The derivation of nerve signals from contrast flash data. A re-analysis.

This paper presents a new analysis of the contrast flash data of Alpern et al. (1970a--d). It was prompted by the criticism of Wandell (1976) who pointed out that Alpern et al., main conclusion, i.e, that the inhibitory signal N (phi) elicited by the contrast flash (phi) takes the form (formula: see text), would imply an unrealistic excitatory photo response. The present analysis shows the data to be consistent with an inhibitory signal of the form (formula: see text).