Strategic control processes in episodic memory and beyond
Abstract
The evaluation of past experience is influenced both by the strength of retrieved
memories and factors in the immediate retrieval environment, including emphasised
goals and cued expectations. However, the laboratory study of episodic memory has
neglected such environmental influences, despite their overt contribution to real-world decision outcomes. The aim of this PhD thesis was to rectify this neglect, and
clarify the interaction of memory evidence and environmental strategies in the
service of strategic memory control. A related aim was to investigate whether control
processes identified in the isolated domain of episodic memory in fact performed a
more general or “cross-domain” function.
An initial series of behavioural experiments (Experiments 1-3) elucidated an
overlooked source of strategic bias in the standard recognition environment – implicit
goal emphasis imparted by question format. Experiment 4 investigated whether the
question bias was commonly enacted across different domains of evaluation,
yielding modest evidence in favour of this underlying cross-domain function.
Experiment 5 instantiated more explicit manipulation of goal emphasis and cued
expectation, and recovered independent and opposing strategic effects of these two
environmental factors, emerging across episodic and non-episodic domains.
Experiment 6 employed a simultaneous EEG-fMRI approach to elucidate the neural
correlates of memory control, identifying a modulation of the late positive event-related potential during the resolution of mnemonic conflict, which was sourced to
BOLD variation in regions of the rostral cingulate zone and intraparietal sulcus.
Experiment 7 used pupillometry to examine pupil-linked autonomic systems that
have also been implicated in memory control, and isolated two distinct components
of the dilation response evoked during environmental conflict – an “early amplitude”
unexpected familiarity effect and a “trailing slope” uncertainty effect. The findings
illuminate the cross-domain underpinnings of an adaptive memory control system,
evidenced in behaviour and across different functional neuroimaging modalities, and
across episodic and non-episodic domains of evaluation.
Type
Thesis, PhD Doctor of Philosophy
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