According to Piaget, the sensorimotor stage of development is a child’s first stage of development. This stage lasts from birth to 2 years old.
The newborn does not have a well-developed brain, particularly in the frontal cortex. Therefore, the child must develop an understanding of the world through the 5 senses.
Things that occur during the sensorimotor stage – or sensorimotor stage examples – include the grasp reflex, the suckling reflex, prehension, circular reaction, and visual assimilation.
|Child develops object permanence (realizing that objects out of sight still exist), goal-directed action (learning to act intentionally to achieve a goal), and deferred imitation (continuing to imitate others after the event).
|Child develops symbolic thought (using language and signs to represent their thoughts) but remains egocentric.
|Concrete operational stage
|Child develops logical thought and conservation (discovers that changes in appearance do not correspond with changes in weight, volume, etc.)
|Formal operational stage
|Adolescent develops inductive and deductive reasoning. They can use abstract thought and general principles to develop increasingly complex hypotheses.
Sensorimotor Stage Sub-Stages
As the brain matures and neurons develop, so do the child’s abilities. This can be seen in the progression of 6 substages within the sensorimotor stage.
1. Basic Reflexes (0-1 month):
During the first month, the newborn will display several basic reflexes such as sucking and looking at visually captivating images. They will display reflexes in other forms such as crying in response to biological needs that require satisfying and other vocalizations such as babbling.
2. Primary Circular Reactions (1-4 months):
Now the newborn will engage in purposively pleasurable behavior such as sucking their thumb. A baby’s arms and legs will continue to move about in an uncontrolled fashion as neural connections are being formed from the brain to different muscle groups.
They will also orient towards auditory or visual stimuli as their ability to control their eye movements and head continue to develop. In this sense, reflexes become more controlled and purposeful.
3. Secondary Circular Reactions (4-8 months):
The child begins to become more focused on their surroundings and enjoys exploring. This exploration will create unexpected outcomes, which the baby then repeats because it is interesting.
Previously explored connections will also be repeated. For example, a baby will shake a rattle, pause, and then shake it again because it finds the noise stimulating and enjoys creating responses in the environment.
4. Coordination of Secondary Circular Reactions (8-12 months):
The baby’s behavior becomes more intentional. For example, they will purposely reach for desired objects or move an object out of their way to reach a desired toy.
As the prefrontal cortex continues to develop, the baby will demonstrate goal-oriented behavior such as pointing (in the later weeks of this stage). The child’s actions and ability to control their body are becoming more coordinated with their senses.
Object permanence also emerges during this stage. This is the ability of the child to understand that an object sill exists even though it can no longer be seen.
5. Tertiary Circular Reactions (12-18 months):
Experimentation is the hallmark of this stage. The child begins more purposeful experimentation with cause-and-effect relations.
Babies at this age enjoy repeating sequences of actions that create an expected outcome. For example, stacking blocks or rings; taking objects apart and putting them back together.
In addition, the baby also now conducts experimentation to identify novelty. The child no longer simply repeats secondary circular reactions for the sake of repetition, but now purposely initiates variation to discover differences in the outcome.
6. Representational Thought (18-24 months):
This final stage of sensorimotor development marks the beginning of the child being able to form a mental representation of objects.
In previous stages, understanding was bound by physical actions and sensory stimulation. However, in this final stage, we see that the external world is being represented through cognitive constructs.
Sensorimotor Stage Examples (What to Expect)
1. The Sucking Reflex
As Piaget describes in his seminal work, The Origins of Intelligence in Children, basic reflexes are essential to the organism’s survival.
Sucking and grasping reflexes, vocalizations and crying as early forms of communication, movements of the limbs, head and trunk, are all fundamental behaviors that can be observed in infants. They are biologically ingrained and there is little “cognition” involved in their development.
His theory is heavily based on his direct observations of babies and children of various ages. For example, Piaget provides a detailed description of how the sucking reflex has already manifest the day after birth.
In his notes for Observation #2, he writes, “Laurent is lying on his back with his mouth open, his lips and tongue moving slightly in imitation of the mechanism of sucking, and his head moving from left to right and back again, as though seeking an object. These gestures are either silent or interrupted by grunts with an expression of impatience and of hunger” (Piaget, 1936, p. 26).
2. The Reflex Schema
Piaget adopts the notion of a reflex schema and emphasizes its essentiality to the infant’s survival, without ascribing what most of us would consider a “cognition” to this action, even though the term schema is often defined as a mental framework.
However, Piaget used the term to describe reflexes as well. For instance, “The sucking reflex can be conceived as a global schema of coordinated movements…” (p. 35).
As the baby continues to explore its environment, it may put a variety of objects in its mouth to determine if they too can provide nourishment. This is a sucking reflex schema that is in a continuous state of change.
Piaget demonstrated the reflexive nature of the sucking response and provides a detailed description, partially quoted here: “I touch the middle of his cheek with my index finger bent first to the right, then to the left; each time he immediately turns to the correct side…” (p. 29).
