Dorsolateral Frontal Cortex
The landmarks for delineating dorsalateral frontal cortex include:
- Anterior, horizontal ramus of the sylvian fissure
- Lateral orbital sulcus
- Superior frontal sulcus
- Circular insular sulcus and gyrus
- Precentral sulcus
The dorsalateral cortex is traced in the coronal plane. Tracing begins on the most anterior coronal slice in which the olfactory sulcus can be delineated (Fig. 1). The most medial and dorsal section of the superior frontal sulcus is the medial boundary of the DLFC while the frontomarginal sulcus is the lateral boundary (Fig. 1). As you move posteriorly, the superior limit of the lateral orbital sulcus becomes the lateral boundary (Fig. 2). When the lateral orbital sulcus is no longer visible and the orbital gyrus and precentral gyrus appear, the superior segment of the circular insular sulcus then becomes the medial and inferior boundary while the inferior precentral sulcus becomes the lateral and inferior boundary (Fig. 3). The most posterior coronal section in which the medial orbital gyrus can be distinguished is the last slice in which to trace the DLFC (Fig. 4).