The Gender Specific Influence of Acoustic Noise on Auditory and Language Cortical Activation Patterns of the Dominant Hemisphere The Gender Specific Influence of Acoustic Noise on Auditory and Language Cortical Activation Patterns of the Dominant Hemisphere

Purpose and Background: Inter-gender cortical and functional asymmetry is an ongoing topic of investigation. In the current study, we investigated auditory and language cortical activation patterns in the dominant hemisphere to text listening under changing levels of background acoustic scanner noise in normal hearing male and female subjects. Materials & Methods: Echo-planar functional MRI (1.5T) was performed on 12 healthy right-handed subjects (6 males, 6 females). Passive text listening tasks were employed under two different background acoustic scanner noise conditions (12 slices/2 sec TR (6Hz) and 4 slices/2 sec TR (2Hz)), with the first 4 slices in identical locations in the left hemisphere. Cross correlation analysis was used to construct activation maps in subregions of auditory and language relevant cortex of the dominant (left) hemisphere, and activation areas were calculated using coefficient thresholds of 0.5, 0.6, and 0.7. Results: Text listening caused robust activation in anatomically defined auditory cortex, and weaker activation in language relevant cortex of all 12 individuals. As a whole, there was no significant difference in regional cortical activation between the two background acoustic scanner noise conditions. When gender was considered, male compared to female subjects showed a significantly (p <0.01) greater change in left hemisphere activation during the high scanner noise rate condition. This effect was significant (p<0.05) in the left superior temporal gyrus, the posterior aspect of the left middle temporal gyrus and superior temporal sulcus, and the left inferior frontal gyrus.