Post-traumatic stress disorder symptom remission and cognition in a large cohort of civilian women.

BACKGROUND: Post-traumatic stress disorder (PTSD) is associated with cognitive impairments. It is unclear whether problems persist after PTSD symptoms remit. METHODS: Data came from 12 270 trauma-exposed women in the Nurses' Health Study II. Trauma and PTSD symptoms were assessed using validated scales to determine PTSD status as of 2008 (trauma/no PTSD, remitted PTSD, unresolved PTSD) and symptom severity (lifetime and past-month). Starting in 2014, cognitive function was assessed using the Cogstate Brief Battery every 6 or 12 months for up to 24 months. PTSD associations with baseline cognition and longitudinal cognitive changes were estimated by covariate-adjusted linear regression and linear mixed-effects models, respectively. RESULTS: Compared to women with trauma/no PTSD, women with remitted PTSD symptoms had a similar cognitive function at baseline, while women with unresolved PTSD symptoms had worse psychomotor speed/attention and learning/working memory. In women with unresolved PTSD symptoms, past-month PTSD symptom severity was inversely associated with baseline cognition. Over follow-up, both women with remitted and unresolved PTSD symptoms in 2008, especially those with high levels of symptoms, had a faster decline in learning/working memory than women with trauma/no PTSD. In women with remitted PTSD symptoms, higher lifetime PTSD symptom severity was associated with a faster decline in learning/working memory. Results were robust to the adjustment for sociodemographic, biobehavioral, and health factors and were partially attenuated when adjusted for depression. CONCLUSION: Unresolved but not remitted PTSD was associated with worse cognitive function assessed six years later. Accelerated cognitive decline was observed among women with either unresolved or remitted PTSD symptoms.

Sensitivity of Individual and Composite Test Scores from the Cogstate Brief Battery to Mild Cognitive Impairment and Dementia Due to Alzheimer's Disease.

BACKGROUND: The Cogstate Brief Battery (CBB) is a computerized cognitive test battery used commonly to identify cognitive deficits related to Alzheimer's disease (AD). However, AD and normative samples used to understand the sensitivity of the CBB to AD in the clinic have been limited, as have the outcome measures studied. OBJECTIVE: This study investigated the sensitivity of CBB outcomes, including potential composite scores, to cognitive impairment in mild cognitive impairment (MCI) and dementia due to AD, in carefully selected samples. METHODS: Samples consisted of 4,871 cognitively unimpaired adults and 184 adults who met clinical criteria for MCI (Clinical Dementia Rating (CDR) = 0.5) or dementia (CDR > 0.5) due to AD and CBB naive. Speed and accuracy measures from each test were examined, and theoretically- and statistically-derived composites were created. Sensitivity and specificity of classification of cognitive impairment were compared between outcomes. RESULTS: Individual CBB measures of learning and working memory showed high discriminability for AD-related cognitive impairment for CDR 0.5 (AUCs ∼ 0.79-0.88), and CDR > 0.5 (AUCs ∼ 0.89-0.96) groups. Discrimination ability for theoretically derived CBB composite measures was high, particularly for the Learning and Working Memory (LWM) composite (CDR 0.5 AUC = 0.90, CDR > 0.5 AUC = 0.97). As expected, statistically optimized linear composite measures showed strong discrimination abilities albeit similar to the LWM composite. CONCLUSIONS: In older adults, the CBB is effective for discriminating cognitive impairment due to MCI or AD-dementia from unimpaired cognition with the LWM composite providing the strongest sensitivity.

Associations between Participant Characteristics and Participant Feedback about an Unsupervised Online Cognitive Assessment in a Research Registry.

BACKGROUND: This study aims to understand whether and how participant characteristics (age, gender, education, ethnocultural identity) are related to their feedback about taking a remote, unsupervised, online cognitive assessment. METHODS: The Brain Health Registry is a public online registry which includes cognitive assessments. Multivariable ordinal regressions assessed associations between participant characteristics and feedback responses of older (55+) participants (N=11,553) regarding their Cogstate Brief Battery assessment experience. RESULTS: Higher age, secondary education or less, Latino identity, and female gender were associated with a poorer assessment experience; higher age and a non-White identity were associated with experiencing the assessment instructions as less clear; and higher age, non-White identity, and secondary education or less were associated with rating additional human support with the assessment as more useful. DISCUSSION: Our findings highlight the importance of improving the design and instructions of unsupervised, remote, online cognitive assessments to better suit the needs of diverse communities.

