Cognitive and neural plasticity in old age: A systematic review of evidence from executive functions cognitive training

Cognitive training is a popular intervention aimed at attenuating age-related cognitive decline, however, the effects of this intervention on brain structure and function have not been thoroughly explored. Core executive functions (working memory, inhibition, cognitive flexibility) are dependent upon prefrontal brain regions—one of the most vulnerable areas of age-related decline. They are also implicated in numerous cognitive processes and higher-order functions. Training executive functions should therefore promote cognitive and neural enhancements in old age. This systematic review examined the effects of executive functions training on brain and cognition amongst healthy older adults across 20 studies. Behavioral performance consistently improved on trained cognitive tasks, though mixed findings were reported for untrained tasks. Training-related structural changes were reported, evidenced through increases in grey matter and cortical volume. Functional changes were not consistent, though a general pattern of increased subcortical and decreased frontal and parietal activation emerged across studies, indicating that training may potentially reduce reliance on compensatory neural mechanisms. Training executive functions appears to promote cognitive and neural plasticity in old age, though further research is required to develop a more comprehensive framework which connects and elucidates the mechanisms underlying cognitive training, cognitive transfer, and cognitive aging.     

The impact of cognitive training and mental stimulation on cognitive and everyday functioning of healthy older adults: A systematic review and meta-analysis

This systematic review and meta-analysis investigates the impact of cognitive training and general mental stimulation on the cognitive and everyday functioning of older adults without known cognitive impairment. We examine transfer and maintenance of intervention effects, and the impact of training in group versus individual settings. Thirty-one randomised controlled trials were included, with 1806 participants in cognitive training groups and 386 in general mental stimulation groups. Meta-analysis results revealed that compared to active controls, cognitive training improved performance on measures of executive function (working memory, p = 0.04; processing speed, p < 0.0001) and composite measures of cognitive function (p = 0.001). Compared to no intervention, cognitive training improved performance on measures of memory (face-name recall, p = 0.02; immediate recall, p = 0.02; paired associates, p = 0.001) and subjective cognitive function (p = 0.01). The impact of cognitive training on everyday functioning is largely under investigated. More research is required to determine if general mental stimulation can benefit cognitive and everyday functioning. Transfer and maintenance of intervention effects are most commonly reported when training is adaptive, with at least ten intervention sessions and a long-term follow-up. Memory and subjective cognitive performance might be improved by training in group versus individual settings.     

Effective multicomponent interventions in comparison to active control and no interventions on physical capacity,cognitive function and instrumental activities of daily living in elderly people with and without mild impaired cognition – A systematic review and network meta-analysis

Multicomponent interventions (MCT) combine physical exercises and cognitive training and seem to be most effective in improving cognition in elderly people. However, literature is inconclusive if MCTs are superior to active comparison interventions, if delivery modes matter, and if people can transfer achieved effects to instrumental activities of daily living (IADL). This network meta-analysis aimed to a) identify MCTs that were effective on physical capacity and/or cognitive function and able to transfer these effects into IADL in elderly people with normal cognition (NC) and mild cognitive impairment (MCI); b) provide a rating on the best interventions per outcome; c) evaluate MCTs’ mode of delivery. Eligible studies were randomized controlled trials comparing MCTs to active comparison or no treatments. Six studies in participants with MCI (n = 1088) and eleven studies in participants with NC (n = 670) were included. Five effective MCTs that were superior to physical exercises or cognitive training alone in improving physical capacity and/or cognitive function were detected, however none of these MCTs improved IADL. In people with NC MCTs performed separately or simultaneously were effective. However, in people with MCI MCTs performed separately were more effective. A framework needs to be developed to better understand the mediating effects of physical capacity and cognitive function on IADL and to design MCTs that effectively improve IADL.     

