Faculty Bibliography

Traumatic brain injury often negatively impacts episodic memory; however, studies of the neural substrates of this impairment have been limited. In this study, both encoding and recognition of visually presented stimuli were examined with functional magnetic resonance imaging. Twelve adults with chronic complicated mild, moderate, and severe injuries were compared with a matched group of 12 controls. Behavioral task performance did not differentiate the groups. During neuroimaging, however, the group of individuals with traumatic brain injury exhibited increased activation, as well as increased bilaterality and dispersion as compared to controls. Findings are discussed in terms of increased resource recruitment.

Traumatic brain injury (TBI) is a major cause of death and disability. In the United States alone approximately 1.4 million sustain a TBI each year, of which 50,000 people die, and over 200,000 are hospitalized. Despite numerous prior clinical trials no standard pharmacotherapy for the treatment of TBI has been established. Citicoline, a naturally occurring endogenous compound, offers the potential of neuroprotection, neurorecovery, and neurofacilitation to enhance recovery after TBI. Citicoline has a favorable side-effect profile in humans and several meta-analyses suggest a benefit of citicoline treatment in stroke and dementia. COBRIT is a randomized, double-blind, placebo-controlled, multi-center trial of the effects of 90 days of citicoline on functional outcome in patients with complicated mild, moderate, and severe TBI. In all, 1292 patients will be recruited over an estimated 32 months from eight clinical sites with random assignment to citicoline (1000 mg twice a day) or placebo (twice a day), administered enterally or orally. Functional outcomes are assessed at 30, 90, and 180 days after the day of randomization. The primary outcome consists of a set of measures that will be analyzed as a composite measure using a global test procedure at 90 days. The measures comprise the following core battery: the California Verbal Learning Test II; the Controlled Oral Word Association Test; Digit Span; Extended Glasgow Outcome Scale; the Processing Speed Index; Stroop Test part 1 and Stroop Test part 2; and Trail Making Test parts A and B. Secondary outcomes include survival, toxicity, and rate of recovery.

This article presents four case studies of rehabilitation science programs that have created enduring research efforts: one in physical therapy, one in interdisciplinary rehabilitation sciences, and two in physical medicine and rehabilitation. Several themes emerge from these case studies. First, building an enduring research program takes time and significant foundational work. Most importantly, it is crucial to have the support of the dean, academic institution, and medical center. This seems to be a prerequisite for success in this area.

OBJECTIVE: To examine the predictive validity of a brief neuropsychologic test battery consisting of the Galveston Orientation and Amnesia Test, the California Verbal Learning Test-II, Trail-Making Test (TMT), Symbol Digit Modalities Test, grooved pegboard, phonemic and categorical word generation tasks, the Wechsler Test of Adult Reading (WTAR), and the Wisconsin Card Sorting Test-64 relative to functional outcome at 1 year in persons with traumatic brain injury. DESIGN: Inception cohort study. Follow-up period of 12 months. SETTING: Seven Traumatic Brain Injury Model System centers. Neuropsychologic testing was conducted during the acute inpatient rehabilitation stay and functional outcome measures were obtained at 1-year outpatient follow-up. PARTICIPANTS: Adults (N=174) who met criteria for admission to inpatient brain injury rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: FIM instrument, Disability Rating Scale, Supervision Rating Scale, Satisfaction With Life Scale (SWLS), and Glasgow Outcome Scale-Extended. RESULTS: Multiple regression analyses revealed that performance on the neuropsychologic test battery was predictive of outcome at 1 year postinjury for all outcome measures, except FIM motor scores and the SWLS. Cognitive performance using this battery was found to predict 1-year outcomes above and beyond functional variables and injury severity variables collected during inpatient rehabilitation, thereby indicating incremental validity for this test battery. Individual tests that were found to be significant predictors of 1-year outcomes included the WTAR and TMT part B. CONCLUSIONS: These findings support the clinical utility and ecological validity of this battery with respect to level of disability, functional independence, and supervision required.