A comparison of clinical assessment with common diagnostic tools for monitoring concussion recovery in adolescent rugby union players.

OBJECTIVES: To characterise the incidence, severity and recovery of sport-related concussion (SRC) in schoolboy rugby players and explore whether the Sports Concussion Assessment Tool (SCAT), Cogstate Brief Battery (CBB) and the King-Devick test (K-D test) can be used to monitor concussion status through to full recovery. DESIGN: Prospective cohort study. SETTING: Rugby union has a high rate of SRC; however, there is little research investigating how concussion affects adolescent rugby players. PARTICIPANTS: Schoolboy rugby players. MAIN OUTCOME MEASURES: Participants completed baseline tests in the preseason. Participants diagnosed with SRC during the season attended for post-concussion testing on a weekly basis until recovered. RESULTS: 135 schoolboy rugby players (16.7 ± 0.82y) participated in the study. There were 18 SRCs in 16 participants. Concussion incidence was 9/1000 player hours. CBB and K-D tests were poorly associated with clinical assessment and produced high false negative rates (0.58 and 0.52 respectively). CONCLUSIONS: This study reports a relatively high match SRC incidence for an adolescent population. Analysis of clinical recovery with CBB and K-D test revealed a relatively poor ability to accurately monitor concussion status compared to clinical assessment suggesting that these tools should not be used in isolation for monitoring SRC recovery in adolescents.

Moving intra-individual variability (IIV) towards clinical utility: IIV measured using a commercial testing platform.

OBJECTIVES: Intra-individual variability (IIV), measured across repeated response times (RT) during continuous psychomotor tasks, is an early marker of cognitive change in the context of neurodegeneration. To advance IIV towards broader application in clinical research, we evaluated IIV from a commercial cognitive testing platform and compared it to the calculation approaches used in experimental cognitive studies. METHODS: Cognitive assessment was administered in participants with multiple sclerosis (MS) during the baseline of an unrelated study. Cogstate was used for computer-based measures providing three timed-trial tasks measuring simple (Detection; DET) and choice (Identification; IDN) RT and working memory (One-Back; ONB). IIV for each task was automatically output by the program (calculated as a log10-transformed standard deviation or "LSD"). We calculated IIV from the raw RTs using coefficient of variation (CoV), regression-based, and ex-Gaussian methods. The IIV from each calculation was then compared by rank across participants. RESULTS: A total of n = 120 participants with MS aged 20-72 (Mean ± SD, 48.99 ± 12.09) completed the baseline cognitive measures. For each task, the interclass correlation coefficient was generated. Each ICC showed that LSD, CoV, ex-Gaussian, and regression methods clustered strongly (Average ICC for DET: 0.95 with 95% CI [0.93, 0.96]; Average ICC for IDN: 0.92 with 95% CI [0.88 to 0.93]; Average ICC for ONB: 0.93 with 95% CI [0.90 to 0.94]). Correlational analyses indicated the strongest correlation between LSD and CoV for all tasks (rs ≥ 0.94). CONCLUSION: The LSD was consistent with research-based methods for IIV calculations. These findings support the use of LSD for the future measurement of IIV for clinical studies.

Utility of Diffusion Modeling of Cogstate Brief Battery Test Performance in Detecting Mild Cognitive Impairment.

Cognitive testing data are essential to the diagnosis of mild cognitive impairment (MCI), and computerized cognitive testing, such as the Cogstate Brief Battery, has proven helpful in efficiently identifying harbingers of dementia. This study provides a side-by-side comparison of traditional Cogstate outcomes and diffusion modeling of these outcomes in predicting MCI diagnosis. Participants included 257 older adults (160 = normal cognition; 97 = MCI). Results showed that both traditional Cogstate and diffusion modeling analyses predicted MCI diagnosis with acceptable accuracy. Cogstate measures of recognition learning and working memory accuracy and diffusion modeling variable of decision-making efficiency (drift rate) and nondecisional time were most predictive of MCI. While participants with normal cognition demonstrated a change in response caution (boundary separation) when transitioning tasks, participants with MCI did not evidence this change.

