The impact of pain on memory: a study in chronic low back pain and migraine patients

Patients with chronic pain often complain of cognitive difficulties, such as 'poor memory'. Both acute and chronic pain are thought to impair cognitive performance by demanding attentional and cognitive resources to the detriment of cognitive functioning. However, systematic experimental investigations in patients, as well as deeper understanding of factors that modulate these effects remain lacking. This study investigated whether patients with chronic migraine or patients with chronic low back pain are more susceptible to the disruptive effects of pain on memory as compared to pain-free healthy controls. Two groups of individuals with chronic pain (<i>n</i> = 55 patients with chronic migraine, <i>n</i> = 59 patients with chronic back pain) and <i>n</i> = 59 age-matched healthy controls, underwent experimental pain stimulation at either the back or head while performing a visual categorization and a subsequent recognition task. Pain-related cognitions and clinical parameters were assessed to explore their influence on pain-cognition interference. This large-scale experimental study revealed encouraging results regarding the impact of experimental pain on memory for the pain disorders studied here. Contrary to our hypothesis, patients with chronic migraine or chronic back pain showed no greater effects of experimental pain on recognition memory than healthy participants. Furthermore, the study showed no effect of stimulation site (i.e. head or lower back) or interaction with type of chronic pain. Pain-related cognitions, psychological variables and clinical parameters only had a marginal effect on pain-induced impairment of recognition memory in pain patients. Future research should focus on identifying cognitive and neural predictors associated with susceptibility or resilience to the disruptive effects of pain. Furthermore, larger and more diverse samples could enable person-centred methods to investigate how cognitive, clinical, and situational factors interact in shaping cognitive performance under pain. Such insights are crucial for the development of targeted, individualized therapeutic approaches in the management of chronic pain syndromes.