Pre-attentive and attentive processing of static and motion stimuli in the acoustic free field

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The four electrophysiological studies in this thesis explore various aspects of auditory processing. First, they examine the inconsistent hypotheses regarding contralateral and hemispheric dominance in both pre-attentive and attentive spatial processing within the auditory cortex. The findings indicate a strong contralateral dominance in pre-attentive processing of static sound source positions, while attentive processing reveals a crucial role for the right auditory cortex. This discrepancy suggests a specific, predominantly right-lateralized attention mechanism essential for discerning spatial positions. Additionally, the lateralization in processing static versus motion sounds depends on the attended acoustic attribute and the context of the stimuli. Second, the combination of electrophysiological and behavioral data indicates that the central auditory system can integrate spatial separation between sound sources, even when differences are imperceptible at threshold levels. This suggests that pre-attentive discrimination relies on an object-related comparison process using all available location cues. Third, the results support a general contralateral dominance in the cortical processing of acoustic space information, likely linked to the functional dominance of contralateral cortical afferents. Finally, findings for static and motion stimuli provide electrophysiological evidence for distinct cortical processing mechani