Cognitive training and Bacopa monnieri: Evidence for a combined intervention to alleviate age associated cognitive decline

As the elderly population grows the impact of age associated cognitive decline as well as neurodegenerative diseases such as Alzheimer’s disease and dementia will increase. Ageing is associated with consistent impairments in cognitive processes (e.g., processing speed, memory, executive function and learning) important for work, well-being, life satisfaction and overall participation in society. Recently, there has been increased effort to conduct research examining methods to improve cognitive function in older citizens. Cognitive training has been shown to improve performance in some cognitive domains; including memory, processing speed, executive function and attention in older adults. These cognitive changes are thought to be related to improvements in brain connectivity and neural circuitry. Bacopa monnieri has also been shown to improve specific domains of cognition, sensitive to age associated cognitive decline (particularly processing speed and memory). These Bacopa monnieri dependent improvements may be due to the increase in specific neuro-molecular mechanisms implicated in the enhancement of neural connections in the brain (i.e. synaptogenesis). In particular, a number of animal studies have shown Bacopa monnieri consumption upregulates calcium dependent kinases in the synapse and post-synaptic cell, crucial for strengthening and growing connections between neurons. These effects have been shown to occur in areas important for cognitive processes, such as the hippocampus. As Bacopa monnieri has shown neuro-molecular mechanisms that encourage synaptogenesis, while cognitive training enhances brain connectivity, Bacopa monnieri supplementation could theoretically enhance and strengthen synaptic changes acquired through cognitive training. Therefore, the current paper hypothesises that the combination of these two interventions could improve cognitive outcomes, over and above the effects of administrating these interventions independently, as an effective treatment to ameliorate age associated cognitive decline.     

Effect of a Kinect-Based Exercise Game on Improving Executive Cognitive Performance in Community-Dwelling Elderly: Case Control Study

Background

Decrease of dual-task (DT) ability is known to be one of the risk factors for falls. We developed a new game concept, Dual-Task Tai Chi (DTTC), using Microsoft’s motion-capture device Kinect, and demonstrated that the DTTC test can quantitatively evaluate various functions that are known risk factors for falling in elderly adults. Moreover, DT training has been attracting attention as a way to improve balance and DT ability. However, only a few studies have reported that it improves cognitive performance.

Objective

The purpose of this study was to demonstrate whether or not a 12-week program of DTTC training would effectively improve cognitive functions.

Methods

This study examined cognitive functions in community-dwelling older adults before and after 12 weeks of DTTC training (training group [TG]) or standardized training (control group [CG]). Primary end points were based on the difference in cognitive functions between the TG and the CG. Cognitive functions were evaluated using the trail-making test (part A and part B) and verbal fluency test.

Results

A total of 41 elderly individuals (TG: n=26, CG: n=15) participated in this study and their cognitive functions were assessed before and after DTTC training. Significant differences were observed between the two groups with significant group × time interactions for the executive cognitive function measure, the delta-trail-making test (part B−part A; F _1,36=4.94, P=.03; TG: pre mean 48.8 [SD 43.9], post mean 42.2 [SD 29.0]; CG: pre mean 49.5 [SD 51.8], post mean 64.9 [SD 54.7]).

Conclusions

The results suggest that DTTC training is effective for improving executive cognitive functions.

Trial Registration

Japan Medical Association Clinical Trial Registration Number: JMA-IIA00092; https://dbcentre3.jmacct.med.or.jp/jmactr/App/JMACTRS06/JMACTRS06.aspx?seqno=2682 (Archived by WebCite at http://www.webcitation.org/6NRtOkZFh).     

