The ISAAC System is a small, wearable, individualized cognitive prosthetic designed for use by individuals with cognitive disabilities, brain injury, stroke, or developmental disabilities such as mental retardation, dementia, and pseudo-dementia. 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 system user's individualized prompting and information content is developed by a rehabilitation specialist or other professional using authoring tools 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 and may be behavioral, procedural, reminders, and other types. Content can be updated as needed based on the user's changing needs and situation. Information content can be presented 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 and employment situations, and in combinations of these. POWER: Uses long-life rechargeable batteries designed to last all day and recharge overnight.