Although adult hippocampal neurogenesis has been reported to be very small in human subjects, applicability of animal neurogenesis research to human disorders is still a current investigative focus. Recent studies have implicated adult-born hippocampal neurons in pattern separation, a process where similar experiences or events are transformed into discrete, non-overlapping representations. The authors of this paper review this data and propose that impaired pattern separation underlies the overgeneralization often seen in anxiety disorders, specifically post-traumatic stress disorder and panic disorder, and therefore represents an endophenotype for these disorders. They suggest that development of new drugs which promote adult neurogenesis may have therapeutic potential for patients who display pattern separation deficits.

Kheirbek MA, Klemenhagen KC, Sahay A and Hen R: Neurogenesis and generalization: a new approach to stratify and treat anxiety disorders. Nature Neuroscience 15:1613–1620 (2012).

http://www.nature.com/neuro/journal/v15/n12/full/nn.3262.html