Dopamine & the Skinner Box Experiment

How Rewards Shape What We Do?

We all know that dopamine is also known as "feel-good hormone" as it works on our brains' reward system. But how exactly does it shape our behavior—whether you’re a human, a dog, or a rat in a lab?

Dopamine levels in our brains increase by performing pleasurable activities, encouraging the behavior and we tend to repeat it in the future. Let’s dive into how dopamine, reward, and learning are connected, with a little help from one of psychology’s most famous experiments: B.F. Skinner’s Skinner Box.

Who was B.F. Skinner?

B. F. Skinner was an American psychologist, researcher, philosopher, inventor, and author. He is best known for his scientific approach to studying human behavior and his contributions to behaviorism [1]. Skinner believed that we both predict and control our behavior. Thus, by manipulating our environment, we can manipulate our behavior. [2]

He invented a number of devices for his experiments, the most popular of which was the “Skinner box experiment”.

What did he do?

Skinner Box experiment

The "Skinner box" is a setup used in animal experiments. It is also known as an “operant conditioning chamber”.

Skinner believed "all human behavior is acquired via conditioning and that our choices are influenced by the environment, not entirely free" i.e. behavior could be both predicted and controlled by changing environmental conditions [2]. 

The core concept behind the experiment was to test the theory of operant conditioning, a type of learning where the consequences of a behavior determine whether that behavior will be repeated in the future.

Setup

In this experiment, a rat was placed in the Skinner box with a lever. The rat receives a shock for pressing the lever when a red light is on but receives food for performing the same behavior when a green light is on.

What happened?

At first, the rat’s behavior is quite random as it explores its new environment. As the rat started to explore the box, it would stumble upon the lever and get food. It quickly learned that pressing the lever when light was green resulted in a positive outcome (food or water), thus increasing the frequency of that behavior. On the other hand, when the rats pressed the lever when light was red, it resulted in a negative outcome (electric shock), thus decreasing the behavior.

The rat learns to distinguish between an experience that signals a reward (green light) and the one that does not (red light). [1]

Here, if a rat receives a shock for pressing a lever when a red light is on but receives food for performing the same behavior when a green light is on, it will quickly learn to press the lever only in the presence of a green light [1].

Operant Conditioning

Operant conditioning is a learning process in which an individual's behavior (its likelihood of being repeated in the future) is influenced through rewards or punishments the individual gets based on the consequences of the behavior. This concept was first introduced by B. F. Skinner in the mid-20th century.

In operant conditioning, the organism actively operates on the environment, producing a consequence. Also, the organism learns to distinguish between stimuli that signal a reward and those that do not. [1]

The Principles of Operant Conditioning:

• Positive reinforcement - a rewarding experience is presented following the behavior (e.g. a child gets a lollipop for tidying up his room)
• Negative reinforcement - an unpleasant experience is removed following the behavior (e.g. the annoying beeping sound stops when you buckle your seatbelt)
• Positive punishment - an unpleasant experience is added as a consequence of the behavior (e.g. getting a failing grade for copying during a test)
• Negative punishment - a rewarding experience is removed as a consequence of the behavior (e.g. Nora stays out past curfew, so her dad takes her cell phone away)

In the Skinner Box, the food acts as a reinforcer, causing the rat to deliberately press the lever more frequently when the light is green [1] and the electric shock acts as a punishment for the rat which causes the rat to avoid pressing the lever when the light is red.

This also happens in our day-to-day lives. Once we experience a reward or punishment, we are likely to perform (or not perform) that behavior again in anticipation of the result [1]. For example:

• Hot Stove: If you put your hand on a hot stove, you will get burned. More importantly, you are very unlikely to put your hand on that hot stove again. Even though no one has made that stove hot as a punishment, the process still works.
• Superstitions: Many superstitions result from accidental reinforcement. A gambler who happens to blow on his dice just before a big win will likely keep engaging in that behavior even though his success has absolutely nothing to do with the act of blowing on the dice. This is because the behavior of blowing on his dice has been reinforced.

Applications of Operant Conditioning in daily lives:

The principles of operant conditioning have been used in various ways outside of the laboratory.

• Training pets often involves rewarding desired behaviors to reinforce them. In one such case, if you wish to train your dog to roll over on command, you could reward the dog each time it spontaneously performs this behavior. Repeated reinforcement would eventually lead the dog to learn and repeat the behavior.
• Parents have used rewards to encourage positive behaviors in their children, such as offering kids a treat for finishing their chores or staying on task during remote learning.
• Apps like fitness trackers or habit-building tools use rewards (points, badges) to encourage behaviors like exercising or drinking water.
• Tools like Duolingo use rewards (streaks, achievements) to motivate consistent learning.
• Operant conditioning principles are used in therapies to modify behaviors, especially in individuals with autism or other developmental disorders.

   Where Does Dopamine Come In?

It was observed that when the rats received food or water as a reward, their brains released dopamine. This process illustrates the 'reward system' of our brain.
Behavior which has reward will likely be repeated and behavior with punishment will likely not be repeated. Hence, rewards and punishments were crucial to shape and encourage voluntary behavior.

While Skinner did not study brain chemistry, later neuroscience research has shown that behaviors reinforced with rewards (like food) trigger dopamine release. This helps explain why rewards are so effective in shaping behavior.

Criticisms:

While the Skinner box experiment provided valuable insights, it has been met with criticism:

1. Skinner's experiments involve single animals and controlled environment discrepancies about human behavior cannot be made on the basis of these studies since humans are much more complex.
2. Contrary to what Skinner believed, studies have shown that reinforcement and punishment are not necessary for learning to take place. Behaviors can also be learned through observation (Bandura's experiments) and insight. [1]
3. Because the environment in a Skinner box is so controlled, it may not accurately reflect how an animal would behave in an environment outside the lab. [3]
4. Operant conditioning certainly becomes more complicated when it comes to human reinforcements (such as free will, individual preferences).
5. Also, Skinner box can be quite stressful for the animals involved. The design of the Skinner box is intended to keep an animal from experiencing other stimuli, which can lead to stress and anxiety. [3]

The criticisms of Skinner's work led to the development of cognitive-behavioral approaches that emphasize mental processes alongside observable behavior.

Operant conditioning, demonstrated by Skinner's experiments, provides a valuable framework for understanding how behavior is influenced by its consequences. While it may not capture the entire human reinforcements, its principles remain relevant in both everyday life and various professional fields. Understanding and applying these principles can help us shape behaviors, predict outcomes, and appreciate the complexities of learning and adaptation.

[1] Skinner’s Box Experiment (Behaviorism Study) - Practical Psychology

[2] Operant Conditioning - The Skinner box experiment

[3] Skinner Box: What Is an Operant Conditioning Chamber?