Similarly, roflumilast, which is also a PDE4 inhibitor, is nowadays a treatment for chronic obstructive pulmonary disease and was suggested as a cognitive enhancer in schizophrenia through enhancing the amplitude of mismatch negativity, working memory‐related theta oscillations, and verbal memory with normalization deficits in attentional set‐shifting and learning‐related activity impairments by increasing intracellular cAMP in brain areas implicated in cognitive deficits in patients with schizophrenia.41, 42, 43. This evidence concerns the gene PDE4A and schizophrenia.