"[O]verall the contemporary theory considers dreaming to be a broad making of connections guided by emotion. But is this simply something that occurs in the brain or does it have a purpose as well? Function is always very hard to prove, but the contemporary theory suggests a function based on studies of a great many people after traumatic or stressful new events. Someone who has just escaped from a fire may dream about the actual fire a few times, then may dream about being swept away by a tidal wave. Then over the next weeks the dreams gradually connect the fire and tidal wave image with other traumatic or difficult experiences the person may have had in the past. The dreams then gradually return to their more ordinary state. The dream appears to be somehow "connecting up" or "weaving in" the new material in the mind, which suggests a possible function. In the immediate sense, making these connections and tying things down diminishes the emotional disturbance or arousal. In the longer term, the traumatic material is connected with other parts of the memory systems so that it is no longer so unique or extreme--the idea being that the next time something similar or vaguely similar occurs, the connections will already be present and the event will not be quite so traumatic. This sort of function may have been more important to our ancestors, who probably experienced trauma more frequently and constantly than we (at least those of us living in the industrialized world) do at present. Thus we consider a possible (though certainly not proven) function of a dream to be weaving new material into the memory system in a way that both reduces emotional arousal and is adaptive in helping us cope with further trauma or stressful events."