Abstract

This chapter reviews formal models of the decision process in humans and other primates, and discusses divergent accounts of how attention might intervene to bias or facilitate judgements about sensory stimuli. The review covers established decision-theoretic models, such as signal detection theory and serial sampling models, and other computational accounts that draw upon psychophysical and neurobiological mechanisms of early vision. It considers whether such decisions are limited by attentional capacity, or by noise, as suggested by normative models of choice. The authors revisit a debate concerning whether attention acts to boost inputs, enhance activity, or reduce noise. Finally, the authors consider the relationship between attention and expectation in perceptual decision-making.