A new look at cognitive functioning in pediatric MS.

OBJECTIVE: Cognitive involvement in pediatric multiple sclerosis (MS) relative to adult MS is less defined. This study advances our understanding by measuring cognitive performances in pediatric MS, adult MS, and pediatric healthy controls. METHODS: Consecutive relapsing pediatric MS participants from the United States Network of Pediatric MS Centers were compared with pediatric healthy controls and adults with relapsing MS. Participants were compared on two screening batteries: the Brief International Cognitive Assessment for MS and the Cogstate Brief Battery. Results were transformed to age-normative z scores. RESULTS: The pediatric groups (MS vs. Healthy Controls) did not differ on either battery's composite mean score or individual test scores (ps > 0.32), nor in the proportions impaired on either battery, Brief International Cognitive Assessment for MS (26% vs. 24%, p = 0.83); Cogstate Brief Battery (26% vs. 32%, p = 0.41). The pediatric versus adult MS group even after controlling for differences in disease duration performed better on the Brief International Cognition Assessment for MS composite (p = 0.03), Symbol Digit Modalities Test (p = 0.02), Rey Auditory Verbal Learning Test (p = 0.01), and Cogstate choice reaction time (p < 0.001). CONCLUSION: Pediatric MS patients do not differ from healthy pediatric controls on cognitive screens but perform better than adults with MS.

The effect of opioid-sparing anesthesia regimen on short-term cognitive function after thoracoscopic surgery: a prospective cohort study.

BACKGROUND: As type of surgery and opioids are suggested risk factors for the development of cognitive decline after surgery, we evaluated the effect of an opioid-sparing anesthesia regimen involving preoperative erector spinae block and continuous infusion of flurbiprofen on the incidence of cognitive decline after video-assisted thoracoscopic surgery. METHODS: In this observational study, patients over 18 years old presenting for elective video-assisted thoracoscopic surgery were divided into two groups, the erector spinae plane block group (ESPB group, who received preoperative single shot of bi-level ESPB at T4 and T6 levels) and the control group who received intercostal nerve blocks through T5 to T7 intercostal spaces along mid-axillary line after surgery. Continuous infusion of flurbiprofen (8 mg/h) and intravenous oxycodone rescue (1 mg/bolus, lockout time 10 minutes) were provided as postoperative analgesics. Cognitive function was measured one day before and 48 h after surgery with brief Cogstate computerized battery (CCB). RESULTS: There were 60 patients included with 30 in each group. Perioperative sufentanil dose was significantly reduced in ESPB group. Nine (30%) and 15 (50%) patients had delayed neurocognitive recovery in the ESPB group and the control group respectively. Psychomotor speed and visual attention tests were the two tests that patients showed cognitive decline. The results of multivariate regression revealed that patients who were more than 53.5 years of age (OR 9.213, 95% CI 1.789, 47.437, P = 0.008) and low levels of education (less than 9 years of complimentary education) (OR 6.829, 95% CI 1.068, 43.677, P = 0.042) were independent risk factors for postoperative delayed neurocognitive recovery. For subgroup analysis, ESPB could reduce the occurrence of delayed neurocognitive recovery in patients with both risk factors (6/10 (60%) vs. 11/11 (100%), P = 0.004) compared to the control group. CONCLUSIONS: Middle-aged people and low levels of education are independent risk factors for delayed neurocognitive recovery after thoracoscopic surgery. ESPB has the potential to prevent cognitive decline in high-risk patients. TRIAL REGISTRATION: ChiCTR1800014508 ( www.chictr.org.cn , January 17, 2018; Hong Zhao, M.D.). URL: http://www.chictr.org.cn/showproj.aspx?proj=24778 . The date of the enrolment of the first participant to the trial was January 22, 2018.

