The Body Language Of Pointing – Human Infants Point To Manipulate, Apes Point To Reach
Christopher Philip
Pointing seems like the most basic and simplest of body language. We point because we want something, “imperative pointing,” or when we want to share attention with something at a distance, “declarative pointing.”
It is also widely believe that imperative pointing, for wanting something, is simpler than declarative pointing, to share attention.
This is thought to be the case because we see imperative pointing early in infancy and it is commonly seen as resembling open handed reaching rather than index-finger pointing. Children with autism also do not seem to point declaratively, but do still do so imperatively.
Captive great apes also do not point with one another, however, captive great apes do point declaratively for humans in an imperative attempt to request objects.
The difference relies on the thought that imperative pointing is simply ritualized reaching, a simple process, whereas declarative pointing is a shared mental state.
However, even reaching for an object in view of another implies that the other will share in the understanding that a desire exists. Thus, there seems to be a decoupling of real action. Asking for an object does not require acting out the message – simply direct gaze is enough to signal a “cooperative request.”
However, when pointing arises in children at 12 months of age, what concepts are they following?
Are they communicating a simple request or are they seeking to cooperate?
What we know about apes will help us draw conclusions. Apes are often observed in captivity pointing at objects they desire, even banging and vocalizing. They may even point with the index finger. This makes the pointing of apes similar to imperative pointing of infants.
That being the case, how does infant gesture originate? Does it arise through evolutionary history or is it a real difference in nonverbal communication?
When pointing arises in apes and infants, it is usually the result of certain constraint. For example, a child might be confined to a highchair whereas an ape might be confined to a cage.
To shed more light on the origins of pointing in apes and human infants a team of researchers Marloes van der Goot, Michael Tomasello and Ulf Liszkowski designed an observational study.
The study had infants and apes constrained by caging for which a desirable item was placed out of reach. Despite this, the infants and apes were free to move around proximally.
The experiments wanted to see if the infants and apes would point from where they were located (centrally) or approach the item as close as possible before signaling their attention for the item. In another part of the experiment, infants were tested on whether they would point to an object they desired or physically approach the object themselves if no constraint was present.
Results showed that the apes always approached the object before signaling their request through instrumental actions. In contrast, infants quite often stayed back at a distance and directed the experimenter’s attention to the desired object. This was usually done through index finger pointing. This occurred even in the condition where the infant was not constrained and could easily approach and collect the object themselves.
The results suggest that the “lean hypothesis” is in fact correct with respect to apes. Apes signal requests through instrumental actions; they lean in to try to get the object themselves and when that fails, they continue to reach resulting in pointing. Infants, on the other hand, use higher order thinking and actually point in order to communicate nonverbally that an object is desired. Overall, the data suggests that infants can choose which strategy they wish to use when an object is desired. They may approach the item themselves or communicate their desire through pointing.
The researchers summarize the findings as such:
“This study demonstrates that when 12-month-old infants point to request they communicate on a cooperative level, independent of environmental constraints, and not through instrumental action patterns, like reaching. The study also demonstrates that nonhuman primates do not request in this way. Instead, they make their intention to obtain an item apparent through the instrumental action patterns of obtaining it.”
This study is a clear demonstration that humans use gestural nonverbal communication, pointing specifically, on a whole other level than that used by our next closest relative. Humans use pointing not only to get access to desirable objects, but also to draw in and share attention with others in a more meaningful way. By 12 months of age, infants have also developed expectations that pointing will not only draw attention in a specific location, but will also produce compliance and cooperation from a confederate.
Image Credit: a2gemma
Resources
van der Goot, Marloes H.; Michael Tomasello and Ulf Liszkowski. Differences in the Nonverbal Requests of Great Apes and Human Infants. Child Development. 2019. 85(2): 444–455.