The interference of experimental pain and cognition in patients suffering from chronic pain
Personality Psychology, Clinical and Medical Psychology, Methodology
Final Report Abstract
This project investigated the effects of experimental pain stimuli on cognitive functioning, in particular on episodic memory. The study aim was to examine whether patients with chronic pain, who often report cognitive impairments in everyday life - particularly memory problems - exhibit stronger pain-induced reductions in performance in a memory task. Furthermore, it was planned to use brain imaging (magnetic resonance imaging) to identify possible neuronal biomarkers that are associated with an increased or decreased susceptibility to the negative effects of pain on cognitive functions. Three groups were examined: n = 60 patients with chronic back pain, n = 60 patients with chronic migraine and n = 60 healthy study participants. In summary, the study results revealed that all three groups showed comparable effects of experimental pain on the memorization (encoding) of neutral images. In all groups, the simultaneous application of electrical stimuli to the presentation of images led to lower recognition performance for these images, regardless of the location of pain stimulation (lower back and forehead) and the individual level of pain-related cognitions and clinical parameters (e.g., pain intensity). Although the patients showed higher values in variables such as painrelated anxiety, catastrophizing and depression, both the pain-related reductions in memory performance and neuropsychological functions were comparable to those of the healthy control group. Neuropsychological examinations showed that the slight cognitive impairments detected in the patient groups could be explained by age and pain-associated comorbidities (e.g. sleep disorders). Only the executive functions showed slight reductions in performance in both patient groups, even after controlling for potentially relevant variables (“covariates”). Overall, these results indicate largely intact neurocognitive abilities, which are neither influenced by the pain disorder itself nor enhanced by experimental pain stimuli.
