Chapter 7 - Discrete Neuroanatomical Substrates for Generating and Updating Temporal Expectations

Abstract

This chapter explains how the neural substrates for temporal expectation differ depending upon the nature of the predictive mechanism being measured. Temporal orienting activated left intraparietal sulcus (IPS) even when the motor effector used to respond to target onset could not be prepared in advance and did so whether the target required a manual or saccadic response and whether this response was left- or right-sided. Spatial and temporal information can also be integrated to predict the time of a certain event at a particular location in space. A variety of different brain regions can therefore represent temporal expectancies, with anatomical localization depending upon the specific characteristics of the task in question. Yet whole-brain functional neuroimaging in humans has allowed a broader picture to be revealed. Although activity in task-specific primary visual cortex varied in line with the hazard function during a visual speeded detection task, thus confirming the electrophysiological data, so too did activity in a variety of higher association areas, comprising SMA and right prefrontal and parietal cortices.