NEURONS IN HUMAN TEMPORAL CORTEX ACTIVE WITH VERBAL ASSOCIATIVE LEARNING

In neuronal activity recorded from human middle temporal gyms during l earning of associations between word pairs, a population was identifie d that had greater activity for associations that were learned rapidly during initial encoding compared to those learned slowly or not at al l by an individual subject. This population can be separated from othe r neurons by the combination of inhibition during word reading when no learning is required and excitation during recent memory for words. T hese neurons are present in both hemispheres, predominately in deeper layers of cortex. During initial encoding, the increased activity appe ars at presentation of all word pairs but persists for several seconds only for the rapidly learned pairs, likely reflecting rehersal of ite ms being learned. Human associative learning is related to activity of this specific population of ''association'' neurons, identified here for the first time. (C) 1998 Academic Press.