Sompop Soo-Ampon. Psychometrics in psychopharmacology : the measurement of CNS active drugs. Doctoral Degree(Pharmacology). Mahidol University. : Mahidol University, 2009-07-09.
Psychometrics in psychopharmacology : the measurement of CNS active drugs
Abstract:
The purposes of this thesis were to determine the sensitivity of psychometric tests to the effects of drugs, and investigate some of the methodological issues that can influence the integrity of test outcomes. A critical review on the sensitivity of psychometric tests revealed that tests of sensorimotor coordination showed the highest sensitivity to discriminate between drugs as regards their potential to cause cognitive and psychomotor impairment. In investigation of the current battery of psychometric tests consisted of critical flicker fusion (CFF), choice reaction time (CRT), continuous tracking (CTT), Sternbergs scanning memory (SMS), rapid visual information processing (RVIP), brake reaction time, and subjective line analogue rating scale assessments, positive controls including alprazolam 1 mg tid, promethazine 25 mg, and lorazepam 2 mg with alcohol 0.6 g/kg were examined. The results suggest that this test battery is able to detect the impairment on performance of the positive controls. From the investigation of practice effect, it can be seen that no practice effect was observed in the CFF while the CRT, CTT, SMS, RVIP, mental arithmetic, and Stroop tasks exhibited practice effects. This result suggests that it is essential to preclude practice effect by giving the proper familiarisation to subjects. In the study of effect of task duration on CTT performance, the results showed that alprazolam 1 mg tid, lorazepam 2 mg, and promethazine 25 mg increasingly impaired CTT performance over time (until about 7.5 min), but that a plateau was reached by 10 min for promethazine 25 mg. In contrast, following placebo,
performance on the CTT was stable at 7.5 min but had deteriorated by 10 min. These data suggest that performance on CTT tasks should take account of task duration. Effects of word frequency (frequency of occurrence in everyday language) on word recall task following lorazepam 2 mg with alcohol 0.6 g/kg was examined. The results showed that low-frequency words were more sensitive to memory impairment
than high-frequency words. These findings indicate that word frequency has a significant impact on assessment of drug effects on recall memory. From the overall findings, it can be proposed that a more systematic approach to test usage among researchers should be introduced. Indeed, such an approach would
facilitate the development and standardization of psychometric