Behavioral disorders: The 'blind spot' of neurology and psychiatry.

Behavioral disorders occupy the crossroads between neurology and psychiatry, and emerging disorders, such as frontotemporal lobar degeneration of genetic origin and autoimmune encephalitis, can present with both neurological and psychiatric signs. Thus, the primary aim of this introductory article is to review frequently encountered behavioral clinical features, such as apathy and agitation, and their related syndromes, including frontal and anterior temporal syndromes. These behavioral states and their underlying etiologies are also here illustrated with clinical case reports. In addition, this review highlights the idea that in order to progress in the understanding and management of behavioral disorders, there needs to be a strong interest towards developing new forms of cooperation between neurologists, psychiatrists and neuroscientists, such as those who work at university-based hospital neuropsychiatric clinical units.