Inter- and Intra-Individual Variability in Non-Linguistic Attention in Aphasia

Abstract

The cognitive skill of attention has previously been found to be impaired in persons with aphasia (PWA) relative to control participants (e.g., Murray, 2012). However, no study to date has examined the degree to which attention fluctuates from day to day in PWA, despite the fact that other neurologically impaired populations, such as Alzheimer’s and Parkinson’s patients, have been found to exhibit a greater degree of day-to-day variability in attention than controls (Burton, Strauss, Hultsch, Moll, & Hunter, 2006). We suggest that day-to-day intra-individual variability (DTD-IIV) in attention is an important area of investigation in aphasia, and furthermore that inter-individual differences in DTD-IIV in attention may be critical in reliably predicting treatment outcomes. The expectation that an individual will improve her skills over time as a function of treatment is based on the assumption that she is able to pay attention consistently during each session. If an individual is in fact able to attend consistently each day, this assumption is fair; however, if her attention fluctuates from day to day, it seems unlikely that she will show rapid or steady improvement. With this in mind, the goal of this study was to systematically assess five types of non-linguistic attention in both PWA and control participants, using a novel computerized task and repeated sampling design. Analyses examined reaction times as well as DTD-IIV