Attentional orienting to mnemonic representations: Reduction of load-sensitive maintenance-related activity in the intraparietal sulcus

• Published in: Neuropsychologia Vol. 50; no. 12; pp. 2805 - 2811
• Main Authors: Trapp, Sabrina, Lepsien, Jöran
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.10.2012; Elsevier
• Subjects: Adult; Attention; Attention - physiology; Biological and medical sciences; Brain - physiology; Brain Mapping; Cues; Female; Functional Neuroimaging; Fundamental and applied biological sciences. Psychology; Human; Humans; Intraparietal sulcus; Learning. Memory; Load; Magnetic Resonance Imaging; Male; Memory; Memory - physiology; Memory, Short-Term - physiology; Parietal Lobe - physiology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Reaction Time; Rehearsal; Storage; Visual working memory; Visual working memory; Load; Intraparietal sulcus; Storage; Rehearsal; Attention; Human; Visual memory; Attention orienting; Central nervous system; Cognition; Representation; Experimental study; Mental load; Encephalon; Perception; Information storage; Parietal lobe; Working memory; Visual attention
• ISSN: 0028-3932; 1873-3514; 1873-3514
• DOI: 10.1016/j.neuropsychologia.2012.08.003

The orienting of attention to internal or mnemonic representations held in visual working memory (VWM) has recently become a field of increasing interest. While a number of studies support the hypothesis that attention to selected representations in VWM reduces memory load, conclusive findings are still missing. In this event-related functional magnetic resonance imaging (fMRI) study, we directly investigated whether attentional orienting to mnemonic representations reduces activity in VWM storage-related areas of the brain. VWM load was manipulated by asking subjects to memorize two, four or six items. A retro-cue during the subsequent delay period asked subjects to attend to just one of these items for a subsequent test. This was compared to trials where subjects were required to continue attending to all items for the subsequent test. Data show reduction of load-sensitive maintenance-related activity along the right intraparietal sulcus (IPS), directly linked to attentional orienting. While activity in the anterior IPS reflected the number of representations in the focus of attention, the activation pattern in the posterior IPS suggested residual activation related to unattended items. This dissociation is in line with a functional subdivision of the right IPS according to attentional and mnemonic properties. ► Attention-related reduction of BOLD response in posterior and anterior IPS. ► Data suggest that attention operates via reduction of unattended representations. ►A confound with expectation/anticipatory effects can be excluded. ► Selection efficiency is facilitated with sequential stimulus presentation. ► Functional subdivision in IPS according to attentional and mnemonic properties.