Spatial and nonspatial implicit motor learning in KorsakoV’s amnesia: evidence for selective deWcits

Patients with amnesia have deWcits in declarative 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 amnesic patients with KorsakoV’s syndrome (N = 20) and matched controls (N = 14), using the classical Serial Reaction 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 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.