It is hard to pinpoint exactly when habits began to be studied because they are involved in so many different behaviors, such that they are now studied in a variety of fields. Psychology and behavioral science are fields deeply concerned with identifying and explaining the way that humans behave, which means that habits are of utmost interest to both.
All the way back in 1887, William James, a philosopher, and a psychologist, wrote a treatise titled Habits, in which he suggested that behavioral patterns shape who we are, in terms of our character and personality. The treatise demonstrated that habits have a very significant impact on our lives and our decision-making. He writes in Habits, “any sequence of mental action which has been frequently repeated tends to perpetuate itself.” 11
One of the earliest famous studies on habit-formation was conducted by psychologist Ian Pavlov. Ian Pavlov was actually studying digestion, which he later won a Nobel prize for in 1904. During some of his studies, he discovered an interesting psychological phenomenon, referred to today as Pavlovian theory.7
In his experiments, Pavlov was trying to measure how much saliva dogs produced when they digested.7 His lab assistant would therefore present his dogs with a bowl of food that would then lead to the dogs salivating, an unconditioned response. After a while, Pavlov found that the dogs would salivate when they saw his lab assistant. They had come to associate the assistant with food, thereby causing the response. Based on this observation, Pavlov wanted to see if he could create a conditioned response. Pavlov decided to test whether a stimulus associated with food would be enough to create the salivation response.8
To begin, Pavlov would ring a bell when he gave the dogs food. After this was repeated a few times, Pavlov tried ringing the bell without giving the dogs food. Pavlov found that the dogs still salivated, suggesting they had come to associate the stimulus of the sound of a bell ringing with receiving food; a habit had been formed.8 This habit-forming process later became known as classical conditioning. Classical conditioning prompted the field of behaviorism because it suggests that individuals can be trained to perform an action through habit.
American psychologist B.F Skinner was the first to study operant conditioning. In 1948, Skinner examined how rats’ behavior changed based on different reinforcements. For positive reinforcement, he put hungry rats into a box that had a lever that would dispel food when pushed.9 The rats figured out that they would be rewarded for pressing a lever, and therefore after a while, the rats would go press the level immediately when they were put in the box. To show how negative reinforcement could also form habitual behavior, Skinner would place rats in a box with a level that would give them a small electric shock until they pressed a level that would turn off the electric current. After a while, the rats would go press the level immediately when they were put in the box.9 Skinner’s experiments demonstrated that habits could be formed through operant conditioning, which is a form of reinforcement learning.
Habits are also often studied in relation to health and fitness. Many people want to lose weight or get fitter, but in order to do so, we often have to break old habits and create new, healthier ones. Bad habits, like eating cookies because they make you feel good, are hard to break. Various studies have demonstrated that eating behavior is shaped by habits. There is a study by David Neal and Wendy Wool from 2011 that showed that people had formed a habit of eating popcorn while at the movie theatre and were thus likely to continue even if the popcorn they were served was stale.10
Another recent influential figure on habitual behavior is American author Gretchen Rubin. She has dedicated herself to researching habits and happiness. She has written various books and delivered numerous talks that discuss how habits are formed and strategies for creating better ones. To hear more about her work with habits, check out this podcast.