Age-related behavioural and neurofunctional patterns of second language word learning: different ways of being successful.

This study aimed at investigating the neural basis of word learning as a function of age and word type. Ten young and ten elderly French-speaking participants were trained by means of a computerized Spanish word program. Both age groups reached a similar naming accuracy, but the elderly required significantly more time. Despite equivalent performance, distinct neural networks characterized the ceiling. While the young cohort showed subcortical activations, the elderly recruited the left inferior frontal gyrus, the left lingual gyrus and the precuneus. The learning trajectory of the elderly, the neuroimaging findings together with their performance on the Stroop suggest that the young adults relied on control processing areas whereas the elderly relied on episodic memory circuits, which may reflect resorting to better preserved cognitive resources. Finally, the recruitment of visual processing areas by the elderly may reflect the impact of the language training method used.