[The dependence of motor response time in discrimination task on the type of available visual information]

The interaction of proprioceptive and visual afferentation was studied in motor task for discrimination of weights of falling objects. The availability of visual information decreased the time of motor response but to different extent depending on the kind of this information. The shortening of response time was significantly greater when subject have seen the beginning of real fall that when he simply seen the control LED signaling the release of object by electromagnet. So, subject accomplishes the task of discrimination of light and heavy object more efficiently if he sees the real falling object. This may be due to the capacity of CNS to predict the time of the impact more accurately when subject observe the initial part of real trajectory and not just an abstract visual signal.