Applied Behavior Analysis Technician (ABAT) Practice Test

What defines an unconditioned reinforcer?

1. A previously neutral stimulus

2. A stimulus that requires pairing to increase behavior

3. A stimulus change that increases behavior without prior pairing

4. A reinforcer that diminishes over time

The correct answer is: A stimulus change that increases behavior without prior pairing

An unconditioned reinforcer is identified as a stimulus change that increases behavior without the need for prior conditioning or pairing. This type of reinforcer is inherently effective due to biological factors and does not depend on learning or experience. Classic examples of unconditioned reinforcers include things like food, water, and warmth, which naturally enhance the likelihood of certain behaviors occurring—such as seeking food when hungry. The other answer choices do not align with the definition of an unconditioned reinforcer. A previously neutral stimulus would describe a conditioned reinforcer, because it gains its reinforcing properties through pairing with an established reinforcer. A stimulus requiring pairing to increase behavior also describes conditioned reinforcers, as they acquire their effectiveness only after being associated with an unconditioned reinforcer. A reinforcer that diminishes over time may refer to a phenomenon like satiation but does not capture the essence of an unconditioned reinforcer, which typically maintains its effectiveness as a biological necessity.