On-the-job training requires considerable independence on the part of the trainee. Unlike a student in a classroom, the trainee must arrange information resources in such a way that he can learn how to perform his specific task without wasting valuable time reading irrelevant information. He must further direct this learning himself. A computer-based aid to self-directed learning has been developed to meet this need. This aids system is implemented on the PLATO system and uses the touch-panel capability of the PLATO-IV terminal. Students are presented with a task which requires complex learning, and they are given considerable information -- much more than is needed, in fact -- to attain the task. The aids system is designed to allow students to break down their task into a set of more easily attained objectives, to decide when information is relevant to their objectives, and in general to monitor their progress toward achieving the task.

Procedural semantics models have diminished the distinction between data structures and procedures in computer simulations of human intelligence. This development has theoretical consequences for models of cognition. One type of procedural semantics model, called schema theory, is presented, and a variety of cognitive processes are explained in terms of the theory. In schema theory, the flow of processing control is determined not by a central monitor, but by interactions among the conceptual entities (schemata) that make up the model. Intelligence is distributed in this model. Schemata interact by providing activation resources to each other. Instantiation is the special process whereby a partial copy of a strongly activated schema is created. In this copy, the variables of the schema are filled with particular values. Such copies make up specific or episodic memory. The schemata on which they are based comprise generic or semantic memory. Many of the phenomena of consciousness and of short-term and long-term memory are explained on the basis of the activation processes of schema theory. Unactivated schemata are equivalent to all the unconscious knowledge in a person's long-term memory. Three dimensions for distinguishing or comparing schemata are proposed; function, abstractness, and scope. The contrasts between multi-store models of cognition and schema theory are summarized.

Two different uses of interactive graphics in CAI are described. Interactive graphics may be used as substitutes for physical devices and operations. An example is simulation of operating on man/machine interfaces, substituting interactive graphics for controls, indicators, and indications. Interactive graphics may also be used to explicate invisible processes. Examples are interactive graphics that allow the student to initiate animations of physical processes and interactive block diagrams that allow the student to learn the functional organization of complex devices. Projects are underway to test the effectiveness of these uses. (Author).