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Neural mechanisms behind shifts of attention – Wikipedia, the free encyclopedia.

When we pay attention to something, we’re better able to attend to it. But at the same time, that means that we aren’t as good at attending to other regions. Additionally, once we stop paying attention to something, we’re not as likely to return to the original focus.
We shift our attention from one things to another. Though we look at different things, we focus our attention on one thing at a time, the shifts facilitating the processing of multiple streams of input. Attention may then be like a spotlight: We move our attention around until we focus on something. However, we turn the spotlight off when we move the attention again.

Posner suggested that for attention to be moved to another location, attention is first disengaged, then the attention is physically shifted, and finally attention is engaged in a new place. Whether the neural systems that aid this process overlap significantly is under debate.

Covert attention shifts occur when the attention is moved differently than the eyes. Some people with mid-brain damage aren’t able to move their eyes voluntarily, but they can still move their attention, which implies that areas in the mid-brain are involved in overt shifts in attention. The superior colliculus is associated with eye movements, with overt shifts of attention.

But there is a lot of evidence that there are multiple areas involved in both covert and overt attention shifts: frontal, parietal and temporal lobes. fMri technology shows overlap in areas of activation for the two kinds of attention shifts. It was found that a there may be an area specific to covert attention shifts, the right dorsolateral cortex, which has to do with voluntary attention shifts and working memory. There is a question whether all covert attention shifts involve such activation, or perhaps it is an effect of the task that was given to the subjects. And there is a larger activation for overt attention shifts, which may be explained by the need for eye movements.
Not all shifts of attention are voluntary. Different activation patterns are observed for voluntary and involuntary shifts.¬† The areas of the brain to do with voluntary attention, the dorsal posterior parietal and the frontal cortext region, are believed to integrate previous “knowledge, expections and goals to voluntarily decide where to shift attention.” There are multiple areas of the brain that are involved in attention shifts, but the amount of overlap between voluntary and involuntary shifts is not well established. One thing that the research implies is that¬† working memory is voluntarily activated. Attention can be guided top-down or bottom-up, and various areas of the brain are largely involved in different attention shifting tasks.

Different types of attention shifts correspond to different areas of the brain, yet many of these areas overlap. The amount of activation differs. Neuroscience may still offer much in terms of understanding the neuromechanisms behind shifts of attention.