Rapid associative encoding in basolateral amygdala depends on connections with orbitofrontal cortex.

Michael P Saddoris; Michela Gallagher; Geoffrey Schoenbaum

doi:10.1016/j.neuron.2005.02.018

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Rapid associative encoding in basolateral amygdala depends on connections with orbitofrontal cortex.

Michael P Saddoris·Michela Gallagher·Geoffrey Schoenbaum

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Abstract

Certain goal-directed behaviors depend upon interactions between basolateral amygdala (ABL) and orbitofrontal cortex (OFC). Here we describe neurophysiological evidence of this cooperative function. We recorded from ABL in intact and OFC-lesioned rats during learning of odor discrimination problems and reversals. During learning, rats with ipsilateral OFC lesions exhibited a marked decline in the proportion of ABL neurons that fired differentially during cue sampling both before and after reversal and in the proportion of neurons that reversed odor preference when the odor-outcome associations were reversed. This decline appeared to reflect a loss of rapid flexibility in cue selectivity that characterized activity in intact rats. In addition, lesioned rats had fewer neurons that fired in anticipation of the predicted outcome during a delay period after responding but before outcome delivery. These findings support a role for OFC in facilitating the encoding of information about expected outcomes in ABL.

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Amygdala Animals Association Learning Discrimination Learning Frontal Lobe Male Neural Pathways Neurons Odorants Rats Rats, Long-Evans Journal Article Research Support, U.S. Gov't, P.H.S.

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Michael P Saddoris, Michela Gallagher, Geoffrey Schoenbaum. 2005-04-21. Rapid associative encoding in basolateral amygdala depends on connections with orbitofrontal cortex.. https://doi.org/10.1016/j.neuron.2005.02.018

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