Sensory Motor Amnesia (SMA) is a condition identified in Hanna Somatic Education where the brain loses voluntary control and full awareness of certain muscles because they have become habitually tight and contracted over time. It happens when repeated stress, injury, emotional tension, or long‑held postures lead the nervous system to keep sending “tighten” signals. Eventually the brain gets used to this state and “forgets” how to sense and release those muscles, so chronic tightness and pain persist even when the original cause is gone.
In somatic theory, this isn’t a structural injury but a learned neuromuscular pattern: the sensory‑motor system becomes stuck in a habitual reflexive state, and voluntary control from the sensory‑motor cortex diminishes. Because muscles only move when the brain sends the signal, SMA means the brain no longer consistently registers or allows relaxation of those muscles.
SMA can lead to chronic muscle tension, limited mobility, poor posture, shallow breathing, joint stiffness, and pain. Somatic movement practices aim to reverse SMA by restoring sensory awareness and voluntary control of muscles through mindful, slow movement that re‑establishes communication between the brain and the body.
Resources :
Clinical Somatic Education – An Introduction
Lawrence Gold, Hanna somatic educator