Big-city brains

Why are people in big cities better than those in small towns? (I can sense some people exiting this page.)

The answer may be rooted in the neurochemistry and neuroanatomy of our brains. Scientists demonstrated that our brains can be altered by either formal training or informal experience.

Let's consider this experiment. Rats of the same sex were randomly assigned to three environments: standard condition (SC), impoverished condition (IC), and enriched condition (EC). In the SC, three animals were kept in a typical-sized cage and given food and water. This was the control group. In the IC, only one rat was kept in an SC-sized cage. In the EC, 10 to 12 animals entered a large cage containing ladders, treadmills, a sort of obstacle course, and the like. These stimuli were changed daily. This environment is considered enriched because it provides more informal learning than does the SC.

So what happened? The answer has to do a lot with the cerebral cortex, one of the most important parts of the brain and that which is responsible for complex cognition. Total enzymatic activity and the physical weight of this area increased in the rats put in the EC. This result was not influenced by greater handling of the rodents in the EC situation (this experiment has been done on several other animals as well).

Experience in an EC environment induces better learning and problem-solving abilities. This type of environment alters the expression of a plethora of genes, some of which play key roles in learning and memory. ECs also aid recovery from conditions such as malnutrition and brain damage. It has been shown that, for recovery in brain injury in animals, enriched environments prove more effective than formal training or physical exercise. The amount of dendritic branching and the size of synaptic contacts also shot up in the animals kept in the EC.

And what does all this mean? It suggests that animals and people in more crowded areas with more activities tend to process information faster and more efficiently than those in smaller or mid-sized towns, as also in the case of memory storage. Which explains why city dwellers are just better and smarter than you. I live in a suburb, by the way.

Paraphrased from Biological Psychology, chapter 18.