Cognitive remediation in residential substance use treatment: A randomized stepped-wedge trial.

ABSTRACTExecutive dysfunction is common in individuals with substance use disorder (SUD) and presents a barrier to treatment engagement. The study aimed to investigate the effectiveness of cognitive remediation (CR) for improving executive functioning and treatment retention in patients with SUD, using a stepped-wedge cluster randomized controlled trial. The sample included 527 adults enrolled across ten residential SUD treatment providers in NSW, Australia. The intervention consisted of 12 hours of CR delivered over six weeks in a group format. The comparator was treatment-as-usual (TAU). Primary outcomes included self-reported executive functioning and proportion of treatment completed (PoTC), measured as the number of days in treatment divided by the planned treatment duration. Intention-to-treat analysis did not find significant differences for self-reported executive functioning (mean difference = -2.49, 95%CI [-5.07, 0.09], p = .059) or PoTC (adjusted mean ratio = 1.09, 95%CI [0.88, 1.36], p = .442). Due to high dropout from the intention-to-treat sample (56%) a post-hoc analysis was conducted using a per-protocol approach, in which CR was associated with improved self-reported executive functioning (mean difference = -3.33, 95%CI [-6.10, -0.57], p = .019) and improved likelihood of treatment graduation (adjusted odds ratio = 2.43, 95%CI [1.43, 4.11], p < .001). More research is required to develop a CR approach that results in service-wide treatment effectiveness.

Neuropsychological Deficits in Disordered Screen Use Behaviours: A Systematic Review and Meta-analysis.

Over the last few decades, excessive and disordered screen use has become more prevalent, prompting investigations into its associated consequences. The extent to which disordered screen use behaviours impact neuropsychological functioning has been reportedly mixed and at times inconsistent. This review sought to synthesise the literature and estimate the magnitude of overall cognitive impairment across a wide range of disordered screen use behaviours. We also sought to determine the cognitive domains most impacted, and whether the observed impairments were moderated by the classification of screen-related behaviours (i.e., Internet or gaming) or the format of cognitive test administration (i.e., paper-and-pencil or computerised). A systematic search of databases (Embase, PsycINFO, MEDLINE) identified 43 cross-sectional articles that assessed neuropsychological performance in disordered screen use populations, 34 of which were included in the meta-analysis. A random-effects meta-analysis revealed significant small/medium (g = .38) cognitive deficits for individuals with disordered screen use behaviours relative to controls. The most affected cognitive domain with a significant medium effect size (g = .50) was attention and focus followed by a significant reduction in executive functioning (g = .31). The classification of disordered screen use behaviours into Internet or gaming categories or the format of cognitive testing did not moderate these deficits. Additionally, excluding disordered social media use in an exploratory analysis had little effect on the observed outcomes. This study highlights a number of methodological considerations that may have contributed to disparate findings and shows that disordered screen use can significantly impact cognitive performance. Recommendations for future research are also discussed. Data for this study can be found at https://osf.io/upeha/ .

Not all mentally stimulating activities are alike: insights from a 4-factor model and implications for late-life cognition.

It is not yet known which specific qualities of cognitively stimulating activities are most likely to enhance cognitive reserve in older adults. Taking an inductive approach to this problem, we asked 504 older adults with subjective and/or cognitive impairment to complete the Cognitively Stimulating Activities Questionnaire (CSA-Q). Exploratory factor analysis identified a 4-factor structure within a split-half sample, after which confirmatory factor analysis cross-validated the model. Retaining 12 CSA-Q items, the 4 factors were dubbed CSA-Processing, CSA-Challenging, CSA-Connecting and CSA-Socializing. Resulting factor weights were analyzed relative to cognitive reserve proxies and neuropsychological domains. All factors except CSA-Challenging were positively linked to cognitive reserve. Neuropsychologically, CSA-Challenging was modestly and positively correlated with processing speed and executive function, while CSA-Processing was positively correlated with executive function. CSA-Socializing had a small positive correlation with processing speed. Our findings offer new insights into late-life stimulating activities, laying the groundwork for longitudinal and intervention studies.

