Alexis is taking part in a visual attention task. She has to press a button every time a target letter appears on the screen. The letters are high contrast, clearly visible, and presented in the same location on the screen. How many potential target letters can Alexis process?

Answer: 8 - 10 per second

Explanation: The visual attention task consists of cognitive operations, that is, observations by which to separate relevant information, in this case the target letters, from irrelevant ones which are therefore irrelevant. It is therefore a set of information, where together they are both relevant and irrelevant, packed to represent the visual scene as a whole, from which only those information we need need to be filtered.

Given that in this case the relevant information / target letters are clearly visible, with a high contrast to the non-target letters, and that the target letters are always in the same place on the screen, the possibility of perception is greater than would be the case if the target letters were not accentuated the way here they are. All this makes it possible to select priorities, i. e the desired information / target letters and to process only such stimuli by looking only at a specific part of the screen. This increases contrast sensitivity because they are high contrast target letters, and by looking at a specific part of the screen where Alexis expects the target letters, to focus only on the contrast. This shortens the reaction time when Alexis sees the target letter, so there are more processed potential target letters that Alexis can process than usual.