“…As a mental construct, selective attention (e.g., concentration, focusing, activation, selection) can be distinguished from attention as synthesis (i.e., feature integration; Treisman and Gelade [ 4 ]), attention as effort (Kahneman [ 5 ]), attention as a processing mode (top-down, bottom-up; endogenous or exogenous; parallel, serial, or hybrid (Palmer [ 6 ]; Carrasco [ 7 ]), attention as an individual difference (being attentive or distractible; global or analytic; Murphy [ 8 ], attention as “ stimulus control ” (attending to a stimulus means being controlled by it; e.g., Dinsmoor [ 9 ]), attention as a philosophical construct (choice or free will; awareness or consciousness; James [ 1 ]), and attention as a naive explanation , as in, “I didn’t look carefully after I stopped paying attention”. Attention can also be studied as a neurological construct (a change in single cell responses or in gross recordings like the EEG, VEP, or BOLD response) and as exemplifying underlying neural processes such as gain control and normalization (Desimone and Duncan [ 10 ]; Denison, Carrasco, and Heeger [ 11 ]). All of these usages can be found to apply in studies of vision, visual perception, and visual memory.…”