Cortical potentials at the frequency of absolute wrist velocity become phase-locked during slow sinusoidal tracking movements

Padraig E. O'Suilleabhain, Terrence D. Lagerlund, Joseph Y. Matsumoto

Research output: Contribution to journalArticle

8 Scopus citations


A 1-Hz rhythmic event-related potential was recorded at the scalp during performance of a 0.5-Hz tracking task. At cortical motor areas, negative peaks occurred 10-20 ms after peak tracking speeds. Analysis of single sweeps suggested that EEG phase was reset at initiation of the tracking motion and then maintained a constant relationship to wrist speed until task completion. Frequency analysis indicated that rhythm appearance in the averaged potential was predominantly due to phase-locking, because there was no tracking-related increase in 1 Hz amplitude within individual sweeps. While tracking, phase-locking was present over bilateral parieto-occipital and frontal regions, with a slight predominance at the contralateral frontal region. When subjects observed the target motion, phase-locking was localized to parieto-occipital regions. We suggest mental processes such as visual processing, visuomotor coordination and real-time motor planning are reflected in the pacing of localized cortical potential fluctuations.

Original languageEnglish (US)
Pages (from-to)529-535
Number of pages7
JournalExperimental Brain Research
Issue number4
StatePublished - Jun 30 1999



  • Phase-locking
  • Slow EEG oscillations
  • Topography
  • Tracking

ASJC Scopus subject areas

  • Neuroscience(all)

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