Necessity of technicians for computerized neuropsychological assessment devices in multiple sclerosis.

OBJECTIVE: Determine the influence of technician supervision on computer-administered cognitive tests in multiple sclerosis (MS). METHODS: Eighty MS patients underwent assessment using the CogState Brief Battery (CSBB) and the Cleveland Clinic Cognitive Battery (C3B). Each was administered twice, once with a technician guiding assessment, and once with technician-absent. Twenty-eight healthy controls were also evaluated. RESULTS: The influence of technician guidance was not statistically significant for group means on either test. For CSBB, administration problems were more common in the technician-absent condition. CONCLUSION: In this MS sample, reliable and valid test results were obtained from computer-assisted cognitive testing without technician guidance.

ENHANCE: a comparative prospective longitudinal study of cognitive outcomes after 3 years of hearing aid use in older adults.

Background: With an aging population, the prevalence of hearing loss and dementia are increasing rapidly. Hearing loss is currently considered the largest potentially modifiable risk factor for dementia. The effect of hearing interventions on cognitive function should therefore be investigated, as if effective, these may be successfully implemented to modify cognitive outcomes for older adults with hearing loss. Methods: This prospective longitudinal observational cohort study compared outcomes of a convenience sample of prospectively recruited first-time hearing aid users without dementia from an audiology center with those of community-living older adults participating in a large prospective longitudinal cohort study with/without hearing loss and/or hearing aids. All participants were assessed at baseline, 18 months, and 36 months using the same measures. Results: Participants were 160 audiology clinic patients (48.8% female patient; mean age 73.5 years) with mild-severe hearing loss, fitted with hearing aids at baseline, and 102 participants of the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Aging (AIBL) (55.9% female patient; mean age 74.5 years). 18- and 36-month outcomes of subsets of the first participants to reach these points and complete the cognition assessment to date are compared. Primary comparative analysis showed cognitive stability for the hearing aid group while the AIBL group declined on working memory, visual attention, and psychomotor function. There was a non-significant trend for decline in visual learning for the AIBL group versus no decline for the hearing aid group. The hearing aid group showed significant decline on only 1 subtest and at a significantly slower rate than for the AIBL participants (p < 0.05). When education effects on cognitive trajectory were controlled, the HA group still performed significantly better on visual attention and psychomotor function (lower educated participants only) compared to the AIBL group but not on working memory or visual learning. Physical activity had no effect on cognitive performance trajectory. Conclusion: Hearing aid users demonstrated significantly better cognitive performance to 3 years post-fitting, suggesting that hearing intervention may delay cognitive decline/dementia onset in older adults. Further studies using appropriate measures of cognition, hearing, and device use, with longer follow-up, are required.

A pilot evaluation of a computer-based psychometric test battery designed to detect impairment in patients with cirrhosis.

BACKGROUND: Psychometric testing is used to identify patients with cirrhosis who have developed hepatic encephalopathy (HE). Most batteries consist of a series of paper-and-pencil tests, which are cumbersome for most clinicians. A modern, easy-to-use, computer-based battery would be a helpful clinical tool, given that in its minimal form, HE has an impact on both patients' quality of life and the ability to drive and operate machinery (with societal consequences). AIM: We compared the Cogstate™ computer battery testing with the Psychometric Hepatic Encephalopathy Score (PHES) tests, with a view to simplify the diagnosis. METHODS: This was a prospective study of 27 patients with histologically proven cirrhosis. An analysis of psychometric testing was performed using accuracy of task performance and speed of completion as primary variables to create a correlation matrix. A stepwise linear regression analysis was performed with backward elimination, using analysis of variance. RESULTS: Strong correlations were found between the international shopping list, international shopping list delayed recall of Cogstate and the PHES digit symbol test. The Shopping List Tasks were the only tasks that consistently had P values of <0.05 in the linear regression analysis. CONCLUSION: Subtests of the Cogstate battery correlated very strongly with the digit symbol component of PHES in discriminating severity of HE. These findings would indicate that components of the current PHES battery with the international shopping list tasks of Cogstate would be discriminant and have the potential to be used easily in clinical practice.

A probability based approach for the allocation of player draft selections in Australian rules football.

