81 research outputs found
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FMRI investigation of cross-cultural music comprehension.
The popular view of music as a "universal" language ignores the privileged position of the cultural insider in comprehending musical information unique to their own tradition. The purpose of this study was to test the hypothesis that listeners would demonstrate different neural activity in response to culturally familiar and unfamiliar music and that those differences may be affected by the extent of subjects' formal musical training. Just as familiar languages have been shown to use distinct brain processes, we hypothesized that an analogous difference might be found in music and that it may depend in part on subjects' formal musical knowledge. Using fMRI we compared the activation patterns of professional musicians and untrained controls reared in the United States as they listened to music from their culture (Western) and from an unfamiliar culture (Chinese). No overall differences in activation were observed for either subject group in response to the two musical styles, although there were differences in recall performance based on style and there were activation differences based on training. Trained listeners demonstrated additional activation in the right STG for both musics and in the right and left midfrontal regions for Western music and Chinese music, respectively. Our findings indicate that listening to culturally different musics may activate similar neural resources but with dissimilar results in recall performance
Vessel target location estimation during the TIPS procedure
Creation of a Transjugular Intrahepatic Portosystemic Shunt (TIPS) requires passage of a needle toward a moving target that is only seen transiently by x-ray prior to needle passage. Intraoperative, 3D target localization would facilitate target access and improve the safety of the procedure. The clinical assumption is that patients undergoing the TIPS procedure possess rigid, cirrhotic livers that undergo only intraoperative translation without significant deformation or rotation. Based upon this assumption, we hypothesize that the position of any unseen, 3D target point within the liver can be determined intraoperatively by precalculation of the relative positions of the target point to a different 3D point that can be tracked intraoperatively. This paper examines this hypothesis using intraoperatively acquired, biplane, x-ray images of 7 patients. In 6, we tracked the effects of cardiac and respiratory motion, and in 3 the effects of needle pressure. Methods involved reconstruction of 3D vessel bifurcation and other trackable intrahepatic points from biplane angiograms, measurement of liver deformation by examining changing distances between these 3D points over time, and comparison of expected to actual displacements of these points with respect to a fixed reference point in the liver. We conclude that, for the rigid livers associated with patients undergoing TIPS, that there is less intraoperative deformation than previously reported by other groups addressing healthy liver deformation, and that the location of an unseen target can be predicted within 3 mm accuracy
Functional magnetic resonance imaging outcomes from a comprehensive magnetic resonance study of children with fetal alcohol spectrum disorders
A comprehensive neuropsychological/psychiatric, MR imaging, (MRI), MR spectroscopy (MRS), and functional MRI (fMRI) assessment was administered to children with fetal alcohol spectrum disorders (FASD) to determine if global and/or focal abnormalities could be identified, and distinguish diagnostic subclassifications across the spectrum. The four study groups included: 1. FAS/Partial FAS; 2. Static Encephalopathy/Alcohol Exposed (SE/AE); 3. Neurobehavioral Disorder/Alcohol Exposed (ND/AE); and 4. healthy peers with no prenatal alcohol exposure. fMRI outcomes are reported here. The neuropsychological/psychiatric, MRI, and MRS outcomes are reported separately. fMRI was used to assess activation in seven brain regions during performance of N-back working memory tasks. Children across the full spectrum of FASD exhibited significant working memory deficits and altered activation patterns in brain regions that are known to be involved in working memory. These results demonstrate the potential research and diagnostic value of this non-invasive MR tool in the field of FASD
LipoproteinâAssociated Phospholipase A2 Activity Is a Marker of Risk But Not a Useful Target for Treatment in Patients With Stable Coronary Heart Disease
Background: We evaluated lipoproteinâassociated phospholipase A2 (LpâPLA2) activity in patients with stable coronary heart disease before and during treatment with darapladib, a selective LpâPLA2 inhibitor, in relation to outcomes and the effects of darapladib in the STABILITY trial. Methods and Results: Plasma LpâPLA2 activity was determined at baseline (n=14 500); at 1 month (n=13 709); serially (n=100) at 3, 6, and 18 months; and at the end of treatment. Adjusted Cox regression models evaluated associations between LpâPLA2 activity levels and outcomes. At baseline, the median LpâPLA2 level was 172.4 ÎŒmol/min per liter (interquartile range 143.1â204.2 ÎŒmol/min per liter). Comparing the highest and lowest LpâPLA2 quartile groups, the hazard ratios were 1.50 (95% CI 1.23â1.82) for the primary composite end point (cardiovascular death, myocardial infarction, or stroke), 1.95 (95% CI 1.29â2.93) for hospitalization for heart failure, 1.42 (1.07â1.89) for cardiovascular death, and 1.37 (1.03â1.81) for myocardial infarction after adjustment for baseline characteristics, standard laboratory variables, and other prognostic biomarkers. Treatment with darapladib led to a â65% persistent reduction in median LpâPLA2 activity. There were no associations between onâtreatment LpâPLA2 activity or changes of LpâPLA2 activity and outcomes, and there were no significant interactions between baseline and onâtreatment LpâPLA2 activity or changes in LpâPLA2 activity levels and the effects of darapladib on outcomes. Conclusions: Although high LpâPLA2 activity was associated with increased risk of cardiovascular events, pharmacological lowering of LpâPLA2 activity by â65% did not significantly reduce cardiovascular events in patients with stable coronary heart disease, regardless of the baseline level or the magnitude of change of LpâPLA2 activity
