In the context of learning, what is a stimulus?
A stimulus is any event, object, or other phenomenon to which an individual can respond.
For example, a loud noise that causes a person to jump up in surprise is a stimulus.
Name the two types of learning, distinguished by whether they involve a single stimulus or an association between multiple stimuli/events.
Associative and non-associative learning
Associative learning involves an association between multiple events (such as food and a sound played by an experimenter). Non-associative learning involves only a single stimulus.
Name two types of non-associative learning.
The two main types of non-associative learning are habituation and sensitization.
Many new stockbrokers on the exchange floor have difficulty getting work done with the commotion going on around them. Over time, they become so accustomed to the sound that they don’t even notice it. This exemplifies which form of non-associative learning?
Habituation
Habituation is a decrease in response to a stimulus after repeated presentation of the stimulus. This is one of the simplest and most common forms of learning, since it allows us to tune out non-essential stimuli and focus on important things.
Responding to a old, previously habituated stimulus as if it were newly presented is termed:
dishabituation.
This situation occurs when a subject repeatedly experiences the same stimulus, gets used to it, and stops responding (habituation). Dishabituation can then take place if he or she is given a new stimulus and is then provided with the original stimulus again, at which point the subject responds to it like he or she did originally.
A type of non-associative learning that is sometimes thought of as the opposite of habituation is:
sensitization.
Sensitization occurs when repeated exposures to the same stimulus triggers an increase in sensitivity to that stimulus.
When rats in a study were given cocaine, they initially showed no response. However, if the same dose of cocaine was given a week later, the rats displayed increased head movement. This exemplifies:
sensitization.
Sensitization refers to the increased response to a stimulus upon repeated administrations. Note that the opposite—habituation, or the decreased response to a stimulus over time—can also occur with drugs and contributes to tolerance and dependency.
Name two types of associative learning.
The two main types of associative learning to understand for the MCAT are classical conditioning and operant conditioning.
Name the five components (stimuli and/or responses) of classical conditioning.
The five components of classical conditioning are:
- a neutral stimulus
- an unconditioned stimulus
- a conditioned stimulus
- an unconditioned response
- and a conditioned response.
In the context of classical conditioning, what term describes something that naturally elicits the response being studied?
In Pavlov’s dog experiment, this was the food originally presented to the dogs.
The unconditioned stimulus
An unconditioned stimulus (US) is a stimulus that elicits the desired response without any conditioning. In Pavlov’s experiment, showing the dogs food made them salivate.
In the context of classical conditioning, what term describes something that elicits the response being studied, but only after conditioning has occurred?
In Pavlov’s dog experiment, this was the sound that was produced immediately before the dogs received food.
The conditioned stimulus
A conditioned stimulus (CS) is a stimulus that elicits the desired response once conditioning has occurred. In Pavlov’s experiment, the sound came to be associated with the presentation of food, and it eventually provoked salivation (the response) in the dogs even when no food was presented.
By the way, throughout this deck, we’ll be using “sound,” rather than “bell,” in the context of Pavlov’s experiment. Long story short, Pavlov didn’t exactly use a bell in his experiments, but rather a variety of sounds, from a metronome to a buzzer. That knowledge isn’t MCAT-relevant, but we wanted to let you know here to avoid confusion.
In Pavlov’s dog experiment, playing the sound before conditioning occurred did not cause the dogs to salivate. At this point, the sound is termed a:
neutral stimulus.
There are a lot of stimuli (3!) in classical conditioning, so let’s make sure we have them down.
Neutral stimulus: A stimulus that naturally elicits no response.
Unconditioned stimulus: A stimulus that naturally elicits the desired response (example: the food).
Conditioned stimulus: A stimulus that was previously neutral but that elicits the desired response once conditioning occurs.
In Pavlov’s dog experiment, when the dogs salivated in response to the presentation of food, salivation was a(n):
unconditioned response.
In classical conditioning, an unconditioned response is a response that occurs naturally upon the presentation of an unconditioned stimulus (which, in Pavlov’s study, was food).
In classical conditioning, once conditioning occurs, the action that was previously termed the unconditioned response is known as the _____________.
conditioned response
This might seem like an easy question! However, it’s very important to understand what is going on here. Let’s use the classic example of Pavlov’s dogs. Before the dogs were conditioned, the presentation of food (the unconditioned stimulus, or US) provoked salivation (the unconditioned response, or UR). Once the dogs were conditioned to associate a sound with food, salivation began to occur in response to that sound (the conditioned stimulus, or CS). That salivation is termed the conditioned response, or CR.
