[Concentration on a task and change in pulse rate and finger skin blood flow (author's transl)].

Eight subjects were given a pursuit tracking task (Exp. I), a continuous task involving the adding of digits (Exp. II), and the Uchida-Kraepelin psychodiagnostic test (Exp. III). Experiments I and II employed distributed practice. Finger Skin Blood Flow (SBF) and Pulse Rate (PR) were measured during the experiments. It was found that SBF was smaller during trials than during intertrial rests, the latter being smaller than rests with eyes closed. SBF was smallest during the first trial (Exp. I & II) or the first minute (Exp. III). PR reversed direction with some differences being observed between the changes in PR and SBF. The results indicate that concentration on a task is reflected better by SBF than by PR.