Lateralized interference of repetitive finger tapping: influence of familial handedness, cognitive load and verbal production.

The repetitive finger tapping of 24 right-handed subjects from dextral and sinistral families was evaluated. Subjects tapped with and without concurrent verbal tasks which included reciting a nursery rhyme, reading words (silent vs aloud) and solving anagrams (silent vs aloud). Overall, results indicated that the concurrent verbal tasks interfered more with right-hand tapping than with left-hand tapping. This pattern was more pronounced for familial dextral subjects than familial sinistral subjects. This latter finding was most evident with the complex verbal task of solving anagrams.