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The counterintuitive developmental trend in the Deese-Roediger-McDermott (DRM) illusion (that false-memory responses increase with age) was investigated in learning-disabled and nondisabled children from the 6- to 14-year-old age range. Fuzzy-trace theory predicts that because there are qualitative differences in how younger versus older children and disabled versus nondisabled children connect meaning information across the words on DRM lists, certain key effects that are observed in adult studies will be absent in young children and in learning-disabled children. Data on 6 such adult effects (list strength, recall inflation, delayed inflation, delayed stability, thematic intrusion, and true-false dissociation) were used to investigate this hypothesis, and the resulting data were consistent with prediction.

False memories have typically been found to be more common during early childhood than during later childhood or adulthood. However, fuzzy-trace theory makes the counterintuitive prediction that some powerful forms of adult false memory will be greatly attenuated in early childhood, an important example being the Deese/Roediger/McDermott (DRM) illusion. Three developmental studies of this illusion (N = 282) found that (1) it was at near-floor levels in young children, (2) it was still below adult levels by early adolescence, and (3) the low levels of the illusion in young children may be due to failure to "get the gist" of DRM materials. [ABSTRACT FROM AUTHOR]

The pharmacokinetics of the cholinesterase inhibitor pyridostigmine has been studied in six male Beagle dogs after iv infusion and after oral doses as an immediate-release syrup and as an extended-release tablet, all at a level of approximately 0.6 mg/kg. Pyridostigmine was characterized as a drug of relatively long terminal half-life (8.3 h +/- 2.1 SD), low systemic clearance (13 mL/min/kg +/- 1 SD) and high volumes of distribution (Vd lambda z, 8.7 L/kg +/- 1.9 SD and Vdss, 3.9 L/kg +/- 0.9 SD). The ratio of mean residence times in tissues and plasma was greater than 4, indicating a high affinity of peripheral tissues for the drug. This ratio was about twofold higher in three of the dogs than in the others. Pyridostigmine was slowly and incompletely bioavailable in these dogs; the systemic availability was 44.4% +/- 4.3 SD from the syrup and 33.6% +/- 9.5 SD from the tablet. Pyridostigmine disposition in these dogs was largely determined by distribution processes.

The development, validation, and application of a new radioimmunoassay for haloperidol in biological fluids is described. The antiserum, raised against N-amino-butyl chlorophenyl piperidine bovine albumin conjugate, could not distinguish between haloperidol and its reduced metabolite, but it could discriminate against chlorophenyl piperidine (cross-reaction 2.6%). The fluorophenyl metabolites of haloperidol were not recognized by the antiserum. Haloperidol determinations were made on less than 100 microliter aliquots of human and rhesus monkey plasma or diluted urine without prior extraction of the sample. The radioimmunoassay was applied to the study of the pharmacokinetics of intravenous haloperidol administration to two male rhesus monkeys. Salient features of the results are as follows. As with man, the plasma concentration versus time curve could be resolved into three compartments, but there were differences in the distribution of haloperidol between the compartments. The apparent volume of distribution for the two monkeys examined was 5.87 L kg-1 and 7.37 L kg-1, considerably smaller than in man, a difference almost entirely due to a much smaller tissue compartment. The biological half-life of 15.97 hr and 7.56 hr was similar to man. The mean hepatic extraction ratio was calculated to be 0.032 and 0.056, and the data suggested that hepatic metabolism of haloperidol may be of lesser importance in rhesus monkey than in man. An insignificant proportion (0.01%) of the administered dose was excreted as haloperidol in the urine.