Sensitive Periods

Sensitive periods is a term coined by the Dutch geneticist Hugo de Vries and adopted by the Italian educator Maria Montessori to refer to important periods of childhood development.

Montessori believed that every human being goes through a series of quantum leaps in learning during the pre-school years. Drawing on the work of de Vries, she attributed these behaviors to the development of specific areas of the human brain, which she called nebulae. She felt this was especially true during the first few years of life, from birth (or before) to the time of essentially complete development of the brain, about age 6 or 7. Montessori observed several overlapping periods during which the child is particularly sensitive to certain types of stimuli or interactions. She describes these as "sensitive periods", a phrase coined by de Vries during his studies on animals.

According to Montessori, during a sensitive period it is very easy for children to acquire certain abilities, such as language, discrimination of sensory stimuli, and mental modeling of the environment. Once the sensitive period for a particular ability is past, the development of the brain has progressed past the point at which information can be simply absorbed. The child must then be taught the ability, resulting in expenditure of conscious effort, and not producing results as great as could be produced if the sensitive period had been taken advantage of. Montessori was not very specific in her published works about the precise number, description, or timing of these sensitive periods. However, in her lectures to teacher trainees she set out several periods with the approximate ages to which they applied. More importantly, she believed, adults should observe the behavior and activities of children to discover what sensitive periods they are in.