Sensitive Periods of Human Development

The Dutch biologist Hugo de Vries was one of the first to notice “sensitive periods in development” when he referred to a species of caterpillar.  The baby caterpillars have a special sensitivity to light, which when they emerge from their eggs on the trunk of the tree, causes them to be drawn to the tips of […]

September 1, 2019

The Dutch biologist Hugo de Vries was one of the first to notice “sensitive periods in development” when he referred to a species of caterpillar.  The baby caterpillars have a special sensitivity to light, which when they emerge from their eggs on the trunk of the tree, causes them to be drawn to the tips of the branches where they can eat the new, tender buds.  The caterpillars lose this sensitivity when they are bigger and stronger and are able to eat the tougher, older leaves.  It is interesting that the disappearnce of this sensitivity is as important as its presence.  Montessori pointed out that conditions extremely favorable to development at one stage may become unfavorable at a later one.

Montessori philosophized that similar things happen in childhood and now contemporary research shows that children indeed pass through certain critical periods that are conducive to developing specific skills: windows of opportunity during which the brain is particularly efficient at specific types of learning.  That is why at particular times they show intense, overwhelming interest in certain objects and activities, which at a later time, will be quite boring.  It is as if a burning passion urges them to focus attention to the exclusion of others.  When a sensitive period is at its height, it is as if a spotlight illuminates some things while others are in the shadows.  Under this fascination, children will work long periods without fatigue and will not feel tired, but refreshed.

One of the most interesting periods is that for language acquisition.  It begins at birth and is intense until about 7 years old.  Babies love to hear the human voice and will listen attentively, tuning out other sounds.  Montessori teachers are very careful to present materials without talking because children instinctively look at their mouth rather than the demonstration. Abused children who have little communication with adults never develop good vocabularies.  Learning a foreign language is much more difficult after age 7 and can be drudgery after 12.  By then the sensitive period is well and truly over and the child is embarking on a different kind of learning.

The sensitive period for language has social implications too.  The languages of the world can only survive if they are learned by babies and attempts to revive dead languages are not usually successful for this reason.

Another fascinating sensitive period is that of order.  This appears about two years of age and lasts until about age four.  It is a difficult time for parents who do not understand it and is probably the cause of most temper tantrums.  During this period children exhibit a passionate interest in the order of things.  Children have a real obsession that everything be kept in its proper place and that everything happens at its proper time.  Children drive parents crazy with their love of rituals.   Let the furniture be changed around, a new picture appear on the wall, or their place at the table changed and your child will notice immediately, and possibly turn into a tyrant.  It is sometimes hard for the adult to fathom out what has caused the child to become so bent out of shape.

Even though adults are distressed by disorder, we are mainly concerned with how it affects our comfort and efficiency; we are not constructing our intelligence by it.  A teenager will have already sorted out hundreds of experiences, and filed everything in memory to draw upon to help understand the world.  Children start out with a chaos of images but the sorting process is built in and must be completed so that foundation is firm.  We can help at home by acknowledging this need and by keeping as much continuity as possible during this time.  Even though children are particular about how a placemat should be put in front of them, their ability to keep order is not good.  However, they enjoy the process and can help to keep their room in order if given small isolated tasks to accomplish. Keep it simple and fun.  In this way, it will become a lifelong habit.

In school, order is important.  Everything has its place and because of this sensitive period, children quickly form a memory of the position of the materials in the classroom.  They take tremendous delight that things are always in the same place and love to tell you where everything goes.  Without this sensitive period for order, it would be quite impossible to give a class of preschool children the freedom of a Montessori classroom.

The sensitive period for justice comes in about six years old and continues intensely for several years.  These are the years when every child has to be given exactly the same size scoop of ice cream because otherwise someone will notice instantly and either gloat or feel slighted.  Children can be terribly unfair to each other at this stage but have an insatiable need to debate that things be seen to be fair.

There are other sensitive periods but it is useless to try to make up for the sensitive period once it has passed.  We have missed the bus.  It is possible to learn a foreign language when we are older but it is hard work, not pure delight.  It is a joy for the three and four year old to know the names of the geometric shapes they see every day when they are in the sensitive period for enjoying shapes and words, but it is such a chore for the older child to have to learn them.

Children live in the present and are totally engulfed by their sensitive periods.  Be reassured that the obsessions of the moment are not permanent, but each one has a purpose and a time and its effects add to the foundations of a lifetime.

Sensitive Periods:

Young children go through “sensitive periods” when they are more receptive to learning a particular skill.  Sensitive periods do not necessarily come at precisely the same time in each child’s life, but all children experience them.  It is important for parents and teachers to be aware of these phases so they may better understand the child.  They can then support the child in his/her all-consuming desire to absorb a particular concept or learn and practice a particular skill during these times.  Once these sensitive periods are over they will never return.  The child will still learn but not with such ease and intensity as before.

The following is a general guide to the times when a young child can best learn specific skills and concepts; they do not always apply to individual children:

  • birth to 3 – sensory experiences
  • birth to 1-½ – learning through movement
  • birth to 7 – development of language
  • 1½ to 4 – development of muscular coordination
  • 2 to 4 – concern with order in the environment and routines
  • 2 to 6 – refinement of senses, development of social skills
  • 3 to 6 – sensitivity to adult influences
  • 3½ to 4½ – writing
  • 4 to 4½ – sense of touch
  • 4½ to 5 – reading
About the Article’s Author: Joan Starling, Founder, Sammamish Montessori School serving preschool and kindergarten students in Redmond WA.  
Joan established The Sammamish Montessori School in 1977.  She began her long career in Montessori education more than 4 decades ago being taught by two Montessori trainers who were themselves taught directly by Dr. Maria Montessori. One of them, a wise and practical woman, Margaret Homfray, accompanied Dr. Montessori on trips to translate her lectures on her speaking tours in the 1930s.  Joan has been a pioneer of Montessori education in the greater Seattle area, establishing one of the oldest Montessori schools on Seattle’s Eastside and now one of the largest Montessori schools in the state.  Joan is enjoying her well-earned retirement. Her two daughters, Janet and Hilary, now share the running of the school and are supported by a wonderful group of exceptionally talented, well educated, experienced teachers, assistants and supporting staff who have come from all over the world. 


Sammamish Montessori School