Electrophysiological Investigations of Recognition Memory: the Role of Pre-Existing Representations in Recollection

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Electrophysiological Investigations of Recognition Memory: the Role of Pre-Existing Representations in Recollection Electrophysiological investigations of recognition memory: The role of pre-existing representations in recollection Graham MacKenzie University of Stirling Submitted as a requirement for the degree of PhD October 2007 Declaration This thesis is submitted in fulfilment of the requirements for the degree of Doctor of Philosophy at the University of Stirling, United Kingdom. I declare that this thesis is based on my original work except quotations and citations which have been duly acknowledged. I also declare that this thesis has not been previously or concurrently submitted, either in whole or in part, for any other qualification at the University of Stirling or other institutions. i Publications The following journal articles have been adapted from experimental work detailed in this thesis: MacKenzie, G. & Donaldson, D.I. (2007). Dissociating recollection from familiarity: Electrophysiological evidence that familiarity for faces is associated with a posterior old/new effect. NeuroImage, 36, 454 - 463. MacKenzie, G. & Donaldson, D.I. (submitted). Is recollection material specific? Faces and names elicit topographically dissociable ERP old/new effects. The following conference presentations have been adapted from experimental work detailed in this thesis: MacKenzie, G. & Donaldson, D.I. (2006). Electrophysiological evidence that a centro-parietal old/new effect is elicited when a face looks familiar but you cannot remember its name. Poster presented at the Cognitive Neuroscience Society Meeting, San Francisco, USA. MacKenzie, G. & Donaldson, D.I. (2007). Electrophysiological evidence that the neural correlates of recollection elicited by face and name retrieval cues are qualitatively distinct. Poster presented at the Cognitive Neuroscience Society Meeting, New York City, USA. MacKenzie, G. & Donaldson, D.I. (2007). Do different retrieval processes support recognition of average and distinctive faces? Evidence from the Remember/Know procedure and Event-Related brain Potentials. Poster presented at the joint Experimental Psychology Society/Psychonomic Society meeting, Edinburgh, UK. ii Acknowledgements This thesis is dedicated to Nina MacKenzie for her support and inspiration. I am indebted to past and present members of the Psychological Imaging Laboratory, University of Stirling. In particular, I would like to thank Professor David Donaldson for setting the cog-wheels of my mind in motion. Thanks are due to Dr Ian Penton-Voak, Josephine Ross and Alana Davis for helping me to create stimuli. Thanks also to Stephen Stewart, Shona MacLean, Catriona Bruce, Bob Lavery and Bruce Sutherland for technical support. Finally, I would like to take this opportunity to thank all the participants who volunteered to take part in experiments. I am indebted to them for their time and effort; this research project would not have been possible without them. iii “If any one faculty of our nature may be called more wonderful than the rest, I do think it is memory. There seems something more speakingly incomprehensible in the powers, the failures, the inequalities of memory, than in any other of our intelligences. The memory is sometimes so retentive, so serviceable, so obedient; at others, so bewildered and so weak; and at others again, so tyrannic, so beyond control! We are, to be sure, a miracle every way; but our powers of recollecting and of forgetting do seem peculiarly past finding out.” Jane Austen, Mansfield Park. iv Abstract Dual-process models of recognition memory propose that recognition memory can be supported by either a general sense of familiarity or the recollection of the encoding context. One source of evidence supporting dual-process models comes from event-related potential (ERP) studies of recognition memory, which have identified distinct patterns of neural activity associated with familiarity and recollection (the mid frontal and left parietal old/new effects, respectively). In this thesis, dual-process accounts of recognition memory were investigated in a series of ERP studies using three categories of stimulus: previously unknown faces, famous faces, and names. For previously unknown faces, familiarity was associated with activity over posterior scalp electrodes while recollection was associated with topographically dissociable activity over anterior electrodes. These dissociable patterns of activity support dual-process models. However, the typical pattern of old/new effects was only observed for stimuli associated with pre-existing representations (i.e., names and famous faces), suggesting that the presence/absence of pre-existing representations may determine the particular retrieval processes that support recognition memory. Furthermore, recollection was associated with two different patterns of activity (anterior and left parietal effects), suggesting that recollection is not a homogenous process. Dual-process theories may represent an important starting point for investigating recognition memory, but neither familiarity nor recollection appear to be functionally homogenous processes when theorizing is constrained by the analysis of scalp recorded electrophysiological activity. v Table of Contents Declaration ..............................................................................................................i Publications............................................................................................................ii Acknowledgements................................................................................................iii Abstract .................................................................................................................. v Table of Contents................................................................................................... vi List of Figures .....................................................................................................viii Chapter 1 – Recognition Memory ........................................................................... 1 Studying memory................................................................................................ 2 Fractionating memory......................................................................................... 3 Episodic retrieval................................................................................................ 9 Dual-process models......................................................................................... 14 Face recognition ............................................................................................... 23 Process purity ................................................................................................... 25 Conclusion........................................................................................................ 27 Chapter 2 – Event-Related Potentials.................................................................... 28 Electrogenesis................................................................................................... 30 Volume conduction........................................................................................... 33 Recording the signal ......................................................................................... 34 Extracting the signal from the noise .................................................................. 37 Drawing inferences from ERPs......................................................................... 41 Chapter 3 – ERPs and Recognition Memory ......................................................... 45 The ERP old/new effect .................................................................................... 46 The neural correlate of recollection................................................................... 48 The neural correlate of familiarity..................................................................... 51 Chapter 4 – General Methods................................................................................ 67 Experimental procedures................................................................................... 67 ERP data acquisition......................................................................................... 72 Data analysis..................................................................................................... 75 Chapter 5 – ERP 1: Name/Other Specifics/No Specifics ....................................... 80 Introduction ...................................................................................................... 80 Method ............................................................................................................. 84 Behavioural Results .......................................................................................... 86 ERP Results...................................................................................................... 87 Discussion ........................................................................................................ 96 vi Chapter 6 – ERP 2: Manipulating Face Familiarity ............................................. 106 Introduction .................................................................................................... 106 Pilot Experiment............................................................................................. 108 Method ........................................................................................................... 112 Behavioural Results .......................................................................................
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