abstract Peter Wühr

Peter Wühr (Institut für Psychologie, Technische Universität Dortmund)

(When) Do global control settings generalize across tasks?

The frequency of stimulus and / or response conflict in a situation or task strongly affects human behavior. For example, in tasks where relevant and irrelevant stimuli are either congruent or incongruent, the impact of irrelevant information on performance (i.e. the congruency effect) is typically smaller in mostly incongruent blocks compared to mostly congruent blocks. The impact of conflict frequency on congruency effects is called the proportion-congruency effect (PCE). There are frequency- and control-based explanations for the PCE. Frequency-based explanations (e.g., differential practice, contingency learning) attribute the PCE to different amounts of practice with congruent and incongruent trials in mostly-congruent versus mostly-incongruent task contexts. Control-based accounts attribute the PCE to adjustments of attentional control settings to each conflict trial (local control), or to more sustained adjustments of attentional control settings to the frequency of conflicting trials (global control). Three pairs of experiments tested whether the PCE generalizes across different S-R dimensions or tasks. The main result was that, in each experiment, the PCE generalized from the manipulated dimension or task to the non-manipulated dimension or task. Frequency-based explanations cannot explain the observed transfer of the PCE, that is, the occurrence of the PCE in a task that contains equal numbers of congruent and incongruent trials. However, the observed transfer of the PCE is consistent with the notion of global control. According to this hypothesis, participants adjust global attentional control settings to conflict frequency in the inducer task, and these control settings then also affect processing in the task with equal numbers of congruent and incongruent trials.