Learning and brain plasticity in mental disorders.

This special issue assembles studies that show the importance of learning and brain plasticity processes for the understanding of mental disorders. Most approaches to mental illness have examined the molecular or psychosocial factors underlying these disorders but have not focused on specific mechanisms such as learning or memory processes or brain plasticity nor have they examined these processes across disorders. Rather than taking a nosological approach, which leads to the problem of overlapping psychopathological characteristics and examining the neurobehavioral and molecular mechanisms of individual disorders, we suggest to determine similarities and differences of the underlying mechanisms of learning and neural plasticity across a variety of disorders. For example, rather than identifying genes related to anxiety disorder or addiction – very broad concepts – our approach focuses on genes related to Pavlovian fear conditioning and its extinction, glutamatergic signaling, plasticity of the amygdala or the orbitofrontal cortex, to