Intact Implicit Learning in Schizophrenia

Abstract

Implicit learning, as assessed with an artificial grammar learning task, is intact in patients with schizophrenia. Conscious awareness might be a critical determinant of memory impairment both at encoding and at retrieval.

Conscious and subliminal conflicts in normal subjects and patients with schizophrenia: The role of the anterior cingulate

“…Interestingly, only backward masking is impaired whereas forward masking, which is thought to be based on retinal and cortical bottom-up mechanisms, remains intact (41). Patients with schizophrenia also exhibit a dissociation between impaired explicit recollection and normal implicit memory (36)(37)(38). Together with evidence for impaired awareness of self-generated action (47), those results converge to suggest that a core deficit in schizophrenia concerns a distributed cortical conscious monitoring system that involves the ACC as a crucial node (48,49).…”

“…This predicted dissociation of subliminal and conscious processing in schizophrenia has not been studied directly in the literature (but see refs. [34][35][36][37][38]. Given the evidence for multiple, distributed sites of brain dysfunction in schizophrenia, including ACC and PFC, the finding of preserved subliminal priming would provide strong evidence that ACC and PFC are not involved in automatic conflict resolution, but solely in conscious monitoring.…”

A systematic review on improving cognition in schizophrenia: which is the more commonly used type of training, practice or strategy learning?

“…While explicit learning impairments have been consistently reported in schizophrenia literature [15,16], there is still a debate over impairments to implicit learning. For example, some studies report that implicit learning is intact for tasks such as probabilistic classification learning (e.g., [17]), weather prediction (e.g., [18]), and artificial grammar learning (e.g., [19]), while others report an impairment in colour pattern learning but not in letter string learning [20]. Adding to this conundrum are a variety of different training procedures currently being tested, both for drill and strategy (includes explicit and implicit learning) and for drill and practice (implicit learning only).…”

Cognitive Remediation for Schizophrenia

“…In contrast to conventional trial and error learning, which requires the learner to remember and incorporate feedback, errorless learning is based on repetitive exposure designed for the learner to succeed in a majority of trials, with difficulty gradually increasing as the learner develops mastery. Errorless learning takes advantage of implicit (learning without conscious awareness) learning processes that may be intact in schizophrenia; 84,85) treatment induced improvements in implicit learning systems may thus help to restore impaired working memory and explicit memory processes. 58) Errorless learning has been demonstrated to be effective in schizophrenia patients in both formal memory assessments and a study of work performance carried out in a community mental health center setting.…”