Lexical Memory Deficit in Fibromyalgia Syndrome

Abstract

Objective

Word naming speed is slow in fibromyalgia syndrome [FMS] patients, suggesting a lexical processing disadvantage. This study examines whether a comparable disadvantage exists for verbal fluency, a skill that depends on the activation of appropriate lexical processes. Specifically, we predicted that slow naming speed will be closely related to reductions in verbal fluency in FMS.

Methods

One hundred and four patients with FMS and a history of memory complaints were divided into two groups according to performance on a naming speed measure. Group 1 consisted of 46 patients who performed at or below the 10th percentile on naming speed. Group 2 contained 58 patients who performed above the 10th percentile. The two groups completed the phonemic verbal fluency subscale of the Controlled Oral Word Association Test.

Results

There was a statistically significant difference between the two groups in word generation. The slow naming speed group generated 8.3 fewer words on a time-constrained task. They generated on average three fewer words to each of the cueing letters F, A, and S in a 60-second time period.

Conclusions

Abnormalities in naming speed and phonemic verbal fluency are prominent clinical features of FMS and appear closely linked. Inferences derived from these abnormalities have the potential to transform our picture of how cognition in FMS dysfunctions. Deficits in lexical memory may signal a core area of cognitive deficiency in FMS.

Keywords:

• Fibromyalgia syndrome
• naming speed
• phonemic verbal fluency
• lexical memory
• episodic memory

ACKNOWLEDGEMENTS

Declaration of interest: The authors report no conflict of interest.