| Title: |
Immediate neuropsychological and behavioral benefits of computerized cognitive rehabilitation in Ugandan pediatric cerebral malaria survivors |
| Author(s): |
Bangirana, Giordani, John, Page, Opoka & Boivin |
| Year: |
2009 |
| Presented at/ Published In: |
J Dev Behav Pediatr, 30(4): 310–318. |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| Objective— Our earlier studies on Ugandan children surviving cerebral malaria showed cognitive deficits mainly in attention and memory. We now present the first study in sub-Saharan Africa to investigate the feasibility and potential benefits of computerized cognitive rehabilitation training on neuropsychological and behavioural functioning of children surviving cerebral malaria.
Methods—A randomized trial in which 65 children admitted 45 months earlier with cerebral malaria were recruited at Mulago Hospital, Kampala, Uganda. For eight weeks, 32 of the children received weekly training sessions using Captain’s Log cognitive training software and the other 33 were assigned to a non treatment condition. Pre- and post-intervention assessments were completed using CogState, a computerized neuropsychological battery, measuring Visuomotor Processing
Speed, Working Memory, Learning, Attention and Psychomotor Speed and the Child Behavior Checklist measuring Internalising Problems, Externalising Problems and Total Problems.
Results—Pre-intervention scores were similar between both groups. Treatment effects were observed on Visual Spatial Processing Speed (group effect (standard error) 0.14 (0.03); p< 0.001); on a Working Memory and Learning task (0.08 (0.02); p< 0.001), Psychomotor Speed (0.14 (0.07); p= 0.04) and on Internalising Problems (-3.80 (1.56); p= 0.02) after controlling for age, sex, school grade, quality of the home environment and weight for age z scores. Similar treatment effects were observed when no adjustments for the above covariates were made.
Conclusions— Computerized cognitive training long after the cerebral malaria episode has immediate benefit on some neuropsychological and behavioral functions in African children. The long-term benefit of this intervention needs to be investigated. |
 |
|
| Title: |
Hippocampal region-specific contributions to memory performance in normal elderly |
| Author(s): |
Chen, Chuah, Sim & Chee |
| Year: |
2010 |
| Presented at/ Published In: |
Brain and Cognition, 72, 400–407 |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| To investigate the relationship between regional hippocampal volume and memory in healthy elderly, 147 community-based volunteers, aged 55–83 years, were evaluated using magnetic resonance imaging, the Groton Maze Learning Test, Visual Reproduction and the Rey Auditory Verbal Learning Test. Hippocampal volumes were determined by interactive volumetry. We found greater age-related reduction in the volume of the hippocampal head relative to the tail. Right hippocampal tail volume correlated with spatial memory on the Groton Maze Learning Test while left hippocampal body volume was associated with delayed verbal memory. These associations were independent of age, sex, education and speed of processing and support the notion of functional differentiation along the long axis of the hippocampus. |
|
|
| Title: |
Sleep following sport-related concussions |
| Author(s): |
Gosselin, Lassonde, Petit, Leclerc, Mongrain, Collie & Montplaisir |
| Year: |
2009 |
| Presented at/ Published In: |
Sleep Medicine, 10, 35-46 |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| Objectives: Sleep and vigilance disorders are among the most commonly reported symptoms following a concussion. The aim of the study was thus to investigate the effects of sport-related concussions on subjective and objective sleep quality. Methods: Ten concussed athletes and 11 non-concussed athletes were included. Concussed athletes had a history of 4.6 ± 2.1 concussions with at least one concussion during the last year. They were recorded for two consecutive nights in the laboratory and during a 10-min period of wakefulness. They completed questionnaires related to sleep quality and symptoms as well as neuropsychological tests and the CogSport computer battery. Results: Concussed athletes reported more symptoms and worse sleep quality than control athletes, but no between-group differences were found on polysomnographic variables or on REM and NREM sleep quantitative EEG variables. However, concussed athletes showed significantly more delta activity and less alpha activity during wakefulness than did control athletes. Conclusion: In spite of the subjective complaints in sleep quality of concussed athletes, no change was observed in objective sleep characteristics. However, concussions were associated with an increase in delta and a reduction in alpha power in the waking EEG. Sport-related concussions are thus associated with wakefulness problems rather than sleep disturbances. |
|
|
| Title: |
Assessment of cognition in an adolescent Indigenous population |
| Author(s): |
Lewis, Dingwall, Berkhout, Sayers, Maruff & Cairney |
| Year: |
2010 |
| Presented at/ Published In: |
