SEX DIFFERENCES IN SELECTIVE AUDITORY ATTENTION DURING DICHOTIC LISTENING WITH DIFFERENT LEVELS OF COMPLEXITY: AN FMRI STUDY

A group of 20 healthy subjects (11 males and 9 females) performed a selective auditory attention task in a dichotic listening paradigm with different levels of perceptual load. Analysis of brain activation patterns measured with fMRI during selective listening to fusion speech with distractors of varying strengths revealed statistically significant sex differences in the topography of cortical activity. "Female > male" effects dominated in the left superior temporal gyrus and the left pre and post-central gyrus; while the most pronounced "male > female" effects were found in the left islet, shell and frontal lobule. Statistically significant effects were also obtained by comparing activation patterns according to the level of task complexity: It was shown that masking with a female speaker's voice caused greater activation of additional high-level information processing areas. The findings indicate the presence of sexual dimorphism in the organization of the selective auditory attention system.