The pattern of cerebral changes associated with NSS clearly supports the model of 'cognitive dysmetria' with a disrupted cortico-cerebellar-thalamic-cortical circuit in schizophrenia. The variety of sites may correspond with the clinical diversity of NSS, which comprises both motor and sensory signs, and with the putative heterogeneity of the pathogenetic changes involved. That the respective associations did not apply for the healthy control group indicates that NSS in patients and controls refer to different pathogenetic factors.
There is increasing histopathological evidence that the olfactory bulb and tract (OBT) is a primary focus of neurodegenerative changes in Alzheimer's disease (AD). Correspondingly, high-resolution magnetic resonance imaging revealed significant atrophy of the OBT in manifest AD. Whether these alterations are already present in mild cognitive impairment, the assumed preclinical stage of AD, has not been investigated yet. OBT volumes were assessed by manual tracing in 29 patients with mild cognitive impairment, 27 patients with probable AD, and 30 healthy controls. In a second step, voxel based morphometry was used to investigate the potential association between OBT atrophy and morphological changes in other brain regions. Patients had significantly lower OBT volumes when compared to controls, with atrophy being most prominent in the AD group. In addition, OBT atrophy was associated with a decreased medial temporal lobe (MTL) gray matter density bilaterally. Our findings indicate that neurodegeneration in OBT and MTL regions is linked and suggest that OBT volume might be a surrogate marker in AD.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.