Poster F122, Tuesday, March 28, 8:00 – 10:00 am, Pacific Concourse
Differences in Neural Correlates of Error Correction in Auditory and Visual Sensorimotor Synchronization
Daniel Comstock1, Ramesh Balasubramaniam1; 1University of California - Merced
Tapping in synchrony to a metronome with occasional temporal perturbations produces quickly corrected synchronization errors. Previous research has shown that these error corrections fall into two types: period corrections or phase corrections. Period corrections are quick corrections occurring when a perturbation is large enough to be consciously noticed, while phase corrections are more gradual and correspond to perturbations small enough to be subconscious. This study used these temporal perturbations to investigate the differences in the auditory and visual timing mechanisms. Electroencephalography (EEG) was measured during synchronization tapping tasks with either an auditory, or flashing visual metronome, both with an interonset interval of 600 milliseconds. Occasional perturbations of +/- 66 milliseconds and +/- 16 milliseconds were inserted to produce period correction and phase correction responses, respectively. We hypothesized that the corrections in the visual modality would be more gradual than in the auditory modality, and that these differences would be represented by separate neural components as measured by EEG. Our findings show period corrections only in the auditory modality for the +/- 66 perturbations. All other conditions, auditory and visual, produced only phase corrections. EEG data showed an Error Related Negativity (ERN) in the +66 auditory condition as expected, but no ERN was found for any of the visual conditions. Interestingly, Visual P1 and P2 components suggest detection of the +/-66 perturbations, even though they did not translate into a period correction response. The findings suggest the auditory system may have privileged access to timing mechanisms in the brain.
Topic Area: PERCEPTION & ACTION: Multisensory