The Parallel Episodic Processing (PEP) model 2.0: A single computational model of stimulus-response binding, contingency learning, power curves, and mixing costs

Abstract

The current paper presents an extension of the Parallel Episodic Processing model.The model is developed for simulating behaviour in performance (i.e., speeded response time) tasks and learns to anticipate both how and when to respond based on retrieval of memories of previous trials. With one fixed parameter set, the model is shown to successfully simulate a wide range of different findings. These include: practice curves in the Stroop paradigm, contingency learning effects, learning acquisition curves, stimulus-response binding effects, mixing costs, and various findings from the attentional control domain. The results demonstrate several important points. First, the same retrieval mechanism parsimoniously explains stimulus-response binding, contingency learning, and practice effects. Second, as performance improves with practice, any effects will shrink with it. Third, a model of simple learning processes is sufficient to explain phenomena that are typically (but perhaps incorrectly) interpreted in terms of higher-order control processes. More generally, we argue that computational models with a fixed parameter set and wider breadth should be preferred over those that are restricted to a narrow set of phenomena.

Category learning in the color-word contingency learning paradigm

“…This latter observation seems rather incompatible with the idea that binding effects result from temporary links between stimuli and responses formed in a short-term memory store, whereas contingency learning effects result from encoded regularities in a longer-term store (e.g., Colzato, Raffone, & Hommel, 2006). Instead, this similarity points to the viability of our proposal that binding and contingency learning effects result from the exact same memory processes (Schmidt & De Houwer, 2016a;Schmidt et al, 2016), namely episodic storage and retrieval (Logan, 1988).…”

“…Similar results have been observed with other changes in stimulus features (Allenmark, Moutsopoulou, & Waszak, 2015;Biederman & Cooper, 1991;Biederman & Gerhardstein, 1993). Given our recent proposal that binding effects likely result from the same memory processes that produce contingency learning (Schmidt & De Houwer, 2016a;Schmidt, De Houwer, & Rothermund, 2016), we expected the colour-word contingency effect based on abstract-level categories to occur as readily as the category-based binding effects just outlined. Accordingly, we expected responding to become faster and more accurate to high contingency trials where an item of a category (e.g., professions) is presented in the expected color (e.g., "lawyer" in grey), relative to low contingency trials where an item of the same category is presented in the unexpected color (e.g., "doctor" in orange).…”

“…Indeed, using the one memory retrieval mechanism, the Parallel Episodic Processing (PEP) model (Schmidt et al, 2016) was able to simulate performance (i.e., response times and errors) as typically observed in these distinct speeded-response paradigms (see also, Schmidt, in press).…”

Time course of colour-word contingency learning: Practice curves, pre-exposure benefits, unlearning, and relearning

“…Due to the contingency, most of these will point to a purple response. A computational model of this sort of learning, the Parallel Episodic Processing (PEP) model, has already been demonstrated to produce such contingency learning effects (Schmidt, 2013a;see also, Schmidt, 2013bsee also, Schmidt, , 2016Schmidt & Weissman, 2016) and a forthcoming paper successfully models the acquisition curves PRACTICE AND CONTINGENCY LEARNING 26 observed in the current report (Schmidt, De Houwer, & Rothermund, 2016).…”

Powerful Instructions: Automaticity Without Practice

“…One possibility is the automatic retrieval of episodic representations from memory (e.g., Hintzman, 1988;Logan, 1988;Schmidt, De Houwer, & Rothermund, 2016). For instance, when instructed 'X'left, an episodic trace of this event might be stored in memory.…”