Cognitive deficits in post-stroke aphasia

The assessment of aphasics' cognitive performance is challenging and such patients are generally excluded from studies that describe cognitive deficits after stroke. We evaluated aphasics' performance in cognitive tasks compared to non-aphasic subjects. A sample of 47 patients (21 aphasics, 17 non-aphasics with left hemisphere lesions and 9 non-aphasics with right hemisphere lesions) performed cognitive tasks (attention, verbal and visual memory, executive functions, visuospatial skills and praxis). Aphasic patients performed poorer than all non-aphasics in Digit Span (p < 0.001), Clock-Drawing Test (p = 0.006), Verbal memory (p = 0.002), Visual Memory (p < 0.01), Verbal Fluency (p < 0.001), and Gesture Praxis (p < 0.001). Aphasia severity correlated with performance in Trail Making test part B (p = 0.004), Digit Span forward (p < 0.001) and backwards (p = 0.011), and Gesture Praxis (p = 0.002). Aphasia is accompanied by deficits not always easy to be evaluated by cognitive tests due to speech production and motor impairments. Assessment of cognitive functions in aphasics might contribute to optimize therapeutic intervention.