In contrast to selective attention, which enhances pain ratings by increasing sensory gain, emotions triggered by seeing other people's pain did not alter processing in SI-SII (primary and second somatosensory areas), but may have biased the transfer to, and the representation of pain in short-term memory buffers (prefrontal), as well as the affective assignment to this representation (temporal pole). 
These results suggested that the responses were derived from the second somatosensory areas. In conclusion, we could record long-latency responses to air-puff stimulation of the soft palate in the bilateral second somatosensory areas..
All groups showed increased activity in left primary (S1) and bilateral second somatosensory areas, but without response magnitude differences between groups throughout sensorimotor cortex.
Lesion-induced degeneration was combined with immunocytochemistry to study, with electron microscopy, the synaptic connectivity between corticothalamic axon terminals from the first and second somatosensory areas and local circuit neurons of the ipsilateral ventrobasal complex (VB), selectively labelled with an antibody raised against gamma-aminobutyric acid (GABA).
Additional experiments using fluoro-gold and BDA injections provided evidence that the primary somatosensory area is the sole source of layer 5 projections to dorsal Po but that this thalamic region receives convergent layer 6 projections from the primary and second somatosensory areas and from the motor and insular cortices.
Brain electrical source analysis showed that this sequence was explained, with a residual variance below 5%, by a model including two dipoles in the upper bank of the Sylvian fissure of each hemisphere, a frontal dipole close to the midline, and two anterior medial temporal dipoles, thus suggesting a sequential activation of the two second somatosensory areas, anterior cingulate gyrus and the amygdalar nuclei or the hippocampal formations, respectively.
The scalp-recorded N120-P120 appear to correspond to the intracranial N100-P100 and are probably generated bilaterally in the second somatosensory areas.
Injections of horseradish peroxidase (HRP) were used to study the connections of the first and second somatosensory areas (SI and SII) in tree shrews.
Stimulation of the first and second somatosensory areas (SI and SII) was generally less effective in evoking climbing fibre responses than was stimulation of the p.s.g.
The dynamics of habituation in the rostral part of the parietal association region and also in the first and second somatosensory areas was studied by the evoked potentials (EP) method in cats anesthetized with chloralose (80-90 mg/kg) and immobilized with flaxedil.
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