Vibrotactile stimulus order effects in somatosensory cortical areas of rhesus monkeys

H. Burton, R. J. Sinclair, Ken Whang

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


This study demonstrated effects of stimulus order on single-cell responses in the macaque primary and secondary somatosensory and 7b cortical areas. As part of a study of tactile attention, two monkeys (Macaca mulatta) received similar constant amplitude, sinusoidal tactile vibration patterns (125 Hz) at two glabrous skin, hand locations. The stimuli started asynchronously with offsets of 150 or 300 ms. In cells with bilateral receptive fields and increased firing to a stimulus, we observed an average lowering of 30% in the firing rates to the contralateral stimulus when preceded by stimulation of the ipsilateral hand. Some cells with only contralateral receptive fields showed similar depressed responses to a contralateral stimulus when preceded by an ipsilateral stimulus. Stimulus order effects were more prominent during dual stimulation of the receptive field on one hand. In six cells whose background activity was inhibited by the first stimulus, higher rates appeared at the onset of the second stimulus. These results suggest a possible substrate for psychophysical findings of stimulus masking in which a preceding stimulus depresses detection thresholds. The spatial and temporal characteristics of in-field inhibitory mechanisms best account for the observed stimulus order effects.

Original languageEnglish
Pages (from-to)316-324
Number of pages9
JournalSomatosensory and Motor Research
Issue number4
StatePublished - 1998


  • Hand
  • Mechanoreception
  • Touch


Dive into the research topics of 'Vibrotactile stimulus order effects in somatosensory cortical areas of rhesus monkeys'. Together they form a unique fingerprint.

Cite this