Asymmetrical transfer of training between hands: implications for interhemispheric communication in normal brain

Area of Science:

• Neuroscience
• Cognitive Psychology
• Motor Control

Background:

• Investigating interhemispheric interaction and transfer of training between hands.
• Examining the influence of hand dominance on motor skill acquisition and transfer.
• Exploring models of brain hemisphere communication in relation to motor learning.

Purpose of the Study:

• To investigate claims of asymmetrical transfer of training between hands/hemispheres.
• To compare same-hand transfer with opposite-hand transfer in a printing task.
• To evaluate existing models of interhemispheric interaction against experimental findings.

Main Methods:

• Experiment 1: 96 right- and left-handed male undergraduates practiced an inverted-reversed printing task with either the right or left hand.
• Experiment 2: 176 right-handed children aged 7, 9, and 11 years were tested.
• Data analysis focused on comparing transfer effects between hands and across different handedness groups.

Main Results:

• For right-handed subjects, the left hand demonstrated greater benefit from opposite-hand training than the right hand.
• Left-handed subjects in Experiment 1 showed the reverse pattern, with the right hand benefiting more from left-hand training.
• One subgroup of left-handers exhibited minimal transfer in either direction, indicating task-specific or individual differences.

Conclusions:

• Current models of interhemispheric interaction do not fully account for the observed asymmetrical transfer patterns.
• A cross-activation model may offer a more suitable framework for explaining these findings.
• The study highlights complex hemispheric interactions in motor learning that vary with handedness and potentially task specifics.