One of the fundamental predictions of the Adams (1971) closed-loop theory is that S should develop over practice a perceptual trace which forms the basis of an error detection mechanism. If knowledge of results (KR) is withdrawn, S can use the error detection mechanism to guide performance in its place. To test this notion, 10 Ss practiced 170 trials of a discrete ballistic response, attempting to produce a 9.5-in. manual slider movement in exactly 150 msec., with KR present except on Trials 11-20 and 141-170. There was an increasing correspondence between the actual errors and Ss' estimation of them as practice continued, and ratings of confidence increased, both of which were indicative of a developing error detection mechanism. During KR withdrawal trials, Ss displayed no worsening of performance, and even continued to learn slightly, suggesting that the error detection mechanism acted as a substitute for KR. The results generally supported Adams' theory.
[1]
William James,et al.
The consciousness of self.
,
1890
.
[2]
C. L. Hull.
Principles of Behavior
,
1945
.
[3]
E A BILODEAU,et al.
Some effects of introducing and withdrawing knowledge of results early and late in practice.
,
1959,
Journal of experimental psychology.
[4]
Edward A. Bilodeau,et al.
Acquisition of Skill
,
1967
.
[5]
M. Posner,et al.
On the genesis of abstract ideas.
,
1968,
Journal of experimental psychology.
[6]
M. Posner,et al.
Processing of visual feedback in rapid movements.
,
1968,
Journal of experimental psychology.
[7]
J. Adams,et al.
A closed-loop theory of motor learning.
,
1971,
Journal of motor behavior.
[8]
Richard A. Schmidt,et al.
The Index of Preprogramming (IP): A statistical method for evaluating the role of feedback in simple movements
,
1972
.