Perceptually relevant remapping of human somatotopy in 24 hours
Abstract
Experience-dependent reorganisation of functional maps in the cerebral cortex is well described in the primary sensory cortices. However, there is relatively little evidence for such cortical reorganisation over the short-term. Using human somatosensory cortex as a model, we investigated the effects of a 24-hour gluing manipulation in which the right index and right middle fingers (digits 2 & 3) were adjoined with surgical glue. Somatotopic representations, assessed with two 7 tesla fMRI protocols, revealed rapid off-target reorganisation in the non-manipulated fingers following gluing, with the representation of the ring finger (digit 4) shifted towards the little finger (digit 5) and away from the middle finger (digit 3). These shifts were also evident in two behavioural tasks conducted in an independent cohort, showing reduced sensitivity for discriminating the temporal order of stimuli to the ring and little fingers, and increased substitution errors across this pair on a speeded reaction time task.
Article and author information
Author details
Funding
University College, Oxford
- James Kolasinski
Wellcome (104128/Z/14/Z)
- Tamar R Makin
Wellcome (102584/Z/13/Z)
- Charlotte J Stagg
Medical Research Council (MR/L009013/1)
- Saad Jbabdi
Wellcome (110027/Z/15/Z)
- Heidi Johansen-Berg
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All data were acquired in accordance with local central university research ethics committee approval (University of Oxford MSD-IDREC-C2-2013-05). Eighteen participants were recruited, each providing written informed consent to take part in this study, and for the results of this study to be published.
Copyright
© 2016, Kolasinski et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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