Sensory integration disorder is not a disease. Children with high IQ will also have sensory integration disorder. Simply put, it is the ability of the child's nervous system to coordinate and control various body senses. This ability is not born, but acquired through continuous learning. The most critical period of sensory integration learning is before the age of 7, because during this period, people's brains develop very fast. In many sensory integration, the phenomenon of writing words backwards belongs to "vestibular feeling"