Applied behavior analysis (ABA) looks at learning in terms of four rather distinct levels. These levels affect how completely behaviors are learned and should dictate how specific ABA procedures are utilized. One of the primary criticisms of using ABA is that it results in non-functional, prompt specific, rote responses. Unfortunately, this can occur when the procedures are implemented without regard for each level of learning. To the contrary, when teaching occurs through all four learning levels, the result is the development of a behavioral repertoire that is meaningful and functional in everyday life.
First Learning Level: Acquisition
Acquisition is the very beginning of the learning process. It is the initial introduction of a new behavior whereby significant assistance and a high rate of reinforcement are provided. The goal of teaching at the first learning level is to establish a desired response.
Example: Brushing teeth occurs.
Second Learning Level: Fluency
Fluency refers to the rate at which a behavior occurs. At this level of learning, assistance begins to decrease and reinforcement is given only when the behavior is demonstrated within a designated period of time.
Example: Brushing teeth occurs within three minutes.
Third Learning Level: Maintenance
Maintenance is achieved when re-teaching and reinforcement are no longer required in order for a behavior to occur appropriately. It is at this level of learning that behavior starts to become useful in everyday life.
Example: Brushing teeth occurs independently within three minutes and in the absence of reinforcement.
Fourth Learning Level: Generalization
Generalization occurs when a behavior can be demonstrated in a variety of circumstances. That is, the behavior occurs correctly with different people, using a variety of materials in different locations, and in response to different directions.
Example: Brushing teeth occurs independently within three minutes in the absence of reinforcement at different locations and with a variety of people, materials, and instructions.
Excerpt from Autism and ABA: A "How-To" Handbook for Teachers