Hardcore materialists reduce mankind's spirituality into solid matter. Reality is only preceived through the senses and the brain.

From what I've seen, they use logic to make their points that seem to go in circles and end up with more confusion, uncertainy and darkness. There is no light at the end of the tunnel on this path.

Any spirituality in the term "I am" is lost" when the "I am" is dropped from the term "I am a brain." The person become trapped as a brain (a creation) rather than a creator(spirit).

There are some materialists, however, who see consciousness as more than the product of a brain.  

An atheist who had the above point a view changed it when he had a Near Death Experience.   His consciousness was expanded into spiritual realms.

Near-death-experiences can open realities and possibilities that most can only dream about. Near death can be a consciousness expanding event.

Dr. Stephen Greer had a near death experience in 1973 that opened up his mind to possibility of communication with extraterrestrials. He calls this CE5, close encounters with aliens initiated by a human being. He's been practising these CE5 techniques for 40 years with some success.

If a person learns by his mistakes, there has to be better storage place for memories than in the brain where they can get destroyed. The akaskic records is one such place. This is the backup memory system plugged into the souls of earthy visitors. 

On Star Trek, memories can be recreated through the use of a holodeck and holograms. Some of these holograms end up as being senient. 

Personally, I've tried to use advanced memory systems as a way to understand Jesus Christ and The Kingdom of Heaven better. "Ask and it will be given. Knock and the door will be opened to you."

Is there a spiritual side to mankind? Check out the movies "Field of Dreams", "Ghost" " What Dreams May Come" and ask yourself what are they really about?