What is a dream really?

What does it mean when you have a really long dream about an ex?

• I had a really long dream about an ex where we were both trying to contact each other. It was so strange because I could see from his point of view and mine. In my dream I tried contacting him through his mom and through his facebook or whatever. His mom responded back saying that he was looking everywhere for me, and then his dad ended up knocking on my apartment door saying the same thing... Towards the end of my dream I finally united with him somehow(I cannot remember how). He said something to me that was relieving to hear, but I just cannot seem to remember what it was. Also, I remember seeing his baby sister in my dream... She was an infant. By this time she should be almost two years old. Does that mean anything? I saw almost everyone in his family in this dream, his brothers, father, mother, step father, and two young sisters. I remember a fire place in the background, but it was not on. For some reason the fireplace really stands out to me even though it is something so normal. The strange part aside from the dream is that we haven't spoken in almost two years. And the last time that I even heard from him was him telling me that he had a dream about me, but I do not know what it was about. This is the first time that I have had a dream about him since our relationship ended... and also he never crosses my mind. I do not understand. I mean I even am engaged to married and everything... If you guys could tell me some facts about dreams or some meaning about the events that happened in my dream that would be great. Has anyone experienced anything similar to this? Maybe I am reading too much into this... But it has been stuck in my head all day. Help? Thanks.

• Answer:

  Dreams combine our perceptions, preferences, desires, and fears with hallucinogenic processes of the unconscious mind. “Internally generated activity is modulated by sensory input (perception). … Asleep vision (dreaming) is perception not tied down to anything in the real world. … What we call normal perception does not really differ from hallucinations, except that the latter are not anchored by external input.” (pages 44-46) “A popular model of the neuroscience literature suggests that dream plots are stitched together from essentially random activity: discharges of neural populations of the mid-brain (p. 139)” In other words, things we see, hear, taste, or feel are incorporated into internally generated mental activity of a hallucinatory nature; therefore, dreams do not necessarily have any meaning; although they may reflect our perceptions, preferences, desires, and fears. “Incognito: The Secret Lives of the Brain,” by Dr David Eagleman, who directs the Laboratory for Perception and Action and the Initiative on Neuroscience and Law, Baylor College of Medicine