A phase 1b/2a multicenter study of the safety and preliminary pharmacodynamic effects of selective muscarinic M1 receptor agonist HTL0018318 in patients with mild-to-moderate Alzheimer's disease.

INTRODUCTION: This study examined the safety and pharmacodynamic effects of selective muscarinic M1 receptor orthosteric agonist HTL0018318 in 60 patients with mild-to-moderate Alzheimer's disease (AD) on background donepezil 10 mg/day. METHODS: A randomized, double-blind, placebo-controlled 4-week safety study of HTL0018318 with up-titration and maintenance phases, observing exploratory effects on electrophysiological biomarkers and cognition. RESULTS: Treatment-emergent adverse events (TEAEs) were mild and less frequently reported during maintenance versus titration. Headache was most commonly reported (7-21%); 0 to 13% reported cholinergic TEAEs (abdominal pain, diarrhea, fatigue, nausea) and two patients discontinued due to TEAEs. At 1 to 2 hours post-dose, HTL0018318-related mean maximum elevations in systolic and diastolic blood pressure of 5 to 10 mmHg above placebo were observed during up-titration but not maintenance. Postive effects of HTL0018318 were found on specific attention and memory endpoints. DISCUSSION: HTL0018318 was well tolerated in mild-to-moderate AD patients and showed positive effects on attention and episodic memory on top of therapeutic doses of donepezil.

Longitudinal Cognitive Decline in Patients With Mild Cognitive Impairment or Dementia Due to Alzheimer's Disease.

Sensitive cognitive assessments accurately detect and track cognitive decline in Alzheimer's disease. The Cogstate battery was used to measure cognitive change in cognitively normal participants and in individuals with mild cognitive impairment and mild Alzheimer's disease enrolled in the Australian Imaging, Biomarker and Lifestyle Rate of Change Substudy. Over 18 months, verbal episodic memory performance declined for mild cognitive impairment and mild Alzeheimer's disease groups when compared to cognitively normal participants. Frequent assessments of episodic memory may facilitate early detection of cognitive decline due to Alzheimer's disease.

Cogstate Brief Battery: Cognition and the feigning of cognitive impairment in chronic pain.

Chronic pain (CP) is often associated with cognitive impairment. The Cogstate Brief Battery (CBB), a computerized assessment battery, has been studied in several neuropsychiatric disorders but not in CP. Since feigning of cognitive impairment is common in CP, the current study aimed to assess the CBB's utility in differentiating CP patients (n = 64) from healthy participants (n = 33), as well as to assess the effect of simulating cognitive impairment by CP patients on performance in the battery. CP outpatients were randomly assigned to one of two groups: (a) Patients performing the CBB to the best of their ability. (b) Patients simulating cognitive impairment. Independent-samples t-tests indicated that three of four CBB tasks successfully differentiated CP patients from matched healthy controls. Additionally, an analysis of covariance (ANCOVA) indicated that CP patients who simulated cognitive impairment performed more poorly in all four CBB tasks, with the detection task having the strongest discrimination capacity. This is the first study to point toward the usefulness and sensitivity of the CBB for assessment of cognition and detection of feigned cognitive impairment in CP. Further studies are required to validate these preliminary findings and assess the CBB's utility in daily clinical practice.

The association of posttraumatic stress disorder, depression, and head injury with mid-life cognitive function in civilian women.

BACKGROUND: Despite evidence linking posttraumatic stress disorder (PTSD), depression, and head injury, separately, with worse cognitive performance, investigations of their combined effects on cognition are limited in civilian women. METHODS: The Cogstate Brief Battery assessment was administered in 10,681 women from the Nurses' Health Study II cohort, mean age 64.9 years (SD = 4.6). Psychological trauma, PTSD, depression, and head injury were assessed using online questionnaires. In this cross-sectional analysis, we used linear regression models to estimate mean differences in cognition by PTSD/depression status and stratified by history of head injury. RESULTS: History of head injury was prevalent (36%), and significantly more prevalent among women with PTSD and depression (57% of women with PTSD and depression, 21% of women with no psychological trauma or depression). Compared to having no psychological trauma or depression, having combined PTSD and depression was associated with worse performance on psychomotor speed/attention ( ß = -.15, p = .001) and learning/working memory ( ß = -.15, p < .001). The joint association of PTSD and depression on worse cognitive function was strongest among women with past head injury, particularly among those with multiple head injuries. CONCLUSIONS: Head injury, like PTSD and depression, was highly prevalent in this sample of civilian women. In combination, these factors were associated with poorer performance on cognitive tasks, a possible marker of future cognitive health. Head injury should be further explored in future studies of PTSD, depression and cognition in women.

