E-ISSN : 2733-4538
A study was conducted to examine the distribution of intermanual differences on 5 performance tests commonly used in neuropsychological assessment and to investigate the validity of the "10%" criterion in Koreans. The subjects were 141 right-handed college students. They were evaluated on 1-hour test battery that included the Edinburgh Handedness Inventory, the Dot-filling Test, the Finger Tapping Test, the Purdue Pegboard Test, the Grooved Pegboard Test, and the Grip Strength Test. The results showed that the atypical patterns of performance indicating equal or better performance with the nonpreferred hand and large intermanual differences that exceed 10% are common in the normal Korean population. It was also found that there are larger intermanual differences in Koreans than in Canadians (Bornstein, 1986). These data strongly challenge the validity of 10% criterion in Koreans. It suggests that when manual performance tests are conducted, criteria applied to Koreans in the "restrictive" culture should be different from those applied to the people who were raised in the "permissive" culture as far as the handedness is concerned.