Manual Motor Speed Research Articles

A - 86 Using Virtual Reality Driving Simulation to Determine Cognitive Correlates of Turning Behaviors among Drivers with and without Multiple Sclerosis.

This study uses a virtual reality driving simulator (VRDS) to 1) compare turning behavior between adults with or without MS; 2) identify cognitive correlates of turning behavior. 64 community-dwelling adult drivers, including 38 people with MS (PwMS) and 26 healthy controls (HCs) (ages 21-60, 78% women, 69% White), completed neuropsychological and VRDS assessments. Key VRDS turning variables were lane position, speed, acceleration, and braking. Cross-sectional analyses included 1) analysis of variance and chi-square tests; 2) Pearson and Spearman's correlations. HCs took sharper left turns than PwMS (p < 0.05, η2 = 0.08). There were no other between-group differences. Weaker visuospatial functioning [r = -0.301, 95% CI = (-0.512,-0.050), p = 0.018], and slower gait [r = 0.0328, CI = (0.063,0.55), p = 0.014], manual motor speed [r = 0.378, CI = (0.130,0.582), p = 0.03], and psychomotor speed [r = -0.334, CI = (-0.545,-0.077), p = 0.011] were associated with greater lane position variability. Greater relative acceleration before the turn was linked to worse performance in psychomotor speed [r = 0.397, CI = (0.148,0.593), p = 0.002], time-based working memory [r = 0.452, CI = (0.221,0.631), p < 0.001], and visuoperceptual judgment time [r = -0.482, CI = (-0.660,-0.244), p < 0.001]. Slower cognitive/motor speed and poorer visuospatial abilities/memory were associated with slower driving and more braking (all p < 0.05). Drivers with and without MS exhibited similar turning behavior, but PwMS were more cautious during left turns, possibly reflecting a compensatory strategy. Despite few group differences, several cognitive domains commonly affected by MS were associated with turning behaviors. Slower cognitive/motor speed and worse visuospatial abilities were associated with less smooth control of spatial position and less safe turn preparation, but slower driving. Future studies will include larger samples and other clinical populations and may inform clinical driving recommendations.

Is processing speed a valid neurocognitive endophenotype in bipolar disorder? Evidence from a longitudinal, family study

BackgroundSubstantial evidence supports the existence of neurocognitive endophenotypes in bipolar disorder (BD), but very few longitudinal studies have included unaffected relatives. In a 5-year, follow-up, family study, we have recently suggested that deficits in manual motor speed and visual memory could be endophenotype candidates for BD. We aimed to explore whether this also applies to processing speed. MethodsA sample of 348 individuals, including 163 BD patients, 65 unaffected first-degree relatives (BD-Rel) and 120 genetically unrelated healthy controls (HC), was assessed with the Digit Symbol Substitution Test (DSST) on two occasions over a 2-year period (T1, T2). DSST values were controlled for age, years of education, occupational status, and subsyndromic mood symptoms. Differences between groups were evaluated with ANCOVAs. ResultsAt T1 BD performed significantly worse than HC (p < 0.001; Cohen's d = 1.38) and BD-Rel (p < 0.001; Cohen's d = 0.82). BD-Rel showed an intermediate performance with significant differences with HC (p < 0.01; Cohen's d = 0.50). Similarly, at T2 BD performed significantly worse than HC (p < 0.001; Cohen's d = 1.44) and BD-Rel (p < 0.01; Cohen's d = 0.51). BD-Rel performance was intermediate and significantly lower than that of HC (p < 0.01; Cohen's d = 0.97). A Repeated Measures ANOVA revealed no significant between-group differences in performance over time (p > 0.05). ConclusionsThe results of this longitudinal, family study suggest that impaired processing speed may represent a suitable cognitive endophenotype for BD. Further research on the field is required to confirm these preliminary findings.

Manual motor speed dysfunction as a neurocognitive endophenotype in euthymic bipolar disorder patients and their healthy relatives. Evidence from a 5-year follow-up study

