Alteration of thalamocortical circuitry in schizophrenia

Acta Neuropathologica, 2009

The thalamus provides a nodal link for multiple functional circuits that are impaired in schizophrenia (SZ). Despite inconsistencies in the literature, a meta analysis suggests that the volume of the thalamus relative to that of the brain is decreased in SZ. Morphometric neuroimaging studies employing deformation, voxel-based and region of interest methodologies suggest that the volume deWcit preferentially aVects the thalamic regions containing the anterior and mediodorsal nuclei, and the pulvinar. Postmortem design-based stereological studies have produced mixed results regarding volume and neuronal deWcits in these nuclei. This review examines those aspects of thalamic circuitry and function that suggest salience to SZ. Evidence for anomalies of thalamic structure and function obtained from postmortem and neuroimaging studies is then examined and directions for further research proposed.

Biological psychiatry, 1999

Background: Thalamic abnormalities resulting in impaired attention and information processing may form a foundation for cognitive and perceptual disturbances in schizophrenia. Measurements of the thalamus in patients with schizophrenia have shown reductions relative to normal comparison subjects. Methods: In the current project, magnetic resonance images of the brain were obtained in 10 male and 11 female subjects with paranoid-type schizophrenia, and 15 male and 12 female normal comparison subjects. Total brain and bilateral thalamic volumes were calculated. Results: There were no significant diagnosis, hemisphere, or gender differences in thalamic volumes. Conclusions: Structural thalamic abnormalities are not likely to universally and parsimoniously explain the schizophrenia phenotype. Abnormal thalamic size in patients with schizophrenia should be understood as reflecting one of several possible structural abnormalities contributing to production of the schizophrenia phenotype, but must be regarded with caution unless paired with functional studies.

Biological Psychiatry, 2000

The thalamus is a brain region of interest in the study of schizophrenia because it provides critical input to brain regions such as the prefrontal, cingulate, and temporal cortices, where abnormalities have been repeatedly observed in patients with schizophrenia. Postmortem anatomic studies have rarely investigated the thalamus in this population. Methods: Postmortem tissue was obtained from the left hemisphere of eight male schizophrenic patients and eight male age-matched control subjects. The optical dissector stereologic procedure was used to count neurons in the mediodorsal (MD) and anteroventral/anteromedial (AV/ AM) nuclei of the thalamus. Results: The number of neurons and volume of the MD were significantly reduced by 35% and 24%, respectively. The MD cell number reduction was a consistent finding; every control subject had more and every schizophrenic subject had fewer than 3.5 million neurons. Neuron number was also significantly reduced (16%) in the AV/AM nuclei.

American Journal of Psychiatry, 2004

Postmortem and neuroimaging studies of schizophrenia have reported deficits in the volume of the thalamus and its component nuclei. However, the pattern of shape change associated with such volume loss has not been investigated. In this study, alterations in thalamic volume, shape, and symmetry were compared in subjects with and without schizophrenia. Method: T 1-weighted magnetic resonance scans were collected in 52 schizophrenia and 65 comparison subjects matched for age, gender, race, and parental socioeconomic status. High-dimensional (large-deformation) brain mapping was used to assess thalamic morphology.

American Journal of …, 1999

The Journal of Comparative Neurology, 2004

The mediodorsal thalamic nucleus (MD) is the principal relay nucleus for the prefrontal cortex, a brain region thought to be dysfunctional in schizophrenia. Several, but not all, postmortem studies of the MD in schizophrenia have reported decreased volume and total neuronal number. However, it is not clear whether the findings are specific for schizophrenia nor is it known which subtypes of thalamic neurons are affected. We studied the left MD in 11 subjects with schizophrenia, 9 control subjects, and 12 subjects with mood disorders. Based on morphological criteria, we divided the neurons into two subclasses, presumably corresponding to projection neurons and local circuit neurons. We estimated MD volume and the neuron number of each subclass using methods based on modern unbiased stereological principles. We also estimated the somal volumes of each subclass using a robust, but biased, approach. In addition, we investigated the left MD in four cynomolgus monkeys chronically exposed to haloperidol and in four control monkeys in order to assess the possible effects of antipsychotic medications. The three human subject groups did not differ in any of the measures. In addition, no differences were observed between the two groups of monkeys. Thus, these findings do not support the hypothesis that the MD is a locus of pathology in schizophrenia, although they cannot rule out important functional or structural changes in parameters not measured. Like other studies, this investigation is subject to the limitations involved in sampling from a heterogeneous population emphasizing the need to continue to improve the application of robust, unbiased techniques to quantitative studies of this complex brain disorder.

Schizophrenia Research, 2004

The size of the thalamus was assessed in 106 patients with schizophrenia and 42 normal controls using high-resolution magnetic resonance imaging. The thalamus was traced at five axial levels proportionately spaced from dorsal to ventral directions. Patients with schizophrenia had significantly smaller thalamic areas at more ventral levels. Thalamic size was positively associated with frontal lobe and temporal lobe size. The effects were most marked in the patients with poorer clinical outcome (i.e., ''Kraepelinian'' patients). These findings are consistent with post-mortem and MRI measurement suggesting reduction in volume of the pulvinar, which occupies a large proportion of the ventral thalamus and which has prominent connections to the temporal lobe. D

