Progressive deterioration of thalamic nuclei relates to cortical network decline in schizophrenia.

Thalamic abnormalities are considered part of the complex pathophysiology of schizophrenia, particularly the involvement of specific thalamic nuclei. The goals of this study were to: introduce a novel atlas-based parcellation scheme for defining various thalamic nuclei; compare their integrity in a schizophrenia sample against healthy individuals at baseline and follow-up time points, as well as rates of change over time; examine relationships between the nuclei and abnormalities in known connected cortical regions; and finally, to determine if schizophrenia-related thalamic nuclei changes relate to cognitive functioning and clinical symptoms. Subjects were from a larger longitudinal 2-year follow-up study, schizophrenia (n=20) and healthy individuals (n=20) were group-matched for age, gender, and recent-alcohol use.

Anterior thalamic radiation integrity in schizophrenia: a diffusion-tensor imaging study.

The anterior limb of the internal capsule (ALIC) is a white matter structure, the medial portion of which includes the anterior thalamic radiation (ATR) carrying nerve fibers between thalamus and prefrontal cortex. ATR abnormalities have a possible link with cognitive abnormalities and negative symptoms in schizophrenia. We aimed to study the fiber integrity of the ATR more selectively by isolating the medial portion of the ALIC using region-of-interest based methodology.

Feasibility of geometric-intensity-based semi-automated delineation of the tentorium cerebelli from MRI scans.

This paper describes a feasibility study of a method for delineating the tentorium cerebelli in magnetic resonance imaging (MRI) brain scans. The tentorium cerebelli is a thin sheet of dura matter covering the cerebellum and separating it from the posterior part of the temporal lobe and the occipital lobe of the cerebral hemispheres. Cortical structures such as the parahippocampal gyrus can be indistinguishable from tentorium in magnetized prepared rapid gradient echo and T1-weighted MRI scans.

Progressive deformation of deep brain nuclei and hippocampal-amygdala formation in schizophrenia.

Background: Progressive decreases in cortical gray matter volume have been reported in schizophrenia. However, studies of progressive change in deep brain nuclei and hippocampal-amygdala formation have not yielded consistent findings.

Methods: Two high-resolution, T1-weighted magnetic resonance images were collected 2 years apart in 56 schizophrenia and 62 control subjects.

Abnormalities of cingulate gyrus neuroanatomy in schizophrenia.

Objective And Methods: Abnormalities of the neuroanatomy of the gray matter of the cingulate gyrus, especially its anterior segment, have been suggested to be an important characteristic of schizophrenia. In this study, T1-weighted magnetic resonance scans were collected in 53 individuals with schizophrenia and 68 comparison subjects matched for age, gender, race and parental socioeconomic status. We applied Labeled Cortical Mantle Distance Mapping to assess the volume, surface area and thickness of the cortical mantle within the anterior (AC) and posterior (PC) segments of the cingulate gyrus, excluding the paracingulate gyrus, and related these anatomical measures to measures of psychopathology and illness duration.

Inter-rater reliability of manual segmentation of the superior, inferior and middle frontal gyri.

Precise rules for locating the anatomical boundaries of the dorsolateral prefrontal cortex (DLPFC) or its subdivisions, i.e., superior, inferior and middle frontal gyri (SFG, IFG and MFG) on magnetic resonance images (MRI), have not been defined.

Structural analysis of the basal ganglia in schizophrenia.

Increases in the total volume of basal ganglia structures have been reported in schizophrenia. However, patterns of basal ganglia shape change, which can reveal localized changes in substructure volumes, have not been investigated. In this study, the total volume and shape of several basal ganglia structures were compared in subjects with and without schizophrenia.

Abnormalities of thalamic activation and cognition in schizophrenia.

Objective: Functional and structural magnetic resonance imaging (MRI) was used to investigate relationships among structure, functional activation, and cognitive deficits related to the thalamus in individuals with schizophrenia and healthy comparison subjects.

Method: Thirty-six schizophrenia subjects and 28 healthy comparison subjects matched by age, gender, race, and parental socioeconomic status underwent structural and functional MRI while performing a series of memory tasks, including an N-back task (working memory), intentional memorization of a series of pictures or words (episodic encoding), and a yes/no recognition task. Functional activation magnitudes in seven regions of interest within the thalamic complex, as defined by anatomical and functional criteria, were computed for each group.

Abnormalities of hippocampal surface structure in very mild dementia of the Alzheimer type.

To better define the pattern of hippocampal deformity early in the course of Alzheimer's disease, we compared the pattern of hippocampal surface variation in subjects with very mild dementia of the Alzheimer type (DAT) and nondemented subjects. The surface of the hippocampus was divided a priori on a neuroanatomical template into three zones approximating the locations of underlying subfields [Csernansky, J.G.

Correlations between antemortem hippocampal volume and postmortem neuropathology in AD subjects.

Antemortem measures of hippocampal volume have been used to distinguish subjects with and without probable Alzheimer disease (AD). However, relatively little information is available about how well such antemortem measures correlate with postmortem measures of disease in AD subjects. In this study, antemortem magnetic resonance scans were collected from 10 subjects with probable AD and 3 nondemented controls who later came to autopsy.

Changes in hippocampal volume and shape across time distinguish dementia of the Alzheimer type from healthy aging.

Rates of hippocampal volume loss have been shown to distinguish subjects with dementia of the Alzheimer type (DAT) from nondemented controls. In this study, we obtained magnetic resonance scans in 18 subjects with very mild DAT (CDR 0.5) and 26 age-matched nondemented controls (CDR 0) 2 years apart.

Untreated depression and hippocampal volume loss.

Objective: The purpose of this study was to investigate the effect of antidepressant treatment on hippocampal volumes in patients with major depression.

Method: For 38 female outpatients, the total time each had been in a depressive episode was divided into days during which the patient was receiving antidepressant medication and days during which no antidepressant treatment was received. Hippocampal gray matter volumes were determined by high resolution magnetic resonance imaging and unbiased stereological measurement.

High-dimensional mapping of the hippocampus in depression.

Objective: Abnormalities of the hippocampus may play a role in the pathophysiology of depression, but efforts to identify a structural abnormality in this brain structure among depressed patients have produced mixed results. Previous research may have been limited by exclusive reliance on measures of hippocampal volume. High-dimensional brain mapping is a new analytic method that quantitatively characterizes the shape as well as volume of a brain structure.