Tom A. Schweizer

Rehabilitation of Executive Functioning in Patients with Frontal Lobe Brain Damage with Goal Management Training

Executive functioning deficits due to brain disease affecting frontal lobe functions cause significant real-life disability, yet solid evidence in support of executive functioning interventions is lacking. Goal Management Training (GMT), an executive functioning intervention that draws upon theories concerning goal processing and sustained attention, has received empirical support in studies of patients with traumatic brain injury, normal aging, and case studies. GMT promotes a mindful approach to complex real-life tasks that pose problems for patients with executive functioning deficits, with a main goal of periodically stopping ongoing behavior to monitor and adjust goals. In this controlled trial, an expanded version of GMT was compared to an alternative intervention, Brain Health Workshop that was matched to GMT on non-specific characteristics that can affect intervention outcome. Participants included 19 individuals in the chronic phase of recovery from brain disease (predominantly stroke) affecting frontal lobe function. Outcome data indicated specific effects of GMT on the Sustained Attention to Response Task as well as the Tower Test, a visuospatial problem-solving measure that reflected far transfer of training effects. There were no significant effects on self-report questionnaires, likely owing to the complexity of these measures in this heterogeneous patient sample. Overall, these data support the efficacy of GMT in the rehabilitation of executive functioning deficits.

Neuropsychological Profile of Acute Alcohol Intoxication during Ascending and Descending Blood Alcohol Concentrations

Numerous studies have investigated the effects of alcohol on motor processes during rising and declining blood alcohol concentrations (BAC), however, relatively little research has examined the alcohol-induced impairment of cognitive performance on the two limbs of the BAC curve. This experiment administered a neuropsychological test battery to assess the degree to which rising and declining BACs during an acute dose of alcohol impair nine cognitive processes within an individual. In all, 20 healthy male social drinkers (university students) were assigned to one of two groups (n=10) who received a beverage containing either 0.0 g/kg (placebo) or 0.65 g/kg alcohol and performed the test battery when BAC was increasing and was decreasing. Comparisons of alcohol and placebo groups revealed impairment (slower response and/or increased errors) in seven of the cognitive processes: long-term verbal memory; information processing; declarative memory; inhibitory control; short-term visual memory; long-term visual memory, and visual-spatial working memory. However, some processes were impaired only during rising BACs whereas the impairment of others during declining BACs was evident only by an increase in errors. These results show cognitive tasks performed by an individual are not similarly affected by rising and declining BACs, and call attention to the importance of assessing both speed and accuracy on both limbs of the BAC curve. The particular cognitive processes differentially affected by rising vs declining BACs raised the possibility that acute alcohol intoxication may impair one cerebral hemisphere to a greater degree than the other, and this could be explored by neuroimaging techniques.

Rehabilitation of Executive Functioning After Focal Damage to the Cerebellum

Executive dysfunction accounts for significant disability in patients with many types of brain injury in many locations. Clinical reports have described impaired executive functioning after damage to the cerebellum, and anatomical and neuroimaging studies have identified the likely basis for this effect: a cortico—ponto—cerebellar network through which the cerebellum is densely connected to areas of frontal cortex. The patterns of executive impairment attributable to cerebellar damage have been extensively described in the past 15 years, but there has been no assessment of the efficacy of rehabilitation in this patient population. Here, the use of a cognitive rehabilitation technique, Goal Management Training, in a patient with persisting executive dysfunction after a right cerebellar hemorrhage is described. The patient made and maintained modest gains on measures of sustained attention, planning, and organization that translated into significant improvement in real-life functioning. This is the first report on the rehabilitation of impaired executive functioning following focal damage to the cerebellum and in the presence of intact frontal cortex.

