Suicidal behaviors (SB) are a major health problem in France:10,000 suicides and 220,000 suicide attempts every year. SB management is therefore a major public health issue. Recently, investigators have demonstrated the interest of acceptance and commitment therapy (ACT) as an add-on treatment to reduce intensity and severity of suicidal ideation in depressed patients having a history of suicide attempt within previous year (i.e actual SB disorder according to the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5)). Based on structural and functional findings, it is admitted orbitofrontal and ventral prefrontal cortices play a role in suicidal vulnerability. Interestingly, previous functional MRI (fMRI) studies have also reported the modulation of these regions by ACT in subjects suffering from chronic pain. fMRI could thus be an interesting tool to identify biomarkers of SB and its improvement by ACT.