The role of alpha oscillations in deriving and maintaining spatial relations in working memory.
Previous research has demonstrated distinct neural correlates for maintenance of abstract, relational versus concrete, sensory information in working memory (WM). Storage of spatial relations in WM results in suppression of posterior sensory regions, which suggests that sensory information is task-irrelevant when relational representations are maintained in WM. However, the neural mechanisms by which abstract representations are derived from sensory information remain unclear. Here, using electroencephalography, we investigated the role of alpha oscillations in deriving spatial relations from a sensory stimulus and maintaining them in WM. Participants encoded two locations into WM, then after an initial maintenance period, a cue indicated whether to convert the spatial information to another sensory representation or to a relational representation. Results revealed that alpha power increased over posterior electrodes when sensory information was converted to a relational representation, but not when the information was converted to another sensory representation. Further, alpha phase synchrony between posterior and frontal regions increased for relational compared to sensory trials during the maintenance period. These results demonstrate that maintaining spatial relations and locations in WM rely on distinct neural oscillatory patterns.
Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles St., Baltimore, MD, 21218, USA. kara.blacker@jhu.edu.
Kara J
KJ
Blacker
Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles St., Baltimore, MD, 21218, USA.
Akiko
A
Ikkai
Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA.
Balaji M
BM
Lakshmanan
Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles St., Baltimore, MD, 21218, USA.|Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, MD, USA.|Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Joshua B
JB
Ewen
Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles St., Baltimore, MD, 21218, USA.|Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.|F.M. Kirby Center, Kennedy Krieger Institute, Baltimore, MD, USA.
Susan M
SM
Courtney
D000293:Adolescent; D000328:Adult; D000513:Alpha Rhythm; D001307:Auditory Perception / Q000502:physiology; D001921:Brain / Q000502:physiology*; D005260:Female; D006801:Humans; D007600:Judgment / Q000502:physiology; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D065852:Spatial Memory / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult
Abstract; EEG; Phase synchrony; Relational; Working memory