Down syndrome is associated with a lack of which type of muscle recruitment?

• A. Selective
• B. Global
• C. Simultaneous
• D. Sequential

Answer: (A)

Selective motor control is the ability to activate specific muscles for a task while not activating others. In Down syndrome, this control is often reduced due to hypotonia and motor planning differences, so movements rely less on isolating targeted muscles and more on broad, non-specific muscle activation. That means there’s a lack of selective recruitment—co-contraction or diffuse usage of many muscles rather than precise, isolated activation.

For example, skilled finger individuation or precise hand shaping is harder because the muscles aren’t recruited in a highly selective way; instead the whole hand or large muscle groups may kick in. Clinically, this explains why therapy focuses on neuromuscular re-education and tasks that promote isolated activation and better motor planning, rather than simply increasing overall strength.

Other patterns like recruiting many muscles simultaneously or in a strict sequence aren’t the hallmark feature here; the defining issue is the difficulty about isolating the intended muscles, hence selecting the appropriate option.