Neural mechanisms of eye gaze processing as a function of emotional expression and working memory load

AbstractThe neural mechanisms associated with the limited capacity of working memory has long been studied, but it is still unclear how the brain maintains the fidelity of representations in working memory. Here, an orientation recall task for estimating the precision of visual working memory was performed both inside and outside an fMRI scanner. Results showed that the trial-by-trial recall error (in radians) was correlated with delay period activity in the lateral occipital complex (LOC) during working memory maintenance, regardless of the memory load. Moreover, delay activity in LOC also correlated with the individual participant’s precision of working memory from a separate behavioral experiment held two weeks prior. Furthermore, a region within the prefrontal cortex, the inferior frontal junction (IFJ), exhibited greater functional connectivity with LOC when the working memory load increased. Together, our findings provide unique evidence that the LOC supports visual working memory precision, while communication between the IFJ and LOC varys with visual working memory load.

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Working memory availability affects neural indices of distractor processing during visual search

10.1101/295378 ◽

2018 ◽

Cited By ~ 1

Author(s):

Dion T. Henare ◽

Jude Buckley ◽

Paul M. Corballis

Keyword(s):

Working Memory ◽

Visual Search ◽

Memory Load ◽

Individual Performance ◽

Event Related Potential ◽

Neural Mechanisms ◽

Human Cognition ◽

Working Memory Load ◽

Distractor Processing ◽

Selective Processing

AbstractWorking memory and selective attention are traditionally viewed as distinct processes in human cognition. However, increasing research demonstrates significant overlap between these constructs such that as working memory availability decreases, individuals perform worse on attention-based tasks. To date, the neural mechanisms involved in this interaction are unknown. We measured three candidate lateralized event-related potential components (N2pc, Ptc, and SPCN) to observe the effects of increased working memory load on selective processing of targets and distractors. We found that increased working memory load impaired the processing of distractors, but not targets, and this was reflected in attentuation of the Ptc to distractors. We also found that individual performance on the task is related to the neural response to both targets and distractors. This study suggests that working memory availability impacts individuals’ ability to disengage from irrelevant stimuli, and that individual differences in visual search ability under load are related to both target and distractor processing.

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Visual Search Facilitation in Repeated Displays Depends on Visuospatial Working Memory

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000125 ◽

2012 ◽

Vol 59 (1) ◽

pp. 47-54 ◽

Cited By ~ 16

Author(s):

Angela A. Manginelli ◽

Franziska Geringswald ◽

Stefan Pollmann

Keyword(s):

Working Memory ◽

Visual Search ◽

Control Experiment ◽

Memory Load ◽

Contextual Cueing ◽

Long Term Memory ◽

Visuospatial Working Memory ◽

Working Memory Load ◽

Memory Resources

When distractor configurations are repeated over time, visual search becomes more efficient, even if participants are unaware of the repetition. This contextual cueing is a form of incidental, implicit learning. One might therefore expect that contextual cueing does not (or only minimally) rely on working memory resources. This, however, is debated in the literature. We investigated contextual cueing under either a visuospatial or a nonspatial (color) visual working memory load. We found that contextual cueing was disrupted by the concurrent visuospatial, but not by the color working memory load. A control experiment ruled out that unspecific attentional factors of the dual-task situation disrupted contextual cueing. Visuospatial working memory may be needed to match current display items with long-term memory traces of previously learned displays.

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