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Background Suicide is the second leading cause of death in all youth and among adults with bipolar disorder (BD). The risk of suicide in BD is among the highest of all psychiatric conditions. Self-harm, including suicide attempts and non-suicidal self-injury, is a leading risk factor for suicide. Neuroimaging studies suggest reward circuits are implicated in both BD and self-harm; however, studies have yet to examine self-harm related resting-state functional connectivity (rsFC) phenotypes within adolescent BD. Methods Resting-state fMRI data were analyzed for 141 adolescents, ages 13–20 years, including 38 with BD and lifetime self-harm (BDSH+), 33 with BD and no self-harm (BDSH−), and 70 healthy controls (HC). The dorsolateral prefrontal cortex (dlPFC), orbitofrontal cortex (OFC) and amygdala were examined as regions of interest in seed-to-voxel analyses. A general linear model was used to explore the bivariate correlations for each seed. Results BDSH− had increased positive rsFC between the left amygdala and left lateral occipital cortex, and between the right dlPFC and right frontal pole, and increased negative rsFC between the left amygdala and left superior frontal gyrus compared to BDSH+ and HC. BDSH+ had increased positive rsFC of the right OFC with the precuneus and left paracingulate gyrus compared to BDSH− and HC. Conclusions This study provides preliminary evidence of altered reward-related rsFC in relation to self-harm in adolescents with BD. Between-group differences conveyed a combination of putative risk and resilience connectivity patterns. Future studies are warranted to evaluate changes in rsFC in response to treatment and related changes in self-harm.

The areas of driving impairment characteristic of mild cognitive impairment (MCI) remain unclear. This study compared the simulated driving performance of 24 individuals with MCI, including amnestic single-domain (sd-MCI, n = 11) and amnestic multiple-domain MCI (md-MCI, n = 13), and 20 age-matched controls. Individuals with MCI committed over twice as many driving errors (20.0 versus 9.9), demonstrated difficulty with lane maintenance, and committed more errors during left turns with traffic compared to healthy controls. Specifically, individuals with md-MCI demonstrated greater driving difficulty compared to healthy controls, relative to those with sd-MCI. Differentiating between different subtypes of MCI may be important when evaluating driving safety.

Importance: The clock-drawing test (CDT) is an important neurocognitive assessment tool, widely used as a screening test for dementia. Behavioral performance on the test has been studied extensively, but there is scant literature on the underlying neural correlates.Purpose: To administer the CDT naturalistically to a healthy older aging population in an MRI environment, and characterize the brain activity associated with test completion.Main Outcome and Measure: Blood-oxygen-level dependent (BOLD) functional MRI was conducted as participants completed the CDT using novel tablet technology. Brain activity during CDT performance was contrasted to rest periods of visual fixation. Performance on the CDT was evaluated using a standardized scoring system (Rouleau score) and time to test completion. To assess convergent validity, performance during fMRI was compared to performance on a standard paper version of the task, administered in a psychometric testing room.Results: Study findings are reported for 33 cognitively healthy older participants aged 52–85. Activation was observed in the bilateral frontal, occipital and parietal lobes as well as the supplementary motor area and precentral gyri. Increased age was significantly correlated with Rouleau scores on the clock number drawing (R2) component (rho = -0.55, p < 0.001); the clock hand drawing (R3) component (rho = -0.50, p < 0.005); and the total clock (rho = -0.62, p < 0.001). Increased age was also associated with decreased activity in the bilateral parietal and occipital lobes as well as the right temporal lobe and right motor areas.Conclusion and Relevance: This imaging study characterizes the brain activity underlying performance of the CDT in a healthy older aging population using the most naturalistic version of the task to date. The results suggest that the functions of the occipital and parietal lobe are significantly altered by the normal aging process, which may lead to performance decrements.

Mild cognitive impairment (MCI) can affect multiple cognitive abilities, leading to difficulty in performing complex, cognitively demanding daily tasks, such as driving. This study combined driving simulation and functional magnetic resonance imaging (fMRI) to investigate brain function in individuals with MCI while they performed a car-following task. The behavioral driving performance of 24 patients with MCI and 20 healthy age-matched controls was compared during a simulated car-following task. Functional brain connectivity during driving was analyzed for a separate cohort of 15 patients with MCI and 15 controls. Individuals with MCI had minor difficulty with lane maintenance, exhibiting significantly increased variability in steering compared to controls. Patients with MCI also exhibited reduced connectivity between fronto-parietal regions, as well as between regions involved in cognitive control (medial frontal cortex) and regions important for visual processing (cuneus, angular gyrus, superior occipital cortex, inferior and superior parietal cortex). Greater difficulty in lane maintenance (i.e., increased steering variability and lane deviations) among individuals with MCI was further associated with increased connectivity between the posterior cingulate cortex (PCC) and inferior frontal gyrus, as well as increased intra-cerebellar connectivity. Thus, compared to cognitively healthy controls, patients with MCI showed reduced connectivity between regions involved in visual attention, visual processing, cognitive control, and performance monitoring. Greater difficulty with lane maintenance among patients with MCI may reflect failure to inhibit components of the default-mode network (PCC), leading to interference with task-relevant networks as well as alterations in cerebellum connectivity.