3. Circular Reaction: Assimilation and Accommodation
In the stage called Primary Circular Reactions, we can gain a deeper understanding of the chosen terminology by going directly to Piaget’s writings. Again, some explanations of assimilation and accommodation, similar to schema, can sometimes be misunderstood as being purely cognitive.
Piaget highlights a milestone in this stage that involves the intentionality of the infant exploring the environment sensorily:
“…it is one thing to repeat indefinitely a maneuver which has been successful and quite another thing to attempt to grasp an object in a new situation” (p. 49).
The key development is that the reflex is now associated with intent. The intent is to assimilate stimuli from the external world to be made sense of and organized. Hence the term “circular”.
Assimilation then naturally leads to accommodation as new information/stimuli are processed, both biologically and psychologically.
“The repetition of the cycle which has been actually acquired or is in the process of being acquired is what J. M. Baldwin has called the “circular reaction”: this behavior pattern will constitute for us the principle of assimilation sui generis characteristic of this second stage” (p. 49).
4. Visual Assimilations: The Human Face
At the end of the first month, Piaget makes some detailed observations of the infant’s visual tracking abilities and interests. As the visual system develops rapidly during this time, the baby progresses from being passively attracted to stimuli temporarily, to purposively processing specific features.
Piaget painstakingly presents a variety of stimuli to the infant and makes note of the responses. Although some inferences are required because the infant cannot explain themselves, his notes suggest intent.
“Observation 34. His examination of people is just as marked, especially after…his first smiles. When one leans over him, as when dressing him, he explores the face section by section: hair, eyes, nose, mouth, everything is food for his visual curiosity… he alternately looks at his nurse and at me…his eyes oscillate between my hair and face….he looks in turn at his nurse, his mother, and myself with a change of attitude when confronted by each new face and a abrupt and spontaneous moving of his glance from one face to the other” (p. 68-69).
The newborn is captivated by the human face in particular. It is a much more interesting image than other objects Piaget presented, such as a handkerchief or lit match.
5. The Grasp Reflex
The grasp reflex, also called the palmar grasp reflex, is an involuntary response to the palm being pressed lightly. There are two components to this response: one is the closing of the fingers around the object, and the second is the clinging, which is actually strong enough to hold the baby’s weight.
The palmar reflex can be demonstrated just hours after birth, but will start to fade around the age of 2 or 3 months. After three months, some babies will still struggle to firmly grasp and hold on to soft objects. This is quite normal and so there is no need to worry.
Regular examinations by a pediatrician will involve appropriate assessments and normative comparisons for the baby’s age and gender which will ensure that any issues are identified.
Of course, there are lots of ways for caregivers to facilitate this key developmental milestone. Baby gyms and soft toys are available in most toy stores.
These items offer great opportunities for a baby to attempt to reach for and grasp a variety of visually and tactilely stimulating objects.
6. The Emergence of Deliberate Action
“With the mouth, the eye, and the ear, the hand is one of the most essential instruments of which the intelligence, once it has been established, will make use” (Piaget, 1936, p. 88).
The ability to hold objects of interest, (thank you, opposable thumbs), is considered one of the key factors that facilitated human intelligence. Few other species have this digit, and humans have made use of it in meaningful ways.
Voluntary grasping quickly becomes an early manifestation of deliberate action, around the age of 2 months according to Piaget.
In his words: “…the definitive conquest of the mechanisms of grasping marks the beginning of the complex behavior patterns which we shall call “assimilations through secondary schemata” and which characterize the first forms of deliberate action” (p. 88).
This is a key milestone in cognitive development, which although takes place in the sensorimotor stage, is much more than just a sensory experience. It is an indicator of intent, a cognitive construct.
7. Prehension: Stages Two and Three
Prehension is defined as the act of taking hold, or grasping. It derives from the Latin verb prehendere. Modern descendants of the word include comprehend (to grasp the nature or significance of).
Based on his observations, Piaget identified at least 5 stages of prehension.
Stage 1 includes the involuntary grasp reflex, while stages 2 and 3 represent the emergent coordination between the visual and motor cortex. This is a key development, although not as straightforward as we might prefer.
For example, in stage 2 “…the glance already follows the hand movements but the latter are not governed by the former” (p. 102).
This means that the infant can track the movement of their hands as long as they are in their visual field, but the hands seem to have a “mind of their own”. The hands often move outside the visual field, which implies they are not under control of the visual system.
Although the coordination between the eyes and the hands is progressing, the degree of this coordination is very limited.
“It is not yet possible to speak of coordination between vision and prehension, since the child knows neither how to grasp what he sees…nor how to hold before his eyes that which he has grasped…” (p. 106).
8. Means to an End
There is an important distinction between a primary circular reaction and secondary ones. That distinction lies in the fact that secondary reactions are a result of purposeful experimentation. The actions are engaged in order to see a result.
