Future directions

In addition to the logical extension of the findings in Chapters 2 through 4 suggested in section 6.1.4, a number of potential experiments could build on the findings reported in this thesis. For example, in Chapter 3 I recorded from anesthetized animals using fairly simple stimulus sets (noise bursts and tones). However, given the existence of a large projection from PLLS in the hearing animal found in Chapter 2, as well as the long-latency bimodal responses to auditory and visual stimulation found in Chapter 4, combined with the known spatial (Stecker et al., 2005) and duration (He et al., 1997) tuning properties of DZ, it would be interesting to record from DZ neurons while presenting auditory

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and visual stimuli that varied in location and duration. Evaluation of the responses of DZ neurons to congruent and incongruent audio-visual stimuli within space could yield insights into the behavioral and functional relevance of the multisensory integration and interactions reported in this thesis.

An extension of the findings of Chapter 5 would be to evaluate the response properties of the visually-responsive neurons in hearing and deaf DZ. Do they respond to visual motion? If so, do they show direction selectivity? What is the receptive field of these neurons? Is there a difference between responses to actual motion and apparent motion? The answers to these questions could provide valuable clues to the missing pieces of the cross-modal puzzle, such as why some sub-regions of sensory-deprived cortices become reorganized and others do not.

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