title: Discriminating the effects of triazolam on stimulus and response processing by means of reaction time and P300 latency.
abstract: The benzodiazepines slow information processing and the sites of this slowing were mapped using the Additive Factors Method in combination with the P300 component of the event-related brain potential. It was assumed that P300 largely reflects the time to evaluate a stimulus while reaction time (RT) reflects this time plus the time to select and execute a response. Twelve subjects were administered 0.25 mg triazolam in a repeated measures single-blind design. A visual 80-20% oddball task was used in which stimulus intensity and signal quality were manipulated with accuracy of responding held constant at a high level. RT and EEG data were collected simultaneously and the P300 elicited by the low probability stimuli was measured on a single trial basis. Triazolam slowed RT (172 ms, P < 0.0003) more than P300 (88 ms, P < 0.0007), but both measures exhibited a drug x stimulus intensity interaction. RT also exhibited a drug x signal quality interaction but P300 did not. These results suggest that triazolam has selective effects on perceptual processing by slowing an early pre-processing stage but not a later feature extraction stage. In addition, the drug appears to slow some aspect of response processing. This evidence is taken as support for a multiple process rather than a general sedation view of benzodiazepine effects on stages of processing.
authors.affiliation: Department of Psychology, York University, Ontario, Canada.
authors.forename: E
authors.initials: E
authors.lastname: Pang
authors.forename: B
authors.initials: B
authors.lastname: Fowler
mesh_terms: D000328:Adult; D004569:Electroencephalography / Q000187:drug effects*; D004585:Electrooculography / Q000187:drug effects; D005074:Evoked Potentials, Visual / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D011930:Reaction Time / Q000187:drug effects*; D016037:Single-Blind Method; D014229:Triazolam / Q000494:pharmacology*
chemical_list: D014229:Triazolam