title: Neural Global Pattern Similarity Underlies True and False Memories.
abstract: The neural processes giving rise to human memory strength signals remain poorly understood. Inspired by formal computational models that posit a central role of global matching in memory strength, we tested a novel hypothesis that the strengths of both true and false memories arise from the global similarity of an item's neural activation pattern during retrieval to that of all the studied items during encoding (i.e., the encoding-retrieval neural global pattern similarity [ER-nGPS]). We revealed multiple ER-nGPS signals that carried distinct information and contributed differentially to true and false memories: Whereas the ER-nGPS in the parietal regions reflected semantic similarity and was scaled with the recognition strengths of both true and false memories, ER-nGPS in the visual cortex contributed solely to true memory. Moreover, ER-nGPS differences between the parietal and visual cortices were correlated with frontal monitoring processes. By combining computational and neuroimaging approaches, our results advance a mechanistic understanding of memory strength in recognition.
  
  
  
  What neural processes give rise to memory strength signals, and lead to our conscious feelings of familiarity? Using fMRI, we found that the memory strength of a given item depends not only on how it was encoded during learning, but also on the similarity of its neural representation with other studied items. The global neural matching signal, mainly in the parietal lobule, could account for the memory strengths of both studied and unstudied items. Interestingly, a different global matching signal, originated from the visual cortex, could distinguish true from false memories. The findings reveal multiple neural mechanisms underlying the memory strengths of events registered in the brain.
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, PR China, Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, 100875, China.
authors.forename: Zhifang
authors.identifier: 0000-0003-0489-2619
authors.initials: Z
authors.lastname: Ye
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, PR China, Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, 100875, China.
authors.forename: Bi
authors.initials: B
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, PR China, Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, 100875, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Zhuang
authors.affiliation: Department of Psychology, Ohio State University, Columbus, Ohio 43210, and.
authors.forename: Zhonglin
authors.identifier: 0000-0002-7295-727X
authors.initials: Z
authors.lastname: Lu
authors.affiliation: Department of Psychology and Social Behavior, University of California, Irvine, California 92697.
authors.forename: Chuansheng
authors.identifier: 0000-0002-8224-1005
authors.initials: C
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, PR China, Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, 100875, China, guixue@gmail.com.
authors.forename: Gui
authors.identifier: 0000-0001-7891-8151
authors.initials: G
authors.lastname: Xue
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D011939:Mental Recall; D010100:Oxygen / Q000097:blood; D012094:Repression, Psychology; D012660:Semantics; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: DRM; fMRI; false memory; global matching models; neural global pattern similarity; recognition