The Symptomatology of Autism Spectrum Disorder: An Overview of Clinical Features

By Dr. Adrian Agapito, Medical Chief at DHR Health Behavioral Hospital

What is Autism Spectrum Disorder?

Autism Spectrum Disorder (ASD) is a biologically based mental disorder with a broad range of clinical presentations that can lead to difficulties in social communication and social interactions, in addition to unique repetitive behaviors and restricted interests. Because Autism Spectrum Disorder is also considered to be neurodevelopmental in nature, it usually presents in the first two years of life, with approximately two-thirds of patients presenting with poor communication skills prior to two years old. Because of the significant impact of ASD on a patient’s quality of life, it is very crucial for parents and medical providers alike to be knowledgeable about the symptomatology of ASD.  Early recognition, identification, and confirmation of Autism Spectrum Disorder can ultimately lead to timely management of any behavioral difficulties that may interfere with a patient’s social, academic, and occupational functioning.

Social Difficulties

ASD is first suspected and diagnosed when a child appears to have ongoing difficulties in social communication and social interaction. This can include deficits in social-emotional reciprocity, deficits in nonverbal communicative behaviors critical for social interaction, and deficits in developing, maintaining, and understanding relationships. Patients will often struggle with back and forth communication and are unable to initiate or adequately respond to social interactions. These individuals will also appear to have reduced interests and emotions. Upon observation, patients with ASD will display poor eye contact, as well as lack of facial expressions and nonverbal communication. Patients with ASD will have trouble adjusting to social situations such as group play and overall have no interest in interacting with peers, leading to inability to make friends.

Repetitive Patterns

In addition, ASD is also diagnosed when a child appears to display restricted and repetitive patterns of behavior, interests or activities. Repetitive behaviors can include motor movements, use of objects, or repetitive speech. For example, a patient with ASD may be observed to be lining up toys in a certain way, repeating what other people say without logical explanation, or displaying repetitive physical movements. These individuals are extremely adherent to specific routines and are unable to adapt to changes in their ritualistic behaviors. Patients with ASD become distressed, anxious, and irritable when forced to deviate from their routines, and they have very rigid patterns of thought. These patients are the type of patients that often have to take the same route or eat the same type of food every day. Patients with ASD also have fixated interests that are abnormal in intensity or focus. They can be extremely attached, focused on, or preoccupied with specific objects that may appear to have no relevance to any other person.

With growing awareness of the symptomatology and diagnostic criteria for Autism Spectrum Disorder, we can hopefully achieve the ultimate goal of early management of ASD to include behavioral and educational interventions such as implementing a highly supportive academic environments and utilizing psychopharmacologic interventions to treat inattention, impulsivity, aggression, anxiety, depression, obsessive-compulsive traits, and sleep disturbances that are often present in Autism Spectrum Disorder. In the midst of the COVID-19 pandemic which has led to a resurgence of mental health related illnesses across the country, patients with Autism Spectrum Disorder continue to be one of the most vulnerable populations given their inherently poor coping skills and vulnerability to psychiatric decompensation.


American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: Author.

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