Autism spectrum disorders share three core characteristics, known as the **autistic triad**: 1. **Difficulty with communication** 2. **Difficulty with social relationships** 3. **Inability to understand others' state of mind** (theory of mind deficit) These three are thought to result from inefficiencies in brain structures and pathways that allow neurotypical (NT) individuals to register and process multiple channels of input simultaneously. AS and autism share this triad but differ in **degree of severity** — AS is the most able end of the spectrum, with normal IQ and no language development delay. **Source:** Lovett, *Solutions for Adults with Asperger Syndrome*, Ch 1 (pp22-23) See also: [[AS Neurodevelopmental Not Mental Illness]]