The role of working memory in the attentional control for pain
Disengaging attention away from a nociceptive stimulus has been shown to effectively reduce pain. However, because pain signals the occurrence of potential tissue damage, nociceptive stimuli are prompt to capture attention despite voluntary control. A recent model stresses that an effective attentional control of pain does not simply imply the disengagement of attention, but depends also on cognitive factors that guarantee that attention is maintained on the processing of pain-unrelated information without being recaptured by nociceptive stimuli. Supporting this view, experiments have shown that the ability of nociceptive stimuli to capture attention can be modulated by top-down factors. In this frame, we have explored the involvement of working memory in the control of the attentional capture by nociception. Working memory is involved in the short-term maintaining and storing of information for its immediate manipulation, and has been suggested to regulate the top-down control of attention by maintaining current processing priorities during task performance. Through a series of psychophysical experiments, we found that engaging subjects in a task involving working memory significantly reduces the distraction induced by nociceptive stimuli. Furthermore, using EEG, we found that engaging working memory reduces the magnitude of early-latency responses to the nociceptive stimulus, indicating an effect already at the earliest stages of nociceptive processing. Taken together, the present results suggest that cognitive strategies involving working memory to shield cognition from nociception could be used to alleviate pain.