When should mass trials be used in Discrete Trial Training (DTT)?

Mass trials are employed in Discrete Trial Training (DTT) primarily to promote discrimination between different stimuli or responses. The use of mass trials allows practitioners to focus on a single target behavior or response with multiple opportunities for the learner to practice. By presenting the same stimulus repeatedly, it gives the individual a chance to learn to discriminate between that specific target and potential distractors in future trials.

The goal of promoting discrimination is to ensure that the learner can identify or respond correctly to the target behavior consistently, which is essential for building skills effectively. By concentrating on one item or skill, it helps the individual to solidify their understanding and ability before moving on to more varied trials where generalization of skills can occur.

In DTT, once the learner shows mastery of a particular skill through mass trials, this can then lead to more varied trials, which would incorporate a mix of targets to encourage further discrimination and application of skills. Therefore, while other options may relate to different aspects of training or reinforcement, the primary focus of mass trials is to promote effective discrimination, making it the correct choice in this scenario.