CDK5 and schizophrenia: Indeed, interference in NRG1/ErbB4 and p35/Cdk5 signaling has been associated with epilepsy (Dhavan and Tsai 2001; Li et al. 2011; Tan et al. 2011) and schizophrenia (Engmann et al. 2011; Marín 2012), in both mice and humans.