Fifteen minutes of high intensity running can impair performance on concussion testing; Implications for on-field diagnosis in sport.

OBJECTIVES: To examine the effects of 15 min of high intensity treadmill running on concussion testing assessed by the King-Devick test. DESIGN: Prospective Cohort Study. METHODS: Participants self-selected to either a running or a control group. At baseline both groups were assessed using the King-Devick concussion test. The running group then completed 15-minutes of treadmill running at rating of perceived exertion of 7-9/10 while the control group sat quietly. Both groups repeated the King-Devick test following that 15-minute period. RESULTS: Participants (n = 84 men, 53 women) were divided in two groups; running or control. Both groups, on average, had significant improvement after 15 min (suggesting a learning effect). Comparisons between the baseline and re-assessment scores indicated impaired performance was more common following high intensity treadmill running (n = 23 participants, 34.3%) compared to the control group (n = 10 participants, 14.3%, p = 0.006, OR = 3.44 [95%CI 1.40-8.50]). Four participants in the running group worsened their score at reassessment by more than 3 s compared to no participants in the control group. CONCLUSIONS: After 15 min of high intensity treadmill running, 1 in 3 participants scored a slower time at follow-up or committed a mistake compared to baseline. Implications for clinical practise include: the recommendation that baseline tests be conducted at rest and after high intensity exercise to provide accurate comparisons to assist in clinical decision making; and a cut-off of >3 s may be a clinically useful difference between resting baseline and re-assessment using the King-Devick test.

Psychometric Properties of a New Decision-Making Capacity Assessment Tool for People with Substance Use Disorder: The CAT-CAT.

Individuals with substance use disorder (SUD) often present with cognitive impairments, which may impede their ability to make decisions for themselves, including treatment-related decisions. It is therefore important to assess whether individuals with SUD have adequate decision-making capacity. Indeed, there have not been any capacity assessment tools tailored for use with SUD populations that demonstrate adequate psychometric properties or that have the strong ethical foundation that is required of capacity assessment tools. The Compulsory Assessment and Treatment-Capacity Assessment Tool (CAT-CAT) was designed to fill this gap in the literature. Therefore, the aim of this study was to establish the interrater and test-retest reliability, and discriminative validity of the CAT-CAT. The first of this two-part study recruited healthcare professionals in New Zealand and asked them to conduct a capacity assessment on two hypothetical clients. Generally, excellent interrater reliability (ρ = .998 overall) and test-retest reliability (ρ = .996 overall) was found. The CAT-CAT has exhibited reliability that was at least comparable to widely used capacity assessment tools for other pathologies. The second part of this study involved cognitively normal individuals undergoing capacity assessments to investigate the hypothesis that individuals that do not lack capacity will obtain scores significantly higher than 50% in each section of the CAT-CAT. This hypothesis was met with highly significant results. To conclude, preliminary data suggest that the CAT-CAT has excellent reliability and correctly classifies those with capacity.

The Alcohol and Drug Cognitive Enhancement (ACE) Screening Tool: A simple and brief questionnaire to screen for cognitive impairment in substance use disorder treatment services.

The objective of this study was to determine the test-retest reliability; construct and criterion validity; and test operating characteristics of a newly developed cognitive impairment risk factor screening instrument, the Alcohol and Drug Cognitive Enhancement (ACE) Screening Tool. Participants in the validation study were 129 adults with substance use disorder (SUD) enrolled in residential SUD treatment services and 209 normal controls. Test and retest data were available for 36 participants with SUD and 40 normal control individuals on the ACE Screening Tool. Test-retest reliability was excellent (ICC = 0.97). The ACE Screening Tool was significantly correlated with the Montreal Cognitive Assessment (MoCA), Behavior Rating Inventory of Executive Functioning-Adult Version (BRIEF-A), Test of Premorbid Functioning (TOPF) and Five Point Test, establishing construct validity. Criterion validity was established using a ternary severity variable constructed using results obtained on the MoCA and BRIEF-A. Test operating characteristics analysis showed 93% sensitivity, 46% specificity, 33% positive predictive power, and 96% negative predictive power using a cut-score of >3. Those high levels of sensitivity and negative predictive power indicated that the tool would likely detect cognitive impairment when present and should therefore be considered suitable as an initial screening tool for cognitive impairment in individuals attending SUD services.