Computerized cognitive training in Parkinson’s disease: A systematic review and meta-analysis

Cognitive impairment is a central non-motor symptom of Parkinson’s disease (PD), and there are no established treatments. Computerized cognitive training (CCT) is a safe and efficacious strategy but its efficacy in PD is unclear. We aimed to investigate the efficacy of CCT on cognitive, psychosocial and daily function, and assess potential effect moderators in people with PD without dementia. Randomized controlled trials of CCT were included in multivariate meta-analyses and meta-regressions. Seventeen studies (16 trials) encompassing 679 participants were included. The pooled effect of CCT relative to control was small and statistically significant for overall cognitive function (g=0.16; 95% CI 0.02–0.29). There was robust evidence for benefit on clinical measures of global cognition across 10 trials (g=0.33; 95% CI 0.19–0.48), especially in PD with mild cognitive impairment (PD-MCI), as well as on individual cognitive domains. Greater CCT dose and PD-MCI population were associated with larger effect sizes, but no statistically significant differences were found between subgroups. There was no significant difference in the efficacy of home-based compared to supervised training. Our findings suggest that CCT is associated with cognitive benefits in PD, including when delivered remotely. Larger, well-powered trials are warranted to examine what specific CCT regimens are most likely to promote cognitive and everyday functioning in the long-term.     

Multiple cognitive capabilities/deficits in children with an autism spectrum disorder: "weak" central coherence and its relationship to theory of mind and executive control

This study examined the validity of "weak" central coherence (CC) in the context of multiple cognitive capabilities/deficits in autism. Children with an autism spectrum disorder (ASD) and matched typically developing children were administered tasks tapping visuospatial coherence, false-belief understanding and aspects of executive control. Significant group differences were found in all three cognitive domains. Evidence of local processing on coherence tasks was widespread in the ASD group, but difficulties in attributing false beliefs and in components of executive functioning were present in fewer of the children with ASD. This cognitive profile was generally similar for younger and older children with ASD. Furthermore, weak CC was unrelated to false-belief understanding, but aspects of coherence (related to integration) were associated with aspects of executive control. Few associations were found between cognitive variables and indices of autistic symptomatology. Implications for CC theory are discussed.     

Effects of virtual reality combined cognitive and physical interventions on cognitive function in older adults with mild cognitive impairment: A systematic review and meta-analysis

ObjectiveCombined cognitive and physical interventions based on virtual reality may help delay the progression of MCI to dementia or prevent dementia. However, their efficacy is less well studied compared to pharmaceutical treatments. The purpose of this review was to evaluate the effects of cognitive and physical interventions based on virtual reality on cognitive function (global cognition, memory or executive function/attention) of older adults with mild cognitive impairment.MethodsWe searched the PubMed, Web of Science, Scopus, Embase, Cochrane Library, PsycINFO, CINAHL and IEEE from inception to 13 May 2021. Only randomized controlled trials which incorporated virtual reality cognitive and physical components targeted to individuals with mild cognitive impairment were eligible. Two researchers independently conducted document retrieval, study selection, data extraction, and methodological quality evaluation.Result7 randomized controlled trials were included in a total of 8 articles. No studies were rated as having a "high" risk of overall bias. The results of a meta-analysis showed that VR combined cognitive and physical interventions enhanced the global cognitive (MD = 2.66, 95% CI = 1.79–3.54, P = 0.03, I ² = 68%) abilities of older adults with mild cognitive impairment. The meta-analysis indicated that after virtual reality combined cognitive and physical interventions, effects on memory (SMD = −0.03, 95% CI = −0.60 to 0.55, P = 0.78, I ² = 0%) and executive function/attention (SMD = −0.19, 95% CI = −0.74 to 0.36, P = 0.09, I ² = 53%) were not statistically significant.ConclusionsThe present meta-analysis verifies the potential rehabilitative effects of virtual reality combined cognitive and physical interventions for older adults with mild cognitive impairment. More research is also needed to determine the optimal intensity and timing of interventions in the future.     