In summary, a response that occurs due to the US is a UR. A response that occurs due to the CS—even though it’s the same response—is a CR.
In classical conditioning, the neutral stimulus later becomes:
a conditioned stimulus.
The goal of classical conditioning is to turn a previously-neutral stimulus into a conditioned stimulus that elicits the desired response through pairing with an unconditioned stimulus.
This is the portion of conditioning that occurred while Pavlov’s dogs were learning to salivate in response to a sound.
Acquisition
Acquisition takes place when the subject is learning the association. The dogs initially learned to salivate because Pavlov gave them food immediately after playing the sound.
If Pavlov ran out of food to present to the dogs while playing the sound, _______ could occur and the association would be lost.
If Pavlov ran out of food to present to the dogs while playing the sound, extinction could occur and the association would be lost.
Extinction occurs when the conditioned stimulus is no longer paired with the unconditioned stimulus for an extended period of time. This causes the association to be lost and the conditioned behavior to stop.
After loss of association in Pavlov’s experiments due to Pavlov ceasing to present food, the dogs may experience _________ if Pavlov stops playing the sound for a few days and the association returns briefly once he resumes playing it.
spontaneous recovery
This is when the association returns after extinction, typically after a break in the presentation of the conditioned stimulus. This recovery is transient, and the response is often not as strong as before.
True or false:
For spontaneous recovery to take place in the context of classical conditioning, extinction must first have occurred.
True
This statement is accurate. By definition, spontaneous recovery is the recovery of a learned response that takes place after extinction.
Define:
stimulus discrimination
Stimulus discrimination refers to the ability of a subject to differentiate relevant stimuli from similar but irrelevant stimuli.
The subject will then respond to the relevant stimuli but will ignore the irrelevant ones.
Define:
stimulus generalization
Stimulus generalization refers to the tendency for a subject to begin responding to stimuli that are similar, but not identical, to the stimulus of interest.
This is essentially the reverse of stimulus discrimination.
The Little Albert study, in which a boy was initially made to be afraid of a white rat but later exhibited fear in response to a variety of stimuli resembling white fur, exemplifies:
stimulus generalization.
Since this example involves the broadening of stimuli to which the subject responds, it constitutes stimulus generalization.
If my cat learns that the high-pitched sound of one drawer opening means that she is about to be fed, but she ignores the sound of a different drawer opening, this exemplifies:
stimulus discrimination.
Since my cat can distinguish, or discriminate, the relevant stimulus from other, similar stimuli, this situation constitutes stimulus discrimination.
Which type of conditioning is focused on increasing or decreasing the frequency of a voluntary behavior?
Operant conditioning
Operant conditioning involves changing the frequency of a voluntary behavior by administering either reinforcement or punishment.
Famous for his theory of behaviorism, which scientist is most strongly associated with operant conditioning?
B.F. Skinner
Skinner created the “Skinner box,” an operant conditioning chamber used with rats or pigeons.
While the MCAT doesn’t often ask questions about the names of psychologists (preferring instead to ask about their theories), B.F. Skinner is a potential exception due to his wide-reaching influence.
True or false:
For operant conditioning to be effective, every instance of the behavior must be either rewarded or punished.
False
This statement is untrue! In fact, the entire concept of reinforcement schedules is oriented around the idea that operant conditioning works even if only some instances of behavior are rewarded/punished.
A reinforcement schedule in which every good behavior or correct response is reinforced is termed:
continuous reinforcement.
As one might expect, continuous reinforcement typically results in faster adoption of the “good” behavior by the subject than any other reinforcement schedule, as the subject is rewarded every time he or she completes the behavior.
Identify the reinforcement schedule illustrated below.
A voice says “good job” every tenth time a research subject correctly places a ball on the desired target.
Fixed-ratio reinforcement
This is when subject behavior is rewarded every nth time (i.e. after some predetermined, fixed number of responses).
Identify the reinforcement schedule illustrated below.
A voice says “good job” every tenth time a patient correctly places the ball on the desired target for 10 minutes of play, then every fifth time for 5 minutes, then every eighth time for 10 minutes.
Variable-ratio reinforcement
A variable-ratio schedule provides reinforcement after an unpredictable (sometimes random) number of responses. This schedule creates a steady, high rate of responding (e.g. gambling, slot machines).
Identify the reinforcement schedule illustrated below.