Cognitive Remediation as an Adjunct Treatment for Substance Use Disorders: A Systematic Review.

Substance use disorders are associated with diverse neuropsychological impairments, with deficits in memory and executive functioning commonly observed. Cognitive remediation has been shown to be effective in other populations with cognitive impairments in these domains, including those with psychiatric disorders and acquired brain injuries, and it has been hypothesised to be similarly effective for those in treatment for substance use disorders. We aimed to systematically review the evidence for cognitive remediation interventions administered as an adjunct treatment to substance use rehabilitation. Studies were included if participants were receiving substance use treatment, if improving cognitive functioning was the main focus of the intervention and if they used an experimental design with a control condition receiving treatment-as-usual or an active control intervention. Two independent reviewers agreed on the final selection of 32 studies, encompassing cognitive remediation for working memory, memory, executive functioning and general cognition. Significant differences between intervention and control groups for cognitive test results and treatment outcomes were extracted and compared across treatment approaches. The review found considerable heterogeneity across studies, including in the types of interventions, the nature of participants and the outcome measures used. Further, a lack of quality studies with sufficient power meant that limited conclusions could be drawn, highlighting a need for further replication and research. However, findings indicate that cognitive remediation remains a promising potential avenue for improving cognition and treatment outcomes for those in treatment for substance use disorders. Protocol submitted prospectively to PROSPERO 30.09.2019, CRD42020150978.

Engagement in cognitively stimulating activities in individuals with Mild Cognitive Impairment: relationships with neuropsychological domains and hippocampal volume.

Late-life participation in cognitively stimulating activities is thought to contribute to an individual's cognitive reserve and thus protect against cognitive decline, yet its association with clinical markers of neurodegeneration is not well established. To investigate, we developed a 13-item self-report "cognitively stimulating activities" questionnaire (CSA-Q), which was completed by a community sample of 269 older adults (>50 years) at risk of dementia. Participants met criteria for Mild Cognitive Impairment (MCI) and were classified as amnestic (aMCI; n = 93) or non-amnestic (naMCI; n = 176). Weighted CSA-Q dimensions were calculated for activity intensity, mental engagement and social engagement via a panel of 23 inter-raters. The CSA-Q mean and its dimensions were examined in relation to: (a) demographics (age, sex), (b) cognitive reserve proxies (years of education, premorbid IQ), (c) neuropsychological markers across cognitive domains of executive function, processing speed, learning, and memory storage, and (d) neuroimaging markers (left and right hippocampal volume). Analyses were conducted for all MCI, as well as for aMCI and naMCI sub-types. The CSA-Q was found to have concurrent validity with cognitive reserve proxies. Among all MCI, the CSA-Q dimensions of intensity and mental engagement had moderate associations with left hippocampal volume, but not with neuropsychological performance. For naMCI, the CSA-Q had moderate associations with left hippocampal volume, and small associations with aspects of executive functioning and processing speed. No equivalent associations emerged for the aMCI subtype. Our findings show that the CSA-Q may be particularly useful for older adults with non-amnestic cognitive deficits.

Diffusion Tensor Imaging in Sport-Related Concussion: A Systematic Review Using an a priori Quality Rating System.

