Department of Neurology Works
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Item Fulminant multiple sclerosis(American Society of Neuroradiology, 1992) Niebler, Gwendolyn; Harris, Todd; Davis, Tom; Roos, Karen; Neurology, School of MedicineItem Comparison of rhyming and word generation with FMRI(Wiley Open Access, 2000-06-06) Lurito, Joseph T.; Kareken, David A.; Lowe, Mark J.; Chen, Shen Hsing A.; Mathews, Vincent P.; Neurology, School of MedicineFunctional magnetic resonance imaging (FMRI) has been successfully used to non‐invasively map language function, but has several disadvantages. These include severe motion sensitivity, which limits overt verbal responses in behavioral paradigms, such as word generation. The lack of overt responses prevents behavioral validation, making data interpretation difficult. Our objective was to compare the FMRI activation patterns of a novel silent rhyme determination task requiring a non‐verbal response, to covert word generation from visually presented letters. Five strongly right‐handed subjects performed both tasks during multi‐slice coronal echo‐planar T2*–weighted FMRI. Single subject activation maps were generated for each task by correlation analysis of single pixel time series to a boxcar reference function. These maps for the two tasks were separately interpolated to 2563, transformed into Talairach space, summed, and thresholded at t>6. Combined activation maps from both tasks showed similar robust perisylvian language area activation, including inferior frontal gyrus, posterior superior temporal lobe, and fusiform gyrus. Subjects performed well on the rhyming task, which activated left hemisphere cortical regions more selectively than the word generation task. The rhyming task showed less activation than the word generation task in areas typically not considered specifically related to language function, such as the dorsolateral prefrontal cortex and anterior cingulate. The rhyming task is a useful tool for brain mapping and clinical applications, potentially more specific to cortical language areas than verbal fluency.Item Depression and Stroke: Cause or Consequence?(2005) Williams, Linda S.Depression after stroke is common. Although different opinions exist about the definition, diagnosis, and measurement of outcomes related to depression after stroke, there is little debate about the prevalence of depression symptoms and their impact on stroke survivors and their families. Depression after stroke has long been recognized as a common condition with many negative effects in the poststroke period, but more recently depression has also been identified as an independent stroke risk factor. Given that there are at least 500,000 new ischemic strokes yearly in the United States, a conservative estimate is that 150,000 U.S. stroke survivors develop poststroke depression each year. Because effective treatments exist but are likely underutilized for depression, this is an important example of an evidence-practice gap to which increased efforts to improve care should be made. Such efforts would likely improve not only patient symptoms but may also decrease stroke risk, influence stroke functional recovery, decrease mortality, and reduce poststroke health care utilization. This article provides an overview of depression diagnosis in stroke, reviews the epidemiology of poststroke depression and its associated morbidity and mortality, and reviews existing evidence on the treatment and prevention of poststroke depression.Item Involvement of the left anterior insula and frontopolar gyrus in odor discrimination(Wiley, 2006-11-06) Plailly, Jane; Radnovich, Alexander J.; Sabri, Merav; Royet, Jean-Pierre; Kareken, David A.; Neurology, School of MedicineDiscriminating between successively presented odors requires brief storage of the first odor's perceptual trace, which then needs to be subsequently compared to the second odor in the pair. This study explores the cortical areas involved in odor discrimination and compares them with findings from studies of working‐memory, traditionally investigated with n‐back paradigms. Sixteen right‐handed subjects underwent H2 15O positron emission tomography during counterbalanced conditions of odorless sniffing, repeated single odor detection, multiple odor detection, and conscious successive discrimination between odor pairs. Eight odorants were delivered using a computer‐controlled olfactometer through a birhinal nasal cannula. Conscious successive odor discrimination evoked significantly greater activity in the left anterior insula and frontopolar gyrus when compared to reported sensory detection of the identical odors. Additional activation was found in the left lateral orbital/inferior frontal and middle frontal gyri when discrimination was compared to the odorless condition. The left anterior insula is likely involved in the evaluation of odor properties. Consistent with other studies, frontopolar and middle frontal gyrus activation is more likely related to working memory during odor discrimination.Item Post-Stroke Depression: Focus on Diagnosis and Management during Stroke Rehabilitation(2007-09) Johnson, Elizabeth A; Bakas, Tamilyn; Williams, Linda S.Post-Stroke Depression: Focus on Diagnosis and Management during Stroke Rehabilitation. Geriatrics & Aging. 10(8):492–6.Item Perinatal stroke and the risk of developing childhood epilepsy(2007-10) Golomb, Meredith R.; Garg, Bhuwan P; Carvalho, Karen S; Johnson, Cynthia S; Williams, Linda S.Objectives—To describe the prevalence of epilepsy after 6 months-of-age in children with perinatal stroke and examine whether perinatal data predict epilepsy onset and resolution. Study design—A retrospective review of 64 children with perinatal stroke. In children with at least 6 months of follow-up data, Kaplan-Meier curves, univariate log-rank tests, and Cox proportional hazards models were used to examine predictors of time to development of seizures, and time to resolution of seizures in children with epilepsy. The association of risk factors with the presence of epilepsy at any time after 6 months-of-age was examined using Fisher’s exact test. Results—Forty-one of the 61 children with at least 6 months of follow-up data (67%) had epilepsy between 6 months-of-age and last follow-up, but in 13 of 41 seizures eventually resolved and anticonvulsants were discontinued. Infarct on prenatal ultrasound (p=0.0065) and family history of epilepsy (p=0.0093) were