In Piaget’s own words: “the movements are centered on a result produced in the external environment and the sole aim of the action is to maintain this result; furthermore it is more complex, the means beginning to be differentiated from the end” (p. 157).
In Observations 94 and 95 (pp. 157-159), Piaget describes in detail his experimentation with Lucienne. First, he observes that while lying in her bassinet, she causes the cloth dolls attached to swing. She finds this enjoyable and smiles.
But, Piaget points out that he cannot yet infer intent, or that she has enacted with the goal of a means-to-end purpose.
Over the next couple of months, he presents different scenarios using different dolls, placing the dolls in different locations on the bassinet, changing bassinets, and using other objects such as puppets.
Each time, he observes Lucienne engaging in the same sequence of experimentation, she kicks her feet to make the objects move. She pauses, then repeats. She often looks intently as though studying this cause-and-effect connection between her actions and response of the external world.
Piaget is convinced; he concludes that she is exhibiting secondary circular reactions.
9. The Scientist Emerges
Piaget labels the tertiary circular reactions stage as representing a profound advancement in the child’s cognitive development. In fact, he describes this stage as the “discovery of new means through active experimentation” (p. 267).
The distinguishing factor between secondary circular reactions and tertiary reactions is that now the child slightly alters repetitive acts to see variation.
Much like the scientist manipulates the level of the independent variable (IV) to observe changes in the dependent variable (DV), so does the emerging toddler.
Piaget’s description of Laurent’s behavior is illuminating:
“At 0;10 (11) Laurent is lying on his back but nevertheless resumes his experiments of the day before. He grasps in succession a celluloid swan, a box, etc., stretches out his arm and lets them fall. He distinctly varies the positions of the fall. Sometimes he stretches out his arm vertically, sometimes he holds it obliquely, in front of or behind his eyes, etc. When the object falls in a new position (for example on his pillow), he lets it fall two or three times more on the same place, as though to study the spatial relation; then he modifies the situation” (p. 269).
“The child discovers in this way that which has been called in scientific language the “experiment in order to see” (p. 266).
10. Systematic Intelligence
The final development in the sensorimotor stage is distinctly and qualitatively different from previous sensory-based explorations. Now Piaget talks about a systematic intelligence; one that involves mental representations of the external world and the ability to create “invention” by constructing mental combinations.
The terminology may be unfamiliar and difficult to decipher, but Piaget is describing the child’s ability to think at a much more advanced level than in the previous stage.
An exert from his notes may help:
“I then put the stick between him and the bread…Laurent again looks at the bread, without moving, looks very briefly at the stick, then suddenly grasps it and directs it toward the bread. But he grasped it toward the middle…so that it is too short to attain the objective. Laurent then puts it down and resumes stretching out his hand toward the bread. Then…he takes up the stick again, this time at one of its ends (chance or intention?), and draws the bread to him” (p. 335).
The child has used an object in a novel way to reach a goal. From a Piagetian perspective, this is an advancement in cognitive development that represents a sophisticated mental operation.
Piaget developed an incredibly insightful theory of cognitive development. His methodology involved direct observation of babies and toddlers which included a little bit of trial and error and a lot of intuitive insight.
His theory identifies the stages that all humans go through, from fundamental sucking and grasping reflexes to eventually using objects in novel ways as a means to an end; all by the age of two years old.
The best way to understand the Piagetian perspective is go directly to the source. His book, The Origins of Intelligence in Children, gives the reader a first-hand account of how he developed one of psychology’s most influential theories.
Bibace R. (2013). Challenges in Piaget’s legacy. Integrative Psychological & Behavioral Science, 47(1), 167–175. https://doi.org/10.1007/s12124-012-9208-9
Beilin, H., & Fireman, G. (1999). The foundation of Piaget’s theories: Mental and physical action. Advances in Child Development and Behavior, 27, 221–246. https://doi.org/10.1016/s0065-2407(08)60140-8
Göncü, A., & Gaskins, S. (2012). Comparing and extending Piaget’s and Vygotsky’s understandings of play: Symbolic play as individual, sociocultural, and educational interpretation. In P. E. Natahn & A. D. Pellegrini (Eds.), The Oxford Handbook of the Development of Play (pp. 48-57). Oxford University Press. https://oi.org/10.1093/oxfordhb/9780195393002.013.0005
Müller, U., & Liben, L. S. (2015). The development of executive function. In R. M. Lerner, L. S. Liben, U. Mueller, R. M. Lerner, L. S. Liben & U. Mueller (Eds.), Handbook of Child Psychology and Developmental Science, Cognitive Processes (pp. 571-613). Somerset, England: John Wiley & Sons, Incorporated.
Rousseau, P. V., Matton, F., Lecuyer, R., & Lahaye, W. (2017). The Moro reaction: More than a reflex, a ritualized behavior of nonverbal communication. Infant Behavior and Development, 46, 169-177.