Figure 1.

Architecture of the proactive control/task conflict (PC-TC) model of the Stroop task. From Kalanthroff et al., 2018a, p. 2. Copyright 2018 by American Psychological Association. Reprinted with permission from American Psychological Association. In this model, task control is considered a proactive, effortful process that deploys control in advance of the stimulus for the resolution of conflict (De Pisapia and Braver, 2006; Braver et al., 2007; Barch and Ceaser, 2012; Braver, 2012). Pointy-headed arrows represent excitatory connections, whereas the round-headed arrows represent inhibitory connections. A stimulus activates its color and lexical representations in the input (features) layers. The activations from the input layers propagate to the response layer and to the task demand layer, which feeds back to the input layers. Congruent and incongruent color words, but not (non-word) neutral stimuli, activate both task demand units, which lead to task conflict. This task conflict inhibits the response layer, thereby slowing down responses to color words and resulting in Stroop reverse facilitation effect. When proactive control is high, attention is sufficiently biased in a top-down manner to the color-naming task demand unit, thus preventing (or rapidly resolving) task conflict and resulting in Stroop facilitation effect. However, manipulations that reduce proactive control lead to a stronger capture of attention by the irrelevant task dimension (word meaning), resulting in a reverse facilitation effect. This process takes place in both congruent and incongruent trials. In incongruent trials, an additional information conflict takes place when both input layers provide contradictory information (e.g., blue in the color features and green in the lexical features), leading to the activation of the two (mutually inhibitory) response units in the response layer, which causes the slowing down of reaction time and result in a (robust) Stroop interference effect.