title: Replay of very early encoding representations during recollection.
abstract: Long-term memories are linked to cortical representations of perceived events, but it is unclear which types of representations can later be recollected. Using magnetoencephalography-based decoding, we examined which brain activity patterns elicited during encoding are later replayed during recollection in the human brain. The results show that the recollection of images depicting faces and scenes is associated with a replay of neural representations that are formed at very early (180 ms) stages of encoding. This replay occurs quite rapidly, ~500 ms after the onset of a cue that prompts recollection and correlates with source memory accuracy. Therefore, long-term memories are rapidly replayed during recollection and involve representations that were formed at very early stages of encoding. These findings indicate that very early representational information can be preserved in the memory engram and can be faithfully and rapidly reinstated during recollection. These novel insights into the nature of the memory engram provide constraints for mechanistic models of long-term memory function.
authors.affiliation: Institute of Cognitive Neuroscience, University College London, London WC1N 3AR, United Kingdom; Institute of Cognitive Neurology and Dementia Research, Medizinische Fakultät, 39120 Magdeburg Otto-von-Guericke, Germany; Cognition and Brain Plasticity Unit, Institute of Biomedicine Research of Bellvitge, Hospital Duran i Reynals, 08908 Hospitalet de Llobregat, Barcelona, Spain; Department of Basic Psychology, University of Barcelona, Secretaria 08035 Barcelona, Spain; and Institute of Neurology and Wellcome Trust Centre for Neuroimaging, University College London, London WC1N 3BG, United Kingdom.
authors.forename: Anna
authors.initials: A
authors.lastname: Jafarpour
authors.forename: Lluis
authors.initials: L
authors.lastname: Fuentemilla
authors.forename: Aidan J
authors.initials: AJ
authors.lastname: Horner
authors.forename: Will
authors.initials: W
authors.lastname: Penny
authors.forename: Emrah
authors.initials: E
authors.lastname: Duzel
mesh_terms: D000328:Adult; D005260:Female; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods; D008297:Male; D057567:Memory, Long-Term / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods*; D011597:Psychomotor Performance / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult