Exp Brain Res (2011) 214:427–435 DOI 10.1007/s00221-011-2841-6 R E S E A R C H A R T I C L E Spatial and nonspatial implicit motor learning in KorsakoV’s amnesia: evidence for selective deWcits Ilse A. D. A. Van Tilborg · Roy P. C. Kessels · Pauline Kruijt · Arie J. Wester · Wouter Hulstijn Received: 5 January 2011 / Accepted: 9 August 2011 / Published online: 19 August 2011 © The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Patients with amnesia have deWcits in declara- tive memory but intact memory for motor and perceptual skills, which suggests that explicit memory and implicit memory are distinct. However, the evidence that implicit motor learning is intact in amnesic patients is contradictory. This study investigated implicit sequence learning in amne- sic patients with KorsakoV’s syndrome (N = 20) and matched controls (N = 14), using the classical Serial Reac- tion Time Task and a newly developed Pattern Learning Task in which the planning and execution of the responses are more spatially demanding. Results showed that implicit I. A. D. A. Van Tilborg (&) Department of Medical Psychology, ZGT Hospital, PO Box 7600, 7600 SZ Almelo, The Netherlands e-mail: i.vtilborg@zgt.nl I. A. D. A. Van Tilborg Elkerliek Hospital, Helmond, The Netherlands I. A. D. A. Van Tilborg · R. P. C. Kessels · W. Hulstijn Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, The Netherlands R. P. C. Kessels Departments of Medical Psychology and Geriatric Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands R. P. C. Kessels · A. J. Wester KorsakoV Clinic, Vincent van Gogh Institute for Psychiatry, Venray, The Netherlands P. Kruijt Sarr Centre for Autism, Parnassia Bavo Psychiatric Institute, Rotterdam, The Netherlands W. Hulstijn Collaborative Antwerp Psychiatric Research Institute (CAPRI), University of Antwerp, Antwerp, Belgium motor learning occurred in both groups of participants; however, on the Pattern Learning Task, the percentage of errors did not increase in the KorsakoV group in the random test phase, which is indicative of less implicit learning. Thus, our Wndings show that the performance of patients with KorsakoV’s syndrome is compromised on an implicit learning task with a strong spatial response component. Keywords KorsakoV’s syndrome · Amnesia · Implicit learning · Motor learning · Sequence learning · Memory Introduction Multiple memory systems are postulated to underlie the diVerences in memory performance of distinct patient groups. For example, Squire (1992) distinguished between explicit or declarative memory and implicit or nondeclara- tive memory. The memory proWle of patients with amnesic syndrome, which is characterized by deWcits in declarative memory and intact memory for motor and perceptual skills, supports this distinction. (Schacter 1987; Squire and Zola- Morgan 1988). However, recent evidence suggests that implicit memory is not unconditionally spared in patients with amnesia and that in these patients, visual feedback is critical for the successful mastery of implicit movement sequences (Swinnen et al. 2005). The participants of the present study were patients with KorsakoV’s syndrome, a disorder characterized by profound anterograde amnesia and severe, temporally graded, retro- grade amnesia (Kopelman 2002). Their amnesia is a result of damage in the diencephalon, notably the mammillary bodies and thalamus (Kopelman 2002). These areas are thought to be critical for episodic memory formation, since they are 123