Intriguingly, a following study showed that the proportion of PPD+ cells in SOM+ neurons of S1BF can fluctuate dynamically during tactile information-associated learning (Loh et al. 2017), implying that the dynorphin expression level in the neocortex may represent a functional state of SOM+ neurons that are sensitive to developmental and environmental factors underlying human psychiatric disorders (Casello et al. 2022). Here, GRHL3 is linked to psychiatric disorder.