RDK-IAPS paradigm EEG, target vs distractor

It has been suggested that the visual system samples attended information
rhythmically. Does rhythmic sampling also apply to distracting
information? How do attended information and distracting information
compete temporally for neural representations? We recorded
electroencephalography (EEG) from participants who detected instances of
coherent motion in a random dot kinematogram (RDK; the target), overlayed
on different categories (pleasant, neutral, and unpleasant) of affective
images from the International Affective System (IAPS) (the distractor).
The moving dots were flickered at 4.29 Hz whereas the IAPS pictures were
flickered at 6 Hz. The time course of EEG spectral power at 4.29 Hz was
taken to index the temporal dynamics of target processing. The spatial
pattern of the EEG spectral power at 6 Hz was similarly extracted and
subjected to a moving-window MVPA decoding analysis to index the temporal
dynamics of processing pleasant, neutral, or unpleasant distractor
pictures. We found that (1) both target processing and distractor
processing exhibited rhythmicity at ∼1 Hz and (2) the phase difference
between the two rhythmic time courses were related to task performance,
i.e., relative phase closer to π predicted a higher rate of coherent
motion detection whereas relative phase closer to 0 predicted a lower rate
of coherent motion detection. These results suggest that (1) in a
target-distractor scenario, both attended and distracting information were
sampled rhythmically and (2) the more target sampling and distractor
sampling were separated in time within a sampling cycle, the less
distraction effects were observed, both at the neural and the behavioral
level.