Australian Rules Football, governed by the Australian Football League (AFL) is the most popular winter sport played in Australia. Like North American team based leagues such as the NFL, NBA and NHL, the AFL uses a draft system for rookie players to join a team's list. The existing method of allocating draft selections in the AFL is simply based on the reverse order of each team's finishing position for that season, with teams winning less than or equal to 5 regular season matches obtaining an additional early round priority draft pick. Much criticism has been levelled at the existing system since it rewards losing teams and does not encourage poorly performing teams to win matches once their season is effectively over. We propose a probability-based system that allocates a score based on teams that win 'unimportant' matches (akin to Carl Morris' definition of importance). We base the calculation of 'unimportance' on the likelihood of a team making the final eight following each round of the season. We then investigate a variety of approaches based on the 'unimportance' measure to derive a score for 'unimportant' and unlikely wins. We explore derivatives of this system, compare past draft picks with those obtained under our system, and discuss the attractiveness of teams knowing the draft reward for winning each match in a season. Key PointsDraft choices are allocated using a probabilistic approach that rewards teams for winning unimportant matches.The method is based upon Carl Morris' Importance and probabilistic calculations of making the finals.The importance of a match is calculated probabilistically to arrive at a DScore.Higher DScores are weighted towards teams winning unimportant matches which in turn lead to higher draft selections.Provides an alternative to current draft systems that are based on 'losing to win'.

Cognitive evolution in natalizumab-treated multiple sclerosis patients.

BACKGROUND: Cognitive dysfunction affects up to 65% of multiple sclerosis (MS) patients and progresses over time. Natalizumab has been shown to be superior to placebo in preserving cognition for the first two years of therapy. OBJECTIVES: The objectives of this study are to understand the impact of natalizumab on cognition beyond two years of therapy and to investigate whether baseline characteristics are predictive of clinical response. METHODS: This is a single-center, 24-month, observational study. Sixty-three patients treated with natalizumab were assessed prior to monthly infusions using a Cogstate battery and the Symbol Digit Modalities Test (SDMT). Patient demographics were collected at baseline. A linear mixed model was conducted with duration of natalizumab therapy as a between-subjects factor (≤2 or >2 years), assessment as a within-subjects factor, and Multiple Sclerosis Severity Score (MSSS) as a covariate. RESULTS: Aside from the MSSS (p = 0.0074), the two groups were identical. No patient showed evidence of sustained cognitive deterioration over the 24-month period. Baseline parameters including impaired cognition did not influence the trajectory of cognitive change over 24 months. CONCLUSIONS: Our results suggest that natalizumab preserves cognition following four to seven years of continuous therapy. This occurs irrespective of baseline characteristics, including impaired cognition.

The nature and rate of cognitive maturation from late childhood to adulthood.

To better understand the nature and rate of cognitive change across adolescence, the Cogstate Brief Battery (CBB) was utilized to assess psychomotor function, attention, working memory, and visual learning in individuals aged 10-18 years old. Since all CBB tasks have equivalent perceptual, motor, and linguistic demands as well as being appropriate for both children and adults, this approach allowed direct across-age comparison of multiple cognitive domains. Exponential decreases in reaction time and linear increases in accuracy were observed across adolescent development in a cross-sectional sample of 38,778 individuals and confirmed in a 5788 individual longitudinal sample with 1-year repeat assessments. These results have important implications for the repeated assessment of cognition during development where expected maturational changes in cognition must be accounted for during cognitive testing.

Detecting cognitive impairment after concussion: sensitivity of change from baseline and normative data methods using the CogSport/Axon cognitive test battery.

Concussion-related cognitive impairments are typically evaluated with repeated neuropsychological assessments where post-injury performances are compared with pre-injury baseline data (baseline method). Many cases of concussions, however, are evaluated in the absence of baseline data by comparing post-injury performances with normative data (normative method). This study aimed to compare the sensitivity and specificity of these two methods using the CogSport/Axon test battery. Normative data and reliable change indices were computed from a non-injured athlete sample (n = 235). Test-retest data from non-injured (n = 260) and recently concussed (n = 29) athlete samples were then used to compare the two methods. The baseline method was found to be more sensitive than the normative method, and both methods had high specificity and overall correct classification rates. This suggests that while the normative method identifies most cases of recent concussions, the baseline method remains a more precise approach to assessing concussion-related cognitive impairments.