Attention as a window into healthy and neuro-degenerate memory processes

In this talk, I present novel evidence that attention and memory share resources and processes, and may be viewed as the same cognitive component. I will show data from healthy young and old adults, and from Mild Cognitive Impaired (MCI) patients performing visual short-term (change detection) and long-term (recognition) memory tasks. I will demonstrate that: (a) changes on objects are better detected when the objects are fixated closer to the centre, but MCI patients do not benefit from it when the semantics of objects is changed, (b) the fixation-related potential associated with a correctly detected change displays a positive distribution over central and frontal area, especially in young adults; and (c) semantic interference in long-term memory - operationalized as the number of scenes of the same semantic category to which participants are exposed to - impairs recognition in control participants (i.e., the more the interference the worst the recognition); but this effect does not emerge in the MCI group. This work suggests that attentional responses and high-level processing of semantic information are proxies to the formation and access to visual memories, and to discriminate between healthy and pathological ageing.