Neurological soft signs and neurodevelopment in schizophrenia and their unaffected first-degree relatives

Research Opportunity
Masters by Research, Honours, Master of Biomedical Science
Number of Honour Places Available
1
Department
Psychiatry
Group Leader Email Number Webpage
Dr Vanessa Cropley vcropley@unimelb.edu.au 83441876 Personal web page
Primary Supervisor Email Number Webpage
A/Prof Andrew Zalesky azalesky@unimelb.edu.au

Project Details

Subtle motor and sensory abnormalities, or neurological soft signs (NSS), are frequently reported in schizophrenia. Such deficits have been reported at different stages of the illness, including in individuals at risk for psychosis, first-episode psychosis and chronic schizophrenia, as well as healthy first-degree relatives of individuals with the disorder. This has led to proposals that NSS may be an endophenotype of the disorder. However, increased prevalence of NSS has also been reported in other developmental disorders including autism and learning disorder. As such, NSS may represent a non-specific marker of abnormal neurodevelopment. Despite the relatively well-established findings of NSS in schizophrenia, the brain morphological changes underlying these signs are only partly understood.

A number of studies using structural magnetic resonance imaging (MRI) have examined the relationship between increased NSS and morphological abnormalities in both cortical and subcortical structures in individuals with schizophrenia. These studies point to structural abnormalities in the precentral gyrus, the cerebellum, the inferior frontal gyrus, and the thalamus as correlates of NSS. However these studies have measured brain volume, which are heavily influenced by factors occurring after the onset of the illness. In contrast, intracranial volume (ICV) and gyrification, are understood to be determined by genetic and early developmental factors, and thus may provide more specific markers of neurodevelopment. To date, the relationship between NSS and brain neurodevelopmental markers in schizophrenia and their unaffected relatives has not been assessed.

The aim of this study is to: i) investigate the presence of NSS in established schizophrenia and their unaffected first-degree relatives; ii) determine whether individuals with schizophrenia, as well as their unaffected relatives, exhibit a pattern of abnormal neurodevelopment in comparison to healthy controls, and iii) determine whether this “neurodevelopmental” profile is associated with NSS.

MRI, clinical and cognitive data from individuals with established schizophrenia, their unaffected first-degree relatives and matched healthy controls, will be obtained from an existing database. Associations of NSS with brain and cognitive markers of early development, including ICV, gyrification, and premorbid IQ, will be assessed. Secondary analyses will examine associations of NNS with regional grey matter thickness volume and surface area, clinical symptoms (positive and negative symptoms), and cognitive abilities.

The student will be responsible for the development of the proposal and refinement of study hypotheses, conducting a literature review, processing of brain imaging scans and performing statistical analyses. Publication of results is expected at the end of the project.



Faculty Research Themes

Neuroscience

School Research Themes

Neuroscience & Psychiatry



Research Opportunities

Masters by Research, Honours, Master of Biomedical Science
Students who are interested in joining this project will need to consider their elegibility as well as other requirements before contacting the supervisor of this research

Graduate Research application

Honours application

Key Contact

For further information about this research, please contact a supervisor.

Department

Psychiatry

Research Group / Unit / Centre


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