Comparison of Dichotic Consonant- Vowel test results between right handed and left handed adults with normal hearing

Introduction: According to the previous studies, left hemisphere of the brain has specialized for language processing. The relation between handedness and the brain hemispheres is very obvious. In more than 95% of right- handed people and 70% of left- handed people the left hemisphere is responsible for language processing generally. A few studies have investigated the relationship between handedness and the brain hemispheres by means of Dichotic Consonant- Vowel ( DCV ) test. The aim of the present study is to investigate the results of DCV test in right- handed and left- handed adults with normal hearing.Methods:  40 right- handed and 40 left- handed adults aged between 18- 40 years whose handedness was verified by Edinburgh scale participated in this study. This research was performed at rehabilitation faculty, ShahidBeheshti University of medical sciences.  DCV test results were analyzed t- test parametric and Mann- Whitney non- parametric statistical tests.Results: Right- handed group scores were more than left- handed group scores which was meaningful statistically ( p≤ 0.01 ). The percentage of double corrected consonant- vowels in right- handed group was more than this in left- handed group.Conclusion: The results of the present study indicate that right- handed group function is better than left- handed group function in the DCV test. Right ear advantage is obvious not only in right- handed group but also in left- handed one which shows left hemisphere advantage in processing the linguistic information.Keywords: Right- handedness, left- handedness, dichotic consonant- vowel test