Single-component microcomputer-driven assessment of attention

The Gordon Diagnostic System (GDS) is a single-component microcomputer-based instrument that can be used to administer 11 psychological tests. The game-like tasks provide objective data for evaluating possible attention-deficit hyperactivity disorder or other conditions that affect a person’s ability to sustain attention and exert self-control. The core of the instrument is an integrated circuit with a microprocessor, a random access memory, and an erasable, programmable read-only memory (EPROM). It can be programmed with an IBM PC and an EPROM programmer. The assembly language source is compiled into machine language, which is used to simulate the GDS on the IBM PC or is “burned” into the ROM. The memory is erasable with ultraviolet light, so revisions can be made easily. The GDS illustrates that “custom” programming a ROM is not limited to large industrial concerns, and that it can be done within small research groups.