What is the term for the initial learning of the stimulus response link?

In the learning process known as classical conditioning, the unconditioned stimulus (UCS) is one that unconditionally, naturally, and automatically triggers a response. In other words, the response takes place without any prior learning.

Contrast this with the condition stimulus. It only prompts a response after a person or animal has learned to associate the stimulus with a certain response.

Unconditioned stimuli are all around us. Think about:

• The smell of a favorite food, which immediately makes you feel hungry
• A feather tickling your nose, which causes you to sneeze
• An onion's smell as you cut it, which makes your eyes water
• Pollen from grass and flowers, which causes you to sneeze
• A unexpected loud bang, which causes you to flinch

In each of these examples, the unconditioned stimulus naturally triggers an unconditioned response or reflex. You don't have to learn to respond to the unconditioned stimulus; it occurs automatically.

In Ivan Pavlov's classic experiment with dogs, Pavlov and his assistants showed the dogs edible and non-edible items and measured saliva production with each. Salivation occurred automatically and without the dogs' conscious effort when they smelled the food.

This response required no learning. The food was an unconditioned stimulus because it prompted a reflexive response.

Building on Pavlov's work, behaviorist John B. Watson and graduate student Rosalie Rayner conducted what came to be known as "the Little Albert experiment." The research showed that emotional reactions could be classically conditioned in people.

Watson and Rayner exposed a 9-month-old child, Albert, to a white rat, a rabbit, a monkey, masks, and burning newspapers and observed the boy's reactions. He showed no fear of them at first.

But after Watson began making a loud noise—an unconditioned stimulus that provoked Albert's crying—whenever he showed Albert the white rat, Albert became frightened whenever he saw the white rat. Because he'd learned to associate the white rat with a noise he feared, he ultimately reacted with fear to the rat as well. The rat, once a neutral stimulus, had become a conditioned stimulus.

For the purposes of classical conditioning or learning, you need a neutral stimulus as well as an unconditioned stimulus. In other words, for conditioning to take place, you must first start by pairing a neutral stimulus with an unconditioned stimulus.

A neutral stimulus doesn't trigger any particular response at first, but when used together with an unconditioned stimulus, it can effectively stimulate learning, eventually becoming a conditioned stimulus. A good example of a neutral stimulus is a sound or a song.

When it is initially presented, the neutral stimulus has no effect on behavior. As it is repeatedly paired with an unconditioned stimulus, it will begin to cause the same response as the UCS.

For example, the assistants in Pavlov's experiment initially elicited no salivation and therefore were neutral stimuli. Likewise, the sound of a squeaky door opening is initially a neutral stimulus. If that sound is repeatedly paired with an unconditioned stimulus, such as feeding your cat, that sound will eventually come to trigger a change in your cat's behavior. Once an association has been formed, your cat may react as if it is being fed every time it hears the squeaky door open.

An unconditioned stimulus causes a response without any prior learning on the part of the subject. The response is automatic and occurs without thought. In contrast, a conditioned stimulus produces a reaction only after the subject has learned to associate it with a given outcome.

In Pavlov's experiments, the dogs learned to salivate when they saw the assistants' white lab coats because they'd formed an association between the assistants and the food they presented, The salivary response to the assistants was not an automatic, physiological process, but a learned one. The presence of the assistants, initially a neutral stimulus, became a conditioned stimulus.

Throughout the classical conditioning process, a number of factors can influence how quickly associations are learned. The length of time that passes between presenting the initially neutral stimulus and the unconditioned stimulus is one of the most important factors in whether learning occurs.

The timing of how the neutral stimulus and the unconditioned stimulus are presented is what influences whether or not an association will be formed, a principle that is known as the theory of contiguity.

In Pavlov's experiment, the sound of a buzzer was initially a neutral stimulus, while the smell of food was an unconditioned stimulus. Presenting the tone close to presenting the smell of food resulted in a stronger association. Ringing the buzzer, the neutral stimulus, long before the unconditioned stimulus led to a much weaker or even nonexistent association.

Different types of conditioning may use different timing or order between the neutral stimulus and the UCS.

• In simultaneous conditioning, the neutral stimulus is presented at the exact time as the unconditioned stimulus. This type of conditioning leads to weak learning.
• In backward conditioning, the unconditioned stimulus is given first, and the neutral stimulus is presented afterward. This type of conditioning also tends to result in weak learning.
• In trace conditioning, the neutral stimulus is presented briefly and then stopped, then the unconditioned stimulus is presented. This type of conditioning produces good results.
• In delayed conditioning, the neutral stimulus is presented and continues while the unconditioned stimulus is offered. This type of conditioning produces the best results.

Three Major Types of Learning

1)      Learning through association  - Classical Conditioning

2)      Learning through consequences – Operant Conditioning

3)      Learning through observation – Modeling/Observational Learning

LEARNING

Learning is a change in behavior or in potential behavior that occurs as a result of experience.  Learning occurs most rapidly on a schedule of continuous reinforcement.  However it is fairly easy to extinguish… switching to variable reinforcement after the desired behavior has been reached prevents extinction.

CLASSICAL CONDITIONING

If a neutral stimulus (a stimulus that at first elicits no response) is paired with a stimulus that already evokes a reflex response, then eventually the new stimulus will by itself evoke a similar response.  (UCS, UCR, CS, CR)

·        Each pairing of the CS with the UCS strengthens the connection between the CS and CR.

·        Timing is important.  Usually the strongest and fastest conditioning occurs when the CS is presented about ½ to one second before the UC.

·        EXTINCTION - If the CS is presented repeatedly in the absence of the UCS, the CS-CR bond will weaken and the CR will eventually disappear.

·        STIMULUS GENERALIZATION - Once conditioning has occurred the subject may respond not only to the CS, but to stimuli similar to it.  For example, many of our likes and dislikes of new people and situations come from generalization based on similarities to past experiences.

·        STIMULUS DISCRIMINATION – opposite of stimulus generalization.  SD is the ability to detect differences among stimuli.  This procedure is sometimes used to test the ability of nonverbal subjects to discriminate among various stimuli, such as color (air puff / eye blink).

OPERANT CONDITIONING

The organism operates on its environment in some way; the behavior in which it engages are instrumental to achieving some outcome.

LAW of EFFECT

If a response is followed by a pleasant or satisfying consequence, that response will be strengthened.  If a response is followed by an unpleasant or negative state of affairs, it will be weakened.

Differences Between Operant and Classical Conditioning

1)      In classical conditioning, the conditional behavior (CR) is triggered by the particular stimulus (CS) and is therefore called an elicited behavior.  Operant behavior is an emitted behavior in the sense that it occurs in a situation containing many stimuli and seems to be initiated by the organism.  In a sense the subject chooses when and how to respond.

2)      In classical conditioning, behavior (CR) is affected by something that occurs before the behavior (the CS-UCS pairing).  In contrast, the operant response is affected by what happens after the behavior – that is by its consequences.

Positive Reinforcement

Any stimulus or event that increases the likelihood of the occurrence of a behavior that it follows.

Shaping

Shaping is the method of successive approximations.  Shaping reinforces the behaviors as they get closer and closer to the desired behavior.

Negative Reinforcement

Negative Reinforcement is anything that increases a behavior that results in the reinforcers removal.

Punishment

Any consequence that decreases the future occurrence of a behavior that produces it.

When You Remove a Positive Stimulus

Extinction       If the stimulus is a reinforcer for the behavior (e.g., parent ignores child/withdraws attention when child  acts up to get attention)

    Response Cost

       OPERANT CONDITIONING CONSEQUENCES