Abstract: A plurality of circular RNAs (circRNAs) the expression of which is correlated with brain disorders. The circRNAs are useful for compositions, kits, assays, and methods for the identification, diagnosis, screening, treatment and/or monitoring of brain disorders including psychiatric disorders such as bipolar disorder (BD), schizophrenia (SCZ), depression, Attention-Deficit/Hyperactivity Disorder (ADHD), Obsessive-compulsive disorder (OCD), Anxiety Disorders, etc., and neurodevelopmental disorders such as Autism, Asperger's Syndrome, and other Autism Spectrum Disorders (ASD), pervasive developmental disorders not otherwise specified (PDD-NOS), etc.