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bioRxiv · 10.1101/753392

Contralateral Delay Activity is not sensitive to cognitive decline in older adults at risk of Mild Cognitive Impairment.

Farina, F. R.·Pragulbickaite, G.·Bennett, M.·Judd, C.·Walsh, K.·Mitchell, S.·O'Connell, R. G.·Whelan, R.
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Abstract

Contralateral delay activity (CDA) has been proposed as a pre-clinical marker for Mild Cognitive Impairment (MCI). However, existing evidence is limited to one study with a small sample size (n=12 per group). Our aim was to compare CDA amplitudes in a larger sample of low- and high-risk older adult groups (n=35 per group). As expected, behavioural performance decreased as the number of memory items increased, and the low-risk group out-performed the high-risk group. However, we found no differences in CDA amplitudes across groups, indicating that WM capacity increased irrespective of risk-level. These findings suggest that the CDA is not a sensitive marker of MCI risk. More broadly, our results highlight the difficulty in identifying at-risk individuals, particularly as MCI is a heterogeneous, unstable condition. Future research should prioritise longitudinal approaches in order to track the progression of the CDA and its association with cognitive decline in later life.

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Farina, F. R., Pragulbickaite, G., Bennett, M., Judd, C., Walsh, K., Mitchell, S., O'Connell, R. G., Whelan, R.. 2019-09-06. Contralateral Delay Activity is not sensitive to cognitive decline in older adults at risk of Mild Cognitive Impairment.. https://doi.org/10.1101/753392

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