Medical systems, devices, and methods provide improved radiosurgical techniques for treatment of anxiety disorders (such as Post-Traumatic Stress Disorder (PTSD), Generalized Anxiety Disorder (GAD), Panic Disorder, Social Phobia, Specific Phobia, and the like). Radiation can be directed from a radiation source outside the patient toward a target tissue deep within the patients brain using a stereotactic radiosurgical platform, typically without having to impose the surgical trauma associated with accessing deep brain tissues. The target will often include at least a portion of the amygdala, with exemplary treatments being directed to targets that are limited to a sub-region of the amygdala. Rather than applying sufficient radiation to kill the neural tissue within the target, a cellularly sub-lethal dose of the radiation may be applied. Without imposing frank cell death throughout the target, the radiation can mitigate the anxiety disorder, obesity, or the like, often by modulating the level of neural activity within the target and in associated tissues.