Hearing it right: Evidence of hemispheric lateralization in auditory imagery

An advantage of the right ear (REA) in auditory processing (especially for verbal content) has been firmly established in decades of behavioral, electrophysiological and neuroimaging research. The laterality of auditory imagery, however, has received little attention, despite its potential relevance for the understanding of auditory hallucinations and related phenomena. In Experiments 1-4 we find that right-handed participants required to imagine hearing a voice or a sound unilaterally show a strong population bias to localize the self-generated auditory image at their right ear, likely the result of left-hemispheric dominance in auditory processing. In Experiments 5-8 - by means of the same paradigm - it was also ascertained that the right-ear bias for hearing imagined voices depends just on auditory attention mechanisms, as biases due to other factors (i.e., lateralized movements) were controlled. These results, suggesting a central role of the left hemisphere in auditory imagery, demonstrate that brain asymmetries can drive strong lateral biases in mental imagery.