Autism spectrum disorder (ASD) is a broad term used to describe a group of neurodevelopmental disorders. These disorders are characterized by communication and social interaction problems. Individuals with ASD often exhibit restricted, repetitive, and stereotyped symptoms or behavior patterns.
ASD is found in people all over the world, regardless of race, culture, or economic background. Autism occurs more often in boys than girls, with a ratio of 4 males to 1 female. There is evidence that the cases of ASD are increasing. Some attribute this increase to environmental factors. However, experts debate whether there is a real increase in cases or whether there are just more frequent diagnoses.
What are the different types of autism?
The DSM (Diagnostic and Statistical Manual of Mental Disorders) is published by the American Psychiatric Association (APA) and is used by clinicians to diagnose a variety of psychiatric disorders. The fifth and most recent edition of the DSM was published in 2013. DSM-5 currently identifies five ASD subtypes or specific patterns, which are:
With or without mental disorders
With or without language impairment
Associated with a known medical or genetic condition or an environmental factor
Along with other neurological, psychological or behavioral disorders
with catatonia
A person can have one or more of these diagnoses.
Prior to DSM-5, individuals on the autism spectrum were diagnosed with one of the following disorders:
Autism disorder
Asperger’s syndrome
Pervasive Developmental Disorder Not Classified (PDD-NOS)
Childhood dissociative disorder
It is important to note that a person who has received one of these previous diagnoses has not lost their diagnosis and does not need to be re-evaluated. According to the DSM-5, the broader diagnosis of ASD includes disorders such as Asperger’s syndrome.
What are the symptoms of autism?
Symptoms of autism are usually evident in early childhood, between 12 and 24 months of age. However, symptoms may appear sooner or later. Early symptoms may include significant delays in language or social development. DSM-5 divides the symptoms of autism into two categories: communication and social interaction problems, and restricted or repetitive patterns of behavior or activities.
Communication and social interaction problems include the following:
Communication issues, including difficulty sharing feelings, sharing interests, or maintaining previous and subsequent conversations
Nonverbal communication problems, such as difficulty maintaining eye contact or reading body language
Difficulty developing and maintaining relationships
Restricted or repetitive patterns of behavior or activities include:
Repetitive movements, movements or speech patterns
Rigid adherence to certain routines or behaviors
Increased or decreased sensitivity to specific sensory information from your environment, such as a negative reaction to a specific sound
Persistent symptoms or concerns
Individuals in each group are evaluated and the severity of their symptoms is noted. To receive a diagnosis of ASD, a person must show all three symptoms in the first group and at least two symptoms in the second group.
What factors cause autism?
The exact cause of ASD is unknown. The latest research shows that there is no single cause.
Some suspected risk factors for autism include:
Having a first-degree family member with autism
Genetic mutations
Fragile X syndrome and other genetic disorders
Having older parents
Low birth weight
Metabolic imbalance
Exposure to heavy metals and environmental toxins
History of viral infections
Fetal exposure to valproic acid (Depakene) or thalidomide (Thalidomide) drugs
According to studies by the National Institute of Neurological Disorders and Stroke (NINDS), both genetic and environmental factors may play a role in whether a person develops autism. However, many sources, old and new, have concluded that this disorder is not caused by the vaccine. A controversial 1998 study suggested a link between autism and the measles, mumps, and rubella (MMR) vaccine. However, this research was criticized by other researches and finally refuted in 2010.
