Inhibitory Control and the Structural Parcelation of the Right Inferior Frontal Gyrus

Rune Boen; Liisa Raud; Rene J Huster

doi:10.3389/fnhum.2022.787079

Inhibitory Control and the Structural Parcelation of the Right Inferior Frontal Gyrus

Front Hum Neurosci. 2022 Feb 24:16:787079. doi: 10.3389/fnhum.2022.787079. eCollection 2022.

Authors

Rune Boen^{1

2

3}, Liisa Raud^{4

5}, Rene J Huster^{1

4

6}

Affiliations

¹ Multimodal Imaging and Cognitive Control Lab, Department of Psychology, University of Oslo, Oslo, Norway.
² Department of Medical Genetics, Oslo University Hospital, Oslo, Norway.
³ NORMENT, Division of Mental Health and Addiction, Oslo University Hospital and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
⁴ Cognitive and Translational Neuroscience Cluster, Department of Psychology, University of Oslo, Oslo, Norway.
⁵ Center for Lifespan Changes in Brain and Cognition, Department of Psychology, University of Oslo, Oslo, Norway.
⁶ Sleep Unit, Department of Otorhinolaryngology/Head and Neck Surgery, Lovisenberg Diakonale Hospital, Oslo, Norway.

Abstract

The right inferior frontal gyrus (rIFG) has most strongly, although not exclusively, been associated with response inhibition, not least based on covariations of behavioral performance measures and local gray matter characteristics. However, the white matter microstructure of the rIFG as well as its connectivity has been less in focus, especially when it comes to the consideration of potential subdivisions within this area. The present study reconstructed the structural connections of the three main subregions of the rIFG (i.e., pars opercularis, pars triangularis, and pars orbitalis) using diffusion tensor imaging, and further assessed their associations with behavioral measures of inhibitory control. The results revealed a marked heterogeneity of the three subregions with respect to the pattern and extent of their connections, with the pars orbitalis showing the most widespread inter-regional connectivity, while the pars opercularis showed the lowest number of interconnected regions. When relating behavioral performance measures of a stop signal task to brain structure, the data indicated an association between the dorsal opercular connectivity and the go reaction time and the stopping accuracy.

Keywords: inhibitory control; response execution; response inhibition; right inferior frontal gyrus; structural parcelation.