Diffusion tensor imaging (DTI) of brain white matter (WM) may be useful for characterizing the nature and degree of brain injury after sport-related concussion (SRC) and assist in establishing objective diagnostic and prognostic biomarkers. This study aimed to conduct a systematic review using an a priori quality rating strategy to determine the most consistent DTI-WM changes post-SRC. Articles published in English (until June 2020) were retrieved by standard research engine and gray literature searches (N = 4932), using PRISMA guidelines. Eligible studies were non-interventional naturalistic original studies that conducted DTI within 6 months of SRC in current athletes from all levels of play, types of sports, and sex. A total of 29 articles were included in the review, and after quality appraisal by two raters, data from 10 studies were extracted after being identified as high quality. High-quality studies showed widespread moderate-to-large WM differences when SRC samples were compared to controls during the acute to early chronic stage (days to weeks) post-SRC, including both increased and decreased fractional anisotropy and axial diffusivity and decreased mean diffusivity and radial diffusivity. WM differences remained stable in the chronic stage (2-6 months post-SRC). DTI metrics were commonly associated with SRC symptom severity, although standardized SRC diagnostics would improve future research. This indicates that microstructural recovery is often incomplete at return to play and may lag behind clinically assessed recovery measures. Future work should explore interindividual trajectories to improve understanding of the heterogeneous and dynamic WM patterns post-SRC.

Rates of false positive outcomes on the A-WPTAS picture items in a sample of non-concussed athletes.

Accurate diagnosis of sports related concussion ensures that athletes are removed from play if concussed and prevents incorrect removal when a concussion has not occurred. Although various screening tools are currently in use, there is no gold standard measure with which to diagnose sports related concussion.Objective: The current study aimed to investigate the diagnostic accuracy of the Abbreviated Westmead Post Traumatic Amnesia Scale (A-WPTAS) picture task, a neurocognitive measure used to assess mild traumatic brain injury. The incidence of false positive classifications and the potential confounding effect of exercise on scores on the A-WPTAS picture items were examined.Methods: The study included an athlete group comprising 33 players and a control group comprising 37 subjects. The A-WPTAS picture task was completed on three testing occasions, separated by three week intervals.Results: Results revealed that the A-WPTAS picture task was highly accurate (>95%) in correctly classifying participants with no concussion across all three testing occasions. There was no significant difference between the two groups in relation to false positive outcomes on any testing occasion, suggesting that exercise was not a confounding factor.Conclusions: Findings provide preliminary evidence to support the use of the A-WPTAS picture task in a sporting context.

Chronic Neurophysiological Effects of Repeated Head Trauma in Retired Australian Male Sport Athletes.

Aim: This study investigated the somatosensory and corticomotor physiology of retired contact sport athletes with a history of repeated concussion/subconcussion head trauma. Methods: Retired male athletes with a history of playing contact sports and repeated head trauma (n = 122) were divided into two groups: those who expressed concerns regarding their mental and cognitive health ("symptomatic": n = 83), and those who did not express any ongoing concerns ("asymptomatic": n = 39). Both groups were compared to age-matched male controls (n = 50) with no history of concussions or participation in contact sports, an absence of self-reported cognitive, or mood impairments. Transcranial magnetic stimulation (TMS) and vibrotactile stimulation were used to assess corticomotor and somatosensory pathways respectively. TMS and vibrotactile stimulation were correlated to self-reported responses using the Fatigue and Related Symptom Survey. Linear regression was used to associate concussion history with TMS, somatosensory variables. Results: Significant differences were found in symptom survey scores between all groups (p < 0.001). TMS showed significant differences between the "symptomatic" and control groups for intracortical inhibition and paired pulse TMS measures. Somatosensory measures showed significant differences for reaction time (p < 0.01) and reaction time variability (p < 0.01) between the "symptomatic" group to the "asymptomatic" and control groups. For other somatosensory measures, the "symptomatic" measures showed differences to the "control" group. Correlations showed significant associations between severity of symptom reporting with TMS and somatosensory measure, and regression revealed the number of concussions reported was shown to have significant relationships to increased intracortical inhibition and poorer somatosensory performance. Conclusion: This study shows that retired contact sport athletes expressing chronic symptoms showed significant pathophysiology compared to those with no ongoing concerns and non-concussed controls. Further, there is a linear dose-response relationship between number of reported concussions and abnormal neurophysiology. Neurophysiological assessments such as TMS and somatosensory measures represent useful and objective biomarkers to assess cortical impairments and progression of neuropsychological impairment in individuals with a history of repeated head trauma.

