The neural substrate for working memory of tactile surface texture

Authors

  • Amanda L. Kaas,

    Corresponding author
    1. Department of Cognitive Neuroscience, Faculty of Psychology, Maastricht University, The Netherlands
    • Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Postbus 616, Maastricht 6200MD, The Netherlands
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  • Hanneke van Mier,

    1. Department of Cognitive Neuroscience, Faculty of Psychology, Maastricht University, The Netherlands
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  • Maya Visser,

    1. Department of Cognitive Neuroscience, Faculty of Psychology, Maastricht University, The Netherlands
    2. Universitat Pompeu Fabra, Dept. de Tecnologies de la Informació i les Comunicacions, Barcelona, Spain
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  • Rainer Goebel

    1. Department of Cognitive Neuroscience, Faculty of Psychology, Maastricht University, The Netherlands
    2. F.C. Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Radboud University Nijmegen, The Netherlands
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Abstract

Fine surface texture is best discriminated by touch, in contrast to macro geometric features like shape. We used functional magnetic resonance imaging and a delayed match-to-sample task to investigate the neural substrate for working memory of tactile surface texture. Blindfolded right-handed males encoded the texture or location of up to four sandpaper stimuli using the dominant or non-dominant hand. They maintained the information for 10–12 s and then answered whether a probe stimulus matched the memory array. Analyses of variance with the factors Hand, Task, and Load were performed on the estimated percent signal change for the encoding and delay phase. During encoding, contralateral effects of Hand were found in sensorimotor regions, whereas Load effects were observed in bilateral postcentral sulcus (BA2), secondary somatosensory cortex (S2), pre-SMA, dorsolateral prefrontal cortex (dlPFC), and superior parietal lobule (SPL). During encoding and delay, Task effects (texture > location) were found in central sulcus, S2, pre-SMA, dlPFC, and SPL. The Task and Load effects found in hand- and modality-specific regions BA2 and S2 indicate involvement of these regions in the tactile encoding and maintenance of fine surface textures. Similar effects in hand- and modality-unspecific areas dlPFC, pre-SMA and SPL suggest that these regions contribute to the cognitive monitoring required to encode and maintain multiple items. Our findings stress both the particular importance of S2 for the encoding and maintenance of tactile surface texture, as well as the supramodal nature of parieto-frontal networks involved in cognitive control. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.

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