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Pointing: Reference and Context

From around 11 or 12 months of age, humans spontaneously use pointing to ...

  • request
  • inform
  • initiate joint engagement (‘Wow! That!’)

Why is this significant? Because it implies two things: First, it implies that infants' pointing is referential communication; that is, communication about an object. (Contrast sharing a smile; we're communicating, but not necessarily referring.) Second, it implies that infants have some understanding of joint engagement.

How do infants understand pointing actions?

Explain this in terms of models.

Hypothesis 1: Pure use (compare block & slab).

‘Let us imagine a language for which the description given by Augustine is right. [...]

A is building with building-stones: there are blocks, pillars, slabs and beams.

B has to pass the stones, and that in the order in which A needs them.

For this purpose they use a language consisting of the words ‘block’, ‘pillar’, ‘slab’, ‘beam’.

A calls them out; B brings the stone which he has learnt to bring at such-and-such a call.’

Wittgenstein (1953, §2)

Can we think of infant pointing on this model, just as a bit more sophisticated in that the pointing gesture picks out different objects on different occasions?
What are the limits of this picture? (a) there is a fixed thing that people do in response to pointing. (b) the context of the activity in which the pointing occurs is fixed (it’s building).
The \emph{block--slab} model of infant pointing \citep[compare][§2]{Wittgenstein:1953mm}: (a) the activity occurs in a fixed context (e.g. buliding) and (b) there is a fixed thing to be done in response to a point.

How do infants understand pointing actions?

Hypothesis 1: Pure use (compare block & slab).

Do you think the pure use (block and slab) hypothesis is plausible? Why?

From around 11 or 12 months of age, humans spontaneously use pointing to ...

  • request
  • inform
  • initiate joint engagement (‘Wow! That!’)

Let's have a look at the evidence for informative pointing.

Liszkowski et al 2008, figure 3

Liszkowski et al 2008, figure 3

Liszkowski et al 2008, figure 5

Subjects are 12-month olds. Fig. 5. Experiment 2. Mean proportion of trials with a point in the experimental (E is ignorant) and control (E is knowledgeable) conditions.

From around 11 or 12 months of age, humans spontaneously use pointing to ...

  • request
  • inform
  • initiate joint engagement (‘Wow! That!’)

Why is this significant? Because it implies that infant pointing is not just a matter of getting you to do things for the infant, nor of getting you to do things with the infant. Instead it can be used where the infant has no expectation that you will do anything with or for the infant. And this matters because it constrains how an infant could understand pointing.

How do infants understand pointing actions?

Hypothesis 1: Pure use (compare block & slab).

The fact that infants can point to request, inform and initiate joint attention shows that the simple block & slab model is wrong because that is a model where communicative actions have a fixed purpose, and pointing does not. It seems to rule out the block & slab model.
Recall that there were two limits on block & slab: (a) fixed purpose and (b) fixed context. We've seen that (a) pointing does not have a fixed purpose. What about fixed context? A further finding bears on this ...
I want to say a tiny bit more on what is involved in understanding a pointing gesture. Suppose that we are doing puzzle. Then if I point to a piece, I probably intend you to do something with it in the context of our activity. By contrast, if we are tidying up, a point to the same object might mean something different. So:
Comprehending pointing is not just a matter of locking onto the thing pointed to; it also involves some sensitivity to context \citep[see][]{Liebal:2010lr}.
This is nicely brought out in a study by Christina Liebel and others ...
\subsection{Pointing: referent and context}

pointing: referent and context

Liebal et al 2009, figure 1

Liebal et al 2009, figure 2

18-month-olds can do this, but 14-month-olds can't. (Don't infer anything from null result.)

Liebal et al 2009, figure 3

Liebal et al 2009, figure 4

Here are the results of another study from the same paper, Study 2. ‘In this study, in each of two conditions infants shared a clean-up game involving multiple different objects with an experimenter (E1). At the end of this game, depending on the condition, either E1 or a different experimenter (E2), with whom infants had not shared any relevant experience, pointed toward a new object. If infants understood the situation correctly, they should clean up this new object when E1 pointed but not when E2 pointed.’
On this simplified measure, the results show that 14 month olds are interepreting pointing in context.
‘Already by age 14 months, then, infants interpret communication cooperatively, from a shared rather than an egocentric perspective’ \citep[p.\ 269]{Liebal:2010lr}.
‘The fact that infants rely on shared experience even to interpret others’ nonverbal pointing gestures suggests that this ability is not specific to language but rather reflects a more general social-cognitive, pragmatic understanding of human cooperative communication’ \citep[p.\ 270]{Liebal:2010lr}.

How do infants understand pointing actions?

Hypothesis 1: Pure use (compare block & slab).

Recall that there were two limits on block & slab: (a) fixed purpose and (b) fixed context.
Since infant pointing is subject to neither fixed limit, that can't be how infants understand pointing.
Let's see what the experts say about how infants understand pointing ...