Biological Explanations

Biological Explanations

Genetics

• Autism Spectrum Disorder (ASD) has a strong genetic basis, as indicated by twin and family studies.
• Research suggests that there are multiple genes involved in ASD, rather than a single ‘autism gene’.
• Genetic variations associated with ASD often disrupt communication between neurons and contribute to neuronal developmental disorders.
• Genetic susceptibility to autism can be inherited, but may also occur through new mutations.

Neurological Abnormalities

• Autistic individuals often have an increased total brain volume, resulting from accelerated growth after birth.
• There may be structural abnormalities in several brain regions, including the prefrontal cortex, amygdala, and cerebellum.
• Unusual patterns of brain connectivity can be observed in ASD, with over-connectivity in some regions and under-connectivity in others.

Neurochemical Factors

• There is evidence of altered neurotransmitter function in ASD, particularly in the serotonin and glutamate/GABA systems.
• Elevated levels of certain neuroactive peptides like oxytocin can influence emotional and social behaviour in people with autism.
• Irregularities in the immune system might lead to neuroinflammation, playing a role in ASD.

Prenatal and Perinatal Factors

• Prenatal exposure to certain drugs (thalidomide, valproic acid) or harmful substances (alcohol, cigarette smoke) can increase the risk of autism.
• Birth complications, including preterm birth, low birth weight, and hypoxia, are associated with an increased risk of ASD.

Limitations of Biological Explanations

• Biological explanations can be reductionist, oversimplifying the causes of ASD by focusing only on biological factors.
• It’s important to consider the interaction of genetic, environmental, and lifestyle factors, not just genetics alone.
• There is also the risk of biological determinism, ignoring the role of individual free will and the potential for positive change in behaviour and symptoms.