Memory activation and the availability of explanations in sequential diagnostic reasoning.

Department of Psychology, University of Groningen, Postbus 72, 9700 AB Groningen, the Netherlands.
Journal of Experimental Psychology Learning Memory and Cognition (Impact Factor: 3.1). 06/2011; 37(6):1391-411. DOI: 10.1037/a0023920
Source: PubMed

ABSTRACT In the field of diagnostic reasoning, it has been argued that memory activation can provide the reasoner with a subset of possible explanations from memory that are highly adaptive for the task at hand. However, few studies have experimentally tested this assumption. Even less empirical and theoretical work has investigated how newly incoming observations affect the availability of explanations in memory over time. In this article we present the results of 2 experiments in which we address these questions. While participants diagnosed sequentially presented medical symptoms, the availability of potential explanations in memory was measured with an implicit probe reaction time task. The results of the experiments were used to test 4 quantitative cognitive models. The models share the general assumption that observations can activate and inhibit explanations in memory. They vary with respect to how newly incoming observations affect the availability of explanations over time. The data of both experiments were predicted best by a model in which all observations in working memory have the same potential to activate explanations from long-term memory and in which these observations do not decay. The results illustrate the power of memory activation processes and show where additional deliberate reasoning strategies might come into play.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Sequentially observed symptoms in diagnostic reasoning have to be integrated to arrive at a final diagnosis. In our experiments employing quasi-medical problems, four sequentially presented symptoms were consistent with multiple diagnostic hypotheses. We tested whether symptom order creates biases in symptom evaluation. Early symptoms induced a bias towards the initial hypothesis even though an alternative hypothesis was equally supported. In two experiments, stepwise ratings were prompted to explicitly highlight alternative hypotheses. Explicit highlighting eliminated the bias towards the initial hypothesis if only two hypotheses competed, but the bias remained if more than two hypotheses were associated with symptoms in a sequence. Our results are consistent with process models of information integration that specify how early information can frame the processing of later information. Extending previous results obtained with fewer contending hypotheses, we show limits in impartially considering more than two hypotheses.
    34th Annual Conference of the Cognitive Science Society 2012, Sapporo, Japan; 08/2012
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In diagnostic reasoning, knowledge about symptoms and their likely causes is retrieved to generate and update diagnostic hypotheses in memory. By letting participants learn about causes and symptoms in a spatial array, we could apply eye tracking during diagnostic reasoning to trace the activation level of hypotheses across a sequence of symptoms and to evaluate process models of diagnostic reasoning directly. Gaze allocation on former locations of symptom classes and possible causes reflected the diagnostic value of initial symptoms, the set of contending hypotheses, consistency checking, biased symptom processing in favor of the leading hypothesis, symptom rehearsal, and hypothesis change. Gaze behavior mapped the reasoning process and was not dominated by auditorily presented symptoms. Thus, memory indexing proved applicable for studying reasoning tasks involving linguistic input. Looking at nothing revealed memory activation because of a close link between conceptual and motor representations and was stable even after one week.
    Cognitive Psychology 12/2013; 68C:59-97. · 4.05 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although temporal dynamics are inherent aspects of diagnostic tasks, few studies have investigated how various aspects of time course influence hypothesis generation. An experiment is reported that demonstrates that working memory dynamics operating during serial data acquisition bias hypothesis generation. The presentation rate (and order) of a sequence of serially presented symptoms was manipulated to be either fast (180 ms per symptom) or slow (1,500 ms per symptom) in a simulated medical diagnosis task. When the presentation rate was slow, participants chose the disease hypothesis consistent with the symptoms appearing later in the sequence. When the presentation rate was fast, however, participants chose the disease hypothesis consistent with the symptoms appearing earlier in the sequence, therefore representing a novel primacy effect. We predicted and account for this effect through competitive working memory dynamics governing information acquisition and the contribution of maintained information to the retrieval of hypotheses from long-term memory.
    Psychonomic Bulletin & Review 09/2012; · 2.99 Impact Factor

Full-text (2 Sources)

Available from
Jun 4, 2014