Dynamics of assessments of time intervals by patients with heroin addiction.

The perception of 12-sec time intervals time by patients with heroin addiction was assessed in 10 trials with precision of up to 0.1 sec. A total of 82 patients with heroin addiction were studied in the withdrawal and post-withdrawal periods. The results obtained in patients were comparable to measurements obtained in 52 healthy subjects. The time interval estimated by patients as an overall group was shorter than that in healthy subjects during the first two days of in-patient treatment (during development of withdrawal syndrome); the 12-sec period was reproduced accurately at 5-6 days, after which the period was exceeded; perception of time again became accurate on days 15-16 (the post-withdrawal period). Changes in the subjective perception of time were found to depend on the duration of addiction and the individual characteristics of interhemisphere brain asymmetry.