People are able to respond more quickly to stimuli following a recent encounter with those same items. This facilitation in processing a stimulus as a function of a prior encounter is known as repetition priming. This thesis contains eleven experiments that attempt to describe the nature of the representations in memory underlying the effect. Changing aspects of the stimuli and task between the initial encounter and the subsequent test encounter allow examination of the kinds of information contained in these representations. The effects on repetition priming of recombining the pairings of simultaneously presented items in a speeded same/different matching task were examined (Experiments 1,2, 3 & 6). Despite priming being insensitive to the pairings of items, subjects were able to recognise this information (Experiment 4), revealing an item-specific locus for the priming effect and a dissociation from explicit memory. Priming was shown to be based on domain- specific and not conceptual information (Experiment 5). Experiments 7 and 8 examined the role of repeating the decision and response to stimuli in producing repetition priming. Results suggested that any such role reflects subjects' use of explicit memory as a basis for responding in the task, rather than reflecting automatic priming effects. Manipulating the semantic interpretation demanded of a homograph between training and test did not affect repetition priming (Experiment 9). The independent representation of simultaneously presented stimuli did not necessarily depend upon the activation of pre-existing representations or connections (Experiment 10). Experiment 11 revealed a necessary role for the identification of stimuli in producing repetition priming. The results of these eleven experiments pose problems for accounts of repetition priming based on the retrieval of processing episodes, or the reinstatement of processing demands. The results are consistent with a perceptual locus of the priming effect, based on representations of structure and form employed in the identification of individual stimuli.

No description available.

Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Psychology." Includes bibliographical references (p. 47-50).

Thesis (Ph. D.)--University of California, San Diego, 1997. / Vita. Includes bibliographical references (leaves 127-133).

Many items encoded into episodic memory are highly similar – seeing a stranger’s car may result in a memory representation which overlaps in many features with the memory of your friend’s car. To avoid falsely recognising the novel but similar car, it is important for the representations to be distinguished in memory. Even in healthy young adults failures of this mnemonic discrimination lead relatively often to false recognition, and such errors become substantially more frequent in older age. Whether an item’s representation is discriminated from similar memory representations depends critically on how it is encoded. However, the precise encoding mechanisms involved remain poorly understood. Establishing the determinants of successful mnemonic discrimination is essential for future research into strategies or interventions to prevent recognition errors, particularly in the context of age-related decline. A fuller understanding of age-related decline in mnemonic discrimination can also inform basic models of memory. This thesis evaluated the contribution of encoding processes to mnemonic discrimination both in young adults and in ageing, within the framework of two prominent accounts of recognition memory, the pattern separation account (Wilson et al., 2006) and Fuzzy Trace Theory (FTT; Brainerd & Reyna, 2002). Firstly, a functional magnetic resonance imaging study in young adults found evidence for differences in regions engaged at encoding of images according to the accuracy of later mnemonic discrimination, consistent with both pattern separation and FTT. Evidence of functional overlap between regions showing activity consistent with pattern separation, and activity associated with later accurate recognition was consistent with a role of cortical pattern separation in successful encoding, but there was no direct evidence that cortical pattern separation contributed to mnemonic discrimination. This first evidence of cortical pattern separation in humans was supported by findings that in the majority of pattern separation regions, response functions to stimuli varied in their similarity to previous items were consistent with predictions of computational models. Regional variation in the dimension(s) of similarity (conceptual/perceptual) driving pattern separation was indicative of variation in the type of mnemonic interference minimised by cortical pattern separation. Further evidence of encoding contributions to mnemonic discrimination was provided by an event-related potential study in young and older adults. Older adults showed less distinct waveforms than young adults at encoding of items whose similar lures were later correctly rejected compared to those falsely recognised, supporting the proposal that age-related encoding impairments contribute to the decline in mnemonic discrimination. Finally, a set of behavioural studies found that older adults’ mnemonic discrimination deficit is increased by conceptual similarity, supporting previous findings and consistent with FTT’s account of greater emphasis by older adults on gist processing. However, older adults required greater reduction in perceptual or conceptual similarity in order to successfully reject lures, as uniquely predicted by the pattern separation account. Together, the findings support the notion that encoding processes contribute directly to mnemonic discrimination and its age-related decline. An integrated view of the pattern separation account and FTT is discussed and developed in relation to the current findings.

Thesis (M.A.)--University of Nevada, Reno, 2006. / "August, 2006." Includes bibliographical references (leaves 36-37). Online version available on the World Wide Web.

Thesis (Ph. D.)--Johns Hopkins University, 1930. / Vita. Published also as Comparative psychology monographs, v. 7, serial no. 34, February, 1931. Bibliography: p. 81-82.

Issued also as Thesis (Ph. D.)--Columbia University. / Bibliography: p. 55-56.

Thesis (Ph. D.)--Johns Hopkins University, 1930. / Vita. Published also as Comparative psychology monographs, v. 7, serial no. 34, February, 1931. "References": p. 81-82.

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.