Cognitive abilities in Williams syndrome.

The current study utilized a comprehensive neuropsychological test battery to investigate cognitive abilities in a sample of 49 WS individuals (25 male) aged 6-39 years. Age effects were also investigated by splitting the sample into child and adult groups. Cognitive heterogeneity was found on the Woodcock Johnson III Tests of Cognitive Abilities, Australian Adaptation (WJ-III COG) (Woodcock, McGrew, & Mather, 2001), with cognitive abilities ranging from profoundly impaired to superior and individualized profiles of strength and weakness varying considerably. Overall, findings supported previous research showing strengths in auditory processing and phonemic awareness. The weakest performance, on average, was in processing speed, attention, delayed associative learning and executive functioning capabilities. Visual-spatial functioning was not a weakness overall, neither was nonverbal reasoning. Chronological age did not relate significantly to cognitive abilities. Findings highlight the need for individual assessment and management of WS individuals.

An examination of the heterogeneity of cognitive outcome following severe to extremely severe traumatic brain injury.

Objective: The current study aimed to explore neuropsychological outcomes in the initial recovery period following severe to extremely severe traumatic brain injury (TBI).Method: Using reliable change statistics, individuals were categorized as demonstrating cognitive improvement, stability or decline based on performance on 11 neuropsychological measures relative to scores returned during an initial assessment conducted in the acute post-injury stage. The study explored injury, demographic, and other variables as predictors of group membership. A total of 79 individuals were recruited from retrospective neuropsychological records between 2009 and 2017. Individuals were assessed on two occasions as per routine clinical practice. Approximately 10% of subjects sustained a severe TBI, 52% sustained a very severe TBI, and 38% sustained an extremely severe TBI.Results: Of the 79 participants, two individuals (2.5%) demonstrated cognitive decline, 28 individuals (35.4%) demonstrated cognitive stability, and 49 individuals (62%) demonstrated cognitive improvement. A binary logistic regression indicated that length of post-traumatic amnesia, as a categorical variable, was significantly predictive of group membership in that those with extremely severe TBIs were more likely to show improvement over time. Additionally, high levels of stress at review assessment, as measured on the Depression Anxiety Stress Scales, was predictive of membership in the cognitive improvement group.Conclusion: The results highlighted the heterogeneity of recovery in the initial recovery period following severe to extremely severe TBI and have the potential to inform clinical advice regarding outcome trajectories.

Length of post-traumatic amnesia and its prediction of neuropsychological outcome following severe to extremely severe traumatic brain injury in a litigating sample.

Primary Objective: The aim of the current study was to examine the relationship between duration of post-traumatic amnesia (PTA) and neuropsychological outcome at one or more years following severe to extremely severe traumatic brain injury (TBI) in a litigating sample. Research Design: Retrospective study design, using data collected from 2010 to 2017. Methods and Procedures: Data from 41 cases obtained from a private medicolegal neuropsychological database was examined. The database comprised information pertaining to TBI etiology, TBI severity parameters, demographic variables, neuropsychological test results and scores on psychological questionnaires. PTA duration was examined as a continuous variable. All cases that demonstrated non-credible effort were excluded. Main Outcomes and Results: Continuous PTA duration was not found to be a significant predictor of cognitive impairment across domains of verbal intellect, non-verbal intellect, working memory, information processing speed, immediate memory, delayed memory, and executive functioning. Conclusions: The predictive relationship between duration of PTA and cognitive impairment that has been reported in non-litigating populations did not exist in a litigating TBI sample. Findings illustrate the importance of investigating the relationships between injury variables and cognitive outcome in a population undergoing litigation, to provide better understanding of outcome in this subgroup of patients with TBI.

Current sleep disturbance in older people with a lifetime history of depression is associated with increased connectivity in the Default Mode Network.

