The existence of a central executive function in the brain has been theorized.  It's function being the control of working memory, or scratch pad memory but also the integration of information from both the visuo-spatial and auditory loops.  While H.M. retained working memory, DAT patients show difficulty in advanced stages of the disease with focusing attention, staying on task, and comprehending instructions.  Researchers have called attention to the cognitive burdens that passive verbs, dual objects, and even unnaturally slowed speech may present. These difficulties should not be confused with a total inability to recognize, reason, or feel emotions.  In fact, the ability to recognize and respond, if not interpret, visual and auditory cues as triggers to procedural behavior suggests that the environment, including other people in it, can serve in effect as externalized memory for the patient.  It is important to remain conscious of ways to unburden working memory.  Relying on auditory perceptual cues coupled with singular visual cues is one strategy while minimal distractions and error-free learning are two more strategies.  These will be described further as they have been employed in the prototype described below in Design Decisions and Strategies.