ORCID Profile
0000-0002-8747-5118
Current Organisation
University of North Carolina at Chapel Hill
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Elsevier BV
Date: 07-2010
DOI: 10.1016/J.NEUROIMAGE.2010.02.017
Abstract: Frontostriatal circuit mediated cognitive dysfunction has been implicated in frontotemporal lobar degeneration (FTLD), but not Alzheimer's disease, or healthy aging. We measured the neostriatum (caudate nucleus and putamen) volume in FTLD (n=34), in comparison with controls (n=27) and Alzheimer's disease (AD, n=19) subjects. Diagnoses were based on international consensus criteria. Manual bilateral segmentation of the caudate nucleus and putamen was conducted blind to diagnosis by a single analyst, on MRI scans using a standardized protocol. Intra-cranial volume was calculated via a stereological point counting technique and was used for scaling the shape analysis. The manual segmentation binaries were analyzed using UNC Shape Analysis tools (University of North Carolina) to perform comparisons among FTLD, AD, and controls for global shape, local p-value significance maps, and mean magnitude of shape displacement. Shape analysis revealed that there was significant shape difference between FTLD, AD, and controls, consistent with the predicted frontostriatal dysfunction and of significant magnitude, as measured by displacement maps. There was a lateralized difference in shape for the left caudate for FTLD compared to AD non-specific global atrophy in AD compared to controls while FTLD showed a more specific pattern in regions relaying fronto- and corticostriatal circuits. Shape analysis shows regional specificity of atrophy, manifest as shape deflation, with implications for frontostriatal and corticostriatal motoric circuits, in FTLD, AD, and controls.
Publisher: Elsevier BV
Date: 11-2011
Publisher: Elsevier BV
Date: 2013
DOI: 10.1016/J.SCHRES.2012.10.040
Abstract: Abnormalities in hippoc al morphology are characteristic of schizophrenia and have also been reported in chronic cannabis users. There is a paucity of research investigating potential additive effects of cannabis use on brain pathology associated with schizophrenia. In this study, we performed hippoc al shape analysis in cannabis-using and non-using patients with schizophrenia, healthy cannabis users and healthy non-using controls. Hippoc al shape changes were observed in each group relative to controls, with the greatest degree of alterations (i.e., deflations across the hippoc us, and with an anterior predisposition), in cannabis-using schizophrenia patients. These alterations were associated with cannabis use patterns and psychotic symptoms.
Publisher: SAGE Publications
Date: 24-02-2012
Abstract: Objective: The caudate nucleus (CN) is a crucial component of the ventral striatum, which is part of a prefrontal-striatal-thalamic circuit that is modulated by limbic structures to subserve emotional processing. Bipolar disorder is thought to be underpinned by dysfunctional anterior limbic networks, although MRI studies examining the CN have shown equivocal results. As gross volumetric analyses may not detect subtle regional change, we aimed to clarify the role of the CN in bipolar disorder by undertaking shape analysis to detect regional reductions. Methods: The CN was manually traced on MRI scans from 27 patients with bipolar-I disorder and 24 matched controls. A non-parametric spherical harmonic shape analysis was undertaken using the SPHARM toolkit. Results: Whilst the left CN volume was consistently larger in the s le, there was no effect of group or gender or significant interactions between these variables. Volume did not correlate with illness duration or lithium dosage, but was larger in those with a history of psychosis at trend level. However, left caudate shape differed significantly between groups, with deflation in an area along the ventromedial surface (connecting to dorsolateral prefrontal regions) in bipolar patients. Psychotic patients showed increases in the dorsal head and body at trend level overall, in regions connecting to medial and orbitofrontal regions. Conclusions: These findings suggest that subtle rather than gross structural changes occur in the CN, which may not be detectable by volumetric analysis alone, and reflect alterations in specific frontostriatal circuitry in the disorder.
Publisher: Elsevier BV
Date: 2015
Publisher: Elsevier BV
Date: 04-2011
Publisher: Elsevier BV
Date: 02-2011
DOI: 10.1016/J.PSCYCHRESNS.2010.09.014
Abstract: Frontostriatal circuit mediated cognitive dysfunction has been implicated in frontotemporal lobar degeneration (FTLD) and may differ across subtypes of FTLD. We manually segmented the neostriatum (caudate nucleus and putamen) in FTLD subtypes: behavioral variant frontotemporal dementia, FTD, n=12 semantic dementia, SD, n=13 and progressive non-fluent aphasia, PNFA, n=9) in comparison with controls (n=27). Diagnoses were based on international consensus criteria. Manual bilateral segmentation of the caudate nucleus and putamen was conducted blind to diagnosis by a single analyst, on MRI scans using a standardized protocol. Intracranial volume was calculated via a stereological point counting technique and was used for normalizing the shape analysis. Segmented binaries were analyzed using the Spherical Harmonic (SPHARM) Shape Analysis tools (University of North Carolina) to perform comparisons between FTLD subtypes and controls for global shape difference, local significance maps and mean magnitude maps of shape displacement. Shape analysis revealed that there was significant shape difference between FTLD subtypes and controls, consistent with the predicted frontostriatal dysfunction and of significant magnitude, as measured by displacement maps. These differences were not significant for SD compared to controls lesser for PNFA compared to controls whilst FTD showed a more specific pattern in regions relaying fronto- and corticostriatal circuits. Shape analysis shows regional specificity of atrophy, manifest as shape deflation, with a differential between FTLD subtypes, compared to controls.
Location: United States of America
No related grants have been discovered for Martin Styner.