A Diffusion Tensor Magnetic Resonance Imaging Study of Frontal Cortex Connections in Very-Late-Onset Schizophrenia-Like Psychosis

Jones, Derek K.; Catani, Marco; Pierpaoli, Carlo; Reeves, Suzanne; Shergill, Sukhwinder S.; O’Sullivan, Michael; Maguire, Philip; Horsfield, Mark A.; Simmons, Andrew; Williams, Steven; Howard, Robert

doi:10.1097/00019442-200512000-00009

Cited by 73 publications

(24 citation statements)

References 48 publications

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“…A prior history of substance use among patients should also be noted as a possible limitation, although post-hoc analyses did not identify any effect of substance abuse/dependence on the observed FA reductions. Lastly, it should be acknowledged that several studies (Jones et al, 2005;Voineskos et al, 2010) reported that elderly patients with schizophrenia do not differ from healthy volunteers on some measures of white matter integrity, including those investigated in the current study. Thus, despite prior antipsychotic medication exposure, some patients may be resistant to the effects described in the current study.…”

Section: Discussionmentioning

confidence: 61%

White Matter Changes Associated with Antipsychotic Treatment in First-Episode Psychosis

Szeszko

Robinson

Ikuta

et al. 2013

Neuropsychopharmacol

117

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Second-generation antipsychotics are utilized extensively in the treatment of psychotic disorders and other psychiatric conditions, but the effects of these medications on human brain white matter are not well understood. We thus investigated the effects of secondgeneration antipsychotics on white matter integrity using tract-based spatial statistics in patients experiencing a first episode of psychosis with little or no prior antipsychotic exposure, and how potential changes were associated with metabolic side effects. Thirty-five (26 men/9 women) patients experiencing a first episode of psychosis received diffusion tensor imaging (DTI) exams, clinical assessments, and provided fasting blood samples at the onset of antipsychotic treatment, and then again after 12 weeks of treatment with either risperidone or aripiprazole in a double-blind randomized clinical trial. In addition, 35 (26 men/9 women) healthy volunteers received DTI exams at a baseline time point and then after 12 weeks. Patients demonstrated significant (po0.05; family-wise error corrected) fractional anisotropy reductions within the parietal and occipital white matter following antipsychotic treatment. Greater overall fractional anisotropy reduction was significantly correlated with greater increases in low-density lipoprotein. There were no significant fractional anisotropy increases among patients following treatment. Moreover, healthy volunteers did not demonstrate either significant increases or decreases in fractional anisotropy across a comparable 12-week interval. The use of antipsychotics may be associated with a subtle loss of white matter integrity that is related to greater side effects, thus raising potentially important considerations regarding risk/benefit in their usage. Limitations of the current study, however, include a prior history of substance use among patients and our inability to exclude the possibility of disease progression.

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Section: Discussionmentioning

confidence: 61%

White Matter Changes Associated with Antipsychotic Treatment in First-Episode Psychosis

Szeszko

Robinson

Ikuta

et al. 2013

Neuropsychopharmacol

117

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“…Briefly, measurements were obtained using 3Dslicer and diffusion tensor streamline tractography. In order to ensure precise segmentation of the structure, we used a multiple ROI method (e.g., Catani et al, 2002; Jones et al, 2005). Eight separate Regions of Interest (ROIs) were manually defined, by the same rater (JF), blind to diagnosis, in order to tract the desired fibers, as described in Fitzsimmons et al (2009).…”

Section: Methodsmentioning

confidence: 99%

Diffusion tensor imaging study of the fornix in first episode schizophrenia and in healthy controls

Fitzsimmons

Hamoda

Swisher

et al. 2014

Schizophrenia Research

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Background The fornix is a compact bundle of white matter fibers that project from the hippocampus to the mamillary bodies and septal nuclei. Its association with memory, as well as with symptoms in schizophrenia, has been reported in chronic schizophrenia. The purpose of this study is to determine whether or not fornix abnormalities are evident at the onset of schizophrenia. Methods Diffusion Tensor Imaging (DTI) and DT tractography were used to evaluate the fornix in 21 patients with first episode schizophrenia (16 males/5 females) and 22 healthy controls (13 males/9 females). Groups were matched on age, gender, parental socioeconomic status, education and handedness. Fractional anisotropy (FA), a measure of white matter integrity, radial diffusivity (RD), thought to reflect myelin integrity, trace, a possible marker of atrophy or cell loss, and axial diffusivity (AD), thought to reflect axonal integrity, were averaged over the entire tract extracted by means of DT tractography, and used to investigate fornix abnormalities in first episode schizophrenia compared with healthy controls. Results Significant group differences were found between first episode patients and controls for FA (p=0.0001), RD (p=0.001) and trace (p= 0.006). Conclusion These findings suggest abnormalities in the fornix in the early stages of schizophrenia, and further suggest that white matter abnormalities, which are apparent in the early course of the disease, may reflect myelin disturbances.