Australian Psychologist, June 2010; 45(2): 123–131 |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| The assessment of cognition in Indigenous populations is often complicated by cultural and language differences and unfamiliarity with the assessment process. Cognitive tasks are being developed that reduce the impact of these factors. These processes need to be evaluated in different cultural and ethnic groups to determine whether they are appropriate. Such an assessment was recently used in two studies of cognition of 237 Indigenous Australian adolescents (age: M¼16.06+2.16 years). The tasks were completed appropriately, with response times and error rates increasing for difficult tasks. Duration and error rates decreased for the round-based tasks, in line with performance in non-Indigenous samples. There were no gender effects. Age associations occurred in some tasks, but significant correlations were only of a small magnitude. Although the battery appeared to be completed appropriately in this study, more work needs to be conducted examining the influence of demographic factors to ensure that control data can be most appropriately matched in future studies. |
|
|
| Title: |
Neuropsychological profiles of young people with type 1 diabetes 12 yr after disease onset |
| Author(s): |
Lin, Northam, Rankins, Werther & Cameron |
| Year: |
2010 |
| Presented at/ Published In: |
Pediatric Diabetes 2010 |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| Background: Lowered neuropsychological performance is evident in youth with type 1 diabetes, although evidence for associations with specific illness variables is inconsistent. This study examined the neuropsychological profiles of a cohort of youth with type 1 diabetes studied prospectively from diagnosis 12 yr previously. Methods: A total of 106 youth with type 1 diabetes and 75 healthy controls participated. There were no significant group differences on Full-scale IQ assessed on study entry 12 yr previously, current socioeconomic status, gender distribution, or age. Neuropsychological tests assessed eight cognitive domains: verbal abilities, perceptual reasoning, new learning, working memory, non-verbal processing speed, mental efficiency, divided attention, and sustained attention. Episodes of serious hypoglycemia and HbA1c levels were recorded from diagnosis. Results: Youth with type 1 diabetes performed more poorly than controls on working memory (p < .05). Early onset diabetes was related to poorer sustained (p < .001) and divided attention (p = .001), new learning, and mental efficiency (both p < .05). Hypoglycemia was found to adversely effect verbal abilities, working memory, and non-verbal processing speed (all p < .05). Poorer working memory was associated with hyperglycemia (p < .05). Youth with any combination of two or three illness risk factors (i.e., early onset diabetes, hypo-, hyperglycemia), performed more poorly than controls and youth with no or one risk on verbal abilities, working memory, and mental efficiency. Conclusions: This study documents poorer neuropsychological performance and its association with illness risk factors in youth with type 1 diabetes. Findings suggest that early disease onset and hypoglycaemia impact on the developing central nervous system, with hyperglycemia playing a lesser role. |
|
|
| Title: |
Slower Reaction Times and Impaired Learning in Young Adults with Birth Weight _1500 g |
| Author(s): |
Strang-Karlsson, Andersson, Paile-Hyvärinen, Darby, Hovi, Räikkönen, Pesonen, Heinonen, Järvenpää, Eriksson & Kajantie |
| Year: |
2010 |
| Presented at/ Published In: |
Pediatrics 2010 |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| Objective: Children with very low birth weight (VLBW; _1500 g) perform worse on cognitive tests than do children who are born at term. Whether this difference persists into adulthood has been little studied. We assessed core neurocognitive abilities (processing speed, working memory, attention, and learning capacity) in young adults with VLBW and in term-born control subjects. Methods: In conjunction with the Helsinki Study of Very Low Birth Weight Adults, 147 VLBW and 171 control subjects who were aged 18 to 27 years and did not have neurosensory impairments performed a computerized test battery (CogState Ltd, Melbourne, Australia). T tests and linear regression models were used. Cohen’s d was used to express effect size (ES). Results: VLBW adults had slower reaction times than did control subjects on all 5 tasks: simple reaction time (mean difference: 4.0% [95% confidence interval (CI): 1.1%–7.0%]; ES: 0.30), choice reaction time
(mean difference: 3.2% [95% CI: 0.3%– 6.2%]; ES: 0.24), working memory (mean difference: 8.4% [95% CI: 3.7%–13.4%]; ES: 0.40), divided attention (mean difference: 7.2% [95% CI: 2.7%–11.9%]; ES: 0.36), and associated learning reaction time (mean difference: 6.4% [95% CI: 1.3%–11.9%]; ES: 0.28). In addition, VLBW adults showed impaired learning abilities on the associated learning task (percentage of correct responses: 85.7 vs 80.2; P _ .001; ES: 0.64). The results were little affected by adjustment for confounders. Conclusions: Nonimpaired VLBW individuals exhibited slower psychomotor speed and lower accuracy on the associated learning task. These results indicate that very preterm birth, even when obvious neurosensory deficits are absent, may have long-term consequences on core neurocognitive abilities.
