Repetition learning of vibrotactile temporal sequences: An fMRI study in blind and sighted individuals

The present fMRI study examined cortical activity to repeated vibrotactile sequences in 11 early blind and 11 sighted participants. All participants performed with > 90% accuracy and showed practice induced improvement with faster reaction times in identifying matched and unmatched vibrotactile sequences. In blind only, occipital/temporal and parietal/somatosensory cortices showed practice induced reductions in positive BOLD amplitudes that possibly reflected repetition induced learning effects. The significant findings in occipital cortex of the blind indicated that perceptual processing of tactile inputs in visually deprived cortex is dynamic as response amplitudes changed with practice. Thus, stimulus processing became more efficient. It was hypothesized that the changes in occipital cortex of the blind reflected life-long skill in processing somatosensory inputs. Both groups showed activity reductions with practice in mid/posterior ventrolateral prefrontal cortex. These activity reductions suggested common stimulus–response learning associations for vibrotactile sequences in mid/posterior ventrolateral prefrontal cortex.

► An fMRI study in early blind and sighted to encoding vibrotactile sequences.
► Repeated practice trials enhanced learning to distinguish matched and unmatched sequences.
► Occipital cortex regions showed repetition induced response reductions only in early blind.
► Somatosensory cortex showed no significant repetition reduction effects in either group.
► Response suppression occurred in prefrontal cortex affected by stimulus–response associations in repetition priming tasks.