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Both active response execution and passive listening to verbal codes (a form of instruction) in single prime trials lead tovitem-specific repetition priming effects when stimuli re-occur in single probe trials. This holds for task-specific classification (stimulus–classification, SC priming, e.g., apple–small) and action (stimulus–action, SA priming, e.g., apple–right key press). To address the influence of expectation on item-specific SC and SA associations, we tested if item-specific SC and SA priming effects were modulated by the instructed probability of re-encountering individual SC or SA mappings (25% vs. 75% instructed switch probability). Importantly, the experienced item-specific switch probability was always 50%. In Experiment 1 (N = 78), item-specific SA/SC switch expectations affected SA, but not SC priming effects exclusively following active response execution. Experiment 2 (N = 40) was designed to emphasize SA priming by only including item-specific SC repetitions. This yielded stronger SA priming for 25% vs. 75% expected switch probability, both following response execution as in Experiment 1 and also following verbally coded SA associations. Together, these results suggest that SA priming effects, that is, the encoding and retrieval of SA associations, is modulated by item-specific switch expectation. Importantly, this expectation effect cannot be explained by item-specific associative learning mechanisms, as stimuli were primed and probed only once and participants experienced item-specific repetitions/switches equally often across stimuli independent of instructed switch probabilities. This corroborates and extends previous results by showing that SA priming effects are modulated by expectation not only based on experienced item-specific switch probabilities, but also on mere instruction.

In the masked priming paradigm, responses to a target are faster if the prime and target are identical (repetition priming). Forster (submitted) provides evidence that repetition priming consists of a semantic component, due to the shared meaning of the prime and target, and an orthographic component, due to the shared letters. When an unmasked unrelated word intervenes between the prime and target, repetition priming was reduced, but orthographic priming was unaffected. When this intervener was masked, repetition priming was reduced whereas orthographic priming was eliminated. The unmasked intervener may block a semantic component of priming, and a masked intervener blocks the orthographic component. Experiment 1 replicated Forster’s results and confirmed the results were not due to an SOA confound. Experiment 2 included semantically-related primes in an attempt to examine the intervener’s effect on semantic priming, however, our materials did not yield semantic priming even when no intervener was present.

In the masked priming paradigm, responses to a target are faster if the prime and target are identical (repetition priming). Forster (submitted) provides evidence that repetition priming consists of a semantic component, due to the shared meaning of the prime and target, and an orthographic component, due to the shared letters. When an unmasked unrelated word intervenes between the prime and target, repetition priming was reduced, but orthographic priming was unaffected. When this intervener was masked, repetition priming was reduced whereas orthographic priming was eliminated. The unmasked intervener may block a semantic component of priming, and a masked intervener blocks the orthographic component. Experiment 1 replicated Forster’s results and confirmed the results were not due to an SOA confound. Experiment 2 included semantically-related primes in an attempt to examine the intervener’s effect on semantic priming, however, our materials did not yield semantic priming even when no intervener was present.

A warning signal that precedes an imperative stimulus by a certain length of time (the foreperiod) can accelerate responses (foreperiod effect). Plotting reaction time (RT) as a function of foreperiod results in a “U”-shape curve when the foreperiod is fixed in a trial block but manipulated across blocks. When the foreperiod is varied within a block, the foreperiod-RT function is usually negative, with the foreperiod effect modulated by both the current foreperiod and the foreperiod in the prior trial (sequential foreperiod effect). This sequential effect was found to be robust at the shorter foreperiod while diminished at the longer foreperiod. Capizzi et al. (2015) used a non-aging foreperiod distribution and found an increasing foreperiod-RT function (consistent with that in a fixed-foreperiod paradigm) and a sequential effect equal for different foreperiods. They thus proposed a repetition priming account for the sequential foreperiod effect. I conducted three experiments, aiming to test this repetition priming account and to rebuild the connection between the fixed- and variable-foreperiod paradigms. Experiment 1 attempted to replicate Capizzi et al. in a choice-reaction task scenario and found an increasing foreperiod-RT function but a larger sequential effect at the shorter foreperiod. Experiment 2 examined the priming account in a short-foreperiod context and found a decreasing foreperiod-RT function with a larger sequential effect at the shorter foreperiod. Experiment 3 detected a larger sequential effect in general by increasing the difference in duration between the foreperiods that were used in Experiment 2. The current study provided converging evidence that with a non-aging foreperiod distribution the foreperiod-RT function in a variable-foreperiod paradigm shares the same direction as that in a fixed-foreperiod paradigm. However, instead of following Capizzi et al.’s account, the size of the sequential foreperiod effect in general was found to be modulated by the difference in duration between the foreperiods while the relative sizes were determined by the proportions of different foreperiods.

Over the last 30 or more years evidence has accumulated in favour of the view that memory is not a unitary faculty; rather, it can be subdivided into a num- ber of functionally independent subsystems. Whilst dividing memory phenomena into these distinct subsystems has undoubtedly advanced our understanding of memory as a whole, the approach of studying subsystems in isolation fails to address potential interactions between them. Over the last few decades there has been a gradual increase in the number of studies attempting to move be- yond dissociation by characterising functional interactions between subsystems of memory. The main aim of this thesis was to contribute to this endeavour, by examining interactions between two specific subsystems that are positioned on opposite sides of the declarative and non-declarative divide in long-term mem- ory: priming and episodic recognition. Event-Related Potentials (ERPs) were employed to monitor neural markers of repetition priming and episodic memory during recognition tests with masked priming of test cues. In the standard pro- cedure, half of the studied and unstudied test trials began with a brief (48ms) masked repetition of the to-be-recognized word prior to the onset of test items; the remaining unprimed trials were preceded by the word “blank”. The pattern of priming effects across experiments was reasonably consistent, with differences between experiments directly related to the intended manipulations. In contrast to priming effects, the pattern of memory effects was variable across experiments, demonstrating that the engagement of explicit recognition signals is influenced by the outcome of implicit processing, and suggesting that interactions between priming and explicit retrieval processes do occur. Taken together, results from experiments reported in this thesis indicate (1) that under certain circumstances, priming is sufficient to support accurate recognition and does not necessitate changes in memory performance, (2) that mid-frontal old/new effects indexing familiarity are not merely driven by repeated access to semantic information, and (3) that priming influences neural correlates of recollection by speeding their onset. Overall, the data clearly demonstrate that there are multiple potentially interacting routes to recognition.