State-trace analysis of associative recognition: comparing single-process and dual-process models.

The aim of this thesis is to investigate competing explanations of the processes underlying associative recognition. Like recognition memory for individual items, associative recognition is currently understood through two different classes of model. The first is the single-process model class which holds that associative recognition decisions are based on a continuum of associative memory strength. The second is the dual-process model class, which holds that associative recognition decisions are based on two sources of information, called familiarity and recollection. Familiarity is conceptualised as a fast-acting, context-free „feeling of knowing‟, while recollection is said to be a slower, more conscious process allowing for the recall of detail and context. Familiarity may play a role in associative recognition through a mechanism called unitisation, whereby two distinct stimuli are bound into a single individual memory trace. State-trace analysis is a method to determine the number of latent variables or processes that contribute to performance on a set of tasks, under mild assumptions. A critical diagnostic feature is the dimensionality of the state-trace plot – a plot of performance on one dependent variable against the other. If associative recognition depends on a single latent variable then manipulation of experimental factors affecting memory should result in a unidimensional state-trace plot. If associative recognition depends on two or more latent variables which are differentially affected by the experimental factors then a bidimensional state-trace will result. State-trace analysis therefore provides a method of discriminating a class of single-process models from a class of dual-process models. State-trace analysis was applied to associative recognition in four experiments. Each experiment utilised two independent variables that previous research had suggested could differentially affect familiarity and recollection. Experiment 1 investigated associative recognition of word pairs by manipulating attention and study presentation frequency. Experiments 2 investigated associative recognition of word pairs under conditions designed to encourage unitisation by pairing an encoding-based unitisation manipulation with a working memory load manipulation. Experiment 3 manipulated the same unitisation instructions as well as varying study time. Experiment 4 examined the effect of unitisation using pairs of faces and manipulated visual similarity and study time. State-trace analysis of the four experiments consistently revealed unidimensional state-trace plots. Using a recently developed monotonic regression statistical test, unidimensionality could not be rejected at either aggregate or individual participant level. Therefore, no evidence was found for the differential activation of familiarity and recollection in associative recognition. The results of this thesis are therefore consistent with a single-process account of associative recognition. These results also pose a challenge to dual-process models to identify alternate experimental manipulations that reveal the involvement of different component processes such as recollection and unitized familiarity.Thesis (Ph.D.) -- University of Adelaide, School of Psychology, 201