24-40 In our hands, a 0.5-mg subcutaneous injection of scopolamine in young HVs induced impairment, in immediate and delayed word recall, multiple choice reaction time and accuracy, and the digit symbol substitution test. In quantified EEG, it. reduced total power and induced an

increase in S and a decrease in 6, a, and p absolute power; in relative power analysis, the 8 and p band activity was increased and that of the 6 and a bands decreased (Figure 1.) An interesting feature of this model is that is can be reversed or prevented not. only by cholinomimetic drugs, but. also, as we have found, by compounds Inhibitors,research,lifescience,medical without direct, cholinergic effects.30,31,38,41 Figure 1. Effect of scopolamine (0.5 mg subcutaneously)on Bioactive Compound Library nmr electroencephalogram (EEG) in 12 healthy young men. Placebo and scopolamine were administered according to a crossover, double-blind design. Inhibitors,research,lifescience,medical EEG was recorded from 28 electrodes during the first 3 min in … The lorazepam model Benzodiazepines (BZDs) are known to induce sedation, psychomotor impairment, and anterograde amnesia, leaving retention and retrieval spared.42 Although cognitive impairment is

a class effect, differences between different BZDs have been reported, independently of their elimination half-lives.43-45 A dissociation Inhibitors,research,lifescience,medical between the cognitive and sedative effects of drugs has also been described.46 Lorazepam has dose-related memory- and attention-impairing effects.43,44,47 It has been suggested48 that the profile of lorazepam-induced Inhibitors,research,lifescience,medical cognitive impairment is close to that observed in Korsakoff’s syndrome, whereas scopolamine rather mimics AD. Some studies47,49 were unable to distinguish the effects of lorazepam from those

of scopolamine. Both drugs were Inhibitors,research,lifescience,medical shown to have similar effects on verbal priming50 and in a face-name associative encoding task,51 and as well as on associated functional magnetic resonance imaging (fMRI) activation patterns. On the other hand, differential effects were found on logical reasoning, immediate and delayed recall,52 and priming for human faces.53 BZDs have well-known effects on EEG. Changes in p amplitudes seem to reflect their interaction and intrinsic efficacy at the GABAA-BZD (GABA, y-aminobutyric acid) receptor complex; their effects on p and a activity their anxiolytic, anticonvulsant, and sedative properties; and Carnitine palmitoyltransferase II 8-induced changes their hypnotic action.54 In our hands, an oral dose of 2 mg lorazepam impaired immediate and delayed word recall, multiple choice reaction time and accuracy, and digit, symbol substitution test, but. had no effect, on flicker fusion frequency. In quantified EEG, lorazepam’s effects were dose -dependent in length and intensity, increasing 8 and P power, and decreasing the power of the 6 and a frequency bands (Figure 2.) Figure 2. Effects of three oral doses of lorazepam on electroencephalogram (EEG) in 20 young healthy male volunteers. Lorazepam 0.