Do Bigger Brains Mean Better Self Control?

According to a recent study, scientists believe that brain size may be attributed to better self control. A total of 36 species tested suggested that ecology and brain size play direct roles in cognitive evolution. MacLean and his colleagues conducted two tests for self control in species ranging from elephants to birds to primates. In the first test, researchers would repeatedly hide a piece of food in one area where the animal could see, until the animal was used to finding the food in that particular spot. The researchers then hid the food in a different place, still where the animal could see it. If the animal chose the new area to look for the food the researchers marked it as the animal having exercised self control. This is because they believed the animal had "the ability to inhibit a prepotent but ultimately counter-productive behavior." In the second test, researchers hid food in an opaque container with a hole in the back for the animals to reach the tasty treat. Once the animals had gotten used to this task, the opaque container was switched with a transparent one. If the animals reached in the hole for the food instead of trying to reach through the container they were believed to have self control. The researchers then compared the results of the tests to each animal's "absolute" brain size and with brain size relative to their body size. The great apes showed good self control along with the carnivores (dogs and wolves). Elephants showed poor self control yet only completed one of the tests. These results highlight interesting ecological and evolutionary differences between the species when they are compared to each other. Overall, species with larger brain sizes tended to do better than species with smaller brain sizes (absolute brain size). However, brain size was not linked to self control because the researchers did not have data on the degree of "folding" of each species' brain which is correlated with intelligence as well. The researchers also looked at the diets and social behaviors of each species tested and found that the richer the diet the better self control the species had in general, such as the great apes. Although they did not test humans, it would be interesting for them to do in the future, as well as expand their species repertoire.

References

MacLean, E 2014 'Animals with bigger brains have more self-control', LiveScience.