Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Electronic Thesis and Dissertation Repository

Neurosciences

Autism

Articles 1 - 2 of 2

Full-Text Articles in Medicine and Health Sciences

The Effects Of Pre- And Postnatal Administration Of Propionic Acid And Lipopolysaccharide On The Behaviour Of Adolescent Male And Female Rats, Kelly A. Foley Nov 2013

The Effects Of Pre- And Postnatal Administration Of Propionic Acid And Lipopolysaccharide On The Behaviour Of Adolescent Male And Female Rats, Kelly A. Foley

Electronic Thesis and Dissertation Repository

The gut microbiome plays an important role in immune functioning and neurodevelopment. Altered microbiome composition, leading to short chain fatty acid, and/or immune system dysfunction has been observed in children with autism spectrum disorders (ASD). This thesis describes the developmental influence of prenatal exposure to propionic acid (PPA), a metabolic fermentation product of enteric bacteria, or prenatal exposure to lipopolysaccharide (LPS), a bacterial mimetic and product of enteric bacteria, on a range of behaviours in male and female neonatal, adolescent and adult rats. Study one evaluated the effects of prenatal PPA and LPS, and postnatal PPA, on developmental milestones in …


Magnetic Resonance Imaging Of Brain Tissue Abnormalities: Transverse Relaxation Time In Autism And Tourette Syndrome And Development Of A Novel Whole-Brain Myelin Mapping Technique, Yann Gagnon Mar 2013

Magnetic Resonance Imaging Of Brain Tissue Abnormalities: Transverse Relaxation Time In Autism And Tourette Syndrome And Development Of A Novel Whole-Brain Myelin Mapping Technique, Yann Gagnon

Electronic Thesis and Dissertation Repository

The transverse relaxation time (T2) is a fundamental parameter of magnetic resonance imaging sensitive to tissue microstructure and water content, thus offering a non-invasive approach to evaluate abnormalities of brain tissue in-vivo. Prevailing hypotheses of two childhood psychiatric disorders were tested using quantitative T2 imaging and automated region of interest (ROI) analyses. In autism, the under-connectivity theory, which proposes aberrant connectivity within white matter (WM) was assessed, finding T2 to be eleveted in the frontal and parietal lobes, while dividing whole brain data into neurodevelopmentally relevant WM ROIs found increased T2 in bridging and radiate WM. In Tourette syndrome, tissue …