Processing of affective speech prosody is impaired in Asperger syndrome.

Korpilahti et al. (2007) wired up kids with Asperger syndrome and their dads to EEG caps. They played happy, sad, and angry sentences while the team watched which side of the brain lit up.

The same test was given to typical kids and their parents. All groups were asked to just listen quietly so the machine could catch the brain’s first reaction to emotional tone.

The Asperger group showed a weaker and later response in the right side of the brain—the part that usually grabs emotional pitch. Even their fathers had a similar, though smaller, glitch.

Typical listeners showed a quick right-hemisphere spike. The mismatch was clear even though everyone could say what emotion they heard when asked later.

Lecavalier et al. (2006) already showed, one year earlier, that kids with Asperger’s score lower on simple “what emotion is this voice?” tasks. Pirjo’s EEG data now shows why: the brain is not tagging the tone as emotional in the first place.

de Kuijper et al. (2014) later recorded the same kids talking and found their own speech sounded odd even though the words were correct. Together the two papers form a loop—weak input processing leads to quirky output.

Globerson et al. (2015) moved the test to high-functioning adults with ASD and still found the same prosody problem, proving the issue does not fade with age.

If the brain barely registers emotional pitch, don’t expect clients to pick up sarcasm, warnings, or praise from your tone alone. Add visuals, teach rules, and give clear feedback. Start sessions with quick discrimination drills—happy vs. sad voices—then move to real-life phrases like “nice job” said in flat, happy, or angry tones. Track progress so you know when to shift from explicit lessons to natural settings.