Phased mirror tracing outcomes correlate with several hemisphericity measures

Area of Science:

• Neuroscience
• Cognitive Psychology
• Biophysics

Background:

• Brain laterality and hemisphericity are complex traits.
• Existing measures include preference-based questionnaires (PrefQ, PolQ) and performance-based tests like the Dichotic Deafness Test (DDT).
• Mirror-Tracing has shown weak correlations with laterality previously.

Purpose of the Study:

• To investigate Mirror-Tracing as a potential biophysical measure of hemisphericity.
• To assess correlations between Mirror-Tracing, DDT, PrefQ, and PolQ.
• To explore the impact of 'brain affect' (left vs. right) on these correlations.

Main Methods:

• 171 subjects were tested using Mirror-Tracing, DDT, PrefQ, and PolQ.
• Initial analysis excluded individuals with left brain affect.
• A 'phase correction' method was applied to data from left brain affect subjects before re-inclusion.

Main Results:

• No initial correlations were found between Mirror-Tracing and other measures.
• Robust correlations emerged for right-affect subjects after excluding left-affect individuals.
• Phased Mirror-Tracing (PMT) showed significant correlations with DDT, PrefQ, and PolQ, especially after phase correction.

Conclusions:

• Phased Mirror-Tracing (PMT) is a valid performance-based measure of brain laterality.
• PMT demonstrates significant correlation with preference-based hemisphericity measures.
• The findings suggest that accounting for 'brain affect' and applying phase correction enhances the utility of biophysical laterality measures.