There is a well-documented bidirectional relationship between pain and
cognitive dysfunction, especially working memory. Despite this extensive body
of research, the pain–working memory relationship is poorly understood. Pain
catastrophizing – exaggerated negative cognitive and emotional responses
towards pain – may contribute to working memory deficits by occupying finite,
shared cognitive resources, but this has yet to be investigated. The present
study sought to clarify the role of pain catastrophizing (assessed as both a
trait-level disposition and state-level process) in working memory dysfunction.
Healthy undergraduate participants were randomized to an ischemic pain or
control task, during which they completed verbal and non-verbal working memory
tests. They also completed measures of state- and trait-level pain
catastrophizing. Mediation analyses indicated that state-level pain
catastrophizing mediated the relationships of pain group to both verbal and
non-verbal working memory, such that participants in the pain group (vs. the
control group) catastrophized more about their pain, which then resulted in
worse verbal and non-verbal working memory performance. In moderated mediation
analyses, trait-level pain catastrophizing moderated this mediation effect for
both verbal and non-verbal working memory. Those participants in the pain group
who reported greater tendency to catastrophize about pain in general exhibited
greater catastrophizing in-the-moment during the pain task, thereby leading to
worse verbal and non-verbal working memory performance. These results provide
evidence for pain catastrophizing as a putative mechanism and moderating factor
of working memory dysfunction in pain. Future research should replicate these
results in chronic pain samples, investigate other potential mechanisms (e.g.,
sleep), and develop interventions to ameliorate cognitive dysfunction by
targeting pain catastrophizing.