A virtual reality motor rehabilitation game is designed to have a voice say “good job” in response to the very next correct behavior that occurs after each 5-minute period.
Fixed-interval reinforcement
This type of schedule provides reinforcement only after a specified, consistent amount of time has elapsed.
Identify the reinforcement schedule illustrated below.
A virtual reality motor rehabilitation game is designed to have a voice say “good job” in response to a correct behavior every n minutes, where n is a random number chosen from the values [1, 2, 3, 4, 8].
Variable-interval reinforcement
This type of schedule provides reinforcement after specific (but variable and unpredictable) amounts of time have passed.
________ reinforcement produces faster learning than any other reinforcement schedule, but ________ reinforcement is much more resistant to extinction.
For each blank, choose from continuous, fixed-ratio, or variable-ratio.
Continuous reinforcement produces faster learning than any other reinforcement schedule, but variable-ratio reinforcement is much more resistant to extinction.
Continuous reinforcement involves rewarding every instance of the desired behavior, which leads to quick adoption of the behavior. However, if one wants the subject to retain the behavior long after reinforcement has ceased (in other words, if the behavior needs to be resistant to extinction), then variable schedules, such as variable-ratio reinforcement, are superior to all others.
A child is observed to sit in his chair doing nothing, then finish multiple math problems in a row approximately every five minutes. What reinforcement schedule is the child most likely to be experiencing?
Fixed-interval reinforcement
In fixed-interval schedules, the subject quickly figures out the duration of the interval and tends to perform the desired behavior toward the end of that interval. In this example, the interval is likely five minutes.
In the context of operant conditioning, what is the difference between positive and negative?
Positive refers to the addition or administration of a stimulus, while negative refers to the removal of a stimulus.
Make sure to avoid ascribing any “good” vs. “bad” meaning to these terms! While “positive” and “negative” may mean “good” and “bad” in conversation, they do not share that meaning in this context.
In the context of operant conditioning, what is administered to incentivize a subject to continue performing a behavior?
Reinforcement
Reinforcement refers to a response (such as a reward) that is administered to encourage a desired behavior.
In the context of operant conditioning, what is administered to decrease the frequency of an undesired behavior?
Punishment
The aim of punishment is to discourage the subject from performing a behavior. We are all familiar with real-life examples, such as putting a noisy child in a time-out.
Identify the operant conditioning scenario illustrated below.
A child gets a gold star sticker for each word spelled correctly on a weekly quiz.
Positive reinforcement
This involves administering (positive) a reward in an attempt to encourage a desired behavior (reinforcement).
Identify the operant conditioning scenario illustrated below.
Students in the U.S. Navy Strike Fighter Tactics Instructor program are fined $5 every time they quote the movie Top Gun.
Negative punishment
This involves removing (negative) a reward in an attempt to discourage an unwanted behavior (punishment).
This story about Top Gun is reportedly true, although who really knows what is true on the Internet.
Identify the operant conditioning scenario illustrated below.
A child picks his nose during dinner, and his mother chides him in front of the family.
Positive punishment
This involves administering (positive) an unwanted consequence in an attempt to discourage an unwanted behavior (punishment).
Identify the operant conditioning scenario illustrated below.
A cross-country coach lets his runners skip one sprint for each time they do a good deed (such as thanking the bus driver or picking up trash).
Negative reinforcement
This involves removing (negative) an adverse consequence in an attempt to encourage a desired behavior (reinforcement).
Identify the operant conditioning scenario illustrated below.
A 6-year-old is not listening to her babysitter and is acting inappropriately. The babysitter decides to take away a cookie from snack time for each incident of misbehavior.
Negative punishment
This occurs when a specific desired stimulus (the cookie) is removed after a undesired behavior is exhibited, intending to make it so the behavior happens less often.
What is the difference between escape and avoidance?
Escape refers to taking an action to remove oneself from an adverse stimulus that is already occurring.
Avoidance refers to taking an action to prevent an adverse stimulus before it has occurred.
Clara foolishly volunteers for a study in which she is paid $10 to experience a consistent electric shock, which stops once she has answered five questions correctly. Soon, she is answering questions at a rapid pace, exemplifying:
Choose from escape learning, avoidance learning, or neither.
escape learning.
Since the electric shock in this study persists until the subject takes an action (answering questions correctly), the reward is escape from the shock, constituting escape learning.
Learning to swerve slightly to miss a nasty pothole on one’s commute to work constitutes what form of learning?
Choose from escape learning, avoidance learning, or neither.
