Amygdalar and hippocampal neuron responses related to recognition and memory in monkey

This chapter initially characterizes, in several ways, the responses of amygdalar and hippocampal neurons to affective sensory stimuli. Amygdalar and hippocampal neuronal responses to stimuli that are considered to be biologically significant are studied in various behavioral tasks that involve the discrimination of different rewarding and aversive stimuli. Some neurons are also tested by changing the affective significance of the stimuli presented. Comparison of amygdalar and hippocampal neuronal responsiveness to affective sensory stimuli elucidates differences in the functions of these two structures. Functional connections between the association cortex and medial temporal lobe (and the hypothalamus), which underlie amygdalar and hippocampal responsiveness to complex sensory stimuli, are investigated by analyzing neuronal response changes during reversible disconnection of the inferotemporal cortex from the amygdala, or disconnection of the amygdala from the hypothalamus, by cooling the inferotemporal cortex or the amygdale. Hippocampal neurons are analyzed in more detail by introducing a spatial factor. The chapter also discusses the experiments on monkey hippocampal neurons were recorded during performance of a spatial moving task.