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Updated: May 29, 2026
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Motion-Acuity Test for Visual Field Acuity Measurement with Motion-Defined Shapes
Published on: February 23, 2024
Performance Dip in motor response induced by task-irrelevant weaker coherent visual motion signals
Yuko Yotsumoto1, Aaron R Seitz, Shinsuke Shimojo
1Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129, USA.
Cerebral Cortex (New York, N.Y. : 1991)
|September 24, 2011
Summary
A weaker stimulus, not a stronger one, disrupted a task more, revealing the "Performance Dip." This phenomenon involves the supplementary motor area (SMA) and pre-SMA, not the DLPFC, suggesting a common neural basis for unconscious processing.
Area of Science:
- Cognitive Neuroscience
- Behavioral Psychology
- Neuroscience
Background:
- The Performance Dip is a novel behavioral finding where weaker irrelevant stimuli cause greater task disruption than stronger ones.
- Understanding the Performance Dip offers insights into unconscious processing and attentional mechanisms.
- Previous research linked the Performance Dip to the dorsolateral prefrontal cortex (DLPFC).
Purpose of the Study:
- To investigate the generalization of the Performance Dip phenomenon.
- To determine if the Performance Dip occurs in a motion-related Simon task.
- To identify the specific brain regions (DLPFC vs. SMA/pre-SMA) involved in the motion-related Simon task Performance Dip.
Main Methods:
- Participants performed a letter identification task with manual directional responses based on dot color.
- Task-irrelevant stimuli involved the global direction of stochastic moving dots (congruent or incongruent).
- Brain activity was implicitly assessed by comparing performance under different stimulus conditions, focusing on DLPFC vs. SMA/pre-SMA involvement.
Main Results:
- A Performance Dip was observed in the motion-related Simon task, with weak incongruent stimuli causing significant disruption.
- The supplementary motor area (SMA) and pre-supplementary motor area (pre-SMA) were critically involved, not the DLPFC.
- This suggests that the neural mechanisms underlying the Performance Dip may differ across tasks and brain regions.
Conclusions:
- The Performance Dip extends to motion-based tasks, indicating a broader applicability of the phenomenon.
- The involvement of SMA and pre-SMA suggests these areas play a key role in processing weak, intrusive, task-irrelevant information.
- Findings propose a common neural mechanism where weak, uninhibited information can disrupt cognitive tasks, shedding light on unconscious processing.
