Artificial Chemical Systems Capable of Mimicking Some Elementary Properties of Neurons

Abstract

We describe the photochemical behavior of aqueous solutions containing the Co(CN)63- complex ion and the trans-chalcone form Ct of the 4‘-methoxyflavylium ion (AH+). It is shown that, under the experimental conditions used, the photochemical reaction leading from Ct to AH+ shows an off−on−off behavior upon excitation with a continuous light source or with successive light flashes. The described systems perform as threshold devices and as XOR (eXclusive OR) logic gates. They behave as rudimental artificial neuron-like systems in the sense that their outputs (formation of the AH+ species, with a consequent change in the spectroscopic properties) are the result of an elaboration of two distinct (light) inputs by chemical reactions in solution.