A chain-retrieval model for voluntary task switching

Department of Experimental Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Gent, Belgium.
Cognitive Psychology (Impact Factor: 5.06). 05/2012; 65(2):241-83. DOI: 10.1016/j.cogpsych.2012.04.003
Source: PubMed


To account for the findings obtained in voluntary task switching, this article describes and tests the chain-retrieval model. This model postulates that voluntary task selection involves retrieval of task information from long-term memory, which is then used to guide task selection and task execution. The model assumes that the retrieved information consists of acquired sequences (or chains) of tasks, that selection may be biased towards chains containing more task repetitions and that bottom-up triggered repetitions may overrule the intended task. To test this model, four experiments are reported. In Studies 1 and 2, sequences of task choices and the corresponding transition sequences (task repetitions or switches) were analyzed with the help of dependency statistics. The free parameters of the chain-retrieval model were estimated on the observed task sequences and these estimates were used to predict autocorrelations of tasks and transitions. In Studies 3 and 4, sequences of hand choices and their transitions were analyzed similarly. In all studies, the chain-retrieval model yielded better fits and predictions than statistical models of event choice. In applications to voluntary task switching (Studies 1 and 2), all three parameters of the model were needed to account for the data. When no task switching was required (Studies 3 and 4), the chain-retrieval model could account for the data with one or two parameters clamped to a neutral value. Implications for our understanding of voluntary task selection and broader theoretical implications are discussed.

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Available from: André Vandierendonck
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    • "An important part of research in recent years has indeed been concerned with aspects of self-control, volition, and the like. As shown by some studies on task switching, the WM system may provide an excellent substrate for self-control in the form of the phonological loop (Goschke, 2000; Baddeley et al., 2001; Emerson and Miyake, 2003; Miyake et al., 2004; Bryck and Mayr, 2005; Demanet et al., 2010; Vandierendonck et al., 2012). That there are links between executive control and self-control is beyond doubt, but should be the subject of a separate study. "
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    • "Converging evidence for such an interpretation of our results comes from voluntary task switching experiments, where subjects seem to choose sequences of actions, not individual actions in each trial (Vandierendonck et al. 2012). According to Holroyd and Yeung, the specific function of the ACC then is to select which of the available choice sequences to implement. "
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    • "On explicit trials, this mental model is not required, as the only current goal is to perform the instructed task. A recent model of task choice in the VTS paradigm suggests that participants generate short sequences which are maintained in working memory to guide task selection (Vandierendonck et al., 2012). Given that across a variety of tasks the LFP co-activates with the fronto-parietal control network and the other regions of the cingulo-opercular network (Gilbert et al., 2010), the LFP is in a position to represent overall task goals that can then be implemented by the more posterior control regions of the frontoparietal control network and the cinguloopercular network. "
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