Indeed, it is not possible to develop animal models with face validity to human suicide. However, construct-valid approaches including those reliant on neurobiology, genetics and in particular endophenotypes, such as those discussed in this review, can be used.28, 73, 74 Some examples would be the behavior of mice in tests that assess their decision-making process, or levels of impulsive aggressive behavior, for example, a rodent version of the Iowa gambling task exists where the profile in choice behavior retains many of the key characteristics of the human task.75, 76 Serotonin transporter levels have been shown to modulate long-term decision making in this task in the rat (as it has been previously shown in humans)77 and Iowa gambling task impairment has been associated with a decrease in 5-HIAA levels in the orbitofrontal cortex in a rat chronic pain model.78 The proposed link between this main metabolite of serotonin, orbitofrontal cortex function and decision making is significant, as deficiencies in these three parameters are implicated in suicide vulnerability. Drugs with recognized antisuicidal or prosuicidal effects provide a mechanism to assess the predictive