BACKGROUND: The present study investigated Default Mode Network (DMN) functional connectivity in subjects with a lifetime history of major depression, comparing those with and without current sleep disturbance. Controls were included to assess DMN abnormalities specific to depression. METHODS: A total of 93 adults aged 50 years and over were recruited from the Healthy Brain Ageing Clinic at the Brain and Mind Centre, Sydney, Australia. The sample comprised two groups, including 22 controls and 71 participants with a lifetime history of DSM-IV major depression (with depressive episode current or remitted). 52 of those with a lifetime history of depression also met criteria for Mild Cognitive Impairment (MCI). Participants underwent resting-state fMRI along with comprehensive psychiatric, neuropsychological, and medical assessment. Subjective sleep quality was assessed via the Pittsburgh Sleep Quality Index (PSQI). Sleep disturbance was defined as a PSQI score > 5. A total of 68% (n = 48) of cases with a lifetime history of depression met criteria for sleep-disturbance. DMN functional connectivity was assessed via ROI-to-ROI analyses. RESULTS: Relative to controls, those with lifetime major depression demonstrated significantly increased functional connectivity between the ventromedial prefrontal cortex and the temporal pole. Within the depression group (n = 48), those with current sleep disturbance had significantly increased connectivity between the anterior medial prefrontal cortex and both the parahippocampal cortex and the hippocampal formation, relative to those without sleep disturbance (n = 23). These results were present after controlling for MCI diagnosis. CONCLUSIONS: Current sleep disturbance together with depression is associated with distinct abnormalities in DMN functioning incorporating regions responsible for self-reflection and declarative memory processes. Impaired sleep is associated with increased connectivity between these regions. Future studies may augment these findings with complementary imaging techniques including cortical thickness and diffusion tensor imaging, as well as high density electroencephalogram recording.

Cognitive screening in substance users: Diagnostic accuracies of the Mini-Mental State Examination, Addenbrooke's Cognitive Examination-Revised, and Montreal Cognitive Assessment.

INTRODUCTION: Despite the considerable prevalence of cognitive impairment in substance-using populations, there has been little investigation of the utility of cognitive screening measures within this context. In the present study the accuracy of three cognitive screening measures in this population was examined-the Mini-Mental State Examination (MMSE), the Addenbrooke's Cognitive Examination-Revised (ACE-R), and the Montreal Cognitive Assessment (MoCA). METHOD: A sample of 30 treatment-seeking substance users and 20 healthy individuals living in the community were administered the screening measures and a neuropsychological battery (NPB). Agreement of classification of cognitive impairment by the screening measures and NPB was examined. RESULTS: Results indicated that the ACE-R and MoCA had good discriminative ability in detection of cognitive impairment, with areas under the receiver-operating characteristic (ROC) curve of .85 (95% confidence interval, CI [.75. .94] and .84 (95% CI [.71, .93]) respectively. The MMSE had fair discriminative ability (.78, 95% CI [.65, .93]). The optimal cut-score for the ACE-R was 93 (impairment = score of 92 or less), at which it correctly classified 89% of individuals as cognitively impaired or intact, while the optimal cut-score for the MoCA was <26 or <27 depending on preference for either specificity or sensitivity. The optimal cut-score for the MMSE was <29; however, this had low sensitivity despite good specificity. CONCLUSIONS: These findings suggest that the MoCA and ACE-R are both valid and time-efficient screening tools to detect cognitive impairment in the context of substance use.

Functional Connectivity in the Default Mode Network is Reduced in Association with Nocturnal Awakening in Mild Cognitive Impairment.

