As an infant Amelia Cook was late to babble, walk, and talk. She responded to her name only when she was around 3 years of age. Although her parents felt something was amiss about her development, they did not suspect her to be on the spectrum. “She was quite friendly with most people and a happy, joyous baby,” says Peter Cook, her dad and a resident of Arenac County, Michigan. She was diagnosed at 6 years and is now in therapy. Her maternal cousin, William, on the other hand, was diagnosed when he was 2 years. His diagnosis was immediate because of the manifestation of symptoms.
Very recent research suggests genetic and hormonal differences protect girls from certain co-morbid conditions that are highly associated with ASD. Therefore, ASD is statistically less likely to be a correct diagnosis in females and males presenting with similar symptoms. Research also suggests that ASD presents itself differently in men and women, as a result, many women are being misdiagnosed, diagnosed at a later age, or going undiagnosed. The girls end up missing out on crucial development support that they need. Behavioral data and preliminary neuroimaging studies suggest ASD manifests differently in girls and boys. Science is now finding out that girls on the spectrum are different from typically developing girls in how and where their brains processes social information. But they are not similar to boys with ASD. Each girl's brain instead looks like that of a neurotypical boy of the same age, with lower levels of activity in regions associated with socializing. It is important to note that females with autism may be closer to neurotypical males in their social abilities than either neurotypical girls or boys on the spectrum.
Quite a few women, like Amelia, are diagnosed at a later age because ASD can have varied symptoms in females. Symptoms such as delayed speech, lack of socialization, social awkwardness, unusual fixations, difficulty “paying attention”, are misdiagnosed as conditions such as “speech delayed”, attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), and mood disorders such as depression. This could be because medical personnel have a limited understanding of the range of ASD symptoms. It could be because girls are more likely to have “milder” symptoms due to the aforementioned biological differences. Although not as strictly today, boys and girls tend to be raised with different social expectations, and are exposed to different types of play, in Western society. For example, most girls do not develop narrowed fixations and interests, however, when they do the subject of the fixation tends to be very different than the subjects of male fixations. In other words, boys with ASD tend to fixate on stereotypically “boy” interests such as train timetables and numbers. The diagnostician may not realize that a little girl insisting that her dolls be dressed in specific clothes, in a specific order, is a type of fixation or narrow interest that fits the mould of a “classic” ASD symptom of rigidity. These differences in neuro-biology, intensity of symptoms, as well as range of symptoms, together may account for the apparent disparity of prevalence of ASD in males and females.
As awareness and understanding of autism grows with time and research, more women are likely to be diagnosed, and future generations of women will benefit from the advances made in science and research. However, more research still needs to be done to formulate better and gender-neutral diagnostic tools to ensure that all children impacted by ASD get the early and medically necessary interventions that they need to thrive.