Humans are masters of metacognition: thinking about thinking. We can evaluate what we know and what we don't know. If you don't know how to get somewhere, you Google directions. When studying for a test, you have an idea of which material you're most unsure of and devote more time to it.

Psychologists studying human metacognition usually rely on self-reports. Their subjects are able to simply tell the experimenter what they think. Studying metacognition in non-human animals is not as straightforward. How do you get an animal to "tell" you that it doesn't know something? Instead of verbal reports, scientists interpret behavioral indicators of metacognition in animals.

One such behavioral indicator is information seeking: If an animal doesn't know the correct response, will it take appropriate action to seek out the information that it needs?

In studies with rhesus monkeys, apes, and two-year-old children, experimenters placed several opaque tubes horizontally in front of the subjects. Their job was to choose the one tube that contained a piece of food. When the experimenter placed the food into one of the tubes in full view of the subjects, they all chose the correct tube. But on some trials, a barrier was placed in front of the tubes so they couldn't see which tube the experimenter loaded with food. On these trials, children, apes, and rhesus monkeys bent down to look through the tubes until they found the one with food and then chose it. This seems to indicate that they knew they were uninformed about the correct choice and thus took appropriate action to gather the information they needed.

A-Maze-ing Rats

Most of the evidence for metacognition in animals comes from studies with primates. Experiments looking for metacognition in rats have had mixed results. So Chelsea Kirk, Neil McMillan, and William Roberts of Western University Canada decided to see if rats would seek information when they didn't know the correct response to a task.

In their first experiment, Roberts and his colleagues trained rats to press a lever at the central point in a T-maze. The lever delivered a food reward, but it also lit up one of the two alleys, indicating where the rats could go to obtain another piece of food. Once the rats had learned to press the lever and enter the lit alley, the researchers stopped rewarding them for the lever press. They wanted to see if the rats would continue to press the lever in order to gain information about the location of food.

Without the immediate reward for lever pressing, the rats didn't press the lever as much, but they didn't stop completely: they pressed the lever on a little under half the test trials (two control groups, meanwhile, decreased their lever pressing to near zero).

Roberts and his colleagues wondered why the rats didn't press the lever every time to obtain the correct information they needed to find the food. They thought it might be related to the amount of information they obtained. The rats had only two choices, and pressing the lever narrowed it down to one choice. Even without pressing the lever, they had a 50/50 chance of choosing the correct arm randomly. Perhaps they would seek information more frequently if the amount of information they received for a response was greater.

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So in their next experiment, Roberts and his colleagues put rats in an 8-arm radial maze. Again, they trained the rats to press a lever in the center of the maze for a reward and to light up one of the eight arms where another piece of food was hidden.

This time, after the immediate reward for lever pressing ended, the rats continued to press the lever at high rates.

Roberts says the finding that the rats pressed the lever almost twice as frequently on the radial maze as on the T maze suggests that the rats' likelihood of information seeking was directly related to the amount of information gained.

"While a lever press in Experiment 1 reduced the probability of getting a reward from chance (0.5) to certainty (1.0 if the lit arm was chosen), a lever press in Experiment 2 reduced the probability of getting a reward from 0.125 (1/8) to 1.0," Roberts says.

Efficient Information Seekers

The researchers performed one more test to probe the rats' tendency to seek information when they needed it. In a final phase of Experiment 2, the researchers made the information provided by the lever press unnecessary. Instead of a randomly chosen arm containing food, the food was always located in the same arm. Thus, the rats could form a memory for the location of the food. Although lever pressing still illuminated the correct arm, the rats no longer needed this hint to know which arm to enter to get the food. In this phase, rats eventually stopped pressing the lever as they learned the location of the food. This result shows the rats were using the lever to obtain information when they needed it and ceased seeking that information when it didn't tell them anything they didn't already know.

Metacognition in animals can be controversial because it seems to suggest a level of self-awareness or self-reflective consciousness. While this may be the case, metacognitive abilities could also be present without consciousness. Roberts and his colleagues suggest that information seeking may be a relatively primitive process found in many species without necessitating reflective consciousness.

"Monitoring the environment for information probably emerged by natural selection for survival in many species," Roberts says. "Our findings may be just a product of this tendency."

Reference:

Kirk, C. R., McMillan, N. and Roberts, W. A. (2014). Rats respond for information: metacognition in a rodent? Journal of Experimental Psychology: Animal Learning and Cognition 40(2): 249-259. doi: 10.1037/xan0000018.