Persistent recruitment of somatosensory cortex during active maintenance of hand images in working memory

• Published in: NeuroImage (Orlando, Fla.) Vol. 174; pp. 153 - 163
• Main Authors: Galvez-Pol, A., Calvo-Merino, B., Capilla, A., Forster, B.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2018; Elsevier Limited
• Subjects: Body perception; Brain research; Cortex (somatosensory); Embodiment; Ethics; Hands; Information processing; Memory; Perceptions; Sensory integration; Sensory recruitment; SEPs; Short term memory; Somatosensory cortex; Visual cortex; Visual stimuli; Working memory; Sensory recruitment; Body perception; Somatosensory cortex; SEPs; Working memory; Embodiment
• ISSN: 1053-8119; 1095-9572
• DOI: 10.1016/j.neuroimage.2018.03.024

Working memory (WM) supports temporary maintenance of task-relevant information. This process is associated with persistent activity in the sensory cortex processing the information (e.g., visual stimuli activate visual cortex). However, we argue here that more multifaceted stimuli moderate this sensory-locked activity and recruit distinctive cortices. Specifically, perception of bodies recruits somatosensory cortex (SCx) beyond early visual areas (suggesting embodiment processes). Here we explore persistent activation in processing areas beyond the sensory cortex initially relevant to the modality of the stimuli. Using visual and somatosensory evoked-potentials in a visual WM task, we isolated different levels of visual and somatosensory involvement during encoding of body and non-body-related images. Persistent activity increased in SCx only when maintaining body images in WM, whereas visual/posterior regions' activity increased significantly when maintaining non-body images. Our results bridge WM and embodiment frameworks, supporting a dynamic WM process where the nature of the information summons specific processing resources. •Dissociation of somatosensory-evoked potentials (SEPs) from visual processing of body-related images in WM.•Distinctive modulation of SEPs by memory load only during maintenance of body-related stimuli.•Type of information embedded in the visual stimuli summons specific processing resources (embodiment mechanisms acting upon WM processes).