ISSN 0439-755X
CN 11-1911/B

Acta Psychologica Sinica ›› 2021, Vol. 53 ›› Issue (2): 128-138.doi: 10.3724/SP.J.1041.2021.00128

• Reports of Empirical Studies • Previous Articles     Next Articles

Changes in the level of conflict trigger conflict adaptation

ZHANG Mengke, LI Qing, YIN Shouhang, CHEN Antao()   

  1. Key Laboratory of Cognition and Personality of Ministry of Education, Faculty of Psychology, Southwest University, Chongqing 400715, China
  • Received:2020-02-24 Published:2021-02-25 Online:2020-12-29
  • Contact: CHEN Antao
  • Supported by:
    National Natural Science Foundation of China(31771254);Fundamental Research Funds for the Central University(SWU1609106);Fundamental Research Funds for the Central University(SWU1709107);Fundamental Research Funds for the Central University(SWU1909567)


Conflict adaptation is an important phenomenon, as the interference effect on the current trials is reduced following incongruent versus congruent trials. Moreover, conflict adaptation effect (CAE) is thought to measure adaptive control on a trial-by-trial basis. There are two main theories explaining the mechanisms underlying CAE: conflict monitoring theory and adaptation by binding theory. However, both theories have not explicitly proposed a clear relationship between conflict strength and cognitive control adjustment. Previous studies have mostly focused on the type of conflict that triggers CAE, which reflected qualitative analysis. Hence, it remains unclear whether changes in the level of conflict of the same conflict type affect conflict adaptation.

To address the above issue, the present study recruited 31 healthy participants with a mean age of 19.74 years to perform the variant of the letter flanker task without feature repetitions. Each stimulus was composed of “F/H/N/P” letter components and arranged in a way that a central target letter was flanked by symmetric arrays of two distracter letters. Experiment manipulated the level of conflict by parametrically varying the target-distracter compatibility. Flankers were 100% compatible with the central target for no-conflict condition (e.g., NNNNN), 50% for low-conflict condition (e.g., HNNNH), and 0% for high-conflict condition (e.g., HHNHH). Congruent stimuli were presented on 50% of trials with each incongruent condition occurring equally often on the remaining 50% of trials.

Results showed that reaction times (RTs) increased with the number of incompatible flankers, suggesting a correlation with the level of conflict. Moreover, the interaction between previous trial congruency (no-conflict/low-conflict/high-conflict) and current trial congruency (no-conflict/low-conflict/high-conflict) was significant, which suggested that congruency of previous trials affected the interference effect of current trials. Follow-up analyses revealed that there were classic conflict adaptation phenomena between no-conflict and low-conflict, no-conflict and high-conflict, and low-conflict and high-conflict conditions. These results showed that conflict adaptation was also triggered by the level of conflict in addition to the occurrence of the conflict. Overall, the present study demonstrated that the conflict strength of previous trials was related to the cognitive control level of current trials, showing that larger conflict led to stronger cognitive control adjustment. In addition, the function of conflict-induced cognitive control may be realized by attentional focusing.

In conclusion, the present study emphasizes that changes in the level of conflict could trigger conflict adaptation, which provides more direct support for attention adjustment mechanism of conflict monitoring theory. Combining the existing researches, we infer that conflict monitoring is sensitive to the type and level of conflict, and adjusts the level of cognitive control to facilitate conflict resolution.

Key words: cognitive control, level of conflict, conflict adaptation, attentional focusing