Saying "conscience" is just electrical signal is borderline retarded! Even top of the line biophysicist and neuro-biologist are not sure of what makes us self aware and at most, we have elegant thories:
http://journal.frontiersin.org/Journal/10.3389/fpsyg.2011.00004/fullWhat I never got is that I am still "conscious" even when my sense are totally deprived. That part, I never understood: no stimuli, yet there is a response.
I don't know what happens after death but I suspects something survives. I don't think evolution as an end, the universe is far too vast, complex and perfect in it's design to be just the fruit of pure chaos. Matter is self-organizing and most of the time, the most complex organisms seem to be more than just the sum of their part.
Besidesm there seems to have been a great number of people that "stumbled" upon a deeper meaning to our lives and have lived life that are, by all account, extraordinary (Jesus, Bouddha, Mahommet, Kristnamurthi etc...). Judging by their results and the peace of mind they attained, it seems to be reasonable that there might be something more than just the materialistic interpretation of reality.
But it is a very polar issue: believer and materialists will never agree on that, each having evidence to support their claim. In my opinion, saying science can explain everything is arrogant and borderline psychotic.