The amygdala's role in processing cognitive and affective information conveyed by communication sounds is not well studied. In particular, the pattern and spatial organization of activity in the lateral nucleus (LN) of the amygdala, which may contribute to motivating specific responses to these stimuli, is not known. This application is aimed at demonstrating the neurophysiological and neuroanatomical correlates of the amygdala's contribution to the recognition of affect and the meaning of communication sounds. I propose to investigate the selectivity of amygdala neurons for species-specific audiovocal communication sounds in the spatial and temporal domains in the LN of the mustached bat. Diversity and richness in the repertoire of communication sounds or """"""""calls"""""""" is expected to drive neurons of the LN to different degrees and in different locations. In addition, the complexity of the acoustic stimulus may determine the complexity of temporal response patterns within the amygdala. Microelectrodes will be used to record the activity of single neurons and neuronal ensembles in response to social call presentations. In addition to histological verification of recording sites, magnetic resonance imaging will enable in-vivo verification of the precise location of recording sites early on in our chronic preparation. This research will constitute an important step toward understanding normal and disordered auditory processing of social calls in the amygdala. The amygdala is interconnected with both the auditory cortex and thalamus and also projects to the inferior colliculus. Therefore, it is critical to understand how sounds are represented and processed here in order to fully comprehend the functioning of the auditory structures and any auditory prosthetic devices that may be implanted therein.
The amygdala is a brain structure that is known to play an important role in social communication in many animals ranging from mice to humans. Specifically, the amygdala may help a person to have an appropriate, adaptive response to vocal expressions of emotion. Understanding how the amygdala is organized to serve this purpose will lead to a better understanding of several communication disorders where auditory memory and perception are impaired.
