Excerpt from the NY Times article:

“Although antidepressants, particularly selective serotonin reuptake inhibitors and clomipramine, a tricyclic antidepressant, and behavior modification have proved effective at controlling compulsive behavior in dogs and people, they do not appear to correct underlying pathologies or causes, Dr. Ginns said. Those causes are likely to be as varied as the compulsive behaviors and as complex as the interplay of multiple genes and the environment.

“Stress and anxiety, as well as physical trauma and illness, can trigger repetitive behavior that then takes on a life of its own,” Dr. Ginns said.

But he believes that in many cases there is an underlying genetic predisposition that responds to environmental stimuli in such a way that once-normal behavior turns into something pathological. Those genetic dispositions may differ markedly between different behaviors.”

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