Autism Spectrum Disorder: Understanding its Symptoms, Causes, and Treatments
Autism spectrum disorder (ASD), commonly referred to as autism, is a neurological and developmental disorder that impacts social interaction, communication, learning, and behavior. It is a spectrum of conditions related to brain development.
ASD can cause individuals to be hypersensitive to sensory information. The brain's thalamus, which manages sensory information, may relay excessive information in individuals with ASD, leading to sensory overload.
Globally, approximately 1 percent of children are diagnosed with autism. In the United States, the prevalence is higher, with one in 36 children and one in 45 adults diagnosed with the condition. The disorder affects around 4 percent of boys and 1 percent of girls. The prevalence has almost tripled since 2000 when it was one in 150.
ASD does not have a single definitive cause; rather, it is believed to be a result of a combination of genetics, environmental factors, and brain-structure issues.
Recognizing the Symptoms and Early Signs of Autism
The term "on the spectrum" is used to describe individuals who share core characteristics of autism, while acknowledging that each person's autistic experience is unique, complex, and can change over time.
It is misleading to think of autism on a linear spectrum, as it suggests that a person can have "more" or "less" autism, leading to oversimplified labels such as "higher" or "lower functioning." Instead, autism is better understood as a range of diverse traits, strengths, and challenges that vary for each individual.
Early Signs
The initial signs of autism generally appear in early childhood and can be detected through screening in children as young as 12 months old or as old as 24 months. However, the condition may be overlooked until much later.
Early signs of ASD by age include limited smiling, eye contact, or reciprocal social interactions; diminished babbling or gestures; reduced response to name; repetitive behaviors; unusual play; lack of single words, compensatory gestures, and pretend play; limited joint attention; and little to no spontaneous two-word phrases.
Signs and Symptoms
Common behaviors observed in individuals with ASD include minimal or inconsistent eye contact with others, appearing disinterested or inattentive when others are speaking, rarely sharing enthusiasm or feelings about objects or activities, avoiding physical affection and preferring solitary play, not responding or taking a long time to respond when called by name, limited or delayed speech or loss of previously acquired words, struggling with the give-and-take aspect of conversations, echoing words or phrases without grasping their meaning, having trouble comprehending basic questions or instructions, relying on memorized scripted speech instead of using spontaneous language, using pronouns incorrectly, talking extensively about specific topics without recognizing others’ disinterest or allowing them to contribute, using facial expressions and gestures that are inconsistent with their verbal messages, exhibiting an unusual voice quality, struggling to grasp others’ perspectives or anticipate their behavior, showing little emotional expression and appearing unaware of others’ emotions or exhibiting abnormal expressions of empathy, struggling to understand nonverbal cues such as body language or tone of voice, not developing close personal relationships, especially outside the family, lack of speech, in severe cases, taking things very literally, such as not understanding sarcasm or expressions such as “it’s raining cats and dogs.”
Autism Signs in Females
Autism symptoms in women and girls may differ from those in males. Autistic females may exhibit enhanced reciprocal conversation skills, improved understanding of verbal and nonverbal communication, greater ability to adapt their behavior to different situations, less noticeable repetitive behaviors, and more socially accepted special interests. Research indicates that females are more likely to mask their autism symptoms to fit in than males.
What Causes Autism?
Research suggests that autism arises from a combination of genetic and environmental factors, as well as abnormal brain development.
Genetics
Genetic factors are believed to contribute 40 percent to 80 percent of autism risk. Over 1,000 genes have been linked to ASD, although many associations remain unconfirmed. Common gene variations may increase ASD risk, but most have a small individual effect, and not everyone with these variations develops ASD.
Brain Development
Research suggests that during brain development, individuals with ASD may have an excess of neurons and overgrowth in parts of the brain’s outer layer, the cortex. Additionally, there are irregular areas where the typical structure of the cortex is disrupted. The cortex normally has six layers, formed before birth, each with specialized neurons and connections. These abnormalities are seen in the frontal and temporal lobes, regions involved in emotions, social behavior, and language. These differences are believed to contribute to the social, communication, and cognitive challenges associated with autism.
Environmental Factors
Environmental factors can range from infections and diseases to toxins and maternal health during pregnancy. They include certain diseases, prenatal infections, maternal immune conditions, prenatal exposure to air pollution, exposure to toxins in the womb, lower levels of manganese and zinc, maternal diabetes and obesity, birth complications, assisted reproductive technology, and paternal cannabis use.
Childhood Vaccines
Although authoritative organizations such as the World Health Organization (WHO), the American Academy of Pediatrics (AAP), and the U.S. Centers for Disease Control and Prevention (CDC) assure parents that there is no link between childhood vaccines and autism, some scientists call for further study.
Bottom Line
Autism is a complex disorder with a myriad of symptoms and causes. It is crucial to understand that each individual's experience with autism is unique and can change over time. While there is no definitive cause, research suggests a combination of genetic, environmental, and brain-structure factors. What are your thoughts on this complex disorder? Share this article with your friends and let them know what you think. Don't forget to sign up for the Daily Briefing, which is available every day at 6 pm.
Autism Spectrum Disorder: Understanding its Symptoms, Causes, and Treatments
Autism spectrum disorder (ASD), commonly referred to as autism, is a neurological and developmental disorder that impacts social interaction, communication, learning, and behavior. It is a spectrum of conditions related to brain development.
ASD can cause individuals to be hypersensitive to sensory information. The brain's thalamus, which manages sensory information, may relay excessive information in individuals with ASD, leading to sensory overload.
Globally, approximately 1 percent of children are diagnosed with autism. In the United States, the prevalence is higher, with one in 36 children and one in 45 adults diagnosed with the condition. The disorder affects around 4 percent of boys and 1 percent of girls. The prevalence has almost tripled since 2000 when it was one in 150.
ASD does not have a single definitive cause; rather, it is believed to be a result of a combination of genetics, environmental factors, and brain-structure issues.
