Abstract
The effects of two kinds of benzodiazepines, temazepam and nitrazepam, on internal processing stages associated with reactive skills were tested using a single performance test consisting of three types of reaction time (RT) tasks differing in response-certainty. The experiment was carried out double blind on two consecutive days for three treatment groups, eight subjects each, including a placebo group. The results indicated that: 1) a drug effect appeared not in the measure of mean RTs, but in that of RT variances, 2) this effect tended to spread over the whole stages of processing, 3) the mental process most affected would be the cognitive one related to response selection; however, this resulted from the task characteristics such as certainty rather than from drug intake. It was suggested that the drugs would act to impair the processes that regulated organized responses as a whole, not specifically any definite stage of signal processing.