Characterizing the Neuro-Cognitive Architecture of Non-Conscious Working Memory Darinka Trübutschek

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Characterizing the Neuro-Cognitive Architecture of Non-Conscious Working Memory Darinka Trübutschek Characterizing the neuro-cognitive architecture of non-conscious working memory Darinka Trübutschek To cite this version: Darinka Trübutschek. Characterizing the neuro-cognitive architecture of non-conscious working mem- ory. Cognitive Sciences. Sorbonne Université, 2018. English. NNT : 2018SORUS101. tel-02956592 HAL Id: tel-02956592 https://tel.archives-ouvertes.fr/tel-02956592 Submitted on 3 Oct 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Université Pierre et Marie Curie Ecole doctorale Cerveau, Cognition et Comportement Inserm-CEA Cognitive Neuroimaging Unit (Unicog, Neurospin) CHARACTERIZING THE NEURO-COGNITIVE ARCHITECTURE OF NON-CONSCIOUS WORKING MEMORY Darinka TRÜBUTSCHEK Dissertation submitted in partial fulfillment for the degree of Doctor in Philosophy (PhD) in Cognitive Neuroscience Advised by Prof. Stanislas DEHAENE and co-advised by Dr. Sébastien MARTI Presented and publically defended on the 1st of October 2018 In front of a jury and invited members composed of: Prof. David SOTO Basque Center on Cognition, Brain, and Language Reviewer Prof. Mark STOKES University of Oxford Reviewer Prof. Paolo BARTOLOMEO Institut du Cerveau et de la Moelle épinière Examiner Dr. Lucie CHARLES University College London Examiner Prof. Stanislas DEHAENE Neurospin Examiner Dr. Sébastien MARTI Neurospin Examiner Prof. Claire SERGENT Paris Descartes Examiner Prof. Catherine TALLON-BAUDRY Ecole Normale Supérieure Examiner [This page is intentionally left blank] 2 An die, die zählen: Mama, Papa, Janka und Henrik 3 [This page is intentionally left blank] 4 Table of contents. TABLE OF CONTENTS ACKNOWLEDGEMENTS ...................................................................................................................... 8 ABSTRACT .......................................................................................................................................... 11 RESUME ............................................................................................................................................. 12 LIST OF FIGURES ................................................................................................................................. 13 LIST OF TABLES ................................................................................................................................... 15 PUBLICATIONS OF THE AUTHOR ......................................................................................................... 16 CHAPTER 1 – GENERAL OVERVIEW OF THE LITERATURE ..................................................................... 17 1.1 Trapped in the moment: The curious case of Henry Gustav Molaison ......................................... 17 1.2 Working memory – connecting the present to the future ............................................................ 18 1.2.1 Delineating short-term memory from long-term memory ................................................... 19 1.2.2 Delineating short-term memory from sensory memory ...................................................... 20 1.2.3 Cognitive models of working memory .................................................................................. 22 1.2.3.1 Systems-based models of working memory ................................................................ 22 1.2.3.2 State-based models of working memory ..................................................................... 24 1.2.4 Searching for the neural correlates of the working memory engram .................................. 25 1.2.4.1 Dedicated or distributed neural system for working memory? ................................... 25 1.2.4.2 Stable, persistent neural activity or dynamic, activity-silent processes as a candidate mechanism for working memory? ................................................................................ 28 1.3 Consciousness – our subjective experience of the here and now ................................................. 32 1.3.1 A scientific approach to the study of consciousness ............................................................ 32 1.3.1.1 A brief history of consciousness science ...................................................................... 32 1.3.1.2 What is consciousness? ................................................................................................ 33 1.3.1.3 How do we manipulate consciousness? ....................................................................... 33 1.3.1.4 How do we measure consciousness? ........................................................................... 35 1.3.2 From cognitive to neurobiological models of conscious access ........................................... 36 1.3.2.1 Cognitive models of attention and working memory as precursors for theories of consciousness................................................................................................................ 37 1.3.2.2 Brief overview over contemporary cognitive models of consciousness ...................... 37 1.3.2.3 Searching for the neural correlates of subjective, conscious experience .................... 38 1.3.3 The depth of non-conscious processing................................................................................ 42 1.4 Putting it all together: Out of sight, out of mind? ......................................................................... 44 1.4.1 Traditional theoretical perspectives support intimate relationship between conscious perception and working memory .......................................................................................... 44 1.4.2 Conscious perception and working memory share common characteristics and brain mechanisms ........................................................................................................................... 46 1.4.2.1 Access to working memory and consciousness guarantees longevity, stability, and robustness of representations ...................................................................................... 46 1.4.2.2 Both working memory and consciousness are capacity-limited, central systems ....... 49 1.4.2.3 Contents of working memory and consciousness may be manipulated and reported 51 1.4.2.4 Similar brain mechanisms appear to subtend working memory and conscious perception ..................................................................................................................... 52 1.4.3 Putting prevailing views to the test: May there be non-conscious working memory as well? ...................................................................................................................................... 54 1.4.3.1 Visual working memory may operate outside the realms of conscious awareness .... 54 1.4.3.2 Visual working memory may operate on non-conscious input .................................... 55 1.5 Outstanding questions ................................................................................................................... 57 CHAPTER 2 – A THEORY OF WORKING MEMORY WITHOUT CONSCIOUSNESS OR SUSTAINED ACTIVITY ........................................................................................................................ 59 2.1 Abstract ......................................................................................................................................... 59 5 Table of contents. 2.2 Introduction ................................................................................................................................... 59 2.3 Results ........................................................................................................................................... 60 2.3.1 Behavioral maintenance and shielding against distraction .................................................. 61 2.3.2 Resistance to conscious working memory load and delay duration ..................................... 62 2.3.3 Similarity of conscious perception and conscious working memory .................................... 63 2.3.4 A sustained decrease in alpha/beta power distinguishes conscious working memory ........ 65 2.3.5 A distinct neurophysiological mechanism for non-conscious working memory................... 66 2.3.6 Contents of conscious and non-conscious working memory can be tracked transiently ..... 67 2.3.7 Further evidence against the conscious maintenance hypothesis ....................................... 69 2.3.8 Short-term synaptic change as a neurophysiological mechanism for conscious and non- conscious working memory ................................................................................................... 71 2.4 Discussion ...................................................................................................................................... 73 2.4.1 Shared brain signatures underlie conscious perception and conscious working memory ... 73 2.4.2 Long-lasting blindsight effect reflects genuine non-conscious working memory ................. 74 2.4.3 A theoretical framework for ‘activity-silent’ working memory ...........................................
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