attention is typically impaired in Alzheimer's disease. The ability to inhibit inappropriate responses as a component of sustained attention appears to be vulnerable in the mild stages of AD, with selective attention being the most vulnerable and resistant component of attention. Patients with AD showed deficits in tests of visual selective attention, such as Map Search and the Stroop task. Research by Pignatti et al. found that on tasks examining visual selective attention, AD patients’ performance differed significantly from that of healthy elderly controls with longer reaction times and higher error rates, on both quantitative and qualitative levels. In a similar study involving a task in which participants were required to respond to either the detection of the target item or to discriminate between several items on the display, Rizzo et al. found that the AD showed more difficulty compared to the control group on all measures of visual selective attention, and produced more errors in responses. This suggests that mild AD patients showed impairments in terms of visual attention and processing speed, and reduced attention skills correlated strongly with cognitive deficits in specific areas, and cognitive ability as a whole. Reduced performance on attention tests could be attributed to this deficit. Foldi et al. used a multi-target visual cancellation task to examine visual selective attention in patients with AD compared to healthy controls. Researchers found slower performance and completion times compared to those without AD, and this can be seen as a more inefficient and severe form of the attentional processes found in normal aging. Patients with AD scored twice as long on each target or cancellation, irrespective of the type of cancellation, compared to that of the age-matched healthy controls. The control group was also found to slow their search times consistent with a speed-accuracy trade off. That is, when the similarity between targets and distractors increased, and it became more difficult to distinguish the target. However, they maintained detection accuracy with no increase in error rates. This finding suggests, in contrast to patients with AD's performance, that the control group slowed their search only to avoid responses to distractors, and therefore to avoid errors and demonstrate the speed-accuracy trade off. Patients with AD slowed their search as the similarity between target and distractor increased, however they still made more errors and missed targets. This performance did not demonstrate the speed-accuracy trade-off. This suggests that, in AD patients