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“…Stopping criteria for fiber tracking included a low FA (0.15) and a rapid change of direction (20° per 1 mm; used in Jones et al, 2005). The next step included fiber extraction, which was done with previously defined ROIs.…”

Section: Methodsmentioning

confidence: 99%

Neuropsychological disturbance in schizophrenia: A diffusion tensor imaging study.

Nestor¹,

Kubicki²,

Niznikiewicz³

et al. 2008

Neuropsychology

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Patients with schizophrenia and healthy control subjects underwent both neuropsychological evaluation and magnetic resonance diffusion tensor imaging, during which the cingulum bundle (CB) and the uncinate fasciculus (UF) were defined with fiber tractography and their integrity was quantified. On the basis of prior findings, it was hypothesized that neuropsychological disturbance in schizophrenia may be characterized, in part, by 2 dissociable functional neuroanatomical relationships: (a) executive functioning-CB integrity and (b) episodic memory-UF integrity. In support of the hypothesis, hierarchical regression results indicated that reduced white matter of the CB and the UF differentially and specifically predicted deficits in executive functioning and memory, respectively. Neuropsychological correlates of the CB also extended to lower generalized intelligence, as well as to reduced visual memory that may be related to failures of contextual monitoring of to-be-remembered scenes. Reduced white matter of the CB and the UF may each make distinct contributions to neuropsychological disturbance in schizophrenia.Correspondence concerning this article should be addressed to Paul G. Nestor, Department of Psychology, University of Massachusetts, Boston, MA 02125-3393. paul.nestor@umb.edu. NIH Public Access Author ManuscriptNeuropsychology. Author manuscript; available in PMC 2009 December 10. Published in final edited form as:Neuropsychology. & Kahn, 1999;Heinrichs, 2005;Heinrichs & Zakzanis, 1998;McKenna, 1991;O'Carroll, 2000;Saykin et al., 1994;Weinberger, Berman, & Zec, 1986). Although typically occurring against a backdrop of generalized cognitive impairment, disease-related deficits in episodic memory for events encoded in time and place can be dissociated from disruptions in executive functions that serve to guide action and thought (Nestor et al., 2004). These neuropsychological deficits may also each involve different pathophysiology, as twin studies have strongly implicated genetic factors in executive dysfunction, whereas nongenetic influences may preferentially impact memory disturbance (Cannon et al., 2000).As the "primary expression of the schizophrenic brain" (Heinrichs, 2005, p. 229), neuropsychological disturbances of memory and executive functions have increasingly been theorized to reflect sequelae not of focal brain abnormalities but of pathological connectivity among brain regions (Andreasen et al., 1999;McGlashan & Hoffman, 2000;Nestor et al., 1998Nestor et al., , 2004Stephan, Baldeweg, & Friston, 2006;Weinberger, Berman, Suddath, & Torrey, 1992;Winterer, Coppola, Egan, Goldberg, & Weinberger, 2003). Wernicke (1906) first ascribed a central role in the expression of schizophrenia to anatomical abnormalities of association fiber tracts traveling between frontal and temporal lobes. More recently, neuroimaging findings that showed abnormal functional connectivity in schizophrenia have echoed Wernicke's seminal, generative idea of disease-related disruption in the functional integration of ...

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A Diffusion Tensor Magnetic Resonance Imaging Study of Frontal Cortex Connections in Very-Late-Onset Schizophrenia-Like Psychosis

Cited by 73 publications

References 48 publications

White Matter Changes Associated with Antipsychotic Treatment in First-Episode Psychosis

White Matter Changes Associated with Antipsychotic Treatment in First-Episode Psychosis

Diffusion tensor imaging study of the fornix in first episode schizophrenia and in healthy controls

Neuropsychological disturbance in schizophrenia: A diffusion tensor imaging study.

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