significantly associated with time to development of seizures after 6 months-of-age in the univariate analysis. No assessed variables were associated with time to resolution of epilepsy or with the presence of epilepsy after 6 months-of-age. Conclusions—Childhood epilepsy is frequent after perinatal stroke. Evidence of infarction on prenatal ultrasound and a family history of epilepsy predict earlier onset of active seizures.Item The Association of Cerebral Palsy with Other Disability in Children with Perinatal Arterial Ischemic Stroke(2007-10) Golomb, Meredith R.; Saha, Chandan; Garg, Bhuwan P; Azzouz, Faouzi; Williams, Linda S.The association of cerebral palsy with other disabilities in children with perinatal stroke has not been well-studied. We examined this association in 111 children with perinatal stroke: 67 with neonatal presentation, and 44 with delayed presentation. Seventy-six children (68%) had cerebral palsy, which was hemiplegic in 66 and tri- or quadriplegic in 10. Fifty-five (72%) children with cerebral palsy had at least one other disability: 45 (59%) had a cognitive/speech impairment (moderate-severe in 20), and 36 (47%) had epilepsy (moderate-severe in 11). In children with neonatal presentation, cerebral palsy was associated with epilepsy (P = 0.0076) and cognitive impairment (P = 0.0001). These associations could not be tested in children with delayed presentation because almost all children in this group had cerebral palsy. In another analysis with multivariate logistic regression for children with cerebral palsy, children who had both neonatal presentation and history of cesarean-section delivery were more likely to have epilepsy (P = 0.001). Children with cerebral palsy after perinatal stroke who had neonatal presentation were more likely to have severe cognitive impairment (odds ratio, 7.78; 95% confidence interval, 1.80-47.32) or severe epilepsy (odds ratio, 6.64; 95% confidence interval, 1.21-69.21) than children with delayed presentation. Children with cerebral palsy after perinatal stroke are likely to have an additional disability; those with neonatal presentation are more likely to have a severe disability.Item Drugs of Abuse Can Entrain Circadian Rhythms(Hindawi Publishing Corporation, 2007-11-02) Kosobud, Ann E.K.; Gillman, Andrea G.; Leffel, Joseph K., II; Pecoraro, Norman C.; Rebec, G.V.; Timberlake, William; Neurology, School of MedicineCircadian rhythms prepare organisms for predictable events during the Earth's 24-h day. These rhythms are entrained by a variety of stimuli. Light is the most ubiquitous and best known zeitgeber, but a number of others have been identified, including food, social cues, locomotor activity, and, most recently drugs of abuse. Given the diversity of zeitgebers, it is probably not surprising that genes capable of clock functions are located throughout almost all organs and tissues. Recent evidence suggests that drugs of abuse can directly entrain some circadian rhythms. We have report here that entrainment by drugs of abuse is independent of the suprachiasmatic nucleus and the light/dark cycle, is not dependent on direct locomotor stimulation, and is shared by a variety of classes of drugs of abuse. We suggest that drug-entrained rhythms reflect variations in underlying neurophysiological states. This could be the basis for known daily variations in drug metabolism, tolerance, and sensitivity to drug reward. These rhythms could also take the form of daily periods of increased motivation to seek and take drugs, and thus contribute to abuse, addiction and relapse.Item Geographic variation in poststroke depression among veterans with acute stroke(2008) Jia, Huanguang; Ried, L Douglas; Wang, Xinping; Damush, Teresa M.; Young, Linda J; Cameon, Randi H; Williams, Linda S.This study compared patterns of poststroke depression (PSD) detection among veterans with acute stroke in eight U.S. geographic regions. Department of Veterans Affairs (VA) medical and pharmacy data as well as Medicare data were used. International Classification of Diseases-9th Revision depression codes and antidepressant medication dispensing were applied to define patients’ PSD status 12 months poststroke. Logistic regression models were fit to compare VA PSD diagnosis and overall PSD detection between the regions. The use of VA medical data alone may underestimate the rate of PSD. Geographic variation in PSD detection depended on the data used. If VA medical data alone were used, we found no significant variation. If VA medical data were used along with Medicare and VA pharmacy data, we observed a significant variation in overall PSD detection across the regions after adjusting for potential risk factors. VA clinicians and policy makers need to consider enrollees’ use of services outside the system when conducting program evaluation. Future research on PSD among veteran patients should use VA medical data in combination with Medicare and VA pharmacy data to obtain a comprehensive understanding of patients’ PSD.Item Prevention of secondary stroke in VA: Role of occupational therapists and physical therapists(2008) Schmid, Arlene A.; Butterbaugh, Lisa; Egolf, Courtney; Richards, Virginia; Williams, Linda S.Occupational therapists (OTs) and physical therapists (PTs) have the opportunity and obligation to advocate secondary stroke prevention via health promotion (HP) behaviors. This prospective survey of Department of Veterans Affairs (VA) OTs and PTs determined whether they know about VA stroke rehabilitation guidelines and whether they integrate secondary stroke prevention into poststroke rehabilitation care. Questions revolved around knowledge of VA guidelines, inclusion of stroke risk-factor modification, and HP education to patients. Thirty-four surveys (45%) were returned from six facilities. Participants included 12 OTs and 22 PTs. Half (53%) of the therapists were aware of the VA guidelines and nearly half (48%) provided HP activities to patients; PTs were significantly more likely to do so than OTs (p = 0.02). Half of the queried therapists were unaware of the VA guidelines; increasing therapists’ education about the guidelines and the necessity of HP and secondary stroke prevention may reduce veterans’ risk of a second stroke. Because many stroke risk factors are modifiable and stroke survivors spend a great deal of time with the rehabilitation therapist, OTs and PTs can and should provide such education to reduce the risk of a second stroke.