Avoidance learning
Since the individual is learning to avoid the adverse stimulus (the feeling of hitting a pothole) before it is encountered, this is avoidance learning.
Escape and avoidance learning both occur as a result of:
Choose from positive punishment, negative punishment, positive reinforcement, or negative reinforcement.
negative reinforcement.
Negative reinforcement refers to rewarding a behavior through the removal (escape from) or avoidance of an adverse stimulus.
A researcher is designing an operant conditioning study in which rats are rewarded for button presses with treats. How is the researcher likely to ensure that the rats are sufficiently motivated by the treats?
The researcher will deprive the rats of food for a period of time.
This is certainly sad, but it avoids the possibility of confusing the experimental results by using overstuffed rats who just don’t want more food. Starving the rats is a way to operationalize (define/put into reality) the more abstract concept of motivation in this experiment.
Define:
shaping
Shaping refers to the process of successively rewarding behaviors that are closer and closer to a complex desired behavior.
Shaping is particularly relevant with animal training. If I am training my dog to jump through a series of hoops, I might first reward him for walking through one hoop, then for jumping through that hoop, and finally for jumping through multiple hoops.
Is shaping more closely related to operant or classical conditioning?
Shaping is a form of operant conditioning.
We know this to be true because shaping relies on conscious learning of voluntary behaviors that are then reinforced. This differs from classical conditioning, which deals with largely unconscious learning resulting from paired stimuli.
A student is at work, passively listening to the sound of an MCAT video about an unfamiliar science concept. If the student later finds that he answers nearly every question on the topic correctly in a practice set, he has undergone _________ learning.
latent
Latent learning is passive learning that takes place without clear reinforcement. This means that learning is occurring, but it is not observed until some reinforcement or incentive is introduced (e.g. the reinforcement implicit in completing practice questions accurately) to demonstrate it.
What broad term refers to organized methods implemented to find solutions to problems?
Problem solving
Problem solving includes methodical thought processes that are specifically aimed at finding solutions to given problems.
Name the problem-solving method that involves repeatedly attempting solutions (sometimes almost at random) until one finally works.
Trial and error
Note that trial and error is also relevant in the context of cognition.
A dog is conditioned to sit quietly when a stranger enters its owner’s front door. If, under stress, the dog ignores its learned behavior and reverts back to its primal nature, barking at a man who opens the door, this dog has exhibited:
instinctual drift.
This is the tendency of an animal to revert to instinctive behaviors that interfere with a conditioned response.
Learning a new behavior by watching others engage in that behavior is termed:
observational learning.
While observational learning is particularly relevant in the context of children, adults engage in it as well.
Supporters of the concept of _________ learning would expect kind, loving families to give rise to kind, loving adults and cruel, apathetic families to give rise to cruel, apathetic adults.
observational
This is learning which occurs through observation (e.g. modeling) of the behavior of those around you.
The most famous experiment involving observational learning was conducted by psychologist Albert Bandura. Name this experiment.
The Bobo doll experiment
In this study, children observed adults beating and abusing an inflatable doll. Depending on the specifics of the situation, the children were later seen to engage in similar abusive behavior, indicating that observational learning had taken place.
One of the benefits of school for young children, aside from education, is that the child can learn to socialize properly by watching others and imitating how they behave. Which method of observational learning is occurring in school?
Modeling
This is a form of learning where individuals ascertain how to act or perform by observing another individual. For example, a boy may learn to tie a tie or shave by watching his father or older brothers do it.
Name the neurons that fire both when a person performs an action and when the person watches someone else perform that action.
Mirror neurons
These neurons play a crucial role in observational learning. They also are thought to influence common real-world phenomena, such as our urge to yawn when we see another person yawning.
Which of the following emotions is most closely tied to the actions of mirror neurons?
- Anger
- Happiness
- Sympathy
- Empathy
Empathy
Empathy is the experience of understanding another’s condition from their perspective: placing oneself in another’s shoes and feeling what they are feeling. Even though the event is not happening to you, you may experience similar reactions, which is tied to the firing of mirror neurons.
While watching a coronary artery bypass graft for the first time, a med student feels an exhilarating sensation and excitement as the surgeon performs her task. The student’s feelings are an example of ________ emotion.
vicarious
Vicarious emotions are emotions that one feels while watching another person experience an event without actually having experienced a similar event themselves (if they had, it would be empathy). Both empathetic emotions and vicarious emotions are highly useful in social interactions.
