Blood levels psychometric tests

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... 

Bellinger and Needleman (2003) reanalyzed their earlier cohort data, specifically stratifying the outcomes of the psychometric tests and dose—response strengths for 24-month PbB levels into those <10 pg/dl (N = 48) and those S 10 pg/dl. These authors reported that the dose—response slope, IQ loss versus PbB increase, was threefold steeper at PbB <10 pg/dl than for blood Pb values at 10 units or higher. This curvilinear relationship across the dose—response spectrum at lower versus higher dose has been documented in other individual and aggregated studies noted below. 

Reference Population studied N/group Age at testing, year range) Mean blood lead, pg/d range or S.D.) Psychometric tests employed Summary of results Levels of significance ... 

The present study was designed to evaluate the relationship between different biological indicators of body lead burden and some neuropsychological functions in 7-8-year-old children, living in an industrial area polluted by lead. The neuropsychological functions were estimated by a battery of 6 psychometric tests. Lead was measured in blood, hair and teeth, and mean levels of 11.45 jug dl 9.94 figg and 6.80 jUg g respectively, were obtained. 

In our study, the children recruited had been exposed to unstable conditions of lead exposure, with high levels at birth, decreasing after the first years of life. Four biochemical indicators were analysed three exposure parameters (lead in blood, hair, and teeth) and one parameter of effect (ALA-D activity). The possible relationship between current and long-term indicators was evaluated in our exposure conditions. Numerous standardized psychometric tests, selected for their sensitivity and ability to assess different cognitive functions, were carried out. 

If indices of brain function are associated with prevailing levels of psychometric intelligence one might expect them to become impaired when mental test scores are affected by prevailing blood glucose levels. In the case of reaction time (decision time and movement time) and inspection time indices this occurs, but not for nerve conduction velocity. The Hick reaction time results are now considered in more detail. Forty trials were completed at each of four levels of stimulus uncertainty (1,... 

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