Working Memory Impairment in Fibromyalgia Patients Associated with Altered Frontoparietal Memory Network

Abstract

BackgroundFibromyalgia (FM) is a disorder characterized by chronic widespread pain and frequently associated with other symptoms. Patients with FM commonly report cognitive complaints, including memory problem. The objective of this study was to investigate the differences in neural correlates of working memory between FM patients and healthy subjects, using functional magnetic resonance imaging (MRI).Methodology/Principal FindingsNineteen FM patients and 22 healthy subjects performed an n-back memory task during MRI scan. Functional MRI data were analyzed using within- and between-group analysis. Both activated and deactivated brain regions during n-back task were evaluated. In addition, to investigate the possible effect of depression and anxiety, group analysis was also performed with depression and anxiety level in terms of Beck depression inventory (BDI) and Beck anxiety inventory (BAI) as a covariate. Between-group analyses, after controlling for depression and anxiety level, revealed that within the working memory network, inferior parietal cortex was strongly associated with the mild (r = 0.309, P = 0.049) and moderate (r = 0.331, P = 0.034) pain ratings. In addition, between-group comparison revealed that within the working memory network, the left DLPFC, right VLPFC, and right inferior parietal cortex were associated with the rating of depression and anxiety?Conclusions/SignificanceOur results suggest that the working memory deficit found in FM patients may be attributable to differences in neural activation of the frontoparietal memory network and may result from both pain itself and depression and anxiety associated with pain.

Are Fibromyalgia Patients Cognitively Impaired? Objective and Subjective Neuropsychological Evidence

“…Consistent with previous studies showing a slowdown in the response processing of FM patients (36), our patients were slower in selecting whether the target was similar to or different than a previous stimulus. Seo and colleagues also observed that when a greater amount of manipulation (e.g., 2-Back condition) was required, FM patients also showed reduced accuracy (36). It is therefore possible that our task was sensitive enough to detect differences in reaction times but not difficult enough to require a great amount of manipulation (37) to bring out differences in accuracy.…”

Fibromyalgia: A Critical and Comprehensive Review

“…It should be pointed out that there are also numerous tests on which FMS patients perform similar to healthy subjects, and that the results for the same tests may not always agree between different investigations [186,191,192,195,196]. In addition, the comparison of FMS patients to healthy subjects may reveal relatively subtle deficits, even though the patients perform within the normal range compared to normative data.…”

“…As a matter of fact, there are indications that cognitive deficits in FMS patients become most obvious in the presence of a distractor or source of stimulus competition, not only in tests of attention but also in tests of working memory [193,194]. Working memory is another cognitive domain where FMS patients very consistently perform more poorly compared to healthy controls [186,187,192,195,196]. While addressed in fewer studies, certain measures of semantic memory also show impairments in FMS, including decreased verbal fluency, naming speed, and vocabulary [187,195,197].…”

“…Other methodological differences and patient heterogeneity are also likely to contribute to the observed inconsistencies. The lack of association between depression and memory function is somewhat surprising since the dorsolateral prefrontal cortex (DLPFC) is strongly implicated in protecting from depression [210] and activation of the DLPFC is a typical finding during working memory performance in healthy controls as well as patients with FMS [196,211]. However, the degree of activation was lower in FMS patients compared to healthy controls, and this difference was largely accounted for by the depressive symptom scores [196].…”

Fibromiyaljide Kognitif Disfonksiyon

“…FMS'da kısa süreli hafıza bozukluğu MRI'de nöral bağlantı değişiklikleri ile açıklanmaktadır. Buna göre FMS hastalarında frontotemporal hafıza ağındaki nöral aktivasyon değişiklikleri hem ağrı hem de ağrı ile ilişkili depresyon ve anksiyete'den sorumlu olabilir 26 . FMS'lu hastalarda genel kognitif fonksiyonlarda bozulmaya dair pek çok delil vardır.…”