Empirically valid principles for training in the real world

Four sets of cognitive psychology experiments are aimed to identify and empirically support principles of training intended to increase training effectiveness. Each set supports a different training principle: strategic use of knowledge (learning and memory are facilitated whenever preexisting knowledge can be used as a mediator in the process of acquisition), training difficulty (conditions that cause desirable difficulties during learning might facilitate later retention and transfer), mental practice (mental practice can retard forgetting and promote transfer of training, sometimes to a larger extent than can physical practice), and cognitive antidote (adverse effects of prolonged work on routine tasks can be mitigated by adding cognitive complications). The first 2 principles are focused on knowledge acquisition and the last 2 on skill acquisition. Nevertheless, the principles converge on similar prescriptions: Contrary to intuition and common practice, the trainer is recommended to increase the complexity of the training situation rather than use the simplest methods available.