We frequently make errors during lapses in our attention, and Weissman et al have now looked at what is happening in the brain during this process. They determined that attentional lapses begin with reduced activity in anterior cingulate and right prefrontal regions that act in a top-down fashion to bias posterior sensory regions in favor of processing task relevant information. This reduced activation occurred before the stimuli used to test attention were presented, and was accompanied by decreasing sensory processing in the inferior occipital cortex. These prefrontal regions seem to modulate how well focused people are in the moment just before they have to perform. The same prefrontal areas implicated in focusing attention before stimulus presentation had greater activation during stimulation following a lapse.
Credit: Nature Neuroscience. The figure, from an accompanying review by Hedden and Gabrieli indicates some of the cortical regions associated with focused and lapsed attention. The arrows indicate reciprocal functional connections between prefrontal and parietal regions, and top-down modulation of occipital sensory regions by the prefrontal cortex. IFG, right inferior frontal gyrus; TPJ, temporal-parietal junction.