New Article published in Journal of Neuroscience.

Da Costa SE, Miller LM, van der Zwaag W, Clarke S and Saenz M (2013) Tuning in to Sound: frequency-selective attentional filter in human primary auditory cortex, Journal of Neuroscience 33(5): 1858-1863. Featured in This Week in the Journal

Abstract:
Cocktail parties, busy streets, and other noisy environments pose a difficult challenge to the auditory system: how to focus attention on selected sounds while ignoring others? Neurons of primary auditory cortex, many of which are sharply tuned to sound frequency, could help solve this problem by filtering selected sound information based on frequency-content. To investigate whether this occurs, we used high-resolution fMRI at 7 Tesla to map the fine-scale frequency-tuning (1.5 mm isotropic resolution) of primary auditory areas A1 and R in six human participants. Then in a selective attention experiment, participants heard low (250 Hz) and high (4000 Hz) frequency streams of tones presented at the same time (dual-stream) and were instructed to focus attention onto one stream vs. the other, switching back and forth every 30s. Attention to low frequency tones enhanced neural responses within low frequency-tuned voxels relative to high, and when attention switched the pattern quickly reversed. Thus, like a radio, human primary auditory cortex is able to tune into attended frequency channels and can switch channels on demand.