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Classical conditioning: Neutral, conditioned, and unconditioned stimuli and responses

Video transcript

so I have a pet guinea pig and here she is and one thing that guinea pigs love like all pets do is when they get a treat now my guinea pig happens to love carrots and whenever I give her a carrot she acts very excited it's actually really cute to see her so excited and it makes me kind of jealous because I wish I could get so excited about a raw vegetable so imagine how much healthier I would be but for her that excitement comes naturally I never had a trained her to enjoy carrots when she was first living in my apartment I used to like to surprise her by getting a carrot out of the refrigerator and bringing it over to her cage now the thing you need to know about my refrigerator is that the door is always stuck so I have to pull pretty hard to get it open and when I do that makes a loud popping sound so after a few weeks and my guinea pig living in my apartment I discovered that I couldn't surprise her any more with a carrot because as soon as she heard the sound of the refrigerator door being pried open she was already acting excited even before I gave her a carrot I also noticed that when I would open the refrigerator to make a snack for myself she would respond to the sound of the door by acting excited even if she wasn't going to get a carrot this learned response that she developed to the sound of a refrigerator door is referred to in psychology as classical conditioning whether you realize it or not classical conditioning is a topic that you're already very familiar with the concept of classical conditioning is easy to understand the challenge is understanding and applying the correct terminology so let's talk about that terminology so I'm going to write s for stimulus and the stimulus is anything that stimulates your senses it's anything you can hear see smell taste or touch and stimuli can produce a response which I'll write as an R so stimulus produces a response so let's use this example to make the terms clear no one had teach my guinea pig to act excited about carrots it's our normal physiologic response and since no one had a teacher that about carrots we can refer to the carrot as an unconditioned stimulus which I'll write as UCS an unconditioned stimulus triggers some kind of logic response so in our case the carrot triggers excitement the excitement is the response in fact the more descriptive way to refer to this response is to call it an unconditioned response so an unconditioned stimulus elicits an unconditioned response so you might be asking yourself why complicate things by sticking the term unconditioned in front of it well as we're about to see there are different types of stimuli and responses so for now think of the word unconditioned as something you already do naturally and if something happens naturally then it really wasn't learned it's an innate process conditioned on the other hand means something is learned and remember classical conditioning is a type of learning so you can remember conditioning means to learn if you've ever heard someone use the phrase I'm conditioning myself to like it said differently I'm learning to like it so unconditioned means it happens naturally conditioned means it was learned I think of what was happening right before she got her carrot my refrigerator door opened which made a loud popping sound so we can refer to the sound of the door as a neutral stimulus a neutral stimulus is something you can sense by either seeing it chasing it or in our case hearing it but it doesn't produce the reflex being tested so in our case the refrigerator door can be heard but the sound of the door doesn't naturally calls excitement that's something that had to be learned which is why she didn't respond the first few times she heard it so since the refrigerator door doesn't cause excitement on its own we say the refrigerator door is a neutral stimulus has immediately followed by the unconditioned stimulus of the carrot which causes the unconditioned response of excitement now classical conditioning is established when the neutral stimulus is presented followed a short time later by the unconditioned stimulus and the presentation of both stimuli is called a trial so pairing these two stimuli together is how you establish classical conditioning but see my case I didn't know I was establishing classical conditioning but I really was I was pairing the sound of the refrigerator door being opened with the presentation of a carrot in classical conditioning actually occurs when the neutral stimulus in our cases sound of the refrigerator door is able to elicit the same response as the unconditioned stimulus the carrot so in our example we can say classical conditioning had taken place when the sound of the refrigerator door alone was enough to cause excitement even if she didn't receive the carrot and when this has happened we say the neutral stimulus is no longer neutral announced the conditioned stimulus because it's acquire the ability to elicit a response that was previously elicited by the unconditioned stimulus the carrot so there's that word again conditioned in conditioned stimulus which as I said earlier means learned my guinea pig was conditioned to respond to the sound of the refrigerator by behaving excited in the excited response that's now associated with the refrigerator door is no longer the unconditioned response because in this context she had to learn to respond with excitement to the sound of the door so the proper term for this response is a called a conditioned response because it is a learned response so that's the idea behind classical conditioning because of it I now feel obligated to have to give my guinea pig a care at any time I open the refrigerator