BackgroundFew studies have examined Manual Motor Speed (MMS) in bipolar disorder (BD). The aim of this longitudinal, family study was to explore whether dysfunctional MMS represents a neurocognitive endophenotype of BD. MethodsA sample of 291 subjects, including 131 BD patients, 77 healthy first-degree relatives (BD-Rel), and 83 genetically-unrelated healthy controls (HC), was assessed with the Finger-Tapping Test (FTT) on three occasions over a 5-year period. Dependence of FTT on participants´ age was removed by means of a lineal model of HC samples, while correcting simultaneously the time and learning effect. Differences between groups were evaluated with an ANOVA test. ResultsThe patients' performance was significantly worse than that of HC over time (p≤0.006), and these deficits remained when non-euthymic BD patients (n=9) were excluded from analysis. Some significant differences between BD patients and BD-Rel (p≤0.037) and between BD-Rel and HC (p≤0.033) were found, but they tended to disappear as time progressed (p≥0.057). Performance of the BD-Rel group was intermediate to that of BD and HC. Most sociodemographic and clinical variables did not affect these results in patients. (p≥0.1). However, treatment with carbamazepine and benzodiazepines may exert a iatrogenic effect on MMS performance (p≤0.006). LimitationsOnly right-handed subjects were included in this study. Substantial attrition over time was detected. ConclusionsThere were significant differences between the patients´ MMS performance and that of healthy relatives and controls, regardless of most clinical and sociodemographic variables. Dysfunctional MMS could be considered an endophenotype of BD. Further studies are needed to rule out possible iatrogenic effects of some psychopharmacological treatments.

Multifractal temporal correlations in circle-tracing behaviors are associated with the executive function of rule-switching assessed by the Trail Making Test.

Rule switching is 1 among a diverse set of executive functions whose delicate interactions allows us to coordinate behavior appropriately to changing contexts and demands. Clinical assessments such as the Trail Making Test (TMT) estimate flexibility of rule switching, but such assessments can be challenging to interpret. TMT scores are sums of many choice response times (RTs): More time spent reflects not simply manual motor speed and visual scanning but also fluctuation of attention to sequence and less flexible switching among rules to reject many inappropriate targets and instead select the single next appropriate target. A growing consensus recognizes that the aggregate of many choice RTs reflect multiplicative interaction of factors across multiple scales, among which manual motor speed, counting up sequence, and rule-switching are just a few. Multiplicative interactions entail first, fractal temporal correlations and, more importantly, variability of fractality within the same series, that is, "multifractality," The authors analyzed circle-tracing data to test whether tracing variance, degree of fractal temporal correlations, and multifractality correlate with TMT scores. Despite the absence of effects of variance, stronger temporal correlations indicated poorer Trails B performance, but multifractality moderated this relationship. These results suggest potential markers for predicting rule-switching ability from motor behavior. (PsycINFO Database Record

Abstract T P415: Assessment Of Cognitive Symptoms In Sub-acute Stroke With An iPad Test-battery

Introduction and hypothesis: Research into the time-course of cognitive symptoms in stroke as well as planning of rehabilitation is dependent on reliable and sensitive cognitive testing. Usually, it is not possible to have all patients seen by a neuropsychologist. Moreover, a battery for stroke patients poses special challenges as symptoms like aphasia, hemineglect and hemiplegia may exclude many patients from performing a number of traditionally employed test methods. Finally, the battery has to be performed in a short timespan because many patients are easily fatigued. Method: We developed a battery comprising tests for anosognosia, aphasia, neglect, depression, episodic memory, attention span, working memory, mental speed, manual motor speed, and executive function (response inhibition). We present data from sub-acute stroke patients and age-matched controls. Both groups were tested twice with a 3 month interval in order to: 1) assess the proportion of patients able to perform the different tests; 2) determine the typical time needed to do the testing; 3) demonstrate the sensitivity to cognitive symptoms in sub-acute stroke Results: 51 stroke patients 43 healthy controls were included. 49 patients (96%) were able to do at least one test and 41 (80%) were able to do all tests. Mean duration for the testing of sub-acute stroke patients was 39 minutes (range 30-60 minutes). Mean Age 67 years (patients 65 and controls 69, range 33-90). Mean verbal fluency correct in 1st session: patients 29.2 and Controls 45.3; Mean difference 16.03, 95%CI (10.1-22.0) p 〈0.001. Mean change in patients from 1st to 2nd Session: 6.2, 95%CI(1.2-11.2) p=0.017. Mental speed by coding: patients 29.3 and controls 45.7; mean difference 16.4, 95% CI(10.3-22.4) p〈0.001. Similar analysis of memory, attention span, and executive function showed significant differences between control and patient groups as well as in patients from 1st to 2nd session. Conclusion: Our cognitive test-battery for iPad can be used with most stroke patients in the sub-acute phase. It can be performed in a relatively short time span. It is sensitive to cognitive reduction after stroke and remission of symptoms.

