"Attention is the behavioral and cognitive process of selectively concentrating on one aspect of the environment while ignoring other things. Attention has also been referred to as the allocation of processing resources.
Attention is one of the most intensely studied topics within psychology, cognitive neuroscience and neuropsychology. Attention remains a major area of investigation within education, psychology, neuroscience and neuropsychology. Areas of active investigation involve determining the source of the signals that generate attention, the effects of these signals on the tuning properties of sensory neurons, and the relationship between attention and other behavioral and cognitive processes like working memory and vigilance. A relatively new body of research, which expands upon earlier research within neuropsychology, is investigating the diagnostic symptoms associated with traumatic brain injuries and their effects on attention. Attention also has variational differences among differing cultures."
"Researchers have described two different aspects of how the mind comes to attend to items present in the environment.
The first aspect is called bottom-up processing, also known as stimulus-driven attention or exogenous attention. These describe attentional processing which is driven by the properties of the objects themselves. Some processes, such as motion or a sudden loud noise, can attract our attention in a pre-conscious, or non-volitional way. We attend to them whether we want to or not. These aspects of attention are thought to involve parietal and temporal cortices, as well as the brainstem.
The second aspect is called top-down processing, also known as goal-driven, endogenous attention, attentional control or executive attention. This aspect of our attentional orienting is under the control of the person who is attending. It is mediated primarily by the frontal cortex and basal ganglia as one of the executive functions. Research has shown that it is related to other aspects of the executive functions, such as working memory, and conflict resolution and inhibition."
"There are studies that suggest the mechanisms of overt and covert orienting may not be as separate as previously believed. This is due to the fact that central mechanisms that may control covert orienting, such as the parietal lobe also receive input from subcortical centres involved in overt orienting. General theories of attention actively assume bottom-up (covert) processes and top-down (overt) processes converge on a common neural architecture. For example, if individuals attend to the right hand corner field of view, movement of the eyes in that direction may have to be actively suppressed."