Hematological and immunological acute mental stress responses of people who are severely and profoundly mentally retarded.

McSweeney et al. (2000) ran a five-minute structured task with 28 adults who have severe or profound intellectual disability. The task asked them to move pegs on a board while staff watched.

Before and after the task the team drew blood. They looked for quick changes in red cells, white cells, and blood proteins.

Right after the short task the adults’ blood got thicker. Granulocytes, red cells, hemoglobin, and plasma protein all went up. Monocytes went down.

The shift is called hemoconcentration. It is the same thing that happens when your body prepares for fight-or-flight.

van Swieten et al. (2025) seems to say the opposite. They showed that letting adults with mild ID listen to music lowered their physiological stress. The difference is the trigger: a demanding task raises arousal, while chosen music lowers it.

Berger et al. (2015) and DeRoma et al. (2004) extend the timeline. They found that weeks or months of real-life stress—like missile alerts, staff changes, or bereavement—lead to more post-traumatic symptoms, aggression, and psychiatric signs in the same residential population.

van den Broek et al. (2006) and Duerden et al. (2012) used similar lab stressors with autistic adults and children. They tracked heart rate and cortisol instead of blood cells. Together the papers build a map: brief controlled events quickly shift biology, and the direction depends on the stimulus you choose.

If you support adults with severe or profound ID, treat a five-minute demand as a medical event, not just a teaching trial. Schedule blood draws, dental work, or room moves after sessions, not during or right before. Offer calming choices like music or outdoor time to reverse the hemoconcentration quickly. Your behavior plan is also a health plan.