Which of the following has small representation in somatosensory area of cerebral coex ?
Ans. is 'd' i.e., Trunk A distinct topographic represention of the body can be demonstrated in somatosensory area-I. Each side of the coex receives sensory information from the opposite side of the body only (contralateral representation). The body is represented upside down (veical) in the postcentral gyms, i.e. the face is represented at the foot of the gyrus whereas the legs and feet are represented at the top extending on the medial surface. Some pas of body like face (especially lips, tongue) and fingers have a propoionately large representation than the other areas like the trunk. The coical representation of the pa of the body is propoionate to its innervation density (number of sensory receptors) rather than its size.
Lips
Thumb/fingers
Tongue
Trunk