Some types of restricted and repetitive behaviors become more prevalent among autistic children and teenagers over time, depending on their age and intellectual ability, whereas others decrease.

Researchers can roughly project what autistic children’s lives will look like years down the road. But how good is their crystal ball — and what are its benefits?

The high levels of serotonin seen in the blood of some autistic people have confounded scientists for more than half a century. Despite so little progress, some researchers refuse to give up.

People who experience an autism-specific form of anxiety also tend to have an unusually small amygdala, a brain region associated with emotion processing and fear, according to a new unpublished study.

Girls and women with mutations in the autism-linked gene DDX3X may be particularly vulnerable to anxiety and self-harm.

Researchers are just beginning to learn what happens in the brains of autistic children during adolescence to explain their unique social, cognitive and emotional challenges.

Mice missing one copy of the autism-linked gene DDX3X have smaller brains and worse motor skills than mice with both copies of the gene, according to a new unpublished study.

During conversations, girls with autism use “we,” “they” and other plural personal pronouns differently than autistic boys do.

Mutations in POGZ, a gene strongly linked to autism, lead to a signaling imbalance in multiple brain regions in mice, according to two new studies.

This is part 2 of Owen’s story. It tracks his early progress in treatment for autism. Part 1 described his difficult path to a diagnosis.