Neuro-cognitive foundations of word stress processing - evidence from fMRI.

BACKGROUND: To date, the neural correlates of phonological word stress processing are largely unknown. METHODS: In the present study, we investigated the processing of word stress and vowel quality using an identity matching task with pseudowords. RESULTS: In line with previous studies, a bilateral fronto-temporal network comprising the superior temporal gyri extending into the sulci as well as the inferior frontal gyri was observed for word stress processing. Moreover, we found differences in the superior temporal gyrus and the superior temporal sulcus, bilaterally, for the processing of different stress patterns. For vowel quality processing, our data reveal a substantial contribution of the left intraparietal cortex. All activations were modulated by task demands, yielding different patterns for same and different pairs of stimuli. CONCLUSIONS: Our results suggest that the left superior temporal gyrus represents a basic system underlying stress processing to which additional structures including the homologous cortex site are recruited with increasing difficulty.