Radiotelemetered activity from the amygdala during social interactions in the monkey

Electrical activity from the amygdaloid nucleus in freely moving monkeys ( Cercopithecus aethiops) during social interactions and alone were recorded via radiotelemetry. Spectral analysis of amygdaloid activity revealed highest power outputs occurred during behaviors related to sexual and aggressive interactions and the lowest with the tension-reducing behavior of grooming. Power output was not directly related to motor activity. These results suggest that amygdaloid activity is related to the emotional significance and degree of ambiguity of an interaction. It is hypothesized that at least two separate afferent systems, one for low frequencies and the other for fast frequencies, may be correlated with different behavioral events.