Multiple spatial reference frames underpin perceptual recalibration to audio-visual discrepancies.

Area of Science:

• Neuroscience
• Perception
• Auditory processing

Background:

• The perceptual system integrates multisensory information, recalibrating when discrepancies arise.
• The ventriloquism aftereffect (VAE) demonstrates auditory space recalibration due to visual-auditory spatial disparities.
• Previous studies suggest multiple timescales underlie VAE, but reference frame usage remains unclear.

Purpose of the Study:

• To investigate whether the ventriloquism aftereffect (VAE) operates in eye- or head-centered reference frames.
• To examine if spatial reference frame usage in VAE varies across different adaptation durations (seconds to minutes).

Main Methods:

• Developed a novel experimental paradigm to selectively manipulate visual signals in eye- versus head-centered frames.
• Presented auditory stimuli relative to head orientation or fixation point to isolate reference frame contributions.
• Assessed VAE recalibration across a range of adaptation timescales.

Main Results:

• Both eye- and head-centered reference frames were found to contribute to the VAE across all tested timescales.
• No significant interaction was observed between the spatial reference frames used and the duration of adaptation.
• The findings indicate that multiple spatial reference frames are consistently employed in VAE recalibration.

Conclusions:

• The ventriloquism aftereffect (VAE) relies on multiple spatial reference frames, including both eye- and head-centered ones.
• These reference frames are leveraged similarly by the time-sensitive mechanisms underlying VAE, irrespective of adaptation duration.
• This suggests a robust and consistent spatial processing strategy in multisensory integration during VAE.