The relationships between cognitive control and psychological symptoms in patients with somatic symptom disorder: a pilot longitudinal study.

Introduction: The present study explored how neurocognitive function correlated with the clinical symptoms of somatic symptom disorder (SSD) by evaluating changes in cognitive abilities according to differences in relevant factors.

Methods: A total of 44 patients with SSD and 30 healthy controls completed tests assessing various neurocognitive domains, including verbal memory, psychomotor speed, executive function, working memory, and sustained and divided attention. They also completed questionnaires for psychological assessment. The same tests and questionnaires were completed by 26 SSD patients 6 months later.

Results: The SSD patients had significantly lower scores on the attentional and verbal memory tests than did the healthy controls. Performance on the attentional test was significantly associated with the level of somatic symptoms and anxiety. The follow-up assessment results of the SSD patients revealed improved performance on the verbal learning and fluency tests as well as improvements in somatic symptoms, anxiety, and depression. It was also observed that changes in verbal learning and attentional functions were significantly associated with improvements in somatic symptoms.

Conclusions: The present study suggests that neurocognitive dysfunctions are subtle and not specific to SSD, but certain cognitive functions may be related to the clinical symptoms and improvements of patients with SSD.