Jane L. Mathias

Changes in attention and information-processing speed following severe traumatic brain injury: A meta-analytic review.

Deficits in attention are frequently reported following severe traumatic brain injury (TBI). However, methodological differences make it difficult to reconcile inconsistencies in the research findings in order to undertake an evidence-based assessment of attention. The current study therefore undertook a meta-analytic review of research examining attention following severe TBI. A search of the PsycINFO and PubMed databases spanning the years 1980 to 2005 was undertaken with 24 search terms. Detailed inclusion and exclusion criteria were used to screen all articles, leaving 41 studies that were included in the current meta-analysis. Weighted Cohens d effect sizes, percentage overlap statistics, and confidence intervals were calculated for the different tests of attention. Fail-safe Ns were additionally calculated to address the bias introduced by the tendency to publish significant results. Large and significant deficits were found in specific measures of information-processing speed, attention span, focused/selective attention, sustained attention, and supervisory attentional control following severe TBI. Finally, age, education, and postinjury interval were not significantly related to these deficits in attention.

Neuropsychological and information processing deficits following mild traumatic brain injury.

Neuroradiological and neuropathological investigations have found evidence of diffuse brain damage in the frontal and temporal lobes, corpus callosum, and fornices in patients who have sustained a mild traumatic brain injury (TBI). However, neuropsychological assessments of these patients do not typically target many of the subtle information processing deficits that may arise from diffuse damage involving the frontotemporal regions of the brain as well as white matter pathology, including the corpus callosum. Consequently, we have a limited understanding of the deficits that may be attributable to temporary or permanent disruptions to these functional pathways. This study assessed a group of mild TBI patients (N = 40) and a matched control group (N = 40) on a number of standard neuropsychological tests of selective and sustained attention, verbal and non-verbal fluency, and verbal memory. In addition, reaction time (RT) tasks, requiring both the inter- and intra-hemispheric processing of visual and tactile information, were used to assess the functional integrity of the tracts that are likely to be affected by diffuse damage. In the 1st month after sustaining their injury, the mild TBI group demonstrated deficits in attention, non-verbal fluency, and verbal memory. They also demonstrated slower visual and tactile RTs, with the visual RTs of mild TBI patients being more affected by increased task difficulty and the need to transfer information across the corpus callosum, than did their matched controls.

Hormone therapy, timing of initiation, and cognition in women aged older than 60 years: the REMEMBER pilot study.

Objective:The aim of this pilot study was to assess any trends related to the timing of initiation, and duration, of hormone therapy (HT) use on cognitive function to facilitate the design and power calculations for a future large cohort study entitled Research into Memory, Brain function and Estrogen Replacement (REMEMBER). Design:A total of 428 women aged older than 60 years were recruited from a computer-generated random selection of Adelaide households. Demographic and lifestyle characteristics, and HT use history were recorded and confirmed. The Center for Epidemiological Studies-Depression score was used to assess mood. Cognitive tests were administered measuring global cognition (Mini-Mental State Examination), attention and concentration (Trail Making Test Parts A and B), verbal learning and memory (Consortium to Establish a Registry for Alzheimers Disease [CERAD] word list immediate and delayed recall), and verbal expression (letter fluency [FAS], category fluency [Animals], and the Boston Naming Test [short form]). Analyses were adjusted for age, education, mood, body mass index, smoking, alcohol intake, and history of cerebrovascular disease. HT use was defined as the use of systemic HT for at least 1 year. Early initiation of HT use was defined as commencement of HT before age 56 years for women with a uterus and ovaries, or within 5 years of a hysterectomy and bilateral oophorectomy. Late initiation of HT use was defined as HT commencing after these times. Results:Early initiators of HT performed better than late initiators on the Mini-Mental State Examination (P = 0.04) and were faster than never users on the Trail Making Test Part A (P = 0.02). Women aged 70-79 years who initiated HT early performed better on the FAS test than never users (P = 0.0008). Late initiators performed worse than never users on the Mini-Mental State Examination (P = 0.09), and on the FAS test in the 60-69 year (P = 0.06) and 80 years and older (P = 0.095) age groups. However, late initiators performed better than never users on the FAS test in the 70-79 year age group (P = 0.015). HT users of less than 11 years (P = 0.09), HT users of more than 11 years (P = 0.04), and estrogen-only users (P = 0.024) performed faster than never users on the Trail Making Test Part A. Combined estrogen plus progestin users performed better than never users on the Boston Naming Test short form (P = 0.07). Conclusions:For some cognitive domains, early initiation of HT from around menopause may be beneficial, and initiation of HT in late menopause may be detrimental. The timing of the initiation of HT seems critical. To fully test these hypotheses and to further examine these trends by route and type of HT regimen in this population, a study size of 2,500 women would be required.

