We did not find any significant associations between serum levels of BFR and performance in the Continuous Performance, Digit-Symbol or Digit Span tests (Table 4).
We were interested in performance on digit span backward, which is considered a measure of executive or complex working memory (George & Coch, 2011).
APOE 4 females had higher BMI and females with normal BMI between 75 94% percentiles had the highest deficits in Total IQ, Performance IQ, Digit Span, Picture Arrangement, Block Design and Object Assembly.
Furthermore, IL-6 level has been found to predict worse cognitive performance in Digit Symbol Coding test in the elderly [ 46] and type 2 diabetes elders [ 47].
One study found that women with lower estrone levels had significantly better performance on Digit Symbol compared with women with higher estrone levels [ 73].
This group trended towards poorer performance on digit span backwards (t = 1.9, df = 37, p = 0.065) and trails B errors (t = 1.88, df = 32, p = 0.069).
Performance on digit and letter identification in hidden object tasks was assessed by computing the d' parameter from signal detection theory, as the difference between z scores for hits and false alarms (d' = zhit – zfalse alarm).
Additional post hoc multiple regressions of individual NP tests on the predictor set revealed significant inverse relationships of precuneus PiB retention with performance on Digit Span Backward, CAT, FRsrt, FCsrt, BNT, VFDT, and CDR-sum of box score.
Chi-square and Fisher's exact test, as appropriate, were applied for comparison of infection, morbidity and low performance in digit span test proportions between different groups in the main analysis and the attrition analysis.
In a study of 89 workers (42 exposed and 47 control), urinary cadmium was significantly associated with poor visuomotor performance (symbol digit substitution and simple reaction time tests), even after adjusting for age, alcohol, exposure to other neurotoxicants, neuroactive medications, and years of schooling [ 3].
