During this study, the investigators hope to better find out if NIR TLT is helpful for treating depression. The investigators will do this by comparing the effects of TLT ("active treatment") NIR device to a sham treatment (which is an inactive or "pretend" treatment) device. The sham ("pretend") device looks exactly like the NIR device but will not use a near-infrared radiation during the study visits. There are two sets of identical devices that will be used in this study, producing active and sham treatment, respectively. The devices work exactly the same when you are receiving active treatment and sham treatment, except that the devices will produce therapeutic transcranial LED energy during the active treatment sessions but it will not produce this LED energy during the sham treatment sessions.