What is Autism Spectrum Disorder (ASD)?

One of the most common neurodevelopmental disorders today, autism spectrum disorder (ASD) manifests itself in multiple areas of life, including impairments in speech and social interaction, and repetitive behaviours. While historically Autism carried a radically different meaning, nowadays ASD is an umbrella term, describing “clinically heterogeneous group of neurodevelopmental disorder”such as Asperger syndrome, Childhood Disintegrative Disorder, and more, all of which exhibit certain autistic traits.

Various researchers are trying to shed light on this disorder due to its prevalence. Although there is still a lot to discover, a substantial amount of knowledge has been acquired in terms of its nature.

Diagnosis of Autism Spectrum Disorder

Although ASD is an early-onset disorder and the signs emerge at 12 months of age. The global mean age, however, ranges from 38 to 120 months. The feasibility of the diagnosis no earlier than 18 months of age contributes to this delay. This may prevent early intervention, and thereby improved development of children with ASD.

Tools used in ASD diagnosis focus on the child’s relationship with parents and others. In addition to this, the leading diagnostic tools today are DSM-5 and M-CHAT (Modified Checklist for Autism in Toddlers). Alternatives include the Screening Tool for Autism in Toddlers and Young Children (STATTM), Autism Diagnostic Observation Schedule (ADOSTM), the Autism Diagnostic Interview-Revised (ADI-R), and more.

An individualised differential diagnosis is necessary when dealing with autism spectrum disorders, such as obsessive-compulsive disorder or Gilles de la Tourette. At the same time, comorbidities are prevalent with disorders such as Attention-Deficit Hyperactivity disorder, obsessive-compulsive disorder, developmental language disorder, developmental coordination disorder (dyspraxia), intellectual disability, selective mutism, gastrointestinal disease, and more.

Symptoms of ASD

Impairment in social interaction is a key symptom of ASD, which might show itself in various contexts. Some individuals struggle with non-verbal communication behaviours, including eye contact, misunderstanding, or misusing body language and gestures. Consequently, impairment of social interaction, difficulty maintaining relationships, and other difficulties are some of the hallmarks of ASD.

Another key area of impairment is speech as part of Restricted Repetitive Interests and Behaviors (RRBs). In some ways, this might be similar to other disorders such as Tourette’s. However, in the case of ASD, individuals do not exhibit coprolalia (speech laced with obscenities). Instead, they demonstrate vocal “tics” such as humming and verbal tics in the form of immediate or delayed echolalia (repeating others’ speech).

Aside from speech, repetitive or restricted behaviours also manifest in movement play, resistance to change, fixation on certain interests, intensity in responding to sensory inputs, and more. Compulsive behaviours are common among individuals with autism spectrum disorders that may change over time, making it difficult to observe and diagnose ASD.

Warning Signs

A timely diagnosis of autism spectrum disorder is crucial. However, limitation of diagnostic tools and the nature of the condition make it difficult to diagnose ASD before the suggested age of three.

Therefore, it is vital to look out for signs as a caregiver. Early signs of autism may include lack of responsiveness to one’s name and discomfort with keeping eye contact, speech delay, extreme behavioral reactivity, disruption in social-communicative, play, and motor development. Parents tend to grow concerned in the 2^nd year of life, even if the signs are present beforehand.

Causes of Autism Spectrum Disorder

The current knowledge in terms of what causes autism spectrum disorder (ASD) is limited. Nevertheless, there is empirical evidence to show certain biological and environmental factors behind it. For instance, differences have been identified in cerebellar architecture and connectivity. Furthermore there are abnormalities in the limbic system, and cortical alterations in the temporal lobe. Additionally, Genetics plays an important role since siblings of ASD patients are at higher risk for the condition.

Other factors associated with an increased risk could include parental age, nutrition, infection during pregnancy, prenatal stress, drugs, and more. Although, genetics appear to have a significant role in the etiology, phenotypic expression varies across cases. The risks are, therefore, “modulated by prenatal, perinatal, and postnatal environmental factors”.

Treatment Options

Treatment of autism spectrum disorder (ASD) primarily aims to improve quality of life and provide people with the skills and abilities they need. There are currently two pathways to achieve this – behavioural and pharmacological therapies.

Among behavioural treatment options, Early Intensive Behavioral Intervention (EIBI) is the most prominent and well-studied. This intervention utilises the principles of Applied Behavioral Analysis (ABA) and modifies behaviour via conditioning. Conversely, Naturalistic, Developmental, Behavioral Intervention (NDBI) takes place in a natural environment. This intervention attempts to normalise daily distractions, while facilitating social interaction.

As for the alternative to behavioral treatment, pharmacological therapies usually involve Abilify (aripiprazole) and Risperdal (risperidone). These medicines have been FDA-approved for ASD but were not specifically developed against it. The majority of ASD treatment focuses on symptoms and aims to alleviate in particular symptoms resulting from comorbidities. For instance, Melatonin helps with sleep disturbances; valproic acid is useful against mood swings, bipolar disorders, and seizures. It is important to assert, that the efficacy of most treatments currently available for ASD is limited. There is more to investigate to improve current treatment options.