Learning to sit, crawl, and walk are all major milestones in a child’s early development – and parents often record these actions in baby diaries, photographs, and videos. The development of motor skills allows the child to become more independent. But our research, supporting a number of other studies, has shown that they can also tell more about a child’s rate of cognitive development, such as speaking.
It makes sense that the ability to move around affects the way children see, think, and talk about their physical and social surroundings. Indeed, in recent years it has become increasingly clear that cognitive development is more closely related to the development of gross motor skills, such as crawling or walking, and fine motor skills, such as grasping and handling objects, than many. never thought so before.
In fact, it has been suggested that instead of separately assessing motor and cognitive development, they should be viewed as two cogs connected within a large and complex system, each dependent on each other. and working together to take small steps forward in development.
It is therefore essential that more research study the relationship between motor and cognitive development, rather than focusing on the latter as separate parts. This will not only be important for understanding typical development, but could also help explain the difficulties some children face when connections in the system are disrupted.
Learning language is a very long process for infants. They have to go through a period of learning how to use their mouths to make sounds, such as blowing raspberries. Then there is the babbling. Then comes the first word. Finally, children are able to construct sentences and, later, have conversations.
Research has shown that before each of these language milestones, there is usually a change in motor actions. One example is babbling, where a child repeats the same sound over and over (“bababa”). In the first few weeks before babbling begins, infants exhibit many arm movements, such as hitting, shaking, or waving. The interesting thing is that after starting to babble, infants stop making these movements so much.
Why would these two activities be linked? Both may let infants see what happens when an action is repeated, so they get used to the sounds and sensations in their body. Infants learn that something they do causes something else. It’s like learning that when you press a button, a light comes on.
There are many other examples of new motor and language skills emerging around the same time. The fact that the motor action and the language milestone are so close in time suggests that the two parts of the system are developing together.
Our own research has focused on what happens when infants have difficulty developing their motor skills in typical ways. One way we’ve done this is to examine the relationship between motor and cognitive skills in autism spectrum disorders (ASD).
Language and communication problems are essential for a diagnosis of ASD, but children with ASD often also have difficulty with motor skills. We conducted a study of 53 infants whose older siblings had ASD. This increases the risk that they themselves will develop ASD.
Working with the British Autism Study of Infant Siblings (BASIS) in Birkbeck, we found that these infants generally had lower motor skills by the age of seven months compared to infants who had an older sibling without an ASD. Importantly, we have shown that motor skills at seven months predicted the rate of language development in the group of infants who developed ASD on their own. This suggests that early poor motor skills could be a factor affecting the development of language difficulties, and that this could be particularly relevant for those at risk of developing ASD.
We are also studying the cognitive skills of children with developmental coordination disorders (CDD), diagnosed on the basis of motor difficulties that have an impact on daily life. We hope that these studies will help us better understand the relationships between motor and cognitive development.
An important point to remember in this discussion is that children develop naturally at different rates. An infant can start crawling at any time between five and 13 months of age and still be in the expected age range for crawling. Some infants don’t crawl on their hands and knees at all, but rather drag, crawl, or just start walking so they can move around the room.
This means that parents shouldn’t worry that their child will not be “smart” or not develop well if they are not crawling early. Crawling is one way to solve a problem, like reaching for a toy across the room, but it’s not the only one. As a child’s body grows and their muscles strengthen, better ways to deal with these issues develop.
A future question for study will be whether there are critical periods in the development of these skills which result in atypical development in some children. It will also be important to determine the different pathways that motor and language skills can follow. To answer these questions, future research will need to study children over time and study the two skill sets together.