Neurobehavioral performance in adolescents is inversely associated with traffic exposure

On the basis of animal research and epidemiological studies in children and elderly there is a growing concern that traffic exposure may affect the brain. The aim of our study was to investigate the association between traffic exposure and neurobehavioral performance in adolescents. We examined 606 adolescents. To model the exposure, we constructed a traffic exposure factor based on a biomarker of benzene (urinary trans,trans-muconic acid) and the amount of contact with traffic preceding the neurobehavioral examination (using distance-weighted traffic density and time spent in traffic). We used a Bayesian structural equation model to investigate the association between traffic exposure and three neurobehavioral domains: sustained attention, short-term memory, and manual motor speed. A one standard deviation increase in traffic exposure was associated with a 0.26 standard deviation decrease in sustained attention (95% credible interval: −0.02 to −0.51), adjusting for gender, age, smoking, passive smoking, level of education of the mother, socioeconomic status, time of the day, and day of the week. The associations between traffic exposure and the other neurobehavioral domains studied had the same direction but did not reach the level of statistical significance. The results remained consistent in the sensitivity analysis excluding smokers and passive smokers. The inverse association between sustained attention and traffic exposure was independent of the blood lead level. Our study in adolescents supports the recent findings in children and elderly suggesting that traffic exposure adversely affects the neurobehavioral function.

Neurobehavioral function and low-level metal exposure in adolescents.

An excessive metal exposure is harmful to the brain. However, many aspects of metal neurotoxicity remain unclear including the magnitude of the low-level exposure effects and the level of exposure that can be assumed safe. The aim of our study was to investigate the association between a low-level metal exposure and three neurobehavioral domains (sustained attention, short-term memory, and manual motor speed). We measured Cd, Cu, Mn, Pb, and Tl in blood, Cd, Ni, and toxicologically relevant As in urine and methyl Hg in hair in 606 adolescents between 13.6 and 17 years of age. A two-fold increase in blood Cu was associated with a 0.37 standard deviations decrease in sustained attention (95% CI: -0.67 to -0.07, p=0.02) and 0.39 standard deviations decrease in short-term memory (95% CI: -0.70 to -0.07, p=0.02), accounting for gender, age, smoking, passive smoking, household income per capita, occupation of the parents, and education level of the mother. None of the other metals was significantly associated with the neurobehavioral domains that were measured. The observed associations between blood Cu and neurobehavioral performance are in line with recent studies in elderly. However, the relevance of our results for public health remains to be elucidated.

Computerized screening tools for neurocognitive impairment in patients with HIV infection

Neurocognitive impairment is one the non-infectious comorbidities related to HIV infection [1]. An increasing number of studies have shown the importance of assessing attention, motor, memory and cognitive functions under standardized conditions [2]. We have designed a computerized assessment tool, adapting some well-known methods of neurocognitive evaluation, and we have initiated a pilot study to assess the neurocognitive status of HIV-positive patients and controls. We assessed patients by applying the Motor Screening Task (MST: providing data on the sensorimotor function or comprehension), the Finger Tapping Test (FTT: motor function, self-directed manual motor speed), the Symbol Digit Test (SDT: divided attention, visual scanning, tracking and motor speed), and the Stroop Task (ST: selective attention and cognitive flexibility). All subjects were evaluated with this computerized set of tests during an appointment with the clinical psychologist. For statistical assessment, the T score was used. We assessed 10 HIV-positive patients and 15 controls. The median age and standard deviation were 26.5±11.5 years (range: 23-54) in the HIV group and 34±8 years (range: 25-53) in the control group. The MST scores were 720±131 ms and 629±79 ms in HIV vs. controls. The FTT scores were 167±24 ms and 163±12 ms in HIV vs. controls. The SDT scores were 6646±2905 ms and 2994±681 ms in HIV vs. controls. The ST scores were 689±92 ms, 1602±1009 ms and 2045±580 ms in the HIV group and 486±118 ms, 1041±244 ms and 1023±163 ms in the control group. Despite the low number of subjects included in the study, the T score showed a statistically significant difference between the two groups for MST, SDT, ST; no statistically significant difference was observed for FTT between the two groups. This pilot study has shown that in HIV-positive patients, the cognitive deficit tends to appear earlier than the motor one. Larger studies are needed to confirm these preliminary results and to provide more information on the clinical impact of this computerized tool for neurocognitive screening.

