Further evidence of impaired tactile learning after removals of the second somatic sensory projection cortex (SII) in the monkey.

Four rhesus monkeys with bilateral removals of SII and five unoperated monkeys were trained on tests of tactile equivalence, weight discrimination and generalization, tactile discrimination learning (including concurrent learning and serial reversal) and inter-manual transfer of tactile learning. Lesioned animals were impaired on almost all tactile learning tasks and on inter-manual transfer but not on the test of tactile equivalence nor on the propioceptive tasks. The results are considered in the context of previous studies of somatosensory and parietal cortex.