I get like this, particularly when my depression is worse. It is a well recorded symptom of depression. I'm not sure what function it serves, but I feel sometimes I feel that it can help slow me down when everything is completely overwhelming and protect me from the pain I can't handle. Often at the same time I shut down so I can't feel myself or anything much. I may be disoriented and unable to process information or sensations. It's horrible, but, I think, maybe not as unmanageable as how I would otherwise feel. Does this make sense?