Outcomes from the use of computerized neurocognitive testing in a recurrent glioblastoma clinical trial.

Assessment of neurocognitive function (NCF) is important in brain tumor clinical trials, however there are varying methodologies available. We used the Cogstate computerized NCF testing battery and the mini-mental state examination (MMSE) to prospectively assess cognition in adult patients with recurrent glioblastoma (GBM) enrolled in the CABARET randomized phase II clinical trial of bevacizumab versus bevacizumab plus carboplatin chemotherapy. We determined completion rates; compared NCF results between trial arms; and assessed baseline NCF as a predictor of survival outcome. 93 of 103 eligible patients completed baseline Cogstate NCF testing. Completion rates were between 60 and 100% across each timepoint, and 38% at disease progression. There was no evidence of difference between arms in time to deterioration in NCF using either test. Prior to disease progression, deterioration on the Cogstate tests was substantially more common (90%) than deterioration on the MMSE (37%), and decline in the Cogstate composite score within the first 8 weeks was associated with shorter overall survival. This testing methodology may be useful when determining net clinical benefit for therapies in patients with recurrent GBM.

Variable objective sleep quality is related to worse spatial learning and memory in young adults.

OBJECTIVE: The majority of research on sleep and cognition has focused on mean markers of sleep across multiple nights; however, variable sleep patterns have become increasingly common in the modern era. The purpose of this study was to examine whether objective intraindividual variability in sleep quantity and quality are related to verbal and visuospatial learning and memory functioning in young adults. METHODS: A total of 218 young adult college students were recruited from a university in the Eastern United States, among which 187 participants (70.6% female; mean age = 20.5, SD = 1.5) had complete actigraphy and cognitive performance data. Objective intraindividual means and variabilities of sleep quantity (total sleep time) and sleep quality (percent wake after sleep onset) were measured over a 1- to 2-week timeframe using wrist actigraphy. Verbal and visuospatial learning and memory were assessed using the International Shopping List and Groton Maze Learning tests of the Cogstate computerized test battery. RESULTS: Greater intraindividual variability in actigraphy-derived sleep quality was associated with poorer visuospatial learning and memory performance after controlling for mean sleep quality and visuomotor attention and processing speed (ps < 0.05). Actigraphic measures of sleep quantity were not related to any learning and memory measures. CONCLUSION: In young adults, intraindividual variability in objective sleep quality was significantly related to visuospatial learning and memory, over and above mean sleep quality. Given these associations, future studies should aim to identify modifiable lifestyle and environmental factors contributing to variable sleep quality.

An examination of reliable change methods for measuring cognitive change with the Cogstate Computerized Battery: Research and clinical implications.

OBJECTIVE: To compare the performance of four reliable change (RC) methods with respect to measuring cognitive change on the Cogstate Computerized Battery (CCB). METHOD: We assessed cognitive change in 57 healthy, urban, well-educated males on the CCB at baseline and 6 months (Median age = 50, 65% university-educated). The study CCB version comprised seven measures covering attention, processing speed, verbal learning, and memory. Raw scores were z-score transformed using age-corrected Cogstate norms (CN) or the sample mean and standard deviation (internal standardization [IS]), and then averaged to create composite z-scores. Composite scores were entered into four RC formulae. RC was defined based on a 90% two-tailed confidence interval. Change scores were compared as continuous (z-scores) and ordinal variables (RC outcomes). RESULTS: CCB composite score reliability (rXY = .78-.79) was replicated in an age- and sex-matched Cogstate database sample of similar size. There was good overall agreement between the four RC methods (Bland-Altman Mdiff = .00; 95% limits of agreement with the mean-CN: z = ± .90; IS: z = ± .93), with each model adhering closely to the 10% rate of RC expected by chance alone (largest χ2 = .86, p = .99). Initial norming strategy (CN or IS) did not affect these outcomes. CONCLUSIONS: Norming strategy and RC method choice did not significantly impact cognitive change predictions on CCB composite scores. A series of example case data are provided to practically demonstrate the steps involved in applying the longitudinal norms generated in this study. Research in more diverse normative samples is warranted.

