The Causes, Signs, and Symptoms of Autism

Autism spectrum disorder (ASD) and autism are both interchangeably identified as a group of complex disorders related to brain development. The disorders belonging to this group are generally characterized, in varying contexts, by problems in nonverbal and verbal communication, repetitive behaviors, and social interaction.

The publication of the DSM-5 diagnostic manual released in May 2013 merged all autism disorders into one umbrella diagnosis termed ASD. Before this, they were known by distinct subtypes, such as the following:

Asperger Syndrome
Autistic Disorder
Childhood Disintegrative Disorder
Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS)
What Causes Autism?

Over the course of the last 5 years, researchers have identified a variety of rare gene mutations or mutations to be associated with ASD. A small portion of these are enough to lead to autism on their own. However, most cases of ASD or autism seem to occur due to a range of environmental factors and autism risk genes that influence brain development in earlier stages.

While a genetic predisposition of autism is present, several environmental or non-genetic factors seemingly increase the risk of a child to be autistic. The most apparent evidence of such autism risk factors includes occurrences during and before birth.

The evidence consists of specific difficulties at the time of birth (particularly the ones relating to oxygen deprivation to the child’s brain), maternal illness during pregnancy, and advanced age of parent at the time of conception (for both the mother and father). It is imperative to remember that such factors, on their own, aren’t capable of causing autism. Instead, combined with genetic autism risk factors, they seem to increase the risks modestly.

Early Signs and Symptoms of Autism in Toddlers

In case autism is identified during infancy, the resulting treatment is likely to take complete advantage of the toddler’s brain and its remarkable plasticity. Despite the fact that autism can be difficult to diagnose before the baby reaches 24 months of age, some signs and symptoms mostly surface between the ages of 12 and 18 months. Once signs are identified by 18 months of the child’s age, intensive treatment can possibly help and rewire the brain, resultantly reversing the symptoms.

Children and toddlers that are likely to have autism appear to have the following signs and symptoms. They don’t:

Follow gestures when things are pointed out
Imitate facial expressions and movements
Make basic requests, such as asking for help
Make eye contact
Make noises for getting attention
Play with people
Reach out when being picked up
Respond to cuddling or initiate it on their own
Respond to their name, or to the sound of a familiar voice
Share interest or enjoyment
Smile back when smiled at
Visually follow objects
Wave goodbye, point, or use other communicative gestures