Error Correction Time without External Error Signals

HUMAN subjects carrying out continuous performance choice response tasks are often required to correct any error by immediately making the response which they should have made. Two recent studies1,2 have shown that such “error correcting responses” are faster than other, equivalent, correct responses. In both these investigations the occurrence of any error was signalled to subjects by the equipment on which they were tested. Either the display failed to change1 or the same signal was repeated after a brief interval2. In the latter case2 the times taken to respond and correct the error were even shorter than the response times when the same signal was repeated immediately after a correct response. Nevertheless, the fact the responses to error signals were faster than responses to any other signals from the display does not lead logically to the conclusion that they are not responses to external signals. We have investigated the time taken to correct errors when no indication was given by the equipment when errors were made, so that subjects were dependent for this information on their ability to monitor their own responses.