Individual differences in cognitive performance under pain linked to region-specific alpha power modulations

Chronic pain is associated with reduced cognitive function, potentially due to a diversion of cognitive resources to processing pain. However, reduced cognitive function during pain is not always consistently evidenced, perhaps due to individual differences in the attentional cost of pain processing. In the current electroencephalography investigation, we therefore examined differences in the top-down modulation of oscillatory activity in a cognitive task, between participants who performed better, and worse, during experimentally induced neuropathic-like pain. We employed a cross-modal attention task in which visual cues indicated whether participants needed to judge the visual orientation or discriminate the auditory pitch of an upcoming target. The visual and auditory targets were presented either simultaneously or individually, enabling us to assess the "cost" of having a distractor present in each modality. Participants engaged in the task under two conditions: prolonged pain via the capsaicin-heat pain model, and pain-free. Participants less "costed" by visual distraction during pain demonstrated a greater increase in alpha power (8-12 Hz) over frontal/central electrodes during pain. This may reflect inhibition of regions related to the processing of painful stimuli (somatosensory cortex), which could increase availability of resources to meet task-demands - a possible task-favouring pattern. In conclusion, our results support the notion that better cognitive function during pain is associated with a behavioral strategy.