HORIZONTAL PURSUIT RIGHT-ARM MOVEMENTS AND DUAL-TASK INTERFERENCES - A REPLICATION AND EXTENSION

Twenty right-handed males had to follow a target moving horizontally w ith a velocity of 40 degrees/s either rightwards or leftwards by movin g their right arm. During this pursuit tracking movement, subjects had to perform one of three different interference tasks (concurrent spea king, concurrent verbal rehearsal and concurrent visualization of a ma ze problem). In addition, they were required to accomplish these movem ents without an interference task. It was shown that while subjects sp oke, pursuit movements rightwards were more inaccurate than movements leftwards. The other interference tasks did not generate such a direct ion specific effect. This result is in line with theories implying tha t visually guided right-arm movements rightwards are controlled by a n eural network located in the left hemisphere, whereas right-arm moveme nts leftwards are controlled by a neural network distributed over both hemispheres.