scholarly journals The Stroop Effect From a Mixture of Reading Processes: A Fixed-Point Analysis

Author(s):  
Gabriel Tillman

For the last 80 years, the Stroop task has been used to test theories of attention and cognitive control and it has been applied in many clinical settings. Most theories posit that the overwhelming power of written words overcomes strict instructions to focus on print color and ignore the word. Recent evidence suggests that trials in the Stroop task could in fact be a mixture of reading trials and non-reading trials. Here we conduct a critical test of this mixture hypothesis, where a mixture of processes should satisfy the xed-point property (Falmagne, 1968).

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Albert Lehr ◽  
Niklas Henneberg ◽  
Tarana Nigam ◽  
Walter Paulus ◽  
Andrea Antal

Behavioral response conflict arises in the color-word Stroop task and triggers the cognitive control network. Midfrontal theta-band oscillations correlate with adaptive control mechanisms during and after conflict resolution. In order to prove causality, in two experiments, we applied transcranial alternating current stimulation (tACS) at 6 Hz to the dorsolateral prefrontal cortex (DLPFC) during Stroop task performance. Sham stimulation served as a control in both experiments; 9.7 Hz tACS served as a nonharmonic alpha band control in the second experiment. We employed generalized linear mixed models for analysis of behavioral data. Accuracy remained unchanged by any type of active stimulation. Over both experiments, the Stroop effect (response time difference between congruent and incongruent trials) was reduced by 6 Hz stimulation as compared to sham, mainly in trials without prior conflict adaptation. Alpha tACS did not modify the Stroop effect. Theta tACS can both reduce the Stroop effect and modulate adaptive mechanisms of the cognitive control network, suggesting midfrontal theta oscillations as causally involved in cognitive control.


2021 ◽  
Author(s):  
Arthur Prével ◽  
Ruth Krebs ◽  
Nanne Kukkonen ◽  
Senne Braem

Motivation signals have been shown to influence the engagement of cognitive control processes. However, most studies focus on the invigorating effect of reward prospect, rather than the reinforcing effect of reward feedback. The present study aimed to test whether people strategically adapt conflict processing when confronted with condition-specific congruency-reward contingencies in a manual Stroop task. Results show that the size of the Stroop effect can be affected by selectively rewarding responses following incongruent versus congruent trials. However, our findings also suggest important boundary conditions. Our first two experiments only show a modulation of the Stroop effect in the first half of the experimental blocks, possibly due to our adaptive threshold procedure demotivating adaptive behavior over time. The third experiment showed an overall modulation of the Stroop effect, but did not find evidence for a similar modulation on test items, leaving open whether this effect generalizes to the congruency conditions, or is stimulus-specific. More generally, our results are consistent with computational models of cognitive control and support contemporary learning perspectives on cognitive control. The findings also offer new guidelines and directions for future investigations on the selective reinforcement of cognitive control processes.


PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0255430
Author(s):  
Arthur Prével ◽  
Ruth M. Krebs ◽  
Nanne Kukkonen ◽  
Senne Braem

Motivation signals have been shown to influence the engagement of cognitive control processes. However, most studies focus on the invigorating effect of reward prospect, rather than the reinforcing effect of reward feedback. The present study aimed to test whether people strategically adapt conflict processing when confronted with condition-specific congruency-reward contingencies in a manual Stroop task. Results show that the size of the Stroop effect can be affected by selectively rewarding responses following incongruent versus congruent trials. However, our findings also suggest important boundary conditions. Our first two experiments only show a modulation of the Stroop effect in the first half of the experimental blocks, possibly due to our adaptive threshold procedure demotivating adaptive behavior over time. The third experiment showed an overall modulation of the Stroop effect, but did not find evidence for a similar modulation on test items, leaving open whether this effect generalizes to the congruency conditions, or is stimulus-specific. More generally, our results are consistent with computational models of cognitive control and support contemporary learning perspectives on cognitive control. The findings also offer new guidelines and directions for future investigations on the selective reinforcement of cognitive control processes.


Author(s):  
Lilach Akiva-Kabiri ◽  
Avishai Henik

The Stroop task has been employed to study automaticity or failures of selective attention for many years. The effect is known to be asymmetrical, with words affecting color naming but not vice versa. In the current work two auditory-visual Stroop-like tasks were devised in order to study the automaticity of pitch processing in both absolute pitch (AP) possessors and musically trained controls without AP (nAP). In the tone naming task, participants were asked to name the auditory tone while ignoring a visual note name. In the note naming task, participants were asked to read a note name while ignoring the auditory tone. The nAP group showed a significant congruency effect only in the tone naming task, whereas AP possessors showed the reverse pattern, with a significant congruency effect only in the note reading task. Thus, AP possessors were unable to ignore the auditory tone when asked to read the note, but were unaffected by the verbal note name when asked to label the auditory tone. The results suggest that pitch identification in participants endowed with AP ability is automatic and impossible to suppress.


Author(s):  
Laurent Grégoire ◽  
Pierre Perruchet ◽  
Bénédicte Poulin-Charronnat

Grégoire, Perruchet, and Poulin-Charronnat (2013) claimed that the Musical Stroop task, which reveals the automaticity of note naming in musician experts, provides a new tool for studying the development of automatisms through extensive training in natural settings. Many of the criticisms presented in the four commentaries published in this issue appear to be based on a misunderstanding of our procedure, or questionable postulates. We maintain that the Musical Stroop Effect offers promising possibilities for further research on automaticity, with the main proviso that the current procedure makes it difficult to tease apart facilitation and interference.


2011 ◽  
Vol 158 (8) ◽  
pp. 1085-1089 ◽  
Author(s):  
M.M. Marsh ◽  
J.R. Prajs

2001 ◽  
Vol 64 (3) ◽  
pp. 435-444 ◽  
Author(s):  
Andrzej Wiśnicki

A Banach space X is said to have property (Sm) if every metrically convex set A ⊂ X which lies on the unit sphere and has diameter not greater than one can be (weakly) separated from zero by a functional. We show that this geometrical condition is closely connected with the fixed point property for nonexpansive mappings in superreflexive spaces.


Sign in / Sign up

Export Citation Format

Share Document