Mini-Mental State Examination versus Montreal Cognitive Assessment: Rapid assessment tools for cognitive and functional outcome after aneurysmal subarachnoid hemorrhage

OBJECTIVE Recent studies suggest that the Montreal Cognitive Assessment (MoCA) is more sensitive to stroke-associated cognitive dysfunction than the Mini-Mental State Examination (MMSE), but little is known about how these screening measures relate to neurocognitive test performance or real-world functioning in patients with good recovery after aneurysmal subarachnoid hemorrhage (aSAH). The aim of the present study was to determine how MoCA and MMSE scores relate to neurocognitive impairment and return to work after aSAH. METHODS Thirty-two patients with aSAH who had made a good recovery completed the MoCA, the MMSE, and a battery of neurocognitive tests. RESULTS 42% and 0% of aSAH patients were impaired on the MoCA and MMSE, respectively. The MoCA had acceptable sensitivity (40-100%) and specificity (54-68%) (Table 3). The MMSE failed to detect impairment in any cognitive domain. The MoCA, but not the MMSE, predicted performance on tests of verbal learning, executive function, working memory, visuospatial function, and motor function. Superior performance on the Animal naming and Abstraction subtests of the MoCA score were associated with return to work following aSAH. CONCLUSION Compared to the MMSE, the MoCA is more sensitive to aSAH-associated cognitive impairment. Certain MoCA subtests are also sensitive to functional difficulties after aSAH such as return to work. These findings support the utility of the MoCA as a brief bedside assessment of cognitive and real-world outcome in aSAH survivors.

Brain activity during driving with distraction: an immersive fMRI study

Introduction: Non-invasive measurements of brain activity have an important role to play in understanding driving ability. The current study aimed to identify the neural underpinnings of human driving behavior by visualizing the areas of the brain involved in driving under different levels of demand, such as driving while distracted or making left turns at busy intersections. Materials and Methods: To capture brain activity during driving, we placed a driving simulator with a fully functional steering wheel and pedals in a 3.0 Tesla functional magnetic resonance imaging (fMRI) system. To identify the brain areas involved while performing different real-world driving maneuvers, participants completed tasks ranging from simple (right turns) to more complex (left turns at busy intersections). To assess the effects of driving while distracted, participants were asked to perform an auditory task while driving analogous to speaking on a hands-free device and driving. Results: A widely distributed brain network was identified, especially when making left turns at busy intersections compared to more simple driving tasks. During distracted driving, brain activation shifted dramatically from the posterior, visual and spatial areas to the prefrontal cortex. Conclusions: Our findings suggest that the distracted brain sacrificed areas in the posterior brain important for visual attention and alertness to recruit enough brain resources to perform a secondary, cognitive task. The present findings offer important new insights into the scientific understanding of the neuro-cognitive mechanisms of driving behavior and lay down an important foundation for future clinical research.

Subarachnoid Hemorrhage International Trialists Data Repository (SAHIT)

The outcome of patients with aneurysmal subarachnoid hemorrhage (SAH) has improved slowly over the past 25 years. This improvement may be due to early aneurysm repair by endovascular or open means, use of nimodipine, and better critical care management. Despite this improvement, mortality remains at about 40%, and many survivors have permanent neurologic, cognitive, and neuropsychologic deficits. Randomized clinical trials have tested pharmacologic therapies, but few have been successful. There are numerous explanations for the failure of these trials, including ineffective interventions, inadequate sample size, treatment side effects, and insensitive or inappropriate outcome measures. Outcome often is evaluated on a good-bad dichotomous scale that was developed for traumatic brain injury 40 years ago. To address these issues, we established the Subarachnoid Hemorrhage International Trialists (SAHIT) data repository. The primary aim of the SAHIT data repository is to provide a unique resource for prognostic analysis and for studies aimed at optimizing the design and analysis of phase III trials in aneurysmal SAH. With this aim in mind, we convened a multinational investigator meeting to explore merging individual patient data from multiple clinical trials and observational databases of patients with SAH and to create an agreement under which such a group of investigators could submit data and collaborate. We welcome collaboration with other investigators.