Neurobehavioral function and low-level metal exposure in adolescents: suggestive evidence of an association between blood copper and attention

Background It is widely acknowledged that an excessive metal exposure is harmful to the brain. However, many aspects of metal neurotoxicity remain unclear including a determination of the magnitude of the low-level exposure effects and the establishment of exposure levels which can be assumed safe. Attention and the motor function are important targets of metal neurotoxicity. Aims To investigate the association between metal exposure indicators (in blood: copper, cadmium, lead, manganese, thallium; in urine: arsenic, cadmium, nickel; in hair: methylmercury) and the neurobehavioral endpoints attention and motor speed in a group of 606 adolescents between 13.6 and 17 years of age. Methods We applied structural equation modeling, a statistical method that allows to account for measurement errors and to specify a model in terms of causal relationships. Our models took into account gender, age, socio-economic status, education of mother, education of father, and smoking behavior of the adolescents. A quadratic model was applied for the essential elements copper and manganese and a linear model for the remaining metals. Results We observed an inverted U-shape association between copper exposure and attention, p=0.002. The highest attention scores was estimated for a whole blood copper concentration of 543 µg/L (95% CI: 300-983). For a whole blood copper concentration of 1035 µg/L (the 95th percentile), the attention score was 0.50 standard deviation lower compared to the optimum level. Lead, methylmercury, toxicologically relevant arsenic, manganese, cadmium, thallium, and nickel did not show a significant association, neither with attention nor with manual motor speed. Conclusions Blood copper and attention showed an inverted U-shape association in adolescents. Our study did not provide evidence of neurotoxicity from other metals. Our results are in line with recent evidence based on adults and elderly suggesting that copper might be relevant for the neurobehavioral function in humans.

Selective neurocognitive deficits and poor life functioning are associated with significant depressive symptoms in alcoholism–HIV infection comorbidity

Alcoholism, HIV, and depressive symptoms frequently co-occur and are associated with impairment in cognition and life function. We administered the Beck Depression Inventory-II (BDI-II), measures of life function, and neurocognitive tests to 67 alcoholics, 56 HIV+ patients, 63 HIV+ alcoholics, and 64 controls to examine whether current depressive symptom level (significant, BDI-II>14 vs. minimal, BDI-II<14) was associated with poorer cognitive or psychosocial function in alcoholism–HIV comorbidity. Participants with significant depressive symptoms demonstrated slower manual motor speed and poorer visuospatial memory than those with minimal depressive symptoms. HIV patients with depressive symptoms showed impaired manual motor speed. Alcoholics with depressive symptoms showed impaired visuospatial memory. HIV+ alcoholics with depressive symptoms reported the poorest quality of life; alcoholics with depressive symptoms, irrespective of HIV status, had poorest life functioning. Thus, significant depressive symptoms were associated with poorer selective cognitive and life functioning in alcoholism and in HIV infection, even though depressive symptoms had neither synergistic nor additive effects on cognition in alcoholism–HIV comorbidity. The results suggest the relevance of assessing and treating current depressive symptoms to reduce cognitive compromise and functional disability in HIV infection, alcoholism, and their comorbidity.

Neuropsychological functioning in postmenopausal breast cancer patients treated with tamoxifen or exemestane after AC-chemotherapy: Cross-sectional findings from the neuropsychological TEAM-side study

Background. Previous studies have indicated that a subset of cancer patients treated with chemotherapy show cognitive deficits and/or experience cognitive complaints, whereas literature about the influence of hormonal therapies on cognition is sparse. Because of the accumulating knowledge about the importance of estrogen for cognitive functioning, there is growing concern about adjuvant hormonal therapy for breast cancer (BC) affecting cognition. We examined the cognitive functioning of postmenopausal BC patients who were, following doxorubicin/cyclophosphamide (AC) chemotherapy, randomized to tamoxifen or exemestane, and compared their performance with that of non-cancer controls. Materials and methods. Thirty BC patients using tamoxifen and 50 patients using exemestane underwent interviews, questionnaires and cognitive tests, on average two years after completion of AC chemotherapy. Forty eight healthy controls were tested with similar measures. Results. Memory complaints were reported by 28% of AC/tamoxifen users, 24% of AC/exemestane users and 6% of healthy controls (p=0.02). Cognitive testing revealed no statistically significant differences between tamoxifen and exemestane users, but suggested that tamoxifen use is possibly related to worse verbal functioning, while exemestane use is possibly related to slower manual motor speed. Both patient groups performed significantly worse than healthy controls on verbal fluency and information processing speed. Discussion. Our findings show that sequential treatment of AC-chemotherapy and hormonal therapy in postmenopausal, primary BC is associated with lower test scores for certain cognitive functions, and provide indications for possibly distinctive associations for different types of hormonal treatment. Future research with larger groups is recommended to obtain a more definite picture.

