CHAPTER 3 – Notes on information processing

This chapter provides notes on information processing that can be defined as a shift of information in some manner detectable by an observer or a system. In relation to biological sensory systems, it may be a process which describes all that happens in the outer world or in the body, e.g., sudden nature sounds, the changing of the heart rate when rapidly awake or after running, a headache, etc. The information processing can be sequential or in parallel, both of which can be either centralized or distributed. The parallel distributed processing has lately become known under the name of connectionism. The idea of spontaneous order in the brain arising out of decentralized networks of simple units, neurones, was already put forward in the 1950s. Information entropy is the average number of bits needed for data storage or communication. Experiments in several systems demonstrate that real neurones and synapses approach the limits to information transmission set by the spike train or synaptic vesicle entropy. For any kind of neural processing, and particularly for auditory data processing, a basic code is needed. Understanding the neural coding helps to understand the relation between the events in the sensory incoming data from the world or body and the spike trains.