Cognition measurement

A study of experienced cannabis smokers tested them on cognitive measures using two doses (1.75% or 3.55%) and placebo (Wilson et al. 1994). The functions most sensitive to the effects of THC were mental processing speed (digit-symbol substitution) and reaction time. When compared with cannabis nonusers, chronic users of cannabis—with a mean duration of use of 6.76 years and an average daily intake of 150 mg of THC—were found to have slower reactions on perceptuo-motor tasks, but no differences on intelligence or memory tests (Varma et al. 1988). 

During 1961, we dropped some performance fasks and added others. My co-workers and I tried out a battery of six cognitive measures - the so-called Texas Battery developed by Moran and Mefford in 1959. The designers had identified six basic cognitive skills, using factor analysis. To allow repeated administration of their brief (fcee minute) tests while minimizing practice effects, they created 20 equivalent forms for each cognitive skill. 

We tested a variety of military skills in this pilot study. Motion picture documentation of performance was provided and used to produce a film (Soldier s Predicament). The aim of this pilot study was to examine the relationship between performance of military tasks such as rifle assembly and map reading, to cognitive measures such as NF, SC and VITA As expected, the performance ability of well-trained soldiers was grossly inadequate and completely impossible during periods of incapacitation, as indicated by their cognitive test scores. The relevance of laboratory measures to simulated military performance was reinforced by these results. 

Campbell, M., and Plij, M. (1985) Behavioral and cognitive measures used in psychopharmacological studies of infantile autism. Psy-chopharmacol Bull 21 1047-1053. 

F. What is the treatment plan B, C, and D as well as cognitive measures and coping skills measures... 

As a result of this complexity, skin smoothness is therefore difficult to assess globally in an objective manner. At present, attempts to quantify this cosmetically important quality are only partial, either through a purely physical approach (friction measurement), or by objective cognitive measurements (brain activity) or psycho-physical tests. 

High potency typical P No changes in PANSS or cognitive measures... 

Acetyl-L-carnitine has been shown to cause a slowdown in the decline of cognitive measures in a number of studies conducted on subjects with mild Alzheimer s disease or mild cognitive impairment. However, one of the most recent double-blind trials conducted on its use in Alzheimer s showed very little difference between acetyl-L-carnitine and placebo. A recent metaanalysis of all the double-blind controlled clinical trials of acetyl-L-carnitine concentrated on patients who had mild cognitive impairment or mild Alzheimer s, and found that of 21 studies conducted, 17 showed that it had a positive effect on patients this however included some unpublished trials. 

Though one can argue about methods, there is little doubt about the general conclusion. No matter how the data are analysed, no matter if the methods are conservative or liberal, no matter what test of intelligence is used, a set of cognitive measures can predict IQ as well as IQ tests predict each other. This is... 

Pope HG, Gruber AJ, Hudson JI, et al (2002) Cognitive measures in long-term cannabis users. J Clin Pharmacol 42 41-47S... 

Corey DA, Juarez de Ku LM, Bingman VP, et al. 1996. Effects of exposure to polychlorinated biphenyl (PCB) from conception on growth, and development of endocrine, neurochemical, and cognitive measures in 60 day old rats. Growth Dev Aging 60 131-143. 

The sample in the main Seychelles study appears to have been developmentally robust. There was an exceptionally low number of abnormal scores on the Denver Developmental Screening Test, an unusually high mean Psychomotor Development Index score, and a very low rate of referral for mental retardation. On the other hand, the means and standard deviations of the cognitive measures administered at later ages were similar to U.S. norms. It is unclear to what extent the developmental robustness of that particular sample might have buffered it from any adverse effects of prenatal Hg exposure. 

As for receivers characteristics, these contain demographic variables such as gender, age, work seniority, cultural and educational background, product or task familiarity and training, and individual differences. The researches on individual issue focus on the Need for Cognition measured... 

Psychological The potential effects of triazolam on cognitive performance have been studied in a double-blind, placebo-controlled comparison of the acute effects of triazolam and alcohol in 20 social drinkers [15 ]. Triazolam was more likely to impair several objective measures of cognitive performance, such as episodic memory and divided attention, and it also slowed performance across several cognitive measures. Triazolam alone impaired other measures of metacognition, such as error detection on a choice reaction time task. 

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