BackgroundStroke can affect a variety of cognitive, perceptual, and motor abilities that are important for safe driving. Results of studies assessing post-stroke driving ability are quite variable in the areas and degree of driving impairment among patients. This highlights the need to consider clinical characteristics, including stroke subtype, when assessing driving performance.MethodsWe compared the simulated driving performance of 30 chronic stroke patients (>3 months), including 15 patients with ischemic stroke (IS) and 15 patients with subarachnoid hemorrhage (SAH), and 20 age-matched controls. A preliminary analysis was performed, subdividing IS patients into right (n = 8) and left (n = 6) hemispheric lesions and SAH patients into middle cerebral artery (MCA, n = 5) and anterior communicating artery (n = 6) territory. A secondary analysis was conducted to investigate the cognitive correlates of driving.ResultsNine patients (30%) exhibited impaired simulated driving performance, including four patients with IS (26.7%) and five patients with SAH (33.3%). Both patients with IS (2.3 vs. 0.3, U = 76, p 0.6, p

The purpose of the study is to determine driving habits and behaviors of patients with brain tumors in order to better inform discussions around driving safety in this population. Eight-four patients with brain tumors participated in a survey on their driving behaviors since their diagnosis. Thirteen of these patients and thirteen sex- and age-matched healthy controls participated in cognitive testing and several driving simulation scenarios in order to objectively assess driving performance. Survey responses demonstrated that patients with brain tumors engage in a variety of driving scenarios with little subjectve difficulty. On the driving simulation tasks, patients and healthy controls performed similarly except that patients had more speed exceedances (U = 41, p

The cerebellum, which is important for movement control and planning, is often affected by many neurological conditions. Until now there has been limited information regarding how the function of the cerebellum impacts driving ability. This study used fMRI with an integrated virtual reality driving simulator to determine which aspects of driving performance are related to the cerebellum in healthy drivers (Experiment 1). It also investigated drivers with focal cerebellar lesions to identify how damage to this brain region impairs driving abilities. The results showed that cerebellar functioning is responsible for motor-speed coordination and complex temporal-motor integration necessary to execute driving behaviours. As predicted, drivers with cerebellar damage, showed significantly compromised speed control during basic driving conditions, whereas their ability to perform during interactive driving situations was preserved. New insights into neural mechanisms and brain plasticity regarding driving behaviour are discussed. Strategies in assessing and rehabilitating drivers with related neurological conditions are provided.

BACKGROUND: Many individuals with Alzheimer's disease (AD) and mild cognitive impairment (MCI) are at an increased risk of driving impairment. There is a need for tools with sufficient validity to help clinicians assess driving ability. OBJECTIVE: Provide a systematic review and meta-analysis of the primary driving assessment methods (on-road, cognitive, driving simulation assessments) in patients with MCI and AD. METHODS: We investigated (1) the predictive utility of cognitive tests and domains, and (2) the areas and degree of driving impairment in patients with MCI and AD. Effect sizes of were derived and analyzed in a random effects model. RESULTS: Thirty-two articles (including 1,293 AD patients, 92 MCI patients, 2,040 healthy older controls) met inclusion criteria. Driving outcomes included: On-road test scores, pass/fail classifications, errors; caregiver reports; real world crash involvement; and driving simulator collisions/risky behavior. Executive function (ES [95% CI]; 0.61 [0.41, 0.81]), attention (0.55 [0.33, 0.77]), visuospatial function (0.50 [0.34, 0.65]), and global cognition (0.61 [0.39, 0.83]) emerged as significant predictors of driving performance. Trail Making Test Part B (TMT-B, 0.61 [0.28, 0.94]), TMT-A (0.65 [0.08, 1.21]), and Maze test (0.88 [0.60, 1.15]) emerged as the best single predictors of driving performance. Patients with very mild AD (CDR = 0.5) mild AD (CDR = 1) were more likely to fail an on-road test than healthy control drivers (CDR = 0), with failure rates of 13.6%, 33.3% and 1.6%, respectively. CONCLUSION: The driving ability of patients with MCI and AD appears to be related to degree of cognitive impairment. Across studies, there are inconsistent cognitive predictors and reported driving outcomes in MCI and AD patients. Future large-scale studies should investigate the driving performance and associated neural networks of subgroups of AD (very mild, mild, moderate) and MCI (amnestic, non-amnestic, single-domain, multiple-domain). Language: en

