Michael Posner and his colleagues argued that in order to shift from one spatial location to another, people must first “disengage” their attention from an initial visual target or location. This process takes time and has other costs associated with it. Posner recognized that attention is a dynamic process and that its focus shifts to different spatial locations or objects according to current behavioral goals and according to the demands of the environment. The metaphor of an “attentional spotlight” was used. A number of distinct stages are required for attention to move from one focus to another according to Posner: first, attention must disengage from its current focus; second, it must move to the new locationand finally, it must then engage at the new location. Neuropsychological and neurophysiological data suggest that these processes may be associated with separate brain areas .
The spotlight and gradient theories In attention research, one prominent theory attempting to explain how visual attention is shifted is the moving-spotlight theory. The primary idea being that attention is like a movable spotlight that is directed towards intended targets, focusing on each target in a serial manner. When information is illuminated by the spotlight, hence attended, processing proceeds in a more efficient manner, directing attention to a particular point and inhibiting input from any stimuli outside of the spotlight. However, when a shift of spatial attention occurs, the spotlight is, in effect, turned off while attention shifts to the next attended location. Attention, however, has also been proposed to adhere to a gradient theory in which attentional resources are given to a region in space rather than a spotlight, so that attentional resources are most concentrated at the center of attentional focus and then decrease the further a stimuli is from the center. Attention in this theory reflects both current and previous attentional allocation, so that attention can build up and decay across more than one attentional fixation over time. This means that time to detect a target may be dependent upon where attention was directed before the target was presented and attention needed to be shifted .
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Michael Posner and his colleagues argued that in order to shift from one spatial location to another, people must first “disengage” their attention from an initial visual target or location. This process takes time and has other costs associated with it. Posner recognized
The spotlight and gradient theories In attention research, one prominent theory attempting to explain how visual attention is shifted is the moving-spotlight theory. The primary idea being
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a dynamic process and that its focus shifts to different spatial locations or objects according to current behavioral goals and according to the demands of the environment. The metaphor of an “attentional spotlight” was used. A number of distinct stages are required for attention to move from one focus to another according to Posner: first, attention must disengage from its current focus; second, it must move to the new locationand finally, it must then engage at the new location. Neuropsychological and neurophysiological data suggest that these processes may be associated with separate brain areas
like a movable spotlight that is directed towards intended targets, focusing on each target in a serial manner. When information is illuminated by the spotlight, hence attended, processing proceeds in a more efficient manner, directing attention to a particular point and inhibiting input from any stimuli outside of the spotlight. However, when a shift of spatial attention occurs, the spotlight is, in effect, turned off while attention shifts to the next attended location. Attention, however, has also been proposed to adhere to a gradient theory in which attentional resources are given to a region in space rather than a spotlight, so that attentional resources are most concentrated at the center of attentional focus and then decrease the further a stimuli is from the center. Attention in this theory reflects both current and previous attentional allocation, so that attention can build up and decay across more than one attentional fixation over time. This means that time to detect a target may be dependent upon where attention was directed before the target was presented and attention needed to be shifted