Neuropsychological deficits in frontotemporal dementia and Alzheimer’s disease: a meta-analytic review

We sought to identify the cognitive tests that best discriminate between Alzheimer’s disease (AD) and frontotemporal dementia (FTD). A comprehensive search of all studies examining the cognitive performance of persons diagnosed with AD and FTD, published between 1980 and 2006, was conducted. Ninety-four studies were identified, comprising 2936 AD participants and 1748 FTD participants. Weighted Cohen’s d effect sizes, percentage overlap statistics, confidence intervals and fail-safe Ns were calculated for each cognitive test that was used by two or more studies. The most discriminating cognitive tests were measures of orientation, memory, language, visuomotor function and general cognitive ability. Although there were large and significant differences between groups on these measures, there was substantial overlap in the scores of the AD and FTD groups. Age, education, years since diagnosis and diagnostic criteria did not significantly contribute to the group differences. Given the large overlap in the test performance of persons diagnosed with AD and FTD, cognitive tests should be used cautiously and in conjunction with a medical history, behavioural observations, imaging and information from relatives when making differential diagnoses.

Validity of the Montreal Cognitive Assessment (MoCA) as a Screening Test for Mild Cognitive Impairment (MCI) in a Cardiovascular Population

While rates of mild cognitive impairment (MCI) are relatively high in populations with cardiovascular diseases and risk factors, screening tests for MCI have not been evaluated in this patient group. This study investigated the sensitivity and specificity of the Montreal Cognitive Assessment (MoCA) tool for detecting MCI in 110 patients (mean age 67.9 + 11.7 years; 60% female) recruited from hospital cardiovascular outpatient clinics. Mean MoCA performance was relatively low (22.8 + 3.8) in this group, with 72.1% of participants scoring below the recommended cutoff for cognitive impairment (<26). The presence of MCI was determined using the Neuropsychological Assessment Battery Screening Module (NAB-SM). Both amnestic MCI and multiple-domain MCI were identified. The optimum MoCA cutoff for detecting MCI in this group was <24. At this cutoff, the MoCA’s sensitivity for detecting amnestic MCI was 100% and for multiple-domain MCI it was 83.3%. Specificity rates for amnestic MCI and multiple-domain MCI were 50.0% and 52% respectively. The poor specificity of the MoCA suggests that it will have limited value as a screening test for MCI in settings where the overall prevalence of MCI is low.

Performance on the Test of Everyday Attention and Standard Tests of Attention following Severe Traumatic Brain Injury

The Test of Everyday Attention (TEA) was designed to address some of the limitations of established measures of attention. However, very few studies have examined its clinical utility. A group of 35 patients who had sustained a severe TBI were compared with 35 age- and education-matched controls on the TEA, Stroop, SDMT, WMS-R Digit Span, Ruff 2s and 7s Selective Attention Test, and PASAT. Of the TEA subtests, only the Map and Telephone Search subtests of the TEA produced significant differences between the two groups, suggesting a deficit in visual selective attention following TBI. Principal components analysis revealed a four-component/factor structure of attention, largely consistent with previous studies. A logistic regression found that the TEA Map Search and Modified Colour-Word subtest of the Stroop were best able to discriminate between the TBI and control groups. When the TBI group was divided into Early (< 1 year post injury) and Late (> 2 years post injury) groups, there was an additional deficit on the Lottery (sustained attention) subtest in the Early TBI group, indicating that there is some recovery in attentional function beyond 1 year post injury.

