Some thoughts about neural coding and spike trains.
This communication introduces the topic. Foundations: Core concepts: Codings are relations summarized by rules or 'codes'. Special codings are 'neural', 'natural' (in everyday life), 'experimental' (in laboratories), 'conditional' (to partner restrictions). etc. Partial aspects are mechanisms, what partners say about each other, etc. Critical experimental issues: Trains are evaluated by when spikes occur: i.e. as point processes and timings. Trains and point process representations become synonyms. Any code must: (i) be a 'number (rate) code' and an 'interval code'; and (ii) include 'referent, train' covariations involving steady states with overall averages and fluctuations with patterns (dispersions, sequences). Seminal findings. Early data proved trains participated in codings; this is accepted unanimously. Inevitably, though accepted less readily, codings included rates, intervals, averages and patterns. Literature highlights. (1) Confirmed the seminal finding (2.2.) over vast domains; (2) Demonstrated both general and synaptic codings (referents, respectively, sensory, states, etc. and trains in directly connected neurons); (3) Revealed overlap between general and synaptic coding features. Overlap allows train participation in network dynamics; (4) Introduced natural formal contexts. (Point Process Mathematics, Communication. Information and Dynamical Systems Theories); (5) Includes confused opinions: (i) Opposition between rates and intervals; (ii) claims that averages are meaningful but patterns irrelevant. Both, overlooking foundations and evidence, are untenable.
Segundo
J P
JP
Departamento de Biomatemática, Facultad de Clenclas, Montevideo, Uruguay. segundo@neurobio.medsch.ucla.edu
D000200:Action Potentials; D009474:Neurons / Q000502:physiology*; D013569:Synapses / Q000502:physiology