Not so, says Goupil. She thinks that these early results said more about the experiments than the infants. Perhaps the tasks were just too hard and the children “couldn’t report if they were sure or unsure because they were just confused all the time,” she says. “And maybe they’re bad at talking about their own mental states, but can reflect on their own competencies and knowledge if you ask them to do so non-verbally.”
So she designed a simple wordless experiment. Her team invited 80 Parisian parents to bring their 20-month-old infants to a lab, where Romand-Monnier played with them for a few minutes. She then hid a toy in one of two boxes, either in full view of the infant or behind an obscuring curtain. After a pause of 3 to 12 seconds, she asked the baby to point to the box that the toy was in. Half the babies did so unaided. The other half had the option of silently asking for help from their parents, by turning to them and making prolonged eye contact.
The team found that the infants asked for help more often when the task was harder—when the memorization gap was longer (12 seconds versus 3 seconds), or when the toy was being hidden behind a curtain. And because of that, they got better results: The two groups of infants made the same number of right guesses, but those who could ask for help made far fewer wrong guesses. By correctly gauging their own uncertainty, they avoided errors by asking for help, and so improved their performance.
“They didn’t just constantly ask for help, but only when the task was difficult,” says Uta Frith from University College London, who was not involved in the study. “You can infer from this that they were ‘aware’ that: a) they couldn’t do the task; b) that someone else could do it; c) that that person would be able to tell them how to do it. So it’s a whole lot of useful information that these babies compute.”
Scientists have used similar tests to investigate if animals like monkeys, rats, and honeybees also have metacognition. But the results of these studies are controversial and fiercely debated. The animals in question are often extensively trained to perform the tasks in the experiments, so skeptics suggest that they have simply learned to, say, seek help on difficult trials.
That can’t be the case for Goupil’s infants. “It’s unlikely they could learn precise contingencies,” she says, since each of them only experienced two training trials and ten actual ones. They also didn’t get any better with time, which suggests that they weren’t simply learning how to do better in the study. Instead, the team writes, they can “communicate metacognitive information to others,” which suggests that “they consciously experience their own uncertainty.”
But here’s the thing, says Frith: The infants only showed metacognition when they were told they could ask for help. “I would not have predicted that a clue would be necessary,” she says. Perhaps that’s how the skill develops. At 20 months, infants have it but it’s latent, and they need a nudge to use it. Later, they wield metacognition more readily. And after four years, as per earlier studies, they understand what they’re doing enough to talk about it.