Clinical and biomarker changes in premanifest Huntington disease show trial feasibility: A decade of the PREDICT-HD study
There is growing consensus that intervention and treatment of Huntington disease (HD) should occur at the earliest stage possible. Various early-intervention methods for this fatal neurodegenerative disease have been identified, but preventive clinical trials for HD are limited by a lack of knowledge of the natural history of the disease and a dearth of appropriate outcome measures. Objectives of the current study are to document the natural history of premanifest HD progression in the largest cohort ever studied and to develop a battery of imaging and clinical markers of premanifest HD progression that can be used as outcome measures in preventive clinical trials. Neurobiological predictors of Huntingtonâs disease is a 32-site, international, observational study of premanifest HD, with annual examination of 1013 participants with premanifest HD and 301 gene-expansion negative controls between 2001 and 2012. Findings document 39 variables representing imaging, motor, cognitive, functional, and psychiatric domains, showing different rates of decline between premanifest HD and controls. Required sample size and models of premanifest HD are presented to inform future design of clinical and preclinical research. Preventive clinical trials in premanifest HD with participants who have a medium or high probability of motor onset are calculated to be as resource-effective as those conducted in diagnosed HD and could interrupt disease 7â12years earlier. Methods and measures for preventive clinical trials in premanifest HD more than a dozen years from motor onset are also feasible. These findings represent the most thorough documentation of a clinical battery for experimental therapeutics in stages of premanifest HD, the time period for which effective intervention may provide the most positive possible outcome for patients and their families affected by this devastating disease
Regional atrophy associated with cognitive and motor function in prodromal Huntington disease.
Contrast Masking and Differential fMRI Brain Responses Relative to a Rest Condition
Analysis of an fMRI protocol often involves a comparison of the fMRI brain signal between task A (e.g., zero-back working memory task) and task B (e.g., 2-back working memory). When a third reference condition such as fixation is included then comparisons between the main tasks and this reference are also possible (e.g. 2-back versus fixation). In this case, the fMRI signal from each voxelâs response with regard to fixation can be classified into one of six possible response patterns (1), three for A > B (both A and B > fixation; both A and B < fixation; A > fixation > B) and three for B > A.
The objective of this project was to develop a method to separately map these six different fMRI brain response patterns in addition to the standard task A versus task B comparisons. Understanding the relationship between activation for each task in comparison to fixation is especially important when evaluating response to intervention in fMRI studies
Recommended from our members
FMRI investigation of cross-cultural music comprehension.
The popular view of music as a "universal" language ignores the privileged position of the cultural insider in comprehending musical information unique to their own tradition. The purpose of this study was to test the hypothesis that listeners would demonstrate different neural activity in response to culturally familiar and unfamiliar music and that those differences may be affected by the extent of subjects' formal musical training. Just as familiar languages have been shown to use distinct brain processes, we hypothesized that an analogous difference might be found in music and that it may depend in part on subjects' formal musical knowledge. Using fMRI we compared the activation patterns of professional musicians and untrained controls reared in the United States as they listened to music from their culture (Western) and from an unfamiliar culture (Chinese). No overall differences in activation were observed for either subject group in response to the two musical styles, although there were differences in recall performance based on style and there were activation differences based on training. Trained listeners demonstrated additional activation in the right STG for both musics and in the right and left midfrontal regions for Western music and Chinese music, respectively. Our findings indicate that listening to culturally different musics may activate similar neural resources but with dissimilar results in recall performance
CT measurement of suprasellar cistern predicts rate of cognitive decline in Alzheimer's disease
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