title: Anticipation increases tactile stimulus processing in the ipsilateral primary somatosensory cortex.
abstract: Stimulus anticipation improves perception. To account for this improvement, we investigated how stimulus processing is altered by anticipation. In contrast to a large body of previous work, we employed a demanding perceptual task and investigated sensory responses that occur beyond early evoked activity in contralateral primary sensory areas: Stimulus-induced modulations of neural oscillations. For this, we recorded magnetoencephalography in 19 humans while they performed a cued tactile identification task involving the identification of either a proximal or a distal stimulation on the fingertips. We varied the cue-target interval between 0 and 1000 ms such that tactile targets occurred at various degrees of anticipation. This allowed us to investigate the influence of anticipation on stimulus processing in a parametric fashion. We observed that anticipation increases the stimulus-induced response (suppression of beta-band oscillations) originating from the ipsilateral primary somatosensory cortex. This occurs in the period in which the tactile memory trace is analyzed and is correlated with the anticipation-induced improvement in tactile perception. We propose that this ipsilateral response indicates distributed processing across bilateral primary sensory cortices, of which the extent increases with anticipation. This constitutes a new and potentially important mechanism contributing to perception and its improvement following anticipation.
authors: Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
authors: Freek
authors: F
authors: van Ede
authors: Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
authors: Floris P
authors: FP
authors: de Lange
authors: Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands.
authors: Eric
authors: E
authors: Maris
mesh_terms: D000328:Adult; D059031:Anticipation, Psychological / Q000502:physiology*; D001611:Beta Rhythm; D003463:Cues; D005260:Female; D005385:Fingers; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D010812:Physical Stimulation; D013003:Somatosensory Cortex / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*
keywords: attentional orienting; distributed sensory processing; magnetoencephalography; sensorimotor beta-oscillations; sensory memory maintenance; spatial attention