Silverman, and Charlotte Christner assisted in collecting the data here reported.

assisted in collecting the data here reported. ' Theorem 17 states that "the capacity of a channel of band W perturbed by white thermal noise of power N when the average transmitter poser is limited to P is given by P+N" C-W log-^-(22, p. 67). W is in cycles per second and takes the form of the reciprocal of some value of time. The power of a band of noise is equivalent to the variance of its amplitude distribution around its mean value.

The effects of response amplitude and terminal accuracy on 2-choice reaction time (RT) and on movement time (MT) were studied. Both the required amplitude (A) of a movement, and the width (W) of the target that S was required to hit, had a large and systematic effect on MT, whereas they had a relatively small effect on RT. Defining an index of movement difficulty as ID = log^B2)2A/W, the correlation between ID and MT was found to be above .99 over the ID range from 2.6 to 7.6 bits per response. Thus the times for discrete movements follow the same type of law as was found earlier to hold for serial responses. The relative independence of RT and MT is interpreted as pointing to the serial and independent nature of perceptual and motor processes. (17 ref.)

The hypothesis that information transfer in a perceptual-motor task is in a large measure a function of the matching sets of stimuli and sets of responses was tested. The results, analyzed in terms of reaction time, errors, and information lost, support the hypothesis. A further experiment was run to test the performance of three selected S-R compatibility effects. It was found that in making a particular set of responses to each of three sets of stimuli, differences in reaction time, movement time, and frequency of errors persisted over the entire 32 days of testing.

No abstract