Format

Send to

Choose Destination
Cereb Cortex. 2015 Dec;25(12):4697-703. doi: 10.1093/cercor/bhu153. Epub 2014 Jul 10.

Electrophysiological Evidence for a Sensory Recruitment Model of Somatosensory Working Memory.

Author information

1
Department of Psychology, Birkbeck College, University of London, London WC1E 7HX, UK.

Abstract

Sensory recruitment models of working memory assume that information storage is mediated by the same cortical areas that are responsible for the perceptual processing of sensory signals. To test this assumption, we measured somatosensory event-related brain potentials (ERPs) during a tactile delayed match-to-sample task. Participants memorized a tactile sample set at one task-relevant hand to compare it with a subsequent test set on the same hand. During the retention period, a sustained negativity (tactile contralateral delay activity, tCDA) was elicited over primary somatosensory cortex contralateral to the relevant hand. The amplitude of this component increased with memory load and was sensitive to individual limitations in memory capacity, suggesting that the tCDA reflects the maintenance of tactile information in somatosensory working memory. The tCDA was preceded by a transient negativity (N2cc component) with a similar contralateral scalp distribution, which is likely to reflect selection of task-relevant tactile stimuli at the encoding stage. The temporal sequence of N2cc and tCDA components mirrors previous observations from ERP studies of working memory in vision. The finding that the sustained somatosensory delay period activity varies as a function of memory load supports a sensory recruitment model for spatial working memory in touch.

KEYWORDS:

electroencephalography; event-related potentials; selective attention; somatosensation; working memory

PMID:
25013002
DOI:
10.1093/cercor/bhu153
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center