Critical Fusion Frequency

A double-blind crossover study in 12 healthy subjects found that a transdermal hyoscine preparation (Scopoderm-TTS) did not alter the effects of alcohol on the performance of several psychometric tests (Critical Flicker Fusion Frequency, Choice Reaction Tasks), nor was the clearance of alcohol or hyoscine changed. Blood-alcohol levels of up to 80 mg%, and 130 mg%, were studied. Nevertheless, the manufacturer suggests... 

Smart JV, Turner P. Influence of urinary pH on the degree and duration of action of amphetamine on Ae critical flicker fusion frequency in man. BrJ Pharmacol (196 26,468-72. 

Meyer-Lindenberg etal, (1997) evaluated the psychometric effects of sulpiride in comparison with placebo in 12 healthy volunteers using time estimation, critical flicker fusion, and choice reaction tasks at baseline and 4h after oral administration of either 300 mg of sulpiride or placebo. Critical flicker fusion frequency was lower and choice-reaction decision time was prolonged under medication. Choice reaction movement time was not altered. 

Critical Flicker Fusion Determination of the lowest frequency at which a flickering on-off light appears to be constant 7 18... 

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