Cognitive profiles of mild cognitive impairment with and without vascular disease

This study examined whether the cognitive profile of subjects with mild cognitive impairment (MCI) with vascular disease differs from that of MCI subjects with no vascular disease. Consecutive MCI subjects with vascular disease (n=60) and matched MCI subjects with no vascular disease (n=60) were included in the study and were compared with healthy control subjects (n=60). The neuropsychological assessment comprised tests of speed and attention, episodic memory, visuospatial function, language, and executive function. Control subjects performed significantly better than did both MCI groups on the neuropsychological battery. MCI subjects with no vascular disease performed better overall than did MCI subjects with vascular disease, most clearly on tests of speed and attention, visuospatial function, and executive function. MCI subjects with and without vascular disease exhibited differences, both in terms of overall performance and of cognitive profiles. These differences can be largely explained by deficits in speed and attention and in executive function of the MCI subjects with vascular disease.     

A meta-analysis of cognitive deficits in euthymic patients with bipolar disorder

BACKGROUND: A number of studies have reported evidence of cognitive deficits in euthymic bipolar patients. Qualitative reviews of the literature have indicated impairments in executive functions and declarative memory are most consistently reported. However, not all primary studies conducted to date have had sufficient power to detect statistically significant differences and there have been few attempts to quantify the magnitude of impairments. This review aims to combine data from available studies to identify the profile of neuropsychological deficits in euthymic bipolar patients and quantify their magnitude. METHOD: Systematic literature review and meta-analysis. RESULTS: Large effect sizes (d>or=0.8) were noted for aspects of executive function (category fluency, mental manipulation) and verbal learning. Medium effect sizes (0.5相似文献   

Combined physical and cognitive training for older adults with and without cognitive impairment: A systematic review and network meta-analysis of randomized controlled trials

Combining physical exercise with cognitive training is a popular intervention in dementia prevention trials and guidelines. However, it remains unclear what combination strategies are most beneficial for cognitive and physical outcomes. We aimed to compare the efficacy of the three main types of combination strategies (simultaneous, sequential or exergaming) to either intervention alone or control in older adults. Randomized controlled trials of combined cognitive and physical training were included in multivariate and network meta-analyses. In cognitively healthy older adults and mild cognitive impairment, the effect of any combined intervention relative to control was small and statistically significant for overall cognitive (k = 41, Hedges’ g = 0.22, 95 % CI 0.14 to 0.30) and physical function (k = 32, g = 0.25, 95 % CI 0.13 to 0.37). Simultaneous training was the most efficacious approach for cognition, followed by sequential combinations and cognitive training alone, and significantly better than physical exercise. For physical outcomes, simultaneous and sequential training showed comparable efficacy as exercise alone and significantly exceeded all other control conditions. Exergaming ranked low for both outcomes. Our findings suggest that simultaneously and sequentially combined interventions are efficacious for promoting cognitive alongside physical health in older adults, and therefore should be preferred over implementation of single-domain training.     

Successful computer-assisted cognitive remediation therapy in patients with unipolar depression: a proof of principle study

BACKGROUND: Despite increasing awareness of the extent and severity of cognitive deficits in major depressive disorder (MDD), trials of cognitive remediation have not been conducted. We conducted a 10-week course of cognitive remediation in patients with long-term MDD to probe whether deficits in four targeted cognitive domains, (i) memory, (ii) attention, (iii) executive functioning and (iv) psychomotor speed, could be improved by this intervention. METHOD: We administered a computerized cognitive retraining package (PSSCogReHab) with demonstrated efficacy to 12 stable patients with recurrent MDD. Twelve matched patients with MDD and a group of healthy control participants were included for comparison; neither comparator group received the intervention that involved stimulation of cognitive functions through targeted, repetitive exercises in each domain. RESULTS: Patients who received cognitive training improved on a range of neuropsychological tests targeting attention, verbal learning and memory, psychomotor speed and executive function. This improvement exceeded that observed over the same time period in a group of matched comparisons. There was no change in depressive symptom scores over the course of the trial, thus improvement in cognitive performance occurred independent of other illness variables. CONCLUSIONS: These results provide preliminary evidence that improvement of cognitive functions through targeted, repetitive exercises is a viable method of cognitive remediation in patients with recurrent MDD.     

