Investigating dynamic neural representations of learning/memory in auditory cortex by sound reconstruction

Songbirds rely on auditory processing of natural communication signals for the rare behavior of vocal learning—the ability to reproduce and recognize vocalizations through an adult model [1,4]. For this project, we obtained depth electrode recordings of local field potential from the caudal medial nidopallium, the songbird equivalent of auditory cortex. Anesthetized songbirds were given novel and familiar auditory objects, and the neural responses elicited by each object were used to predict the auditory objects provided, via a MATLAB-based reconstruction model. [2,3]. We expected that, as the novel objects were repeatedly presented, neural responses to repeats from the later part of stimuli presentation periods would produce better reconstructions (i.e. more similar to the actual objects) than the responses to earlier repeats. The results are inconsistent across birds, with a greater number of repeated presentations associated with worse reconstructions, in support of previously observed passive learning-induced changes in the stimuli-responsive neural networks.