|
|
|
| Title: |
Memory decline in healthy older people |
| Author(s): |
Collie, Maruff, Shafiq-Antonacci, Smith, Hallup, Schofield, Masters and Currie |
| Year: |
2001 |
| Presented at/ Published In: |
Neurology |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| Background: Criteria for mild cognitive impairment require objective evidence of a memory deficit but do not require objective evidence of memory decline. Application of these criteria may therefore result in the misclassification of older patients with memory decline as normal because their neuropsychological test performance at a single point in time may be within normal limits. This study aimed to identify and characterize older people with memory decline. Method: Word list delayed recall (WLDR) test performance was assessed on five occasions during a 2-year period in a cohort of healthy older individuals. Older people with declining (n 5 35) and nondeclining (n 5 66) WLDR scores were identified. Both subgroups were then compared on apoE genotype, Clinical Dementia Rating, and neuropsychological test performance at the fifth assessment. Results: Thirty-four percent of the group with declining memory recorded a Clinical Dementia Rating of 0.5, compared with 5% of the nondeclining memory group. No between-group differences were observed in cognitive domains other than memory, self-reported cognitive failures, or the proportion of each group carrying the apoE epsilon 4 allele. Conclusions: A large proportion of healthy older individuals show memory decline, which may represent the early stages of a potentially more severe cognitive impairment. Further investigation is necessary to determine the relationship between apoE genotype, self-reported cognitive impairment, and memory decline in older people. |
|
|
| Title: |
Statistical procedures for determining the extent of cognitive change following concussion |
| Author(s): |
Collie, Maruff, Makdissi, McStephen, Darby, McCrory |
| Year: |
2004 |
| Presented at/ Published In: |
British Journal of Sports Medicine |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| Neuropsychological (NP) testing is now often used to help to determine if the cognitive function of a concussed athlete has declined. The NP test score after concussion is compared with the baseline test score. Many clinicians simply subtract one from the other and make a clinical decision about the significance or otherwise of the resulting ‘‘difference score’’. Such techniques are inadequate, as they fail to account for the many factors that may confound interpretation of serially acquired cognitive test scores. This is a review of a number of alternative approaches used in other areas of medicine for differentiating ‘‘true’’ changes from changes caused by these confounding factors. A case example is used to illustrate the effect that the statistical approach may have on clinical decision making. |
|
|
| Title: |
Measuring deficits in visually guided action post-concussion |
| Author(s): |
Locklin, Bunn, Roy, Danckert |
| Year: |
2010 |
| Presented at/ Published In: |
Sports Medicine |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| Recent concussion research has led to the development of computerized test batteries designed to measure working memory and psychomotor speed deficits in acute stage post-concussion. These tests lack a measure of motor control deficits, which may linger well after other symptoms have remitted. For athletes, this may mean returning to play while still uncoordinated or neurologically fragile. The present research involved the development of a visuomotor pointing task designed to induce a speed-accuracy trade off to measure motor planning and execution performance in concussed athletes. Data collected using this tool were contrasted with CogSport, a commercially available computerized test battery designed to assess residual cognitive effects of concussion in athletes. Results suggest that a motor task may be able to detect long-term effects of concussion not measurable with CogSport. If future research can confirm these findings, we suggest that a measure of motor control may need to be added to existing batteries to improve their sensitivity to long term effects. |
|
|
| Title: |
Convergent validity and effect of instruction modification on the Groton Maze Learning Test: A new measure of spatial working memory and error monitoring |
| Author(s): |
Pietrzak, Maruff, Snyder |
| Year: |
2009 |
| Presented at/ Published In: |
International Journal of Neuroscience |
| Type: |
Article |
| Status: |
Published |
| Abstract: |
| This study examined the convergent validity and effect of instruction modification on the Groton Maze Learning Test (GMLT), a computerized hidden maze learning test. Performance on the GMLT was compared to performance on widely used pencil-and-paper and computerized measures of working memory, route selection, and planning/problem solving in a sample of healthy young adults. Performance on GMLT outcome measures correlated with performance on comparator measures of working memory, route selection, and planning (r = 0.31–0.44). Instruction modification (withholding simple instructions) increased the number of rule-break errors on the GMLT (Cohen’s d = 0.59). These results provide support for the convergent validity of the GMLT in assessing working memory, route selection, and planning/problem solving, and suggest that a simple instructional modification may yield a novel measure of executive function: feedback monitoring and procedural rule acquisition and application. |
|
|
