Identification of lexical-phonological networks in the superior temporal sulcus using functional magnetic resonance imaging.

General agreement exists that dorsal aspects of the temporal lobe support the perception of speech but there is less agreement regarding the mapping between levels of speech processing and neural regions within the dorsal temporal lobe. The present experiment sought to identify temporal lobe regions that support one such level, namely, lexical-phonological representation/processing. To do this, we manipulated phonological neighborhood density, a variable that affects processing within lexical-phonological networks. In a functional magnetic resonance imaging experiment, 10 participants listened to blocks of either high-density or low-density words. High-density words produced significantly more activation in the posterior half of the superior temporal sulcus bilaterally, suggesting that these regions are involved in lexical-phonological processing networks.