The audio segments are about 8 minutes each, or you can read the transcripts.
I found these quotes particularly insightful:
From part 1:
Still, Griffiths says all the studies in the world can't answer his central question about spirituality: "Why does that occur? Why has the human organism been engineered, if you will, for this experience?"
From part 2:
Think about a man and woman who are in love. They look at each other, and in all likelihood, something fires in their temporal lobes.
However, does that negate the presence of true love between them? Of course not. When you get to spirituality, as a scientist I think it really becomes extremely difficult to say anything other than, 'It's possible.'
From part 3:
The more you focus on something — whether that's math or auto racing or football or God — the more that becomes your reality, the more it becomes written into the neural connections of your brain.
From part 4:
After running 36 couples through this test, the researchers found that when one person focused his thoughts on his partner, the partner's blood flow and perspiration dramatically changed within two seconds. The odds of this happening by chance were 1 in 11,000. Three dozen double blind, randomized studies by such institutions as the University of Washington and the University of Edinburgh have reported similar results.
From part 5:
Some researchers look at the data and say spiritual experience is only an electrical storm in the temporal lobe, or a brain gasping for oxygen — all fully explainable by science. Others say our brains are reflecting an encounter with the divine.
And almost invariably, where a scientist stands on that issue has little to do with the clinical findings of any study. It has almost everything to do with the scientist's personal beliefs.
