Use this URL to cite or link to this record in EThOS:
Title: Empirical and methodological investigations into novelty and familiarity as separate processes that support recognition memory in rats and humans
Author: Sivakumaran, Magali H.
ISNI:       0000 0004 7234 3424
Awarding Body: University of St Andrews
Current Institution: University of St Andrews
Date of Award: 2018
Availability of Full Text:
Access from EThOS:
Access from Institution:
There is a prevalent assumption in the recognition memory literature that the terms “novelty” and “familiarity” are words ascribed to differing extremities of a single memory strength continuum. The aim of the current thesis was to integrate experimental methodologies across human and rodents to further investigate novelty processing at both a cognitive and neural level, and assess whether it is dissociable from familiarity processing. This dissociation was questioned at a cognitive level in human participants in Experiments 1 to 3 and at a neural level in rats in Experiment 4 and 5. Participants were found to differentially assess novelty and familiarity when making confidence judgements about the mnemonic status of an item (Experiment 1). Additionally, novelty and familiarity processing for questioned items were found to be dissimilarly affected by the presence of a concurrent item of varying mnemonic statuses (Experiment 2 and 3). The presence of a concurrent familiar item did not impact novelty processing in the perirhinal cortex (Experiment 4 and 5), yet disrupted the neural networks established to be differentially engaged by novelty and familiarity (Experiment 5). These findings challenge the assumption that the terms “novelty” and “familiarity” relate to a single recognition memory process. Finally, to allow integration of the findings from the human and rodent experiments, the relationship between measures or recognition memory obtained from spontaneous object recognition (SOR) task in rats and recognition memory measures estimated from signal-detection based models of recognition memory in humans was investigated (Experiment 6 and 7). This revealed that novelty preference in the SOR was positively correlated to measures of recognition memory sensitivity, but not bias. Thus, this thesis argues for the future inclusion of a novelty as a dissociable process from familiarity in our understanding of recognition memory, and for the integrations of experimental methodologies used to test recognition memory across species.
Supervisor: O'Connor, Akira Robert ; Ainge, James Alexander Sponsor: Biotechnology and Biological Sciences Research Council (BBSRC)
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: Familiarity ; Novelty ; Recognition memory ; BF378.R4S5 ; Recognition (Psychology) ; Memory--Physiological aspects ; Rats--Psychology ; Cognitive psychology