Recognition-induced updating of face memories: behavioural and electrophysiological evidence

Episodic memories are prone to 'updating', that is, memories can be strengthened or distorted after their initial encoding. The majority of research has examined the cognitive and neurocognitive mechanisms for the updating of elaborate episodic memories, however the goal of this thesis was to examine mechanisms for the updating of simpler episodic memories, such as memories for faces. For all experiments, a novel repeated recognition paradigm required participants to complete two recognition tests, with target faces (shown during a previous learning phase) presented amongst four distractor faces (not seen prior to the first test). Critically, face stimuli were derived from artificial face space models to control perceptual differences between images, as well as to use the Euclidean distance between face images as a continuous metric of recognition (details in Chapter 2). Within Chapter 3, it was found that elevated confidence judgements during initial recognition attempts predicted whether participants would recognise the same face in a subsequent test, regardless of the accuracy of recognition judgements on the initial test. In Chapter 4, it was queried whether face memory updating would be increased after retrieving vs. re-studying face memories. Results showed that retrieval enhanced the updating of face memories compared to re-study tasks, despite these tasks encouraging participants to encode faces that were cued to participants (Experiment 4a & c) or were selected according to distinctiveness (Experiment 4c). Finally, the electrophysiological correlates of face memory retrieval and updating were examined with ERPs (Chapter 5) and oscillations (Chapter 6). ERPs largely corresponded to the retrieval and reactivation of target memories recognised with high confidence. However, oscillatory markers of objective, subjective and updating processes were found. Together, this thesis provides the first evidence of the cognitive and neurocognitive mechanisms underlying the retrieval- induced updating of face memories.