The first level of self-development is called sensoriphysical structure; it is the structure that deals with the material component, sensation and perception. An infant is primarily at this level with the start of understanding and development of senses and perceptions.

Most words trigger a response from our neurological system and it is a function of various factors that are different for different individuals, they could include and are certainly not limited to culture, upbringing, environment, physical and emotional state etc.