Training-induced brain remapping in chronic aphasia: a pilot study.

BACKGROUND

The neural correlates of training-induced improvements of cognitive functions after brain damage remain still scarcely understood. In the specific case of aphasia, although several investigations have addressed the issue of the neural substrates of functional recovery, only a few studies have attempted to assess the impact of language training on the damaged brain.

AIMS: The main goal of this study was to examine the neurobiological correlates of improved picture-naming performance in 2 aphasic patients who received intensive and specific training for a chronic and severe phonological anomia.

METHODS

In both participants, picture-naming performance was assessed before and after phonological cueing training. Training-induced changes in patients' performance were correlated to brain activity patterns as revealed by pre- and post-training event-related functional magnetic resonance imaging scanning.

RESULTS

Training-induced improvement was observed concurrently with changes in the brain activation patterns. Better performance was observed in the patient with the smaller lesion, partially sparing Broca's area, who showed a left perilesional reactivation. Conversely, the patient with complete destruction of Broca's area showed a posttraining activation in the right mirror frontal region.

CONCLUSIONS

The results show that, even in the chronic stage, phonological strategies may improve impaired naming and induce cerebral reorganization.