BACKGROUND: Sleep disturbance is prevalent in MCI, and is a risk factor for cognitive deterioration. OBJECTIVE: To identify functional connectivity deficits in the default mode network (DMN) in patients with mild cognitive impairment (MCI) and sleep disturbance, relative to MCIs with intact sleep. METHODS: Participants comprised 47 adults aged 55 years and over, recruited from the Healthy Brain Ageing Clinic at the Brain and Mind Centre, Sydney, Australia. This sample contained 15 controls and 32 participants meeting criteria for MCI. Participants underwent resting-state fMRI and actigraphy, along with comprehensive neuropsychological, medical and psychiatric assessment. MCIs were split into two groups according to average wake after sleep onset (WASO) per night. WASO equal to or greater than 1 standard deviation (SD) above the control mean was deemed to reflect disturbed sleep. There were 11 patients in the MCI sleep-disturbed group, and 21 in the MCI sleep-intact group. RESULTS: Relative to controls, MCIs demonstrated significant connectivity reductions between parietal and temporoparietal regions, and between temporal regions. Relative to MCIs with intact sleep, MCIs with sleep disturbance demonstrated reductions in functional connectivity between temporal and parietal regions, and between temporal and temporoparietal regions. CONCLUSIONS: MCIs with nocturnal awakenings demonstrate reductions in DMN connectivity. These reductions comprise brain regions that are crucially involved in sleep and memory processes. These results strengthen our previous findings, which found reduced connectivity in MCIs with self-reported sleep disturbances. Future studies may build on these findings through incorporating complementary neuroimaging techniques and experimental manipulations of sleep.

Cognitive Tests and Determining Fitness to Drive in Dementia: A Systematic Review.

Evidence has shown that although all individuals with dementia will eventually need to stop driving, most can continue to drive safely early in the disease. Fitness to drive needs to be monitored, and the use of cognitive testing to determine driver safety has been suggested. This review is the first to examine cognitive test results pertaining only to individuals with dementia. The aim was to examine the relationship between cognitive tests and driving to determine whether a cognitive assessment can be implemented as a tool to examine driver safety. A systematic review of 28 studies investigating the relationship between cognitive functioning and driving in individuals with dementia was conducted. The results of this review demonstrated a lack of consistency in the findings, with some studies showing a relationship between cognitive testing and driving performance for individuals with dementia, whereas others did not. Results relating to individual cognitive tests and measures confined to a single cognitive domain were variable and not consistently associated with driving performance. Studies consistently found that composite batteries predicted driving performance. The findings from this review support the use of composite batteries comprising multiple individual tests from different cognitive domains in predicting driving performance for individuals with dementia. Scores on individual tests or tests of a single cognitive domain did not predict driver safety. The composite batteries that researchers have examined are not clinically usable because they lack the ability to discriminate sufficiently between safe and unsafe drivers. Researchers need to develop a reliable, valid composite battery that can correctly determine driver safety in individuals with dementia.

Sleep disturbance in mild cognitive impairment is associated with alterations in the brain's default mode network.

This study aimed to identify default mode network (DMN) functional connectivity deficits in patients with mild cognitive impairment (MCI) and sleep disturbance, relative to those with MCI and no sleep disturbance. A control group was included to aid in identifying DMN changes specific to MCI. A cross-sectional, single-center study was performed at the Brain and Mind Research Centre in Sydney, Australia. Participants (95 adults over the age of 65: 38 controls and 57 meeting criteria for MCI) underwent resting-state functional MRI along with comprehensive neuropsychological, medical, and psychiatric assessment. Self-report data were collected including sleep quality assessment via the Pittsburgh Sleep Quality Index. A total score of greater than 5 on the Pittsburgh Sleep Quality Index was used to signify the presence of significant sleep disturbance, as per commonly used methodology. Using this criterion, 53% (n = 30) of our MCI group were classified as sleep-disturbed. Whereas the total group of MCI subjects and controls demonstrated no significant differences, sleep-disturbed MCIs demonstrated increased connectivity between temporal and parietal regions, and decreased connectivity between the prefrontal cortex and the temporoparietal junction relative to sleep-disturbed controls. Relative to those MCIs without sleep disturbance, sleep-disturbed MCI participants demonstrated significantly diminished DMN connectivity between temporal and parietal regions, a finding that was particularly pronounced in amnestic MCI. Sleep disturbance in MCI is associated with distinct alterations in DMN functional connectivity in brain regions underpinning salient memory and sleep systems. Future studies may build on these results via experimental manipulation and objective measurement of sleep. (PsycINFO Database Record