Impact of income inequality on the brain

Income inequality is an undeniable reality in India and in most other parts of the world. The effects of poverty on health, education and other dimensions have been well documented. Recent research studies seek to understand how income levels may be correlated with differences in the structure of the human brain. The brain’s primary function is to enable cognition—the action or process of acquiring knowledge and understanding through thought, experience and the senses. Unlike all other organs, which look and behave more or less the same from birth to death, the brain evolves constantly over a person’s lifespan. This happens as a response to the brain’s external environment— which is the totality of all stimuli which have historically been transmitted to the brain via all of the human senses. In other words, everything you ever saw, heard, smelt, tasted or touched has shaped your brain. Unlike in a computer, where hardware and software are two disparate aspects, in the brain, form and function are deeply interwoven.

Learning results in a change in the connectivity and structure of the brain, and therefore the type of activity it is able to produce, and the subsequent nature of learning it is capable of. It is an intricate feedback loop. The physical structure of the brain and its processing capacity are two sides of the same coin. To use an economics analogy, one cannot describe the GDP potential of a country independent of the infrastructure it has created. It is only once the requisite infrastructure is built that achieving a higher level of economic output becomes possible. And the output, in turn, may be re-invested to modify the infrastructure in big and small ways to enable even greater GDP. Science has shown us that the structure of the brain is shaped by the complexity of the stimulus environment one encounters. Studies done on rodents, for example, show that placing the animal in a more complex or enriched environment with greater stimuli has far reaching impact on gene expression in the brain, the growth of new neurons and the number of connections between them, and how synapses “learn”.