Spontaneous alpha-band oscillations reflect individual differences in audiovisual temporal perception

Area of Science:

• Neuroscience
• Psychophysics
• Cognitive Science

Background:

• Subjective temporal perception, or the point of subjective simultaneity (PSS), shows individual variability.
• Previous research linked spontaneous alpha power to PSS in temporal order judgment (TOJ) tasks.
• Neural mechanisms of individual audiovisual PSS differences in simultaneity judgment (SJ) tasks remain unclear.

Purpose of the Study:

• To investigate the hypothesis that spontaneous alpha band power reflects individual subjective temporal bias.
• To explore the neural mechanisms underlying individual differences in audiovisual PSS within the SJ task.

Main Methods:

• An electroencephalography (EEG) experiment using a simultaneity judgment (SJ) task.
• Subjects judged the synchrony of beep-flash stimuli.
• Correlated alpha-band power differences (visual-leading vs. auditory-leading conditions) with individual PSS.

Main Results:

• A significant positive correlation was found between alpha power difference (V50A - A50V) and individual PSS.
• Higher alpha power differences predicted larger individual PSS.
• Alpha band power differences were found to be significant in the SJ task.

Conclusions:

• Spontaneous alpha power is associated with subjective temporal bias in audiovisual perception.
• Alpha power may reflect spontaneous attentional states influencing PSS.
• Individual differences in alpha power extend to the SJ task, highlighting its role in subjective timing.