Neuropsychologic and neuropsychiatric characteristics of patients with Friedreich's ataxia

Abstract

OBJECTIVES AND MATERIALS AND METHODS: Due to recent evidence of frontal-lobe related dysfunctions in patients with cerebellar atrophy, patients with Friedreich's ataxia were compared to normal subjects controlled for age, gender, and educational level on tests measuring information processing speed, visuospatial organization, selective attention, executive functions, and mood.

Results: Patients with Friedreich's ataxia had slowed information speed, as indicated by lengthened simple visual reaction time and increased color-word interference in the Stroop task. However, the patient group was not impaired in several tests sensitive to neocortical and particularly prefrontal cortex lesions, including an untimed version of block design, verbal fluency, Wisconsin card sorting, Tower of Hanoi, and picture arrangement. Despite serious sensorimotor dysfunctions, the patient group did not differ from controls in terms of mood, as evaluated by the Symptoms Checklist (SCL-90) and the Hamilton depression scale.

Conclusion: These results indicate that the slowed information processing speed of patients with Friedreich's ataxia is not accompanied by major prefrontal cortex and mood disorders.