OBJECTIVES: To determine (1) if more than 50% of patients with moderate to severe traumatic brain injury (TBI) who met study criteria can complete a battery of neuropsychologic tests in less than 75 minutes 2 to 6 weeks after injury regardless of posttraumatic amnesia (PTA) status; (2) which tests are most likely to be completed; and (3) range of scores obtained. DESIGN: Prospective multicenter observational study. SETTING: Acute inpatient neurorehabilitation hospitals. PARTICIPANTS: Screened 543 Traumatic Brain Injury Model System patients with moderate to severe TBI; 354 were tested at 2 to 6 weeks postinjury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Percentage of patients able to complete the neuropsychologic tests in less than 75 minutes. RESULTS: Two hundred eighteen (62%) patients completed the battery in 66 minutes on average. Mean interval from injury to testing was 28.3+/-7.1 days. Tests completed with the highest frequency were California Verbal Learning Test-II, FAS, and animal naming. Performance was less impaired (P<.001) on all measures for patients who had emerged from PTA. CONCLUSIONS: Approximately two thirds of screened patients were able to complete a brief neuropsychologic test battery at 2 to 6 weeks postinjury, regardless of PTA status. Although patients out of PTA were less impaired on all test measures, confusion did not preclude participation in the test battery or prohibit assignment of test scores. Early neuropsychologic assessment after TBI is feasible even for many patients who are still in PTA.

Functional Near-Infrared Spectroscopy (fNIRS) is a neuroimaging technique that utilizes light in the near-infrared spectrum (between 700 and 1000 nm) to detect hemodynamic changes within the cortex when sensory, motor, or cognitive activation occurs. FNIRS principles have been used to study brain oxygenation for several decades, but have more recently been applied to study cognitive processes. This paper provides a description of basic fNIRS techniques, and provides a review of the rehabilitation-related literature. The authors discuss strengths and weaknesses of this technique, assert that fNIRS may be particularly beneficial to neurorehabilitation of cognitive disabilities, and suggest future applications.

This randomized clinical trial utilized established techniques to improve new learning and memory performance in multiple sclerosis (MS) participants with learning impairment. Participants were 29 individuals with clinically definite MS with documented learning deficits, randomly assigned to the experimental or control group. The experimental group underwent eight sessions of the Story Memory Technique (SMT), while the control group participated in eight sessions of memory exercises. Neuropsychological assessment was conducted at baseline, immediately following treatment and 5 weeks later to assess outcome. When stratifying participants by degree of learning deficits, a significant treatment effect was noted. MS participants with moderate-severe impairment in learning showed a significant improvement in learning abilities when compared to controls, (t(19) =3.32, P<0.01) evident in 88% of participants in the experimental group. Little improvement was noted in MS participants with mild learning impairments. Significant self-reported improvements in memory were noted in MS participants that underwent treatment, but not those that did not undergo treatment (t(26) =2.55, P<0.01). Results indicate that learning and memory deficits in MS can be effectively treated through a memory rehabilitation program utilizing context and imagery to improve new learning. Appropriate patient selection is important, with moderately-severely impaired individuals showing significantly greater benefit from treatment.

Working memory deficits are common in Multi Sclerosis (MS) and have been identified behaviourally in numerous studies. Despite recent advance in functional magnetic resonance imaging (fMRI), few published studies have examined cerebral activations associated with working memory dysfunction in MS. The present study examines brain activation patterns during performance of a working memory task in individual with clinically definite MS, compared to healthy controls (HC). fMRI was performed using a 1.5 Tesla GE scanner during a modified Paced Auditory Serial Addition Test (mPA-SAT). Participants were 6 individuals with MS with working memory impairment as evidenced on neuropsychological testing, 5 individuals with MS without working memory impairment, and 5 HC. Groups were demographically equivalent. Data were analyzed using Statistical Parametric Mapping (SPM99) software, with a stringent significance level (alpha < .005, voxel extent > or =8). Both MS groups and the HC group were able to perform the task, with comparable performance in terms of numbers of correct responses. Activation patterns within the HC and MS not-impaired groups were noted in similar brain regions, consistent with published observations in healthy samples That is, activations were lateralized to the left hemisphere, involving predominantly frontal regions. In contrast, the MS impaired group showed greater right frontal and right parietal lobe activation, when compared with the HC group. Thus, it appears that working memory dysfunction in MS is associated with altered patterns of cerebral activation that are related to the presence of cognitive impairement, and not solely a function of MS.