Durham E-Theses Electrophysiological correlates of anticipation and emotional memory TABASSUM, NAZOOL-E How to cite: TABASSUM, NAZOOL-E (2015) Electrophysiological correlates of anticipation and emotional memory, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/11560/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk 2 Nazool -e Tabassum Electrophysiological correlates of anticipation and emotional memory Abstract This thesis investigated the role of anticipation as a mediating factor in the Emotion- Enhanced Memory (EEM) phenomenon. Using behavioural and ERP measures, three anticipatory conditions were explored: Informative, No-Cue and Non-Informative. The primary objective was to determine how far the pre-stimulus-Dm (Ps-Dm) effect is a reliable indicator of emotional memory encoding under different levels of anticipation, and if the preparatory process explanation accounts for any effects. This study also aimed to determine if there is an association between anticipatory activity at the pre- and post- stimulus phase, and the related behavioural outcome. One behavioural and three ERP studies were conducted to measure the difference due to memory (Dm) effect during an anticipatory phase. The Dm effect distinguishes between neural activity of subsequently remembered and forgotten items, providing an index of successful encoding. We employed an S1-S2 (Stimulus 1: Cues - Stimulus 2: Pictures) Cueing-Subsequent Memory Paradigm. Upper case letters (O, X, Z) served as cue stimuli (S1). Emotional and neutral images selected from International Affective Picture System (IAPS) were used as S2. Findings revealed a Dm effect for informative as well as for non-informative cue conditions when participants anticipated high-arousal emotionally negative pictures. This effect was found during the 400-600ms time window only when the cue remained on the screen. This effect was not significant for the studies in which the arousal level of anticipated negative pictures was mixed. Moreover, the behavioral findings mirrored the neural activity in this particular study. However, in rest of the studies, behavioral results could not corroborate neural activity. The results of the present set of experiments highlighted that emotional memory might be formed without specific information about the content or valence of imminent pictures. 1 Electrophysiological correlates of anticipation and emotional memory -------------------------------------------------------------------------- Nazool-e Tabassum Submitted for the degree of Doctor of Philosophy Cognitive Neuroscience Department of Psychology The University of Durham 2015 2 Table of Contents Abstract ......................................................................................................................... 1 List of Figures ................................................................................................................. 9 List of Tables ................................................................................................................ 11 Declarations ................................................................................................................. 12 Statement of Copyright ................................................................................................ 13 Acknowledgments ........................................................................................................ 14 General Introduction ................................................................................... 15 1.1 Brief history of theories of emotion ................................................................................ 15 1.2 Emotion: Appraisal, Valence, and Arousal. ...................................................................... 17 1.3 Memory: Encoding, consolidation, and retrieval. ............................................................ 19 1.4 The subsequent memory paradigm (SMP) ...................................................................... 21 1.4.1 Emotion-Enhanced Memory (EEM): Theoretical framework .......................... 24 1.4.2 Electrophysiological correlates of encoding and anticipation ......................... 26 1.4.3 Elaboration and EEM........................................................................................ 29 1.4.4 Anticipation and EEM....................................................................................... 30 1.5 Behavioural Procedures and EEM .................................................................................... 33 1.5.1 Recall memory ................................................................................................. 33 1.5.2 Recognition memory ........................................................................................ 33 1.6 Gender difference and Pre-stimulus activity ................................................................... 34 1.7 Selection of Event-related potential (ERP) ...................................................................... 35 1.8 Significance of the issues ................................................................................................. 36 1.9 Thesis Objective ............................................................................................................... 36 General Electroencephalography Method .................................................... 37 2.1 Overview .......................................................................................................................... 37 2.2 EEG/ERP background ....................................................................................................... 37 2.3 Spontaneous EEG versus ERP ........................................................................................... 38 2.4 Features and characteristics of ERP ................................................................................. 39 2.4.1 Signal-to-noise ratio ......................................................................................... 39 2.4.2 Components ..................................................................................................... 40 2.4.3 Nomenclature .................................................................................................. 40 2.4.4 Identifying a component .................................................................................. 41 2.4.5 Inferences and ERP data .................................................................................. 43 2.5 ERP: Hardware and software ........................................................................................... 43 2.5.1 Stimulus display ............................................................................................... 43 2.5.2 Data recording and acquisition ........................................................................ 44 3 2.5.3 Amplifiers and Impedance ............................................................................... 45 2.5.4 EEG montage and reference electrode ............................................................ 45 2.6 Data analysis .................................................................................................................... 46 2.6.1 ERP: Pre-processing of data ............................................................................. 46 2.6.2 Filtering ............................................................................................................ 46 2.6.3 Artefact identification and correction ............................................................. 47 2.6.4 Segmentation/epoch ....................................................................................... 48 2.6.5 Baseline removal .............................................................................................. 48 2.6.6 Averaging ......................................................................................................... 48 2.6.7 Re-referencing ................................................................................................. 49 2.6.8 Statistical analysis ............................................................................................ 49 2.7 Graphic representation .................................................................................................... 51 Role of level of processing in modulating emotional memory ....................... 52 3.1 Overview .......................................................................................................................... 52 3.2 General Introduction ........................................................................................................ 52 3.3 Experiment 1: Semantic elaboration versus shallow processing ..................................... 54 3.3.1 Introduction ....................................................................................................