Previous errorless sequence-learning promotes subsequent SRT performance in patients with Alzheimer's Disease

Motor-learning capacities are known to be relatively preserved in Alzheimer's disease (AD), which is crucial in the context of the patient’s autonomy (e.g., Rouleau et al., 2002). However, it is important to determine the most appropriate techniques for such learning. In AD, implicit or procedural rehabilitation techniques would be more effective to train new skills than explicit or declarative learning methods (van Halteren-van Tilborg, 2007). Maxwell et al. (2001) showed that reducing errors during motor learning minimizes the building of declarative knowledge and would allow implicit knowledge accumulation. If errorless learning induces the formation of an implicit knowledge, this technique appears to be adapted to the learning of a perceptual-motor skill in patients with impaired controlled processes. Very few studies have investigated errorless learning in procedural learning situations, even though some data suggest that errorless learning would be efficient for learning instrumental activities of daily living (e.g., Thivierge et al., 2008).
In this study we examined the acquisition of a new perceptual-motor skill in 12 patients with AD and 12 healthy older adults. We compared the impact of two preliminary sequence learning conditions (errorless vs. errorful) on a serial reaction time (SRT) performance. In SRT, the subject must react as quickly as possible to the appearance of a target on a screen by pressing the key corresponding to the position of the stimulus. The effectiveness of learning is demonstrated by a reaction time improvement when the target follows a repeating sequence.
For patients with AD, results confirm that the advantage provided by prior learning occurs only in the errorless condition whereas both learning modes improve SRT performance in healthy participants.
In conclusion, these results confirm that the errorless learning promotes the development of implicit knowledge and appears to be an effective method for procedural learning in Alzheimer's disease.