The insula-claustrum region and delusions in schizophrenia
ABSTRACT We examined the relationship between cerebral gray matter (GM) volume and severity of delusions and hallucinations in adults with schizophrenia.
MRI scans in 43 patients with schizophrenia were acquired. Correlations were computed between GM volume and clinician ratings of hallucinations and delusions.
The analysis revealed significant inverse correlations between ratings of the severity of delusions and volumes of the left claustrum and right insula. Significant correlations were not observed between cerebral GM volume and ratings of hallucinations.
The insula/claustrum region may be critical to the experience of delusions and more careful scrutiny of the claustrum in relation to schizophrenia appears warranted.
SourceAvailable from: PubMed Central[Show abstract] [Hide abstract]
ABSTRACT: The claustrum seems to have been waiting for the science of connectomics. Due to its tiny size, the structure has remained remarkably difficult to study until modern technological and mathematical advancements like graph theory, connectomics, diffusion tensor imaging, HARDI, and excitotoxic lesioning. That does not mean, however, that early methods allowed researchers to assess micro-connectomics. In fact, the claustrum is such an enigma that the only things known for certain about it are its histology, and that it is extraordinarily well connected. In this literature review, we provide background details on the claustrum and the history of its study in the human and in other animal species. By providing an explanation of the neuroimaging and histology methods have been undertaken to study the claustrum thus far-and the conclusions these studies have drawn-we illustrate this example of how the shift from micro-connectomics to macro-connectomics advances the field of neuroscience and improves our capacity to understand the brain.Frontiers in Neuroinformatics 11/2014; 8:83. DOI:10.3389/fninf.2014.00083
[Show abstract] [Hide abstract]
ABSTRACT: The origin, structure, and function of the claustrum, as well as its role in neural computation, have remained a mystery since its discovery in the 17th century. Assessing the in vivo connectivity of the claustrum may bring forth useful insights with relevance to model the overall functionality of the claustrum itself. Using structural and diffusion tensor neuroimaging in N = 100 healthy subjects, we found that the claustrum has the highest connectivity in the brain by regional volume. Network theoretical analyses revealed that (a) the claustrum is a primary contributor to global brain network architecture, and that (b) significant connectivity dependencies exist between the claustrum, frontal lobe, and cingulate regions. These results illustrate that the claustrum is ideally located within the human central nervous system (CNS) connectome to serve as the putative “gate keeper” of neural information for consciousness awareness. Our findings support and underscore prior theoretical contributions about the involvement of the claustrum in higher cognitive function and its relevance in devastating neurological disease. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.Human Brain Mapping 10/2014; 36(3). DOI:10.1002/hbm.22667 · 6.92 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Background: Hallucinations and delusions that complicate Parkinson's disease (PD) could lead to nursing home placement and are linked to increased mortality. Cognitive impairments are typically associated with the presence of hallucinations but there are no data regarding whether such a relationship exists with delusions. Objective: We hypothesized that hallucinations would be associated with executive and visuospatial disturbance. An exploratory examination of cognitive correlates of delusions was also completed to address the question of whether they differ from hallucinations. Methods: 144 PD subjects completed a neuropsychological battery to assess cognition and the SAPS to examine psychosis. Correlational analyses assessed associations between hallucinations and delusions with cognitive domains. Results: 48 subjects (33%) reported psychotic symptoms: 25 (17%) experienced hallucinations without delusions, 23 (16%) had symptoms dominated by delusions. Severity and/or number of hallucination subtypes were significantly correlated with lower scores in language, memory, attention, executive functioning, and visuospatial ability. Correlations with delusions were non-significant. Tests of differences in the size of the correlations between groups revealed a significant relationship between language and visuospatial performance with hallucinations. Conclusions: Cognitive correlates of hallucinations and delusions appear to be different in PD, suggesting distinct pathogenic mechanisms and possibly anatomical substrates. Hence, delusions may not share the same associations with dementia as hallucinations. Since this is a new finding, further studies will be needed to confirm our results.Journal of the Neurological Sciences 10/2014; 347(1-2). DOI:10.1016/j.jns.2014.10.033 · 2.26 Impact Factor