Introduction: Guidelines recommend that patients refrain from driving in the acute phase of stroke. Patients are permitted to resume driving if no significant motor, cognitive, or perceptual deficits are present. This study investigated the driving performance of patients with mild ischemic stroke in the acute and chronic stages of recovery. It was hypothesized that patients with acute stroke would commit more risky driving errors (e.g. collisions, lane deviations) and that patients with chronic stroke would perform comparably to healthy matched controls. Methods: Driving simulator technology (STISIM) was used to compare the driving performance of 11 patients with acute mild ischemic stroke (NIHSS3 months post-stroke), and 11 healthy age- and education-matched controls. Participants completed a city-driving task and a car following task, which requires sustained attention and error monitoring. Results: Patients with acute stroke committed over three times as many risky driving errors compared to healthy controls during the city-driving task (6.2 vs. 1.7, p Conclusions: Results suggest that patients with acute mild ischemic stroke may demonstrate impaired driving ability and that performance may improve in the chronic phase of recovery. The results reinforce the importance of refraining from driving in the acute phase of stroke and suggest that patients with good functional and cognitive recovery may be safe to resume driving in the chronic phase of injury. A large-scale longitudinal study is required to determine the optimal time for patients to resume driving after stroke.

Introduction: It is well established that cognitive and functional impairments persist despite good clinical outcomes in patients who suffer aneurysmal subarachnoid hemorrhage (aSAH). The impact of these impairments on real-world tasks such as driving a motor vehicle is currently unclear. This study aimed to investigate driving ability of aSAH patients using a driving simulator. We hypothesized that patients would exhibit more driving errors during the most cognitively demanding aspects, particularly while executing left turns at busy intersections, where the driver must quickly integrate many complex and dynamic visual stimuli to make a rapid decision and turn safely. Methods: Nine functionally independent aSAH patients (>3 months post-ictus) and nine healthy control participants matched for age (patients: 58±13; controls: 59±14, p > 0.05) completed two driving scenarios (STISIM). The total number of errors committed and errors associated with intersections were compared between groups. Errors included collisions, speeding, centerline crossings, road edge excursions, stop signs missed and traffic light tickets. Results: The mean number of total errors did not differ between the patient and control groups (28 versus 22, p > 0.05); however, patients committed a greater number of hazardous errors, including collisions (2.4 versus 0.1, p < 0.05) and road edge excursions (3.7 versus 0.3, p < 0.01), than controls. Total errors at intersection turns were greater for patients (7.7 versus 3.2, p < 0.05). When stratified by type of turn, patients experienced more errors than controls during left turns (1.6 versus 0.2, p < 0.01) and left turns with oncoming traffic (2.3 versus 0.8, p < 0.05) but not during right turns (3.8 versus 2.2, p > 0.05). Conclusion: Our results suggest probable driving impairment in some aSAH patients during more difficult aspects of driving, such as making left turns at a busy intersection, which is where most real-world accidents occur. This analysis was limited by a small sample, and further research should explore the clinical and cognitive correlates of driving ability in a large sample of aSAH patients.

Driving is a complex activity that requires intact cognitive, behavioral, and motor function. Stroke is one of the most prevalent neurologic impairments and can affect all of these functions. However, diagnosis of stroke is not a definitive indicator of driving impairment. Determining fitness to drive after stroke is a very complex process and is typically based on cognitive assessments, on-road performance, simulator-based assessment, or a combination of the three. The aim of this review was to provide (1) a systematic review of the literature on cognitive, on-road, and simulator assessment after stroke, and (2) address the existing limitations and inconsistencies in stroke and driving research. Our results indicated that of 1413 total stroke patients, 748 definitively passed and 367 definitely failed an on-road assessment, with minimal information provided about clinical presentation. In addition, although the Stroke Driver Screening Assessment, the Useful Field of View Test, and the Rey-O Complex Figure test may have some utility in predicting driving performance, most cognitive measures have been inconsistently and minimally explored. Several limitations were observed across studies such as procedural inconsistencies, including outcome variables used (eg, driving cessation and pass/fail classification) and the heterogeneity of patient samples (eg, time since stroke and stroke location). Due, in part, to the larger variability in results of cognitive, on-road, and simulator-based assessment, there is no consensus regarding a valid and reliable driving assessment for physicians. Future studies should assess poststroke driving fitness by differentiating different stages, severities, and locations of stroke.