Cognitive functioning and magnetic resonance imaging in chronic fatigue

Area of Science:

• Neuroscience
• Psychiatry
• Internal Medicine

Background:

• Chronic fatigue is a debilitating condition with cognitive impairment.
• The underlying causes of cognitive dysfunction in chronic fatigue are debated.
• Potential causes include depression, anxiety, or direct brain pathology.

Purpose of the Study:

• To investigate if depression and anxiety explain cognitive dysfunction in chronic fatigue.
• To determine if brain pathology, visualized by MRI, is responsible for cognitive deficits.
• To differentiate between psychogenic and organic causes of cognitive impairment in chronic fatigue.

Main Methods:

• Recruited 26 subjects with chronic fatigue (with/without depression) and 18 healthy controls.
• Included 13 psychiatric controls with depression for comparison.
• Administered standardized cognitive tests and performed Magnetic Resonance Imaging (MRI) for cerebral white-matter lesions.

Main Results:

• No significant performance differences were found between chronic fatigue subjects and controls on cognitive tests.
• Subjective cognitive complaints correlated with the severity of psychopathology.
• Cerebral white-matter lesions were infrequent and found across all groups; no significant differences observed.

Conclusions:

• Subjective cognitive impairment is common in chronic fatigue but lacks objective cognitive or MRI evidence.
• Cognitive complaints in chronic fatigue likely stem from psychopathology (depression/anxiety).
• Findings suggest cognitive dysfunction is not due to a post-viral brain pathology.