Everyday action in schizophrenia: performance patterns and underlying cognitive mechanisms

Everyday action is impaired among individuals with schizophrenia, yet few studies have characterized the nature of this deficit using performance-based measures. This study examined the performance of 20 individuals with schizophrenia or schizoaffective disorder on the Naturalistic Action Test (M. F. Schwartz, L. J. Buxbaum, M. Ferraro, T. Veramonti, & M. Segal, 2003). Performance was coded to examine overall impairment, task accomplishment, and error patterns and was compared with that of healthy controls (n = 28) and individuals with mild dementia (n = 23). Additionally, 2 competing accounts of everyday action deficits, the resource theory and an executive account, were evaluated. When compared with controls, the participants with schizophrenia demonstrated impaired performance. Relative to dementia patients, participants with schizophrenia obtained higher accomplishment scores but committed comparable rates of errors. Moreover, distributions of error types for the 2 groups differed, with the participants with schizophrenia demonstrating greater proportions of errors associated with executive dysfunction. This is the 1st study to show different Naturalistic Action Test performance patterns between 2 neurologically impaired populations. The distinct performance pattern demonstrated by individuals with schizophrenia reflects specific deficits in executive function.     

The effects of aerobic exercise and transcranial direct current stimulation on cognitive function in older adults with and without cognitive impairment: A systematic review and meta-analysis

BackgroundAerobic exercise (AE) may slow age-related cognitive decline. However, such cognition-sparing effects are not uniform across cognitive domains and studies. Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation and is also emerging as a potential alternative to pharmaceutical therapies. Like AE, the effectiveness of tDCS is also inconsistent for reducing cognitive impairment in ageing. The unexplored possibility exists that pairing AE and tDCS could produce synergistic effects and reciprocally augment cognition-improving effects in older individuals with and without cognitive impairments.Previous research found such synergistic effects on cognition when cognitive training is paired with tDCS in older individuals with and without mild cognitive impairment (MCI) or dementia.AimThe purpose of this systematic review with meta-analysis was to explore if pairing AE with tDCS could augment singular effects of AE and tDCS on global cognition (GC), working memory (WM) and executive function (EF) in older individuals with or without MCI and dementia.MethodsUsing a PRISMA-based systematic review, we compiled studies that examined the effects of AE alone, tDCS alone, and AE and tDCS combined on cognitive function in older individuals with and without mild cognitive impairment (MCI) or dementia. Using a PICOS approach, we systematically searched PubMed, Scopus and Web of Science searches up to December 2021, we focused on ‘MoCA’, ‘MMSE’, ‘Mini-Cog’ (measures) and ‘cognition’, ‘cognitive function’, ‘cognitive’, ‘cognitive performance’, ‘executive function’, ‘executive process’, ‘attention’, ‘memory’, ‘memory performance’ (outcome terms). We included only randomized controlled trials (RTC) in humans if available in English full text over the past 20 years, with participants’ age over 60. We assessed the methodological quality of the included studies (RTC) by the Physiotherapy Evidence Database (PEDro) scale.ResultsOverall, 68 studies were included in the meta-analyses. AE (ES = 0.56 [95% CI: 0.28–0.83], p = 0.01) and tDCS (ES = 0.69 [95% CI: 0.12–1.26], p = 0.02) improved GC in all three groups of older adults combined (healthy, MCI, demented). In healthy population, AE improved GC (ES = 0.46 [95% CI: 0.22–0.69], p = 0.01) and EF (ES = 0.27 [95% CI: 0.05–0.49], p = 0.02). AE improved GC in older adults with MCI (ES = 0.76 [95% CI: 0.21–1.32], p = 0.01). tDCS improved GC (ES = 0.69 [90% CI: 0.12–1.26], p = 0.02), all three cognitive function (GC, WM and EF) combined in older adults with dementia (ES = 1.12 [95% CI: 0.04–2.19], p = 0.04) and improved cognitive function in older adults overall (ES = 0.69 [95% CI: 0.20–1,18], p = 0.01).ConclusionOur systematic review with meta-analysis provided evidence that beyond the cardiovascular and fitness benefits of AE, pairing AE with tDCS may have the potential to slow symptom progression of cognitive decline in MCI and dementia. Future studies will examine the hypothesis of this present review that a potentiating effect would incrementally improve cognition with increasing severity of cognitive impairment.     

