Abstract
The relation of right and left brain weight to right minus left (R-L) brain weight and the relation of R-L paw use to brain weight were studied in adults cats. The R-L brain weight was significantly larger than zero in right-pawed (RH) male and left-pawed (LH) females. The R-L brain weight was significantly smaller than zero in LH males, not significantly different from zero in RH female. The R-L brain weight was negatively linearly correlated with the left-brain weigh in RH and LH males (no significant correlations in females). The R-L paw use showed a significant positive linear correlation with the R-L brain weight in RH male and females. There was a significant negative linear correlation between R-L paw use and R-L brain weight especially in LH males. Total brain weight showed a significant linear correlation with R-L paw use in RH males, and a positive linear correlation in LH males (no correlations in female cats). These results indicated that intermanual difference in paw use is associated with interhemispheric weight difference and total brain weight, especially in male cats, the left brain seems to be of importance in cerebral lateralization.