Regional structural hypo- and hyperconnectivity of frontal-striatal and frontal-thalamic pathways in behavioral variant frontotemporal dementia.

Behavioral variant frontotemporal dementia (bvFTD) has been predominantly considered as a frontotemporal cortical disease, with limited direct investigation of frontal-subcortical connections. We aim to characterize the grey and white matter components of frontal-thalamic and frontal-striatal circuits in bvFTD. Twenty-four patients with bvFTD and 24 healthy controls underwent morphological and diffusion imaging. Subcortical structures were manually segmented according to published protocols. Probabilistic pathways were reconstructed separately from the dorsolateral, orbitofrontal and medial prefrontal cortex to the striatum and thalamus. Patients with bvFTD had smaller cortical and subcortical volumes, lower fractional anisotropy, and higher mean diffusivity metrics, which is consistent with disruptions in frontal-striatal-thalamic pathways. Unexpectedly, regional volumes of the striatum and thalamus connected to the medial prefrontal cortex were significantly larger in bvFTD (by 135% in the striatum, p = .032, and 217% in the thalamus, p = .004), despite smaller dorsolateral prefrontal cortex connected regional volumes (by 67% in the striatum, p = .002, and 65% in the thalamus, p = .020), and inconsistent changes in orbitofrontal cortex connected regions. These unanticipated findings may represent compensatory or maladaptive remodeling in bvFTD networks. Comparisons are made to other neuropsychiatric disorders suggesting a common mechanism of changes in frontal-subcortical networks; however, longitudinal studies are necessary to test this hypothesis.

Prevalence and symptomatology of catatonia in elderly patients referred to a consultation-liaison psychiatry service.

OBJECTIVES: To determine the prevalence and clinical correlations of catatonia in patients aged over 65 years who are referred to a consultation-liaison service within a regional area of Australia. Additionally, to examine if the use of standardised screening tools is likely to change the rate of diagnosis of catatonia within the consultation-liaison service. METHODS: One hundred and eight referrals from general hospital wards were assessed using the Bush-Francis Catatonia Screening Instrument (BFCSI) and associated examination; each consented patient was screened for catatonic symptoms. If two or more signs were present on the BFCSI, then severity was rated using the Bush-Francis Catatonia Rating Scale. These clinical characteristics were compared with their socio-demographic and medical data. RESULTS: Prevalence of catatonia was 5.5%. The most common symptoms appeared to be rigidity, posturing and immobility (67% of cases), and were elicited through routine psychiatric examination. CONCLUSIONS: Routine psychiatric history and examination are likely sufficient to elicit catatonic signs in a consultation-liaison setting. Standardised screening examination may be more suited for conducting research or for use when examining for catatonia in psychiatric inpatient settings.

The Australian, US, Scandinavian Imaging Exchange (AUSSIE): an innovative, virtually-integrated health research network embedded in health care.

OBJECTIVE: To describe the development, design and function of an innovative international clinical research network for neuroimaging research, based in Australia, within a joint state health service/medical school. This Australian, US, Scandinavian Imaging Exchange (AUSSIE) network focuses upon identifying neuroimaging biomarkers for neuropsychiatric and neurodegenerative disease. METHODS: We describe a case study of the iterative development of the network, identifying characteristic features and methods which may serve as potential models for virtual clinical research networks. This network was established to analyse clinically-derived neuroimaging data relevant to neuropsychiatric and neurodegenerative disease, specifically in relation to subcortical brain structures. RESULTS: The AUSSIE network has harnessed synergies from the individual expertise of the component groups, primarily clinical neuroscience researchers, to analyse a variety of clinical data. CONCLUSION: AUSSIE is an active virtual clinical research network, analogous to a connectome, which is embedded in health care and has produced significant research, advancing our understanding of neuropsychiatric and neurodegenerative disease through the lens of neuroimaging.