Correlation between computerised and standard cognitive testing in people with HIV and HIV-negative individuals.

We investigated the correlations and agreement between cognitive assessments made using a computerised (CogState™, six domains) and a standard pen-and-paper battery (five domains) in PWH and lifestyle-similar HIV-negative individuals. Demographically adjusted domain and global T-scores were obtained and used to define cognitive impairment according to the multivariate normative comparison (MNC) criteria. Correlations between T-scores and the agreement between the classifications of cognitive impairment obtained from the two batteries were assessed using the Spearman's rank correlation and Cohen's κ, respectively. The correlation between global T-scores from the two batteries was 0.52 (95% CI 0.44-0.60) in PWH and 0.45 (0.29-0.59) in controls (p = 0.38 for their difference). Correlations were generally stronger between domains within the same battery than between those from different batteries. The agreement between the two batteries in classifying individuals as cognitively impaired or not impaired was fair in PWH (κ = 0.24) and poor in HIV-negative individuals (κ = -0.02). The moderate correlation between overall cognitive function and the modest agreement between binary classifications of cognitive impairment obtained from two different batteries indicate the two batteries may assess slightly different components of cognition.

Preliminary exploration of a computerized cognitive battery and comparison with traditional testing in patients with high-grade glioma.

BACKGROUND: Cognitive function is an important outcome measure in many brain tumor clinical trials, and investigators are interested in employing the most efficient methods of cognitive assessment for this purpose. Computerized testing can be appealing because of the perceived ease of use and electronic data generated. Traditional tests may have the advantage of accumulated validity evidence and comparability across historic trials. METHODS: We evaluated feasibility of a Cogstate battery in 39 patients with high-grade glioma, and compared it with a commonly used paper-and-pencil battery. RESULTS: Both batteries were well tolerated and rated equally likeable. Correlations between the batteries were low to low-moderate. More patients showed impairment at baseline and decline across trials on traditional tests. CONCLUSIONS: Both batteries were well tolerated, but the most complicated tasks (from both batteries) could not be completed by all subjects. Preliminary validity evidence for the Cogstate tasks was mixed, but a larger sample is needed.

Efficacy of Cognition Support Formula® on cognitive function in older adults with subjective cognitive impairment: a protocol for a 26-week, randomised, double-blind, placebo-controlled trial.

BACKGROUND: Due to an ageing population in Australia there has been an increase in the number of older adults with subjective cognitive impairment (SCI), a self-reported decline in cognitive function associated with an increased risk of mild cognitive impairment and dementia. There is no current, recommended treatment for SCI; therefore, the effectiveness of a supplement approved by the Therapeutic Goods Association that has the potential to enhance cognitive function in an at-risk cohort should be tested. The primary aim of this proposed research is to determine the efficacy of 6 months of treatment with BioCeuticals Cognition Support Formula® (containing Bacopa monniera (brahmi), Ginkgo biloba, Panax ginseng and alpha-lipoic acid) on cognition in older adults with SCI (utilising the CogState® one card learning and identification tests as co-primary outcome measures of visual short-term memory and attention; mean speed (ms), accuracy (%), and total number of hits, misses, and anticipations) compared with placebo. The secondary aims are to assess an improvement in other cognitive domains (executive functioning, processing speed, and working memory), evaluate safety, adverse effects, and determine efficacy on mood, fatigue, and neurocognition. It is expected that improvements across the study timepoints in the co-primary outcomes in the active treatment group (compared with placebo) will be evident. METHOD: One-hundred and twenty participants will be recruited for the randomised, double-blind, placebo-controlled study. Participants will be randomly assigned to one of the treatment groups (active or placebo) at a 1:1 ratio, and will be required to complete a series of cognitive (using CogState®), mood (using the Depression, Anxiety, Stress Scale (DASS-42) and Short Health Anxiety Inventory (SHAI)), and fatigue (using the Functional Assessment of Chronic Illness Therapy Fatigue Scale (FACIT-F)) tasks at baseline (0 months), the midpoint (3 months), and the endpoint (6 months). These tasks will be evaluated between timepoints (baseline vs. midpoint, midpoint vs. endpoint, and baseline vs. endpoint). Neurocognition will be measured by electroencephalography at baseline and at the endpoint in half of the participants. Adverse effects will be documented over the 6-month trial period. DISCUSSION: This is the first study to test the efficacy of Cognition Support Formula® on cognition in older adults with SCI. As people with SCI have an increased risk of dementia, and there are limited treatments options for this population, it is important to assess a supplement that has the potential to enhance cognitive function. TRIAL REGISTRATION: Universal Trial Number (UTN), U1111-1196-9548. Australian New Zealand Clinical Trials Registry, ACTRN12617000945325 . Registered on 30 June 2017.

