The effect of pain on cognitive function: A review of clinical and preclinical research

Abstract

Cognitive impairment is commonly associated with the pain experience. This impairment represents a major obstacle to daily activities and rehabilitation, especially in the chronic pain population. Here we review clinical and preclinical studies that have investigated pain-related alterations in cognition. These include impaired attentional, executive and general cognitive functioning. We describe the anatomical, neurochemical and molecular substrates common to both cognitive processing and supraspinal pain processing, and present the evidence for their involvement in pain-related cognitive impairment. We also examine the added complexity of cognitive impairment caused by analgesic medications and how this can further impact on morbidity in chronic pain patients. The need for a better understanding of the mechanisms of both pain-induced and treatment-related cognitive impairment is highlighted. Further research in this area will aid our understanding of patient symptoms and their underlying pathophysiology, ultimately leading to increased provision of guided therapy.

Associations between cognitive performance and pain in chronic fatigue syndrome: comorbidity with fibromyalgia does matter

“…Because age (14), fatigue severity (42), and depressive symptoms (43) may significantly influence cognitive function as well as pain measurements, the analyses were also performed with these variables separately entered as additional predictor variables (covariates).…”

“…Accordingly, we recently demonstrated that performance-based cognitive capabilities are significantly worse both in CFS patients with and without FM compared with healthy controls (13). Indeed, an overlap exists in components of the pain neuromatrix and brain regions involved in cognitive processing (e.g., anterior cingulate cortex, insular cortex, periaqueductal gray) (14). Together with the demonstrated changes in neuroplasticity [e.g., gray matter volume reduction (15)(16)(17)] and dysregultated neurochemistry [e.g., decreased levels of brain-derived neurotrophic factor (18), increased levels of gamma-aminobutric acid (19), increased levels of pro-inflammatory cytokines (20)], these pain-induced changes in resource utilization may (in part) explain (pain-related) cognitive impairment in chronic pain patients.…”

The predictive value of attentional bias towards pain-related information in chronic pain patients: A diary study

“…Third, a chronic pain population is 22 known to generally respond slower than pain-free participants. Indeed, general deficits in information processing have been frequently reported in patients with chronic pain [20,34]. This may have resulted in more noise in the reaction time data compared to studies in healthy volunteers.…”

Comparison of the cognitive performance of elderly caregivers with and without chronic pain

“…It can trigger negative interference in daily activities and in the quality of life of the individuals, in addition to influencing cognitive aspects (7) . Pain is a stimulus capable of affecting the dynamic state of the encephalon, since the neural systems involved in cognition are also closely linked to modulation and perception systems of pain (7)(8) . This interaction between neural structures impairs the speed with which information reaches the brain and the processing capacity of this information, predisposing patients with chronic pain to cognitive deficit (7)(8) .…”

“…From the results, the authors considered that there are strong signs that pain harms/affects cognitive domains, evidencing the superposition of neuroanatomic and neurochemical substrates involved in pain and cognition (8) .…”