Autism Spectrum Disorders: Biology and Neuroscience Course

Lesson 1 • Defining Autism Spectrum Disorders

Core diagnostic features, historical evolution of the ASD concept, and current classification systems are examined. This anchors all subsequent biological content in clinical reality.

Lesson 2 • Co-occurring Conditions and Comorbidities

Intellectual disability, epilepsy, anxiety, and GI disorders frequently co-occur with ASD and complicate biological interpretation. Students learn to account for comorbidities in research analysis.

Lesson 3 • Epidemiology and Prevalence Trends

Global and regional prevalence data, demographic patterns, and methodological factors affecting reported rates are analyzed. Students contextualize biological research within population-level observations.

Lesson 1 • Heritability and Twin Studies

Twin and family studies quantify genetic versus environmental contributions to ASD risk. Students interpret concordance rates and understand the limits of heritability estimates.

Lesson 2 • Common Variants and Polygenic Risk

Genome-wide association studies reveal many common variants of small effect that collectively elevate ASD risk. Students interpret polygenic risk scores and their clinical limitations.

Lesson 3 • Gene-Environment Interactions

Genetic background modulates sensitivity to environmental exposures, producing variable ASD outcomes. Students analyze interaction models and their implications for risk prediction.

Lesson 4 • Rare Variants and De Novo Mutations

Copy number variants, de novo single-nucleotide variants, and chromosomal anomalies account for a significant ASD subpopulation. Students learn to identify high-penetrance genetic risk factors.

Lesson 1 • Neuroinflammation and Immune Dysregulation

Microglial activation, cytokine imbalances, and maternal immune activation are implicated in ASD pathophysiology. Students assess the evidence linking immune dysfunction to neural development.

Lesson 2 • Excitatory-Inhibitory Balance

Disrupted ratios of glutamatergic excitation and GABAergic inhibition are a central ASD hypothesis. Students evaluate evidence from animal models and human studies supporting this framework.

Lesson 3 • mTOR Signaling and Cellular Growth

Hyperactivated mTOR pathway drives abnormal cell growth, synaptic plasticity, and protein synthesis in several ASD subtypes. Students map mTOR dysregulation to observable neural phenotypes.

Lesson 4 • Mitochondrial Function and Oxidative Stress

Elevated rates of mitochondrial dysfunction and oxidative stress markers are documented in ASD populations. Students evaluate how energy metabolism deficits affect neuronal function.

Lesson 1 • Prenatal Brain Development and ASD

Cortical neurogenesis, neuronal migration, and laminar organization are disrupted in ASD during fetal development. Students identify critical windows when genetic and environmental factors exert maximal influence.

Lesson 2 • Early Brain Overgrowth Phenomenon

Accelerated head circumference growth and cortical surface area expansion in the first two years are ASD biomarkers. Students evaluate prospective imaging studies and their predictive value.

Lesson 3 • Postnatal Synaptic Pruning and Maturation

Aberrant synaptic pruning and dendritic spine density changes during early childhood alter circuit refinement in ASD. Students connect pruning deficits to sensory and cognitive symptoms.

Lesson 1 • Functional MRI and Resting-State Networks

Default mode network hypoactivation and atypical task-based activation patterns characterize ASD fMRI profiles. Students link network-level dysfunction to social cognition and executive function deficits.

Lesson 2 • EEG and Electrophysiological Measures

Gamma oscillation abnormalities, reduced mu suppression, and atypical event-related potentials are ASD electrophysiological signatures. Students assess EEG as a cost-effective biomarker tool.

Lesson 3 • Connectivity Models and Network Analysis

Graph-theoretic approaches reveal global underconnectivity and local overconnectivity patterns in ASD brain networks. Students apply network analysis concepts to interpret published connectivity studies.

Lesson 4 • Structural MRI Findings in ASD

Cortical thickness, gray matter volume, and sulcal depth differences are documented across ASD cohorts. Students evaluate methodological variability and replication challenges in structural studies.

Lesson 1 • Oxytocin and Social Neuroscience

Oxytocin modulates social recognition, trust, and affiliative behavior through amygdala and hypothalamic circuits. Students critically assess intranasal oxytocin trial outcomes and mechanistic limitations.

Lesson 2 • Dopamine and Reward Processing

Atypical dopaminergic reward signaling underlies reduced social motivation and repetitive behavior reinforcement in ASD. Students evaluate dopamine pathway findings and their behavioral correlates.

Lesson 3 • GABA, Glutamate, and Pharmacological Targets

GABA-A receptor modulators and mGluR5 antagonists have been tested as ASD treatments based on E/I imbalance theory. Students evaluate preclinical promise versus clinical trial outcomes for these targets.

Lesson 4 • Serotonin System in ASD

Hyperserotonemia in blood and altered central serotonin synthesis are among the most replicated ASD biological findings. Students trace serotonin's role in early brain development and social behavior.

Lesson 1 • Non-Human Primate and Zebrafish Models

Primate models offer greater social complexity, while zebrafish enable high-throughput genetic screening for ASD genes. Students weigh the trade-offs between model complexity and experimental tractability.

Lesson 2 • Environmental and Pharmacological Models

Prenatal valproate exposure and maternal immune activation produce ASD-like behavioral and neural phenotypes in rodents. Students compare environmental model strengths with genetic model limitations.

Lesson 3 • Translational Challenges and Failure Analysis

Most preclinical ASD drug successes have failed in human trials, revealing critical translational gaps. Students analyze reasons for failure and strategies to improve bench-to-bedside translation.

Lesson 4 • Genetic Mouse Models of ASD

Knockout and knockin mice targeting SHANK, neuroligin, and FMR1 genes replicate specific ASD-relevant phenotypes. Students evaluate construct, face, and predictive validity for each model type.

Lesson 1 • Biological Biomarker Discovery

Genomic, proteomic, metabolomic, and neuroimaging biomarkers are being developed to stratify ASD subtypes. Students evaluate biomarker validation criteria and the path from discovery to clinical use.

Lesson 2 • Precision Medicine Approaches

Genotype-informed treatment matching and stratified clinical trials aim to overcome ASD heterogeneity. Students evaluate precision medicine frameworks and their feasibility in current practice.

Lesson 3 • Integrating Biology with Clinical Practice

Biological findings must be translated into actionable guidance for clinicians, educators, and families. Students synthesize course knowledge into a coherent framework for evidence-based professional practice.

Lesson 4 • Early Detection and Prospective Studies

Infant sibling studies and prospective cohorts identify neural and behavioral precursors of ASD before diagnosis. Students assess the sensitivity and specificity of early detection tools.