Prospective and declarative memory problems following moderate and severe traumatic brain injury

Primary objective: To examine prospective and declarative memory problems following moderate and severe traumatic brain injury (TBI) and the relationship between prospective memory (PM) and declarative memory and PM and other cognitive functions. Research design: The performance of persons who suffered a TBI (n = 25) was compared with that of a demographically matched control group (n = 25). Methods and procedures: Measures of time- and event-based PM, visual and verbal declarative memory, attention and executive functioning were administered to both groups. Main outcome and results: The group with a TBI performed more poorly on event- and time-based PM, verbal declarative memory, certain aspects of attention and executive functioning. The correlations between the measures of PM, declarative memory and the other cognitive tests were all non-significant. Conclusions: Problems with declarative memory, attention, and executive functioning do not adequately account for poorer PM performance following a TBI, suggesting that PM should also be assessed following TBI.

Neuropsychological and Information Processing Performance and Its Relationship to White Matter Changes Following Moderate and Severe Traumatic Brain Injury: A Preliminary Study

Reductions in information processing speed have frequently been reported following moderate and severe traumatic brain injuries (TBIs), consistent with the effects of diffuse white matter damage. Although the corpus callosum (CC) is a common site for diffuse damage following TBI, the effects of this damage on information processing speed have not been adequately examined. This study assessed a TBI group and a matched control group on tests of attention, memory, fluency, and set shifting ability, together with reaction time (RT) tasks requiring the inter- and intrahemispheric processing of visual and tactile information. The RT tasks were designed to target the cognitive functions that are likely to be affected by diffuse white matter damage, including damage to the CC. The TBI group demonstrated deficits in verbal and visual fluency and verbal memory. They were also slower on the visual and tactile RT tasks, were more affected by task complexity, and slower on RT tasks requiring the interhemispheric transfer of information. In fact, one of the interhemispheric tactile RT tasks proved to be the most discriminating of all the cognitive and RT measures. MRIs completed on a subset of TBI participants indicated that the mean CC measurements were 5% to 19% smaller than a normative control group, with the most atrophied areas being the isthmus and anterior midbody. Although white matter atrophy was moderately related to visual and tactile RT performance, and total hippocampal volume related to memory performance, CC area was not related to many of the tasks that were designed to tap interhemispheric processing. None of the standard cognitive tests correlated with outcome in the TBI group, but 1 of the tactile RT measures was significantly related to 2 measures of outcome.

The Psychological Functioning of Children from Backgrounds of Domestic Violence

Abstract The present study examined the psychological functioning of children who came from backgrounds of domestic violence. Phase I provided a descriptive analysis of the emotional and behavioural problems, social competence, reading skills, anxiety levels, and conflict response styles of 79 children, aged 6 to 12 years, who had previously lived in domestically violent situations. Phase II compared the scores of 22 of these children with the scores of 22 children who had no history of domestic violence, and who were matched to the former group on the basis of age, sex, reading skills, and socioeconomic status. The results for Phase I indicated that between 52% and 63% of the domestic violence group showed borderline to severe levels of behaviour problems; 52% had below-average adaptive behaviour skills; and over 43% had reading ages which were more than one year below their chronological ages. Moderately high to high levels of anxiety were evident in only 15% of children, and significantly more assertiv...

Cognitive functioning in chronic fatigue syndrome: a meta-analysis

BACKGROUND Cognitive problems are commonly reported in persons with chronic fatigue syndrome (CFS) and are one of the most disabling symptoms of this condition. A number of cognitive deficits have been identified, although the findings are inconsistent and hindered by methodological differences. The current study therefore conducted a meta-analysis of research examining cognitive functioning in persons with CFS in order to identify the pattern and magnitude of any deficits that are associated with this condition. METHOD A comprehensive search of the PubMed and PsycINFO databases for studies that examined cognitive functioning in CFS between 1988 and 2008 identified 50 eligible studies. Weighted Cohens d effect sizes, 95% confidence intervals and fail-safe Ns were calculated for each cognitive score. RESULTS Evidence of cognitive deficits in persons with CFS was found primarily in the domains of attention, memory and reaction time. Deficits were not apparent on tests of fine motor speed, vocabulary, reasoning and global functioning. CONCLUSIONS Persons with CFS demonstrate moderate to large impairments in simple and complex information processing speed and in tasks requiring working memory over a sustained period of time.