19.1 What are the Different Psychological Processes Associated with Attention?
The concepts of arousal, vigilance, and selective attention are all tightly related aspects of our brain’s ability to bring certain pieces of information into conscious awareness and maintain that information over time. When considering selective attention more closely, we start to see the complexities involved in shifting the focus of our awareness, and to appreciate how those shifts involve a number of factors, including the degree to which we make those shifts voluntarily, as well as how those shifts line up with where we’re looking.
19.2 How is Attention Implemented in the Brain?
Attentional mechanisms exist across much of the brain, including brainstem and subcortical structures involved in general arousal, cortical networks for voluntary and reflexive shifts of attention in the dorsal and ventral attention networks, respectively, and the consequences of attentional selection on sensory processing systems as early as the lateral geniculate nucleus and stretching into later, higher-level visual processing regions.
19.3 What Happens to Unattended Information?
Unattended sources of information do not benefit from the same enhanced processing as attended sources, but they are nevertheless processed by the relevant sensory systems in the brain. Historically, attention researchers debated whether the filtering of such information occurred relatively early or late along the sensory pathways. More recent work argues that such distinctions may represent a false dichotomy and that the degree to which attention filters out unattended sources varies dynamically based on factors such as task difficulty and perceptual load.
19.4 What is the Relationship between Attention and Eye Movements?
There is considerable evidence to support the idea that shifts of attention, even when made covertly, engage some of the same perceptual and control systems involved in eye movements. This has led a number of researchers to argue for a premotor theory of attention, in which covert attentional orienting results from planned, but unexecuted saccades. Microstimulation studies in animals show that weak electrical currents applied to a key aspect of the dorsal attentional network—the frontal eye field—result in improved behavioral performance and enhanced neural processing in posterior brain regions, consistent with this premotor theory of attention.
19.5 How Do Clinical Disorders Affect Attentional Function?
A variety of clinical disorders have informed our understanding of the neural basis of attention, including spatial neglect and ADHD. The former provides key insights into the ways in which the brain constructs spatial representations of the world and deploys attentional resources. The latter provides a window into the tight coupling between attentional operations and executive function.
19.6 How Do We Use Executive Functions to Make Decisions and Achieve Goals?
Our ability to plan out and execute behaviors to achieve goals encompasses a group of cognitive processes collectively referred to as executive function. These processes rely heavily on the prefrontal cortex and on dopamine systems in the brain, although the precise neuroanatomical correlates of these functions are still debated. Finally, patients with damage to the frontal lobe and individuals with schizophrenia provide converging evidence concerning the role of the prefrontal cortex in these processes.