Effects of hormones, genetics, and sex on typical and atypical brain organization
type: CreativeWork
description: The first part of this thesis discusses developmental influences on the human connectome in relation to autism and attention deficit hyperactivity disorder (ADHD), conditions associated with alterations in brain connectivity and marked by social impairments. It reports an experiment investigating whether the connectomes of individuals with autism or ADHD differ from the connectome of neurotypical individuals, and what the underlying genetic basis could be for any differences in neural architecture. Chapter 2 reports an analysis of networks in children with autism or ADHD, using structural covariance magnetic resonance imaging (scMRI). We found overlapping as well as distinct network features across both conditions. Chapter 3 reports an analysis of how gene expression might be associated with the basic building blocs of these structural covariance networks. We found that synaptic and transcriptionally downregulated genes were replicably associated with cortical thickness differences in children with autism, but not in children with ADHD. In addition, the first part also aims to elucidate the potential modulation effects of sex on autism neurobiology. Chapter 4 reports an analysis of structural covariance networks in male and female adults with and without autism. We found that biological sex is a modulator of neurobiological heterogeneity in autism. Chapter 5 reports pilot data aiming to identify an electrophysiological signature of these network properties using electroencephalography (EEG). We find little evidence for theories about network asymmetry, but indications of altered frontal network integration. The second part of the thesis examines the acute effects of hormones on brain connectomics. Hormones are an integral part of the mechanism of social behaviour. In a series of hormone administration studies, we report experiments to test the acute effects of steroid and peptide hormones on brain functional connectivity (Chapters 6 and 7). Chapter 6 reports an oxyt…
abstract: The first part of this thesis discusses developmental influences on the human connectome in relation to autism and attention deficit hyperactivity disorder (ADHD), conditions associated with alterations in brain connectivity and marked by social impairments. It reports an experiment investigating whether the connectomes of individuals with autism or ADHD differ from the connectome of neurotypical individuals, and what the underlying genetic basis could be for any differences in neural architecture. Chapter 2 reports an analysis of networks in children with autism or ADHD, using structural covariance magnetic resonance imaging (scMRI). We found overlapping as well as distinct network features across both conditions. Chapter 3 reports an analysis of how gene expression might be associated with the basic building blocs of these structural covariance networks. We found that synaptic and transcriptionally downregulated genes were replicably associated with cortical thickness differences in children with autism, but not in children with ADHD. In addition, the first part also aims to elucidate the potential modulation effects of sex on autism neurobiology. Chapter 4 reports an analysis of structural covariance networks in male and female adults with and without autism. We found that biological sex is a modulator of neurobiological heterogeneity in autism. Chapter 5 reports pilot data aiming to identify an electrophysiological signature of these network properties using electroencephalography (EEG). We find little evidence for theories about network asymmetry, but indications of altered frontal network integration. The second part of the thesis examines the acute effects of hormones on brain connectomics. Hormones are an integral part of the mechanism of social behaviour. In a series of hormone administration studies, we report experiments to test the acute effects of steroid and peptide hormones on brain functional connectivity (Chapters 6 and 7). Chapter 6 reports an oxyt…
author: Bethlehem, Richard Alexander Ingmar
language: en
keywords: Autism, Neuroimaging, Genetics, Hormones
license: https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/86816393-b630-46f9-a3c6-ad06cb017d36/download
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2017-10-03
date modified: 2026-07-22T22:24:17Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.13653