title: Retrieval induces adaptive forgetting of competing memories via cortical pattern suppression.
abstract: Remembering a past experience can, surprisingly, cause forgetting. Forgetting arises when other competing traces interfere with retrieval and inhibitory control mechanisms are engaged to suppress the distraction they cause. This form of forgetting is considered to be adaptive because it reduces future interference. The effect of this proposed inhibition process on competing memories has, however, never been observed, as behavioral methods are 'blind' to retrieval dynamics and neuroimaging methods have not isolated retrieval of individual memories. We developed a canonical template tracking method to quantify the activation state of individual target memories and competitors during retrieval. This method revealed that repeatedly retrieving target memories suppressed cortical patterns unique to competitors. Pattern suppression was related to engagement of prefrontal regions that have been implicated in resolving retrieval competition and, critically, predicted later forgetting. Thus, our findings demonstrate a cortical pattern suppression mechanism through which remembering adaptively shapes which aspects of our past remain accessible.
authors.affiliation: 1] School of Psychology, University of Birmingham, Birmingham, UK. [2] MRC Cognition and Brain Sciences Unit, Cambridge, UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Wimber
authors.affiliation: MRC Cognition and Brain Sciences Unit, Cambridge, UK.
authors.forename: Arjen
authors.initials: A
authors.lastname: Alink
authors.affiliation: MRC Cognition and Brain Sciences Unit, Cambridge, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: Charest
authors.affiliation: MRC Cognition and Brain Sciences Unit, Cambridge, UK.
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Kriegeskorte
authors.affiliation: 1] MRC Cognition and Brain Sciences Unit, Cambridge, UK. [2] Behavioural and Clinical Neurosciences Institute, Cambridge, UK.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Anderson
mesh_terms: D000223:Adaptation, Psychological / Q000502:physiology*; D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D003463:Cues; D005260:Female; D006624:Hippocampus / Q000502:physiology; D006801:Humans; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology; D055815:Young Adult