University of Twente Student Theses


Sequential effects in the Simon task: conflict monitoring or memory?

Lanting, I. (2013) Sequential effects in the Simon task: conflict monitoring or memory?

[img] PDF
Abstract:Compatibility tasks (e.g. Simon task and flanker task) provide more information about automatism and attention. In these tasks, incompatible trials are performed slower and less accurate than compatible trials; i.e. the compatibility effect. Compatibility effects are higher after a compatible trial than after an incompatible trial. This is known as the Gratton effect. Until recently it was thought that the conflict monitoring model explained these effects. According to this model conflict arises during an incompatible trial. Conflict has been related to activity in the anterior cingulate cortex and can be detected by measuring the activity of the N2 component. When conflict occurs, control mechanisms detect conflict and adjust our behaviour. After a conflict trial (incompatible) a control mechanism is activated to reduce conflict on the following trial. However, some researchers question this model. They suggest that the Gratton effect is the result of repetitions and alternations of stimuli and/or responses. Stimulus repetitions will result in faster reaction times. In this study three Simon tasks are explored. The first task is a normal Simon task. In the second task stimulus repetitions are reduced. The third task consists of less stimulus and response repetitions. By comparing these tasks we can examine whether there is support for the stimulus-repetition model. The main analysis shows that the Gratton effect does not depend on the task. Separate analyses per task, however, show that a reversed Simon effect is present in the second task. The EEG data also shows difference in N2 activity on each task. This does not support the conflict monitoring model. More support is found for the stimulus-repetition model. Although no significant difference is found between the tasks and the Gratton effect, participants seem to behave differently on tasks which consist of less stimulus repetitions.
Item Type:Essay (Bachelor)
Faculty:BMS: Behavioural, Management and Social Sciences
Subject:77 psychology
Programme:Psychology BSc (56604)
Link to this item:
Export this item as:BibTeX
HTML Citation
Reference Manager


Repository Staff Only: item control page