Biological Psychiatry, 2001

Background: This article presents a meta-analysis of thalamic size reduction in schizophrenia. Methods: Reviewed studies were based on magnetic resonance imaging or postmortem material and included measures of thalamic volume or thalamic area in schizophrenic patients and comparison subjects. Meta-analysis I was based on absolute thalamic values (not controlled for overall brain size), and Meta-analysis II evaluated thalamic size adjusted for brain size. Results: Meta-analysis I included data from 15 studies (485 schizophrenic subjects and 500 control subjects). Twelve (80%) of the studies had negative effect sizes, which is consistent with the hypothesis that thalamic size is smaller in schizophrenic subjects compared to control subjects. The composite effect size was Ϫ0.29 (p Ͻ .0001; without outliers: Ϫ0.41, p Ͻ .0001). Meta-analysis II included data from 11 studies (313 schizophrenic patients and 434 control subjects). Ten (91%) of the studies had negative effect sizes. The composite effect size was Ϫ0.35 (p Ͻ .0001; without outlier: Ϫ0.30, p Ͻ .0001). Conclusions: Both meta-analyses indicate a statistically significant, small-to-moderate effect size for thalamic size reduction in schizophrenia; however, the effect size for thalamic size reduction is modest in comparison to that of other structural abnormalities noted in schizophrenia.

Castellologica Bohemica , 2018

Die in das Kuyavian-Vistula-Land ankommenden Deutschen Ritter bauten in den danach kommenden Jahrzehnten eine Reihe von Festungen aus Holz und Erde. Die Festungen sollten das eroberte Land schützen und die Positionen der neuen Ordnung stabilisieren. Das galt insbesondere in der Zeit der bedeutenden sozioökonomischen Veränderungen, die aus der Einführung eines neuen Regelsystems und aus der Entstehung und Entwicklung von neuen Siedlungen erfolgten. Die errichteten Festungen bildeten keine direkte Fortsetzung von früheren mittelalterlichen Siedlungen und sollten als Kolonialisierung und als temporäre Burgen betrachtet werden (diese werden von verschiedenen Formen repräsentiert: Bollwerk, Wallumfang, seltener auch Motte-Typ). Sie wurden entweder an der Stelle der frühmittelalterlichen Siedlungen, oder außerhalb erbaut. Sie wurden mit Bollwerken befestigt und geschützt, die Häuser aus einer leichten Skelettkonstruktion wurden damit kombiniert und dienten den neuen Mönchsherrschern des Landes. Normalerweise enthielten die Festungen auch eine Kapelle und wahrscheinlich ein Refektorium, das aufgrund der Ordensregeln gefordert wurde. Seit der Hälfte des 13. Jahrhunderts (Toruń, Starogród, Balga, Dzierzgoń?) und vor allem seit den 70er Jahren des 13. Jahrhunderts (Bierzgłowo, Grudziądz, Pokrzywno) wurden die ausgewählten Objekte in den Zentren von neu positionierten Kommandanten, die ursprünglich einen Holz-Erde-Charakter hatten, von einfachen Forts zu Ziegelbauten mit charakteristischen Einzelhäusern umgebaut, die sich auf die Lage einer Kapelle beziehen. Die Errichtung von neuen komplexen Flügeln war bis dahin nicht geplant und wurde erst nach Ende des Jahrhunderts laut völlig neuen architektonischen Vorstellungen hinzugefügt. Diese ersten Entwürfe waren wahrscheinlich nie fertiggestellt worden. Der Bau von Umfassungsmauern, die die alten aus Holz und Erde ersetzten, begann mit unregelmäßigen Arrangements mit einzelnen Häusern und Holzhausbauten aus der vorigen Periode (sie ähneln in Form den teutonischen Kommandanten aus dem heutigen Gebiet Deutschlands und Tschechiens, als besonderes Beispiel dafür kann das tschechische Schloss Bradlo mit der ähnlichen räumlichen Konzeption genannt werden). Die Wände wurden in schmalen Fundamentgräben errichtet, Stein - im unteren Teil, Ziegel – höher – und in der Regel ältere Befestigungslinien. Die Erdwerke wurden entweder ganz, oder teilweise entfernt – in den oberen Ebenen. Damals wurden keine anderen Erdwerke durchgeführt, die für die späteren Zeiten charakteristisch waren, also bei einigen Burgen blieb an den Vorhöfen ein differenziertes Terrainprofil.

Paire de Plats aux armes de Camille PERRICHON. Lyon., 2017

Paire de plats de Lyon , de petites dimensions (34 x 24 cm), aux armes de Camille PERRICHON, marqués au dos ; 'Lyon Combe f(écit)'. Ces plats de style moustierain par la forme et le décor, laissent entrevoir l'apprentissage de Joseph COMBE à l'école des VIRY. C’est en 1732 que Joseph COMBE peintre provençal, âgé de 26 ans, vient créer une fabrique dans la Grande Rue de La Guillotière. Joseph COMBE a appris son métier à Moustiers, dans l’atelier de Pierre CLERISSY, comme apprenti de Jean-Baptiste VIRY et l’a exercé pendant 8 ans à Marseille avant de venir à Lyon. En 1733, une manufacture royale de faïencerie s'implante dans le quartier de la Guillotière. Joseph COMBE associé Jacques Marie RAVIER louent au sieur BICHON, une maison qui a pour enseigne « au soleil levant » localisée au 18 grande rue de la Guillotière. Pour contourner une contrainte douanière importante (la Guillotière étant un faubourg). COMBE et RAVIER vont adresser une requête au Conseil du roi par laquelle ils sollicitent pour leur établissement le titre de manufacture royale pour obtenir toute une série d'exemption. Probablement avec l’appui de Messire Camille PERRICHON , Chevalier des ordres Roy secrétaire de la ville de Lyon. Leur requête est exaucée, ainsi COMBE et RAVIER obtiennent un privilège de 10 ans, l'interdiction pour toute personne d'implanter une manufacture concurrente dans Lyon et ses faubourgs, hélas les exemptions des droits de douane leur sont refusées.