Emotion understanding and theory of mind among maltreated children in foster care: evidence of deficits

Children in foster care are at heightened risk for poor psychosocial outcomes. This study examined differences in two areas that may be associated with many of these outcomes, emotion understanding and theory of mind, using a sample of 3- to 5-year-old maltreated foster children (n = 60) and a comparison group of same-aged, low-income, nonmaltreated children living with their biological families (n = 31). Being in foster care was significantly associated with worse emotion understanding and theory of mind capabilities, even when accounting for age, intelligence, and executive function. There were no significant associations between length of time in foster care, number of transitions, and emotion understanding and theory of mind. Results help to expand knowledge about the cognitive and affective deficits of children in foster care and suggest that interventions targeted at these deficits include an emphasis on emotion understanding and theory of mind.     

Cognitive interventions in healthy older adults and people with mild cognitive impairment: A systematic review

Given that the research area of cognitive intervention studies in the aging population is growing rapidly, it is important to review and gauge more recent intervention studies, in order to determine the evidence for the effectiveness of cognitive interventions. The purpose of the present review was to update the recent systematic reviews of Papp et al. (2009) and Martin et al. (2011), to evaluate the effectiveness of cognitive interventions in healthy older adults and people with MCI, by taking into account the methodological quality of the interventions studies. A systematic review of randomized controlled trials (RCT) and clinical studies published between August 2007 and February 2012 in Pubmed and PsychINFO was performed. The quality of the included RCTs was assessed according to the CONSORT criteria for RCTs. A total of thirty-five studies were included; twenty-seven RTCs and eight clinical studies. The content of the intervention studies differed widely, as did the methodological quality of the included RCTs, but was considerably low with an average of 44% of the Consort items included. The results show evidence that cognitive training can be effective in improving various aspects of objective cognitive functioning; memory performance, executive functioning, processing speed, attention, fluid intelligence, and subjective cognitive performance. However, the issue whether the effects of cognitive interventions generalize to improvement in everyday life activities is still unresolved and needs to be addressed more explicitly in future research.     

The association between neuropsychological impairment, self-perceived cognitive deficits, fatigue and health related quality of life in breast cancer survivors following standard adjuvant versus high-dose chemotherapy

OBJECTIVE: The possible association between neuropsychological impairment, self-perceived cognitive deficits, fatigue and health related quality of life has been studied in high-risk breast cancer survivors 5 years following standard adjuvant (n=23) versus high-dose chemotherapy (n=24) and in early-stage breast cancer patients (n=29) (comparison group) following radiation therapy. METHODS: A neuropsychological assessment covering attention, memory and executive functions was used together with the questionnaire for self-perceived deficits in attention (FEDA), the multidimensional fatigue inventory (MFI-20) and the EORTC-QLQ-C30. RESULTS: Findings have shown that neuropsychological impairment is not directly associated with self-perceived cognitive deficits, fatigue and HRQOL. However, 46% of patients reported self-perceived cognitive deficits and 82% of the patients complained about cancer related fatigue. Except for reduced activity we did not find significant group differences, even though patients who received standard-dose chemotherapy had consistently higher levels of self-perceived cognitive deficits and fatigue, and the lowest HRQOL. CONCLUSION: Results emphasize the need for psychosocial counseling and support during treatment phase and follow up care as well. Sensitive cancer-specific measures for the assessment of self-perceived cognitive deficits in different cognitive domains according to neuropsychological measurements are required. PRACTICE IMPLICATIONS: The role of self-perceived cognitive deficits and fatigue should be considered in educational interventions and counseling. Specific rehabilitation measures should be developed, implemented and evaluated in order to meet the needs of these patients and to decrease the frequency of cognitive deficits following cancer treatment.     

