Reactive postural control is defined as responses to perturbations that are

• A. Predictable perturbations
• B. Unexpected external perturbations
• C. Under conscious planning
• D. Habituated responses

Answer: (C)

Reactive postural control involves rapid, automatic corrections that occur after a destabilizing event. These responses are driven by sensory feedback and are not consciously planned in advance. They are triggered by perturbations that are unexpected or unpredictable, so the system can’t pre-program the exact adjustment and must quickly recruit reflexive and automatic pathways to restore balance.

This stands in contrast to anticipatory (proactive) adjustments, which are planned before a known movement or perturbation to prevent loss of balance. Habituated responses describe learned changes with repetition, which can modify how we respond, but the essential idea of reactive postural control is the automatic response to an unforeseen disturbance, hence the focus on unexpected external perturbations.