Identifying Multisensory Dendritic Stimulus Processors

Functional identification is a key methodology for uncovering the logic of neuroinformation processing of brain circuits. For neural circuits modeling sensory systems as dynamical systems, the complexity of the identification algorithm largely depends on the number of stimuli used. Neurons in these circuits consist of dendritic stimulus processors modeling the signal processing in the dendritric tree and biological spike generators modeling the spiking mechanism at the axon hillock. Here, we review the identification of multi-sensory spatio-temporal dendritic stimulus processors that arise in the encoding of auditory scenes, color visual fields, and the mixing of auditory scenes and natural visual fields. We demonstrate the fundamental duality between the identification of the dendritic stimulus processor of a single neuron and the decoding of stimuli encoded by a population of neurons with a bank of dendritic stimulus processors. The duality enables us to reconstruct the originally encoded stimuli from all the generated spikes by using the identified neural circuit. The reconstruction leads to a simple and intuitive evaluation of the identified dendritic stimulus processors in the space of stimuli.