Efficacy of lifestyle and psychosocial interventions in reducing cognitive decline in older people: Systematic review

It is unclear what non-pharmacological interventions to prevent cognitive decline should comprise. We systematically reviewed lifestyle and psychosocial interventions that aimed to reduce cognitive decline in healthy people aged 50+, and people of any age with Subjective Cognitive Decline or Mild Cognitive Impairment. We narratively synthesised evidence, prioritising results from studies rated as at lower Risk of Bias (ROB) and assigning Centre for Evidence Based Medicine grades. We included 64 papers, describing: psychosocial (n = 12), multi-domain (n = 10), exercise (n = 36), and dietary (n = 6) interventions. We found Grade A evidence that over 4+ months: aerobic exercise twice weekly had a moderate effect on global cognition in people with/ without MCI; and interventions that integrate cognitive and motor challenges (e.g. dance, dumb bell training) had small to moderate effects on memory or global cognition in people with MCI. We found Grade B evidence that 4+ months of creative art or story-telling groups in people with MCI; 6 months of resistance training in people with MCI and a two-year, dietary, exercise, cognitive training and social intervention in people with or without MCI had small, positive effects on global cognition. Effects for some intervention remained up to a year beyond facilitated sessions.     

Tobacco and marijuana use among adolescents and young adults: a systematic review of their co-use

Tobacco (TOB) and marijuana (MJ) are the most widely used drugs among adolescents and young adults. The literature on their co-use, however, has not been systematically reviewed. We identified 163 English language articles published from 1999 to 2009 examining TOB and MJ co-use, correlates or consequences of co-use, or interventions for prevention or cessation of co-use with participants aging 13-25 years. Most studies (n=114, 70%) examined TOB and MJ co-use, and 85% of relationships studied indicated a significant association. Fifty-nine studies (36%) examined correlates or consequences of co-use. Factors consistently associated with increased likelihood of co-use, defined as significant associations in at least four studies, were African-American ethnicity, mental and physical health characteristics (e.g., high-intensity pleasure temperament), and school characteristics (e.g., good grades). The only consistent consequence of co-use was exacerbation of mental health symptoms. Few studies examined prevention (n=3) or cessation (n=2) interventions for TOB and MJ co-use, and the findings were stronger for prevention efforts. A sufficient literature base has documented that TOB and MJ use are strongly related in young people, yet few consistent correlates and consequences of co-use have been identified to inform intervention targets.     

Ecological Assessment of Executive Function in Traumatic Brain Injury

Executive dysfunction is a common outcome in children who have sustained traumatic brain injury (TBI). Appropriate assessment of these complex interrelated regulatory functions is critical to plan for the necessary interventions yet present a challenge to our traditional methodologies. Ecological validity has become an increasingly important focus in neuropsychological assessment with particular relevance for the executive functions, which coordinate one's cognitive and behavioral capacities with real-world demand situations. The Behavior Rating Inventory of Executive Function (BRIEF) was developed to capture the real-world behavioral manifestations of executive dysfunction. Its development and various forms of validity, including ecological validity, are described. Application of the BRIEF's methodology to the assessment of executive dysfunction in TBI is provided. We advocate a multilevel approach to understanding executive function outcome in TBI, including traditional test-based measures of executive function, real-world behavioral manifestation of executive dysfunction, and the environmental system factors that impact the child. In this model, ecologically valid assessment of executive dysfunction provides an important bridge toward understanding the impact of component-level (i.e., test-based) deficits on the child's everyday adaptive functioning, which can assist the definition of targets for intervention.