss of tactile localization and two point discrimination
Loss of tactile localization and two point discrimination