Data from: EEG theta dynamics within frontal and parietal cortices for error processing during reaching movements in a prism adaptation study altering visuo-motor predictive planning

Modulation of frontal midline theta (fmθ) is observed during error
commission, but little is known about the role of theta oscillations in
correcting motor behaviours. We investigate EEG activity of healthy
partipants executing a reaching task under variable degrees of
prism-induced visuo-motor distortion and visual occlusion of the initial
arm trajectory. This task introduces directional errors of different
magnitudes. The discrepancy between predicted and actual movement
directions (i.e. the error), at the time when visual feedback (hand
appearance) became available, elicits a signal that triggers on-line
movement correction. Analysis were performed on 25 EEG channels. For each
participant, the median value of the angular error of all reaching trials
was used to partition the EEG epochs into high- and low-error conditions.
We computed event-related spectral perturbations (ERSP) time-locked either
to visual feedback or to the onset of movement correction. ERSP
time-locked to the onset of visual feedback showed that fmθ increased in
the high- but not in the low-error condition with an approximate time lag
of 200 ms. Moreover, when single epochs were sorted by the degree of motor
error, fmθ started to increase when a certain level of error was exceeded
and, then, scaled with error magnitude. When ERSP were time-locked to the
onset of movement correction, the fmθ increase anticipated this event with
an approximate time lead of 50 ms. During successive trials, an error
reduction was observed which was associated with indices of adaptations
(i.e., aftereffects) suggesting the need to explore if theta oscillations
may facilitate learning. To our knowledge this is the first study where
the EEG signal recorded during reaching movements was time-locked to the
onset of the error visual feedback. This allowed us to conclude that theta
oscillations putatively generated by anterior cingulate cortex activation
are implicated in error processing in semi-naturalistic motor behaviours.