The linkage between map organization structure and single neuron processing in the auditory cortex

Many previous studies demonstrated that the primary sensory cortex has functional clustering structures as a foundation for information processing.  For example, the auditory cortex has the tonotopic map which is a topology preserving mapping of acoustic frequencies. On the other hand, the analytic methods for single neuron study are developing in order to resolve how neurons can encode the information of external stimuli.  In particular, recently dual coding hypothesis which combines rate coding and temporal coding attracts attention as a new rule which resolves this problem, and many physiological results support this hypothesis.
Previous studies, however, hardly clarify how this two concepts link each other. The objective of my study is to demonstrate that application of the method used in the single neuron study against whole auditory cortical neurons can bridge the gap between these concepts, and to find out the mechanism of the hierarchical neural network.

[I] Distribution of mutual information by spike counts and First Spike Latency (a) spike counts  (b) First Spike Latency
[U] a tonotopic map of the auditory cortex