Infant Development: Chapter 2: Motor development and Psychosocial Development

When you see your infant squirming around and kicking at the air, do you sometime wonder what exactly they are trying to accomplish? Or perhaps you wonder why they crawl and go...backwards!? Why do they do this? When will they learn to walk? To crawl? Read on, and these and other questions will be answered.

Motor Development

0-1 Month

In the beginning, reflex is the only thing a baby has. Reflexes are just unlearned, involuntary responses that automatically are triggered with the occurrence of certain stimulus, and in general serve some sort of survival function. Among these reflexes are crying, rooting, and sucking. Also, it should be noted that at this stage, the infant has no object permanence, so if their toy falls to the ground out of sight, they no longer see it in front of them and feel that it is gone forever. It is not a permanent object in their universe. This happens with people as well, which is why an infant should have plenty of contact by their parents.

1-4 Months

Around this time a baby will start adapting their reflexes to their environment, such as throwing their pacifier, or batting away a bottle. Also, you will begin to see smiling, cooing, other baby noises, and they will look at you. This is a wonderful period for the parent, being able to see your baby smile and look into your eyes is a wondrous thing. At this stage they will not search for an object outside of their field of vision, but object permanence is slowly developing.

4-8 Months

It is in this stage that a child begins to be more responsive, intentionally grabbing things, holding, and even learning how to take turns with objects. Also, they will begin babbling to people that they know, and momentarily search for objects outside of their immediate field of vision.

8-12 Months

This is when the infant has a more purposeful response, and can begin to anticipate events. They will also begin to respond to language at this stage, and will actually start speech. The impulse to find their toy becomes more active.

12-18 Months

At this time, the baby will become more active and creative in exploring their environment, and will go through various trial and error to discover things. Generally there will be questions and comments from the baby, often using one word to encompass an entire idea or thing. Also, by now, the baby can find objects that it had temporarily lost.

18-24 Months

A child in this stage can now figure events out in its environment, can solve mental combinations and puzzles, and will begin play acting (dressing up in mothers/fathers clothing, etc). They will by now have an expanded vocabulary, and their object permanence is now fully developed.

Gross/Fine Motor Skills:

Infants do not have enough control over their bodies in the earlier stages to perform delicate tasks, but they can accomplish some movement. You will often see infants trying to lift their heads, and as they get stronger, they will push against the objects they are on, in an effort to move themselves. Many times they will actually end up pushing themselves backwards, but generally by six months, they are able to move themselves in particular directions. As a child grows and develops, they begin to cultivate fine motor skills, which are improved gross motor skills (which begin to manifest themselves around 3 motnhs of age), such as sitting upright, and being able to coordinate the movement of their limbs. They are able to perform much more delicate motions, such as grasping. Here is a brief list of some motor development milestones (source: Adapted from Frankenburg et al., 1992)

(Note: 50% of children are able to perform each skill at the month indicated in this list. However, the exact timing when each skill appears does vary.)

3 Months: Opens hand prominently

3.2 Months: Rolling over

3.3 Months: Grasping rattle

5.9 Months: Sitting without support

6 Months: Able to propel themselves in desired direction

8.2 Months: Grasping with thumb and finger

11 Months: Holds crayon adaptively

11.5 Months: Standing alone well

12.3 Months: Walking well

14.8 Months: Building tower of two cubes

16 Months: Places pegs in board

16.6 Months: Walking up steps

23.8 Months: Jumping in place

24 Months: Imitates strokes on paper

33 Months: Copies circle

Please remember that the timing of all of these milestones are based on norms ( an average performance of a large sample of children of a particular age). Perfectly normal children may be a bit behind the norm, but the parent should not be overly concerned.

Psychosocial Development

Psychosocial development is the development of a persons understanding of the environment they are living in, and figuring out how that relates to them, their behavior, and others. To put it in even simpler terms, it is learning about yourself, through your surroundings and other people.

Erik Erikson developed a theory of psychosocial development which considered how an individual would come to understand themselves and interpret the meaning of their own behavior, and that of others. The theory states that there are eight stages of developmental change through ones life, and the first start in infancy. The first stage he presented was the trust-versus-mistrust stage. This takes place during the first 18 months of life, and is when an infant will either develop a sense of trust or mistrust, depending on how well their needs are satisfied by those caring for them. Erikson suggests that if an infant is able to develop trust, they also develop a sense of hope, which allows them to feel like they can meet their needs successfully. On the other side of the coin lies mistrust, which can lead an infant to see the world as a hard and unfriendly place, and may later in life have difficulty forming close relationships with others.

Towards the end of infancy, a child enters into the autonomy-versus-shame-and-doubt stage, which is from 18 months to 3 years. During this stage, the child will develop independence and a self reliance which will encourage them to explore and feel freedom within safe boundaries. However, when children are over protected and sheltered, or overly restricted, they will feel shame and express self-doubt and unhappiness.

There are two other theorists on this subject, Margaret Mahler and Mary Ainsworth. Mahler stated that from birth to about 2 months, a baby is in a state of natural autism, and such is not developing any personality. At about two months, the child goes through the symbiosis stage, in which they develop a symbiotic relationship with their mother. The third stage is at 5 months, in which the child goes through the separation-individuation stage, in which they begin to establish themselves as a separate entity from their mother, and will begin to develop their personality.

Ainsworth comes in with his theory, stating that through infancy, a child will feel comfort and security while around their parents, and face some discontent when away. Depending on the outcome of their upbringing (very nurturing parents vs. more apathetic), a child will be either secure, insecure, avoidant, or ambivalent. The overly dependent children will stay with their mother and not explore, the more secure children will feel much more secure in their surroundings and feel more freedom to explore. This theory most parallels Erikson’s in my own opinion.

Go back to Infant Development: Chapter I ----------------------------------------------------------------------------------------------------------------------------------------------Go forward to Infant Development: Chapter 3


Lecture notes from my Developmental Psychology class taught by S. Harrison, 9-18-2002, Evergreen Valley College, San Jose, California.

Feldman, S. Robert. Development Across the Life Span (3rd Ed). Upper Saddle River, New Jersey: Pearson Education.