Nowadays, people text one another even if they are all in the same room. In 2010, we sent a total of 6.1 trillion text messages. Teenagers were responsible for a vast majority of these messages, with 63% texting on a daily basis. The average boy texts a median of 50 messages, while the average girl texts a median of 100 messages a day.
Our thumb twiddling earns the telecommunication industry $114.6 billion per year. Dopamine, a simple organic compound responsible for reward-driven learning in the brain system, may be fueling this constant need to send and receive texts. Every type of reward that has been studied increases the level of dopamine in the brain, and gives us that feel-good rush.
The smart phones beep is thought to be the reward for an incoming message. The incoming message itself can also be considered a reward for a message that you may have sent previously or for the time you had to spend waiting for the incoming message.