Phased mirror tracing outcomes correlate with several hemisphericity measures

Recently, subjects, separated into two large groups by the Dichotic Deafness Test (DDT), a new brain laterality measure. These were significantly correlated with groups separated by two preference-based hemisphericity-type questionnaires, the Preference Questionnaire (PrefQ) and Polarity Questionnaire (PolQ). Here, Mirror-Tracing, another potential biophysical measure of hemisphericity earlier reported to be weakly correlated with laterality, was tested using 171 subjects, the DDT, and both questionnaires. No correlations between the DDT, PrefQ, and PolQ separation methods and Mirror Tracing outcomes were found until individuals identified as having left brain affect were removed from the population. Then, robust correlations appeared for the remaining right-affect subjects alone (n=82). These correlations became even higher when the left brain affect subjects that had been removed (n=89) were "phase corrected" from a contralateral to an ipsilateral connectivity for motor dominance and then returned to the sample (n=171). These Phased Mirror-Tracing (PMT) outcomes were also significantly correlated with 10 of the 11 statements of the PolQ. Thus, PMT joins the DDT as a second performance-based measure of laterality whose outcomes significantly correlated with those of preference-based hemisphericity questionnaires.