Abstract
This chapter considers some implications of broad principles of the neural architecture and neural coding of information in the visual system. J. H Reynolds and R. Desimone suggest that attentional shrinkage of receptive fields around attended objects serves to solve the binding problem. Attention serves to optimise the veridicality of responses of cells involved in coding complex properties of stimuli. Neurophysiological studies have shown that attentional modulation and changes in the luminance of a stimulus can create identical modulations of firing rates. Modulating the strength of a stimulus by altering its perceived brightness is only one function of attention. Independent evidence that a role of attention is to prevent informational overload comes from the case of hallucinogens. A possible mechanism for how psilocybin affects attentional tracking can be identified by looking closer at how this chemical generates drug-induced hallucinations.