Discrimination means that a behavior occurs in the presence of one stimulus and not in the presence of another stimulus, because that behavior has a history of reinforcement in the presence of that specific stimulus that has not occurred in the presence of other stimuli.
Discrimination training is the process of reinforcing a target response only when the target antecedent, or SD, is present. It is used to teach the patient the difference between two or more stimuli.
EXAMPLEWhen engaging in naming behavior, a learner calls an apple “apple,” and does not call other stimuli “apple.” The learner comes to do this because they have received praise in the past from a teacher when they called an apple “apple,” and they did not receive praise when they called other stimuli “apple.”
We've got these. What color is this?
Red, very good. You know your colors.
What color is this?
EXAMPLEThe telephone is a classic example of discrimination in daily life. The sound of the phone ringing is the SD that signals that the behavior of answering the phone will result in the reinforcer of being able to speak to someone. If the same behavior (picking up the phone) occurs when the phone is not ringing, it will not get that reinforcer.
Teaching discrimination is fundamental for patients with autism spectrum disorder (ASD) because virtually all complex behavior involves discrimination of some sort. Accordingly, many types of discrimination must be taught, and many ways exist to teach them.
There are several key terms that you will need to be familiar with in order to fully understand discrimination training.
The term acquisition target is used to describe the SD-Response relationship that is currently being taught.
The acquisition target is something the patient has not yet learned and that is in the process of being taught. It is typically identified by the BCBA using some type of assessment. A response or SD/instruction that the individual is currently learning is said to be “on acquisition.” The acquisition target is sometimes shortened to just “target.”
EXAMPLEIf the patient is learning to identify a banana, the banana is the acquisition target.
The term distracter refers to additional items that are not targets, but are used in discrimination training to teach discrimination. Distracter items can be known or unknown to the patient.
EXAMPLEIf the patient is learning to identify a banana, the banana is the acquisition target and apple and orange are the distracters. The same SD is given each trial, but different items can be used as distracters along with the acquisition target.
The term mass trial refers to repeating a specific SD/instruction to practice giving a correct response.
It is often used to introduce a new skill within errorless learning procedures. The same instruction or SD is presented repeatedly.
EXAMPLEOn the first trial, you might ask a patient to touch their head. Then, on the second trial, you would present the same instruction, and again on the third trial, and so on, until some criterion has been met.
Some believe that mass trialing is crucial to early discrimination learning, whereas others believe that it is rarely, if ever, helpful. The rationale for why mass trials may not be helpful is that, by definition, they do not require a discrimination; they merely require the patient to repeat what they just did a second earlier. The rationale for why they are helpful is that they make the task as easy as possible and, therefore, provide maximum opportunity for reinforcement and maximum practice on new targets.
Red. [TOKEN CLACKS]
There it is! Good job.
Wow, that was great.
Random rotation is the presentation of two or more SDs in random order. This technique is used to ensure that a patient can discriminate between two or more SDs or instructions.
Random rotation is a procedure during which trials of the same target are not repeated in succession.
EXAMPLEYou might ask a patient to touch their head on the first trial, to touch their nose on the second trial, and to touch their ears on the third trial, and subsequent trials would randomly select from the three targets.
In other words, random rotation requires the patient to choose between a stimulus that is currently being taught and one or more other stimuli.
You ready to go?
You did it!
Oh my goodness. That was so good!
The last key term is mastery criteria, which means criteria that objectively demonstrate that an individual has learned a target. Mastery criteria are set for each patient by the BCBA.
EXAMPLEAn example of a mastery criteria could be demonstrating the skill two times at 80% or better in random rotation with a first trial correct. This might be written as 2x80% ≥ in RR.