[Effect of mental work on the efficiency and reliability of voluntary motor activity].

By means of reflexometry 200 students were divided into three groups -- with high, medium and low work efficiency (WE) and mobility of cortical processes (MCP) and into three initial variations within each group. After studies WE and MCP change in the direction opposite to the initial in extreme variations and remain at the initial level in the mean variation. Direct correlation between WE and MCP and work reliability (WR) is found which is independent of the degree of their pronouncement.