Prior to stroke, upper arm functions such as reaching and grasping were largely done without the use of explicit knowledge. In other words, healthy individuals devote little conscious effort about how they are controlling their limbs, they just 'do it'. Although, using explicit strategies during learning can facilitate the rate of learning, if given enough time, individuals who have limited explicit knowledge will perform equally well (Maxwell et al, 1999). Despite a slower rate of learning, the payoff of reducing explicit knowledge of the task can be very advantageous during motor performance. Notably, retention of the learned behavior is greater in individuals who learned under conditions that inhibit explicit knowledge. For example Malone and Bastian (2010) had individuals learn a novel walking task (split belt treadmill where the belts move at different rates) and in those in which explicit knowledge was limited exhibited learning that persisted longer than those who relied on explicit knowledge during learning. In addition, limiting explicit knowledge during motor learning may result in reduced cognitive workload and maintained performance under conditions of challenge (Zhu et al., 2011). In conclusion, promoting explicit knowledge during rehabilitation rather than unconscious control (limiting explicit knowledge) reduces sustainability of the newly acquired motor skill, and consumes cognitive resources, which need to be available for other demands. As such, automatic control of these behaviors is critical to perform daily activities, suggesting operant conditioning (which limits explicit knowledge) as superior to error-based learning.