Explaining Upper or Lower Extremity Crossover Effects of Visuomotor Choice Reaction Time Training.

Current evidence indicates a strong relation between improved visuomotor choice reaction time (VMRT) and a reduced risk of lower extremity injury, making both lower- and upper extremity VMRT training paradigms valuable to athletes. This investigation studied as yet unconfirmed crossover effects of upper extremity training on lower extremity performance; and we evaluated underlying relevant perceptual and cognitive adaptations. In this three-armed, randomized, controlled intervention, we used a computerized training device to compare participants receiving four weeks of upper (n = 12) and lower (n = 12) extremity VMRT training with a control group (n = 13) of healthy participants. Collectively, our participants had a mean age of 24.6 years (SD = 2.2), a mean height of 173 cm (SD = 10), and a mean weight of 69.6 kg (SD = 12.1); 57% (n = 21) were female and 43% (n = 16) were male. We assessed participants' upper and lower extremity VMRT performance and domain-specific perceptual and cognitive abilities before and after intervention and analyzed differences between their before and after performances. Lower extremity training enhanced VMRT performances for both lower extremity and crossover upper extremity. Upper extremity training improved VMRT for upper extremity and increased cognitive choice reaction performance but yielded no crossover effects to lower extremity. We found no effects of VMRT training on other domain-specific cognitive performance markers (attention, executive function, memory, or working memory). VMRT training modulated only task-specific cognitive performance and induced crossover effects from lower extremity training to upper extremity performance but not vice versa.

Computerized assessment of cognitive impairment among children undergoing radiation therapy for medulloblastoma.

PURPOSE: Advantages to computerized cognitive assessment include increased precision of response time measurement and greater availability of alternate forms. Cogstate is a computerized cognitive battery developed to monitor attention, memory, and processing speed. Although the literature suggests the domains assessed by Cogstate are areas of deficit in children undergoing treatment for medulloblastoma, the validity of Cogstate in this population has not been previously investigated. METHODS: Children participating in an ongoing prospective trial of risk-adapted therapy for newly diagnosed medulloblastoma (n = 73; mean age at baseline = 12.1 years) were administered Cogstate at baseline (after surgery, prior to adjuvant therapy) and 3 months later (6 weeks after completion of radiation therapy). Gold-standard neuropsychological measures of similar functions were administered at baseline. RESULTS: Linear mixed models revealed performance within age expectations at baseline across Cogstate tasks. Following radiation therapy, there was a decline in performance on Cogstate measures of reaction time (Identification and One Back). Females exhibited slower reaction time on One Back and Detection tasks at baseline. Higher-dose radiation therapy and younger age were associated with greater declines in performance. Pearson correlations revealed small-to-moderate correlations between Cogstate reaction time and working memory tasks with well-validated neuropsychological measures. CONCLUSIONS: Cogstate is sensitive to acute cognitive effects experienced by some children with medulloblastoma and demonstrates associations with clinical predictors established in the literature. Correlations with neuropsychological measures of similar constructs offer additional evidence of validity. The findings provide support for the utility of Cogstate in monitoring acute cognitive effects in pediatric cancer.