Discussion: Learning

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There are two types of learning: associative learning and non-associative learning. Associative learning is when you learn something new about a new kind of stimulus (that is, an extra stimulus). Non-associative learning is when you're not pairing a stimulus with a behavior. Non-associative learning can be either habituation or sensitization.

Habituation is when repeated exposure to a stimulus decreases an organism's responsiveness to the stimulus. What are some things in life that we experience over and over again and react less and less to? What's an example of habituation in real life?

Sample Answer

Noise is a great example of something that we habituate to. Say you go to the library to do some studying, but they're doing construction and you didn't know about it. The first time you hear construction noise—bam!—it's a little scary; the second time you hear it it's a little less scary; the third and fourth and fifth time…and after hours and hours of studying for your Introduction to Psychology exam in the library, you barely even notice this noise at all.

Do people live in dormitories on campus? And do people burn popcorn in these dorms, does this happen? And what happens when you burn popcorn? The fire alarm goes off. What happens the very first time the fire alarm goes off when you're in college? You panic! Oh my goodness, I'm in college, I brought everything I own and put it in this tiny little space and now it's going to burn up and be gone. Everyone runs outside in their PJs. Well, the second time the fire alarm goes off, we move a little slower, because last time it was just burnt popcorn. The third time, we move a little slower, the fourth time we move a little slower. The fifth time, we don't even get out of bed. That's habituation in real life.


Sensitization is kind of the opposite. It's learning that occurs when stimulus is repeated, and each time your response to it increases as it goes on and on. So what's an example of sensitization in real life?

Sample Answer

Anyone have siblings? You're in the car with your sister and she pokes you in the shoulder and you're like, "Quit it." She pokes you in the shoulder and you're like, "Quit it!" She pokes you in the shoulder and you're like, "QUIT IT!" She pokes you in the shoulder and you punch her in the face. That's sensitization: you're increasing your behavioral response as the stimulus is repeated.


Habituation is an excellent way to investigate learning in those who can't report what they're learning, like animals or babies, because as you present a stimulus over and over again, the organism cares less and less about it. You can measure this through looking time—a method used when studying babies. Habituation is also a great way to find out whether an organism can tell the difference between two kinds of stimuli. When studying an animal, if a stimulus is played over and over and over again and the animal gets very bored with it, looking time will decrease. When faced with a new, or novel, stimulus (and the animal can tell that it's new), looking time will increase. But if it can't tell the difference, it will remain habituated.

Classical conditioning is a type of associative learning that occurs when a neutral stimulus becomes paired with a stimulus that causes a behavior. After a while, the neutral stimulus can produce the behavior all by itself. Psychologists have come up with all kinds of complicated names for these things, and it will be worth knowing what they are and how they apply to different examples.

In the case of Pavlov's dog, food is the unconditioned stimulus. Unconditioned stimulus is natural. No learning had to be involved. What is the unconditioned response? It's the drooling, the dog's natural response. The neutral stimulus is what the dog just does not care about; it has no particular response to this sound. But if you do this repeated pairing, playing the neutral stimulus and presenting the unconditioned stimulus, what will happen eventually? The dog will salivate in response to the sound. This makes the sound the conditioned stimulus.

Remember that the unconditioned response and the conditioned response are essentially the same thing: getting excited about the food. It's just how they're brought about that's different.

So we can think about the temporal order that these occur in. We can think about forward conditioning, in which the conditioned stimulus occurs before the unconditioned stimulus (bell and then food); backward pairing, in which the unconditioned stimulus comes first (food and then bell); or simultaneous conditioning, when they occur together. And what do you think is the most effective way to train somebody up on this? Which of these will help you learn the bell and the food best of all?

Sample Answer

Forward conditioning: when you have the conditioned stimulus before the unconditioned stimulus, it gives the animal time to figure out that the bell means something, so that they can form an association and have it proven correct. Classical conditioning is all about prediction. When you get the food first, other stuff may happen at the same time, or a little later, but it's not that important to you.


A second type of associative learning is operant, or instrumental, conditioning. This is the process by which a behavior becomes associated with its consequences. The big difference is that there isn't an unconditioned stimulus initially. The animal does something, something positive happens, and so the behavior is repeated. And this comes about by the law of effect: actions that lead to a more satisfying state of affairs are more likely to be repeated.

Operant conditioning can be brought about by a variety of reinforcement schedules and reward types. We can think of reinforcement as a reward—what you do to promote good behavior—and punishment as, well, punishment—what you do to punish bad behavior. And we're going to get into some terms that are a little bit counterintuitive, so let's think about why they're called what they are.

You can have positive reinforcement, which is where something good is given. Reinforcement because it's a reward, and positive because something is introduced.

Positive punishment is when something bad is introduced in order to shape behavior in the opposite direction, and negative punishment is when something good is taken away.

As you grapple with these somewhat confusing terms, try to add your own examples to the chart:

  • If you do good science, you win a Nobel Prize
  • If a child is naughty, he gets a spanking
  • If you pass the first quiz, you don't have to take the second quiz
  • If you commit a crime, you lose your freedom


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