Left-handers, retrained left-handers and right-handers: A comparative study

Present study was aimed at further extension of the scientific data concerning the influence of retraining in left-handers as well as concerning some disabilities ascribed to the left-handedness. Study participants filled in the questionnaire about the incidence of fears and depression, bedwetting and stuttering, spatial confusion, complaints on weak memory and attention. Responses were analyzed regarding the handedness of the respondents, qualified as left-hander, right-hander and retrained left-hander. The number of reports on bedwetting and slowness in writing, as well as on spatial left/right confusion was found higher in left-handers as compared to right-handers. The number of reports on fears was found higher in retrained left-handers. Left-handers, retrained left-handers and right-handers did not differ in the number of reports on stuttering, depression, week memory and not sustained attention.  Mental rotation task performance was studied in another group of left-handed and right-handed participants. Handedness was determined by the test on hand performance. Left-handers were found to make more mistakes in mental rotation task performance as compared to right-handers. We conclude that expectancy of bedwetting, slowness in writing and mental spatial left/right confusion is higher in left-handers as compared to right-handers. Retraining of left-handers is suggested to cause fears, however it is not related to stuttering, depression, slowness in reading and writing, worsening of memory and attention. Stuttering is equally expectable among left-handers, retrained left-handers and right-handers.