Multivariate structure of eye movement dysfunction distinguishing schizophrenia

The study examined processes associated with eye-movement dysfunction (EMD) maximally discriminating paranoid and nonparanoid schizophrenic subjects from psychiatric and normal controls. Measures included the linear slope of saccade number over velocities of a ramp visual target (a measure shown effectively to distinguish schizophrenia-related EMD), along with several other measures of perceptual/cognitive processes potentially contributing to oculomotor tracking. The first significant dimension, of a multiple discriminant function analysis, was one of 'EMD as related to spatial memory'. Measures of the latter reflected efficiency in encoding properties of a visual stimulus array into a task-facilitative format. The paranoid schizophrenic subgroup had the highest scores on this dimension, normals, the lowest, and depressed psychiatric controls and nonparanoid schizophrenic patients, intermediate. A second significant dimension was one of 'manual motor speed in following a ramp visual target'. Depressives were slowest, and nonparanoid schizophrenic patients fastest. Speed of the nonparanoid patients was ascribed to extrapyramidal effects, especially tremor and akathisia. The results were discussed with respect to information processing involved in oculomotor tracking, and the effects of meditation, or dyskinesia, on manual motor tracking.

Magnetic Resonance Imaging (MRI), Neurobehavioral Testing, and Toxic Encephalopathy: Two Cases

The objective of this investigation was to examine cerebral magnetic resonance imaging (MRI) pathology and functional deficits demonstrated by neuropsychological testing in cases of toxic encephalopathy. Two subjects, occupationally exposed to toxic chemicals, were studied. As part of their neurological assessment, MRI was done and each underwent a neuropsychological battery for patients with toxic exposures (White et al. Clin. Neuropharmacol. 13(5), 392–412, 1990). In Case 1, who was exposed to inorganic mercury, MRI showed mild central and cortical atrophy. Punctiform foci (T2) were noted in both frontal regions underlying the precentral gyri and in the subcortical myelin. Neuropsychological testing showed problems in cognitive flexibility, cognitive tracking, inhibiting perseveration, fine manual motor coordination, visuospatial analysis and organization, memory, and affect and personality. In Case 2, who was exposed to 2,6-dimethyl-4-heptanone, MRI showed multiple small foci in the white matter and pons. Neuropsychological testing indicated affective changes, deficits in manual motor speed, verbal fluency, visuospatial organization, and short-term memory. Lack of aphasia in patients with toxic encephalopathy indicates that neurotoxins probably affect subcortical and mesial temporal structures more than cortical gray matter. These MRI studies show subcortical sites of pathology.

Construct validity of a paper-and-pencil test of manual dexterity.

Present tests of manual dexterity are invariably designed for use as individual or smallgroup tests which require relatively cumbersome equipment for their administration. Large scale preliminary assessment of manual skills, by means of a paper-and-pencil group test, would serve a purpose similar to the one for which paper-and-pencil tests of mechanical ability were devised (e.g., the Minnesota Paper Form Board, MacQuarrie Test of Mechanical Ability). The approach has been strongly supported by Harrel (1939) who suggested that the aptitudes measured by most apparatus tests might be measured just as successfully by properly constructed paper-and-pencil tests. The intent of this study was to devise and validate a paper-and-pencil test wherein dexterity might be measured by requiring manipulation of the writing instrument itself. Four paper-and-pencil subtests were used. Two of these were designated the Preferred ITand and Non-preferred Hand subtests which required S to grasp, alternately (using left or right hand as required) a red and then a blue pencil with which he placed an x in small squares arranged in columns on a sheet. Two other subtests, designated Two-hand and Assembly tests, required the use of both hands simultaneously with two-ended, dualcolored pencils that S rotated in each hand after each marking response. Fifty undergraduate Ss were given a battery of tests consisting of the Paper and Pencil Dexterity test ( 4 subtests), the Purdue Pegboard ( 4 subtests), the Pennsylvania Bimanual Work Sample ( 2 subtests) and two tests designed to measure manual speed ( a dotting test and a line drawing test). Construct validity was determined by factor analysis of the battery and examination of the resulting paper-and-pencil test loadings in the factor structure. Of the 66 intercorrelations in the 12 X 12 matrix, all were positive and 51 were significantly greater than zero. Four meaningful factors were extracted and rotated using a varimax solution. These were identified as General Manual Skill, Fine Finger Coordinarion, Manual Motor Speed and Gross Manual Manipulation. Although the Two-hand and Assembly subtests were somewhat more highly loaded on speed than would be desired, the four paper-and-pencil subtests generally fell into a pattern of loadings with the other tests that warrants determining their predictive validity against job-performance criteria.