Computerized measures of finger tapping: effects of hand dominance, age, and sex.

Computerized measures of digit tapping rate were obtained over 3 successive, 10-sec. periods in the right and left index fingers, from a community sample of 1,519 participants (ages 18 to 65 years; 607 men, 912 women). Differences between the dominant and non-dominant hands were found for tapping rate, movement initiation, and button down times, and the decline in tapping rate over the successive, 10-sec. periods. Declines were found in tapping rate in older participants in association with increased intertap variability. Men had higher tapping rates than women in all age ranges. The computerized finger tapping test is an efficient and precise measure of tapping speed and kinetics of potential utility in research and clinical studies of motor performance.

Drinking course through midlife based on diagnostic versus quantity-frequency indices.

BACKGROUND: Prior efforts to examine the course of drinking from onset to midlife have been limited to analyses of year-to-year changes in alcohol dependence (AD). The current investigation sought to examine the course of drinking over this time frame using consumption-based measures of drinking and evaluate the degree of comparability in trajectories estimated from diagnostic and quantity-frequency data. METHODS: Participants included 420 men with a lifetime history of AD who were drawn from the Vietnam Era Twin Registry and administered the Lifetime Drinking History, which provided person-year (retrospective) data on patterns of consumption and diagnostic symptoms from drinking onset to participants' current age. Consumption-based data were aggregated into age categories that ranged from "up to age 20" to "ages 54 to 56" and analyzed separately as a dichotomous measure of "heavy drinking (HD)" and continuous quantity-frequency index (QFI) scores. RESULTS: Using latent growth mixture modeling, trajectories based on the HD measure were moderately concordant with those based on changes in AD that were previously identified in this sample, whereas trajectories based on QFI scores were only weakly related to those based on AD diagnoses. Moreover, examination of the degree of concordance between AD- and QFI-derived trajectories revealed that measures of consumption (and potentially other continuous indices of drinking) may qualify past interpretations of various developmental trajectories that have been discussed in the alcoholism typology literature (particularly "Late Onset" alcoholism). CONCLUSIONS: Collectively, the findings highlight the importance of integrating repeated measures of alcohol consumption in future efforts to describe the course of drinking across the life span.

Computerized measures of finger tapping: reliability, malingering and traumatic brain injury.

We analyzed computerized finger tapping metrics in four experiments. Experiment 1 showed tapping-rate differences associated with hand dominance, digits, sex, and fatigue that replicated those seen in a previous, large-scale community sample. Experiment 2 revealed test-retest correlations (r = .91) that exceeded those reported in previous tapping studies. Experiment 3 investigated subjects simulating symptoms of traumatic brain injury (TBI); 62% of malingering subjects produced abnormally slow tapping rates. A tapping-rate malingering index, based on rate-independent tapping patterns, provided confirmatory evidence of malingering in 48% of the subjects with abnormal tapping rates. Experiment 4 compared tapping in 24 patients with mild TBI (mTBI) and a matched control group; mTBI patients showed slowed tapping without evidence of malingering. Computerized finger tapping measures are reliable measures of motor speed, useful in detecting subjects performing with suboptimal effort, and are sensitive to motor abnormalities following mTBI.