Dissociations in Visual Attention Deficits among Persons with Mild Cognitive Impairment

ABSTRACT

Impairments in visual attention and visual information processing have been identified as part of the neuropsychological features of Alzheimer's disease (AD), even in its earliest stages. There is increasing recognition that these deficits may be selective rather than global, with some attentional subtypes being more vulnerable than others. The few studies that have investigated attentional deficits in mild cognitive impairment (MCI), a putatively prodromal phase of AD, have not satisfactorily addressed the possible selectivity in attentional deficits in MCI. This study examined potential dissociations in visual attention deficits in MCI using a measure that assesses simple, divided, and selective attention. The results indicated a hierarchy of attentional impairments, with divided attention being the most affected and simple attention the least. Among participants with MCI, 53% showed evidence of impairment in divided attention compared to 19% of controls (OR = 4.81, p < .001). Poorer visual attention was also associated with poorer overall cognitive status. The implications of these findings for early identification of MCI, prevention of functional decline in MCI, and delay/reversal of cognitive degradation in MCI are discussed.

Keywords:

• MCI
• Visual attention
• Visual information processing
• UFOV

ACKNOWLEDGEMENTS

This research was supported by the National Institute on Aging (NIA) through the Alzheimer's Disease Research Center (P50 AG16582), with additional assistance from NIA grants P30 AG022838 and R01 AG021927. NIA's role was limited to approval and funding of the research. The authors are indebted to J. Brockington, MD, D. Clark, MD, H.R. Griffith, PhD, L.E. Harrell, MD, D.C. Marson, JD, PhD, and R. Powers, MD, for their careful diagnostic evaluations of all participants in this ADRC study; to K. Ball, PhD for providing Roybal Center facilities and resources to this project; to K. Belue, P. Forsyth, S. Krzywanski, S. Lanza, and M. Piggott for their recruitment of participants to the ADRC; and to M. Ackerman, B. Hill, S. Lee, and S. Viamonte for their assistance with data collection.

Notes

¹UFOV® is a registered trademark of Visual Awareness, Inc.