Electrophysiological correlates of the Categorization Working Memory Span task in older adults

• Published in: Behavioural brain research 2020-09, Vol.393, p.112809-112809, Article 112809
• Main Authors: Spironelli, Chiara, Carbone, Elena, Borella, Erika
• Format: Article
• Language: English
• Subjects: Cognitive resources; ERPs; Older adults; Recognition potential; Working memory
• ISSN: 0166-4328; 1872-7549
• DOI: 10.1016/j.bbr.2020.112809

•Electrophysiological correlates of a complex Working Memory (WM) task were studied.•Older adults were presented the Categorization Working Memory Span task.•Significant correlations were found between CWMS and another WM task (2-back).•Word RP in CWMS showed greater bilateral amplitude in posterior electrodes.•The better the CWMS performance, the greater the RP amplitude on left sites. Older adults typically show poor performance in tasks assessing working memory (WM), a crucial cognitive mechanism. The present study examined the electrophysiological correlates of a classic complex WM task often used in studies involving older adults, the Categorization Working Memory Span task (CWMS), by means of event-related potentials. Thirty-five healthy, right-handed older adults (64–75 years) were presented the CWMS task while a 38-channel EEG was measured, and the N1, P1, and word recognition potential (RP) were analyzed on four regions of interest (ROIs) of 5 electrodes each. Additionally, late positive components (P200 and P300) were analyzed in midline ROIs of 3 electrodes each. Participants also executed an n-back task (2-back condition) and an objective performance-based task (the Ability to solve Problems in Everyday life [APE]). At a behavioral level, significant correlations were found between the CWMS, the 2-back, and the APE tests. At a physiological level, N1 and word RP showed greater bilateral amplitude in posterior electrodes, but the better the CWMS and the 2-back performance, the greater the RP amplitude on posterior left sites. The CWMS task induced a clear P200 component, but its amplitude was not correlated with participants’ behavioral performance. Altogether, notwithstanding that the bilateral RP pattern elicited by the CWMS is a clear marker of WM processing in older adults, better elderly performers on this complex WM test showed greater left hemisphere dominance to the automatic word RP.