Central sulcus
\ Postcentral gyrusParietal lobe
Figure 16.3. Primary somatosensory cortex (S1) is located in the anterior
parietal lobe, immediately posterior to the central sulcus, along the postcen-
tral gyrus.
The discovery of somatosensory body maps was first made in
humans undergoing brain surgery back in the 1930s. The Canadian
neurosurgeon Wilder Penfield (1891-1976) electrically stimulated
various regions of the cerebral cortex in patients on whom he was per-
forming brain surgery. During these surgeries, patients were awake
and able to respond to his questions. By stimulating various parts
of the brain and listening to how patients described their associated
experiences, Penfield characterized the location of the somatosensory
cortex in the parietal lobe and was the first to describe the somatosen-
sory map of the body (Fig. 16.4).
In the somatosensory cortex, the body is represented more or
less according to the how things are anatomically connected on the