In the 1950s psychologist B. F. Skinner conducted experiments to understand how variability impacted animal behavior. First, Skinner placed pigeons inside a box rigged to deliver a food pellet to the birds every time they pressed a lever. Similar to Olds’s and Milner’s lab mice, the pigeons learned the cause-and-effect relationship between pressing the lever and receiving the food. In the next part of the experiment Skinner added variability. Instead of providing a pellet every time a pigeon tapped the lever, the machine discharged food after a random number of taps. Sometimes the lever dispensed food, other times not.
Skinner revealed that the intermittent reward dramatically increased the number of times the pigeons tapped the lever. Adding variability increased the frequency of the pigeons’ completing the intended action.
Skinner’s pigeons tell us a great deal about what helps drive our own behaviors. More recent experiments reveal that variability increases activity in the nucleus accumbens and spikes levels of the neurotransmitter dopamine, driving our hungry search for rewards. Researchers observed increased dopamine levels in the nucleus accumbens in experiments involving monetary rewards as well as in a study of heterosexual men viewing images of attractive women’s faces.
Variable rewards can be found in all sorts of products and experiences that hold our attention. They fuel our drive to check email, browse the web, or bargain-shop.
This tidbit is from the book Hooked by Nir Eyal