Web-Based Intervention Programs for Depression: A Scoping Review and Evaluation

Background Although depression is known to affect millions of people worldwide, individuals seeking aid from qualified health care professionals are faced with a number of barriers to treatment including a lack of treatment resources, limited number of qualified service providers, stigma associated with diagnosis and treatment, prolonged wait times, cost, and barriers to accessibility such as transportation and clinic locations. The delivery of depression interventions through the Internet may provide a practical solution to addressing some of these barriers. Objective The purpose of this scoping review was to answer the following questions: (1) What Web-delivered programs are currently available that offer an interactive treatment component for depression?, (2) What are the contents, accessibility, and usability of each identified program?, and (3) What tools, supports, and research evidence are available for each identified program? Methods Using the popular search engines Google, Yahoo, and Bing (Canadian platforms), two reviewers independently searched for interactive Web-based interventions targeting the treatment of depression. The Beacon website, an information portal for online health applications, was also consulted. For each identified program, accessibility, usability, tools, support, and research evidence were evaluated and programs were categorized as evidence-based versus non-evidence-based if they had been the subject of at least one randomized controlled trial. Programs were scored using a 28-point rating system, and evidence- versus non-evidence-based programs were compared and contrasted. Although this review included all programs meeting exclusion and inclusion criteria found using the described search method, only English language Web-delivered depression programs were awarded an evaluation score. Results The review identified 32 programs meeting inclusion criteria. There was a great deal of variability among the programs captured in this evaluation. Many of the programs were developed for general adolescent or adult audiences, with few (n=2) focusing on special populations (eg, military personnel, older adults). Cognitive behavioral therapy was the most common therapeutic approach used in the programs described. Program interactive components included mood assessments and supplementary homework sheets such as activity planning and goal setting. Only 12 of the programs had published evidence in support of their efficacy and treatment of depressive symptoms. Conclusions There are a number of interactive depression interventions available through the Internet. Recommendations for future programs, or the adaptation of existing programs include offering a greater selection of alternative languages, removing registration restrictions, free trial periods for programs requiring user fees, and amending programs to meet the needs of special populations (eg, those with cognitive and/or visual impairments). Furthermore, discussion of specific and relevant topics to the target audience while also enhancing overall user control would contribute to a more accessible intervention tool.

Lateralized Cerebellar Contributions to Word Generation: A Phonemic and Semantic Fluency Study

Impairment on verbal fluency tasks has been one of the more consistently reported neuropsychological findings after cerebellar lesions, but it has not been uniformly observed and the possible underlying cognitive basis has not been investigated. We tested twenty-two patients with chronic, unilateral cerebellar lesions (12 Left, 10 Right) and thirty controls on phonemic and semantic fluency tasks. We measured total words produced, words produced in the initial 15 seconds, errors and strategy switches. In the phonemic fluency task, the right cerebellar lesion (RC) group produced significantly fewer words compared to the left cerebellar lesion (LC) group and healthy controls, particularly over the first 15 seconds of the task with no increase in errors and significantly fewer switches over the entire task. In the semantic fluency task there was only a modest decrease in total words in the RC group compared to controls. RC lesions impair fluency with many of the same performance characteristics as left prefrontal lesions. This supports the hypotheses of a prefrontal-lateral cerebellar system for modulation of attention/executive or strategy demanding tasks.

Neurocognitive profiles in older adults with and without major depression

To delineate the differences between older persons with and without a diagnosis of major depression.

Neurobiology of Delusions in Alzheimer’s Disease

Alzheimer’s disease (AD) is associated with cognitive and functional impairment as well as neuropsychiatric sequelae, including psychotic symptoms such as delusions and hallucinations. Strong evidence supports the need to study delusions separate from hallucinations. Integrating the epidemiology, clinical correlates, and neuropathological and genetic literature for delusions in AD allows us to speculate on etiology and mechanisms. Plaque and tangle deposition in individuals with susceptible alleles of serotonergic, muscarinic, nicotinic, or Apoε4 genes appears to result in disruption of cortical circuitry, culminating in delusions. While delusions in AD correspond to a phenotype distinct from AD without delusions, subtypes of delusions may also define further distinct clinical entities. Persecutory delusions may occur earlier in the illness and have a more significant genetic component than misidentification delusions, which are associated with increased cognitive impairment and advanced dementia. Clearly distinguishing between these two syndromes is essential to making progress in the area of delusions in AD.