The functional neuroanatomy of tasks that recruit different forms of response selection and inhibition has to our knowledge, never been directly addressed in a single fMRI study using similar stimulus-response paradigms where differences between scanning time and sequence, stimuli, and experimenter instructions were minimized. Twelve right-handed participants were scanned on two standard cognitive control tasks, a stimulus-response incompatibility task, and a response inhibition task. A compound trial design allowed comparison of preparing to inhibit an upcoming automatic response to wholly inhibiting an automatic response. Furthermore, inhibiting an automatic response to perform an alternative task-relevant response was compared to wholly inhibiting an automatic response. No differences were found in prefrontal activity when preparing to inhibit an automatic response was compared to wholly inhibiting an automatic response, suggesting a mostly common network. The left inferior frontal gyrus was found to be commonly recruited during both tasks when controlled responses were required, likely due to its role in response selection. In contrast, the right inferior frontal gyrus was found to be more involved when task demands were stronger for response inhibition. Our results are largely consistent with models of cognitive control that postulate that separate psychological constructs, such as response selection and inhibition, are related processes largely served by a common prefrontal network. This prefrontal network is recruited to a greater or lesser extent depending on specific task demands.
Bibliographical noteFunding Information:
Ms. Goghari was supported by a PGS Master’s and Doctoral Award from the Natural Sciences and Engineering Research Council of Canada and by the Graduate Research Partnership Program, University of Minnesota. Grant support was provided by: Grant-in-Aid of Research, Artistry and Scholarship University of Minnesota, R21MH079262, R01MH066629, BTRR P41 008079, and the MIND Institute. The authors gratefully acknowledge the assistance of Melissa Johnson, Kate Fissell, Rudrava Roy, and the staff at the Center for Magnetic Resonance Research. Data from this study were presented at the Human Brain Mapping Conference, June 11–15th, 2006 in Florence Italy.
- Cognitive control
- Executive functioning
- Functional magnetic resonance imaging
- Inferior frontal gyrus
- Prefrontal cortex
- Response incompatibility