Thirteen years have passed since the neurogenic hypothesis of depression was postulated. One of its aspects, that decreased
neurogenesis could be causative of the onset of depression has been difficult to prove. Another aspect, the prediction that increasing neurogenesis
would not only be supportive but also required to produce clinical results by antidepressants has gathered experimental validation.
Thus a question arises: should new antidepressant strategies based solely on increasing neurogenesis be pursued? At the risk of disappointing
the audience, we will not provide a straight answer to this question in this review, but we do hope to enlighten the reader regarding
what is known about adult hippocampal neurogenesis, the indications and evidence of its involvement in the onset and treatment
of depression, and the advances that have been made in the field in recent years. As we will recount here, the main body of support in favor
of the neurogenic hypothesis of depression is based more on intimation than actual proof. However the rare examples that provide
support are sufficiently robust to justify investment of resources and effort to clarify the issue, even if the involvement of neurogenesis,
both in the etiology and the treatment of depression, is only partial and comprises only subtle components of this complex mental disorder.