BIROn - Birkbeck Institutional Research Online

    Independent attention mechanisms control the activation of tactile and visual working memory representations

    Katus, Tobias and Eimer, Martin (2018) Independent attention mechanisms control the activation of tactile and visual working memory representations. Journal of Cognitive Neuroscience , ISSN 0898-929X. (In Press)

    [img]
    Preview
    Text
    capac_JOCN_FINAL.pdf - Author's Accepted Manuscript

    Download (873kB) | Preview

    Abstract

    Working memory (WM) is limited in capacity, but it is controversial whether these capacity limitations are domain-general or are generated independently within separate modality-specific memory systems. These alternative accounts were tested in bimodal visual/tactile WM tasks. In Experiment 1, participants memorized the locations of simultaneously presented task-relevant visual and tactile stimuli. Visual and tactile WM load was manipulated independently (1, 2 or 3 items per modality), and one modality was unpredictably tested after each trial. To track the activation of visual and tactile WM representations during the retention interval, the visual and tactile contralateral delay activity (CDA and tCDA) were measured over visual and somatosensory cortex, respectively. CDA and tCDA amplitudes were selectively affected by WM load in the corresponding (tactile or visual) modality. The CDA parametrically increased when visual load increased from 1 to 2 and to 3 items. The tCDA was enhanced when tactile load increased from 1 to 2 items, and showed no further enhancement for 3 tactile items. Critically, these load effects were strictly modality-specific, as substantiated by Bayesian statistics. Increasing tactile load did not affect the visual CDA, and increasing visual load did not modulate the tCDA. Task performance at memory test was also unaffected by WM load in the other (untested) modality. This was confirmed in a second behavioral experiment where tactile and visual loads were either two or four items, unimodal baseline conditions were included, and participants performed a color change detection task in the visual modality. These results show that WM capacity is not limited by a domain-general mechanism that operates across sensory modalities. They suggest instead that WM storage is mediated by distributed modality-specific control mechanisms that are activated independently and in parallel during multisensory WM.

    Metadata

    Item Type: Article
    School: School of Science > Psychological Sciences
    Depositing User: Martin Eimer
    Date Deposited: 28 Feb 2018 11:19
    Last Modified: 11 Feb 2021 22:44
    URI: https://eprints.bbk.ac.uk/id/eprint/21428

    Statistics

    Downloads
    Activity Overview
    442Downloads
    133Hits

    Additional statistics are available via IRStats2.

    Archive Staff Only (login required)

    Edit/View Item Edit/View Item