The ISAAC System is a small, wearable, individualized cognitive aid and prompter designed for use by individuals with cognitive disabilities, brain injury, stroke, developmental disabilities such as mental retardation, dementia, and pseudo-dementia. ISAAC attaches to the user's belt and features a small touchscreen that displays messages and prompts that the user acknowledges by touching. Because it is fully individualized and easy to use, categorically oriented, ISAAC is suitable for individuals with a variety of cognitive and memory disabilities. Each user's individualized prompting and information content is developed by a rehabilitation specialist or other professional using ISAAC Author (see separate entry), an authoring program provided by Cogent Systems, Inc. Content may include such items as prompts delivered at specified times or under specified conditions, task steps, directions to and from places, personal information, reminders, and more. Prompts are delivered to the user as synthesized speech audio in English or Spanish and may be behavioral, procedural, reminders, and other types. ISAAC logs performance data so that a rehabilitation specialist or other professional can analyze how the user responds to prompts and adjust the content accordingly. Content can be updated as needed based on the user's changing needs and situation. Information content can be presented in English or Spanish as text, checklist, graphics, or synthesized speech audio output. The system eliminates the need for the user to type anything or remember key words; reminders of available content are shown on the system display and selections are made on the device touch screen. The system is designed to be worn throughout the day and to be used while being worn, making it accessible at all times. It also frees the user's hands for activities of daily living, including employment, while the system is being used and reduces the possibility of loss or theft. The system is appropriate for use in independent or supported living situations and in the workplace. POWER: Uses rechargeable batteries designed to last all day and recharge overnight while in the ISAAC; expected battery life is 2 years.