The optimality of perception and cognition: The perception-cognition gap explored

The ability to choose wisely is crucial for our survival. Yet, the received wisdom has been that humans choose irrationally and sub-optimally. This conclusion is largely based on studies in which participants are asked to make choices on the basis of explicit numerical information. Lately, our ability to make such high-level choices has been contrasted with our ability to make low-level (perceptual or perceptuo-motor) choices. Remarkably, we seem able to make near-optimal low-level choices. Taken at face value, the discrepancy gives rise to a perception-cognition gap. The gap implies, for example, that our ancestors were much better at choosing where to put their feet on a rocky ridge (a perceptuo-motor task), compared to choosing which prey to hunt (a cognitive task).The work reported herein probes this gap. There are many differences between literatures showing optimal and sub-optimal performance. The main approach taken here was to match low-and high-level tasks as closely as possible to eliminate such differences. When this is done one finds very little evidence for a perception-cognition gap. Moreover, once the standards of performance assessment of the respective literature are applied to data generated under such conditions it becomes apparent that the cause of the gap seems to lie in the standards themselves. When low-level standards are applied, human choice, whether low-or high-level, looks good. When high-level standards are applied, human choice, whether low-or high-level, looks rather poor. It is easy to see then, that applying high-level standards to high-level tasks, and low-level standards to low-level tasks, will give rise to a " gap " , with no or little actual difference in performance. DECLARATION This work has not previously been accepted in substance for any degree and is not concurrently submitted in candidature for any degree.