Place in other tasks (cf. Kahneman, 2003; Logan, 1979, 1988; Schneider Shiffrin, 1977; Shiffrin Schneider, 1977). Thus, stop processing can occur independently from go processing for most of the time in the consistent-mapping group.Author Manuscript Author Manuscript Author Manuscript Author Manuscript2. ExperimentsIn Experiment 1, the primary go task was a number magnitude task in which subjects had to Pan-RAS-IN-1MedChemExpress Pan-RAS-IN-1 decide whether a digit (the go stimulus) was smaller or larger than 5. On 25 of the trials (signal trials), a colored circle or square (i.e. the change signal; Fig. 2) could appear on the left or right of the digit. When the signal was valid (25 of the signal trials), subjects had to cancel their response to the digit and respond to the location of the signal instead. When the change signal was invalid, subjects had to ignore it and execute the go response as planned. At the beginning of each trial, we presented a word cue to indicate signal validity (e.g. `RED CIRCLE’). Subjects had to stop and change their response when the colored shape (i.e. the signal) matched the word cue. In the consistent-mapping group, the valid signal remained the same throughout the experiment, but in the varied-mapping group, it changed every four trials. Experiment 2 was primarily designed to replicate the findings of Experiment 1 with different signals, different cues, and PD0325901MedChemExpress PD325901 another primary task. The signals were 3 ?3 or 9 ?9 white-andblack chequerboards that could be rotated (square vs. diamond; Fig. 2). We presented a word cue to indicate signal validity at the beginning of each trial (e.g. `3 ?3 diamond’), but we counterbalanced the order of the cued features1 (Fig. 2). In the consistent-mapping group,1Exploratory analyses (not shown) indicated that subjects in both groups of Experiment 1 were more distracted by invalid signals that had the same color as the valid signal (compared with shape overlap or no overlap). This difference between color and shape could have been due to the order of the words in the cue (i.e. color hape), or the relative salience of the features. To rule out the first possibility, we counterbalanced feature order in the cues of Experiment 2.Cognition. Author manuscript; available in PMC 2016 April 08.Verbruggen and LoganPagethe valid signal remained the same throughout the experiment, but in the varied-mapping group, it changed every four trials. In the primary go task, subjects decided whether a letter (a, b, y, or z; the go stimuli) occurred at the beginning or end of the alphabet. We used letters instead of digits to avoid overlap between the go stimulus and the cue. In Experiment 3, we reduced memory demands but increased switch demands. Accuracy on no-signal trials was quite low for some subjects in Experiment 2 (see below), so we simplified the primary go task in Experiment 3: subjects had to decide whether the letter (the go stimulus) was `U’ or `D’. Each trial started with the presentation of a chequerboard (the cue) in the center of the screen. The cue was followed by the go stimulus (i.e. the letter). On signal trials, another chequerboard (the signal) appeared to the left or right of the go stimulus after a variable delay. Subjects were instructed to stop and change their response when the second chequerboard (i.e. the signal) matched the first chequerboard (i.e. the cue); on mismatch trials, subjects had to ignore the signal and execute the go response as planned. We expected that presenting the valid chequerboard.Place in other tasks (cf. Kahneman, 2003; Logan, 1979, 1988; Schneider Shiffrin, 1977; Shiffrin Schneider, 1977). Thus, stop processing can occur independently from go processing for most of the time in the consistent-mapping group.Author Manuscript Author Manuscript Author Manuscript Author Manuscript2. ExperimentsIn Experiment 1, the primary go task was a number magnitude task in which subjects had to decide whether a digit (the go stimulus) was smaller or larger than 5. On 25 of the trials (signal trials), a colored circle or square (i.e. the change signal; Fig. 2) could appear on the left or right of the digit. When the signal was valid (25 of the signal trials), subjects had to cancel their response to the digit and respond to the location of the signal instead. When the change signal was invalid, subjects had to ignore it and execute the go response as planned. At the beginning of each trial, we presented a word cue to indicate signal validity (e.g. `RED CIRCLE’). Subjects had to stop and change their response when the colored shape (i.e. the signal) matched the word cue. In the consistent-mapping group, the valid signal remained the same throughout the experiment, but in the varied-mapping group, it changed every four trials. Experiment 2 was primarily designed to replicate the findings of Experiment 1 with different signals, different cues, and another primary task. The signals were 3 ?3 or 9 ?9 white-andblack chequerboards that could be rotated (square vs. diamond; Fig. 2). We presented a word cue to indicate signal validity at the beginning of each trial (e.g. `3 ?3 diamond’), but we counterbalanced the order of the cued features1 (Fig. 2). In the consistent-mapping group,1Exploratory analyses (not shown) indicated that subjects in both groups of Experiment 1 were more distracted by invalid signals that had the same color as the valid signal (compared with shape overlap or no overlap). This difference between color and shape could have been due to the order of the words in the cue (i.e. color hape), or the relative salience of the features. To rule out the first possibility, we counterbalanced feature order in the cues of Experiment 2.Cognition. Author manuscript; available in PMC 2016 April 08.Verbruggen and LoganPagethe valid signal remained the same throughout the experiment, but in the varied-mapping group, it changed every four trials. In the primary go task, subjects decided whether a letter (a, b, y, or z; the go stimuli) occurred at the beginning or end of the alphabet. We used letters instead of digits to avoid overlap between the go stimulus and the cue. In Experiment 3, we reduced memory demands but increased switch demands. Accuracy on no-signal trials was quite low for some subjects in Experiment 2 (see below), so we simplified the primary go task in Experiment 3: subjects had to decide whether the letter (the go stimulus) was `U’ or `D’. Each trial started with the presentation of a chequerboard (the cue) in the center of the screen. The cue was followed by the go stimulus (i.e. the letter). On signal trials, another chequerboard (the signal) appeared to the left or right of the go stimulus after a variable delay. Subjects were instructed to stop and change their response when the second chequerboard (i.e. the signal) matched the first chequerboard (i.e. the cue); on mismatch trials, subjects had to ignore the signal and execute the go response as planned. We expected that presenting the valid chequerboard.