Boosting working memory with accelerated clocks

• Published in: NeuroImage (Orlando, Fla.) Vol. 226; p. 117601
• Main Authors: Thönes, Sven, Arnau, Stefan, Wascher, Edmund, Schneider, Daniel
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-02-2021; Elsevier Limited; Elsevier
• Subjects: Adult; Brain - physiology; CDA; Clocks & watches; Cognition & reasoning; Cognitive ability; EEG; Electroencephalography; Female; Frontal theta; Humans; Investigations; Male; Memory; Memory, Short-Term - physiology; Pacemakers; Perceptions; Posterior alpha; Short term memory; Subjective timepassage; Task engagement; Temporal perception; Theta rhythms; Time perception; Time Perception - physiology; Working memory; Young Adult; CDA; Posterior alpha; Frontal theta; Working memory; Task engagement; Subjective timepassage; Time perception
• ISSN: 1053-8119; 1095-9572
• DOI: 10.1016/j.neuroimage.2020.117601

Our perception of time varies with the degree of cognitive engagement in tasks. The perceived passage of time accelerates while working on demanding tasks, whereas time appears to drag during boring situations. Our experiment aimed at investigating whether this relationship is mutual: Can manipulated announcements of elapsed time systematically affect the attentional resources applied to a cognitive task? We measured behavioral performance and the EEG in a whole report working memory paradigm with six items of different colors that each had to be reported after a short delay period. The 32 participants were informed about the current time after each 20 trials, while the clock was running at either 100% (normal), 120% (fast), or 80% (slow) of normal clock speed depending on the experimental block. The mean number of correctly reported colors per trial was significantly increased in the fast as compared to the slow and normal clock conditions. In the EEG, we focused on neural oscillations during working memory encoding and storage. As an electrophysiological correlate of task engagement, frontal theta power during the storage interval was increased in the fast clock condition. Also, the power of frontal theta oscillations predicted the number of correctly reported colors on a single-trial basis. This shows that a covert manipulation of clock speed can lead to an improvement in cognitive performance, presumably mediated by a higher allocation of attentional resources resulting from an adaptation of the subjective passage of time during an experiment.