International experts are gathering at the 'Within and Beyond the Brain' symposium in Porto to discuss the scientific understanding of near-death experiences, consciousness, and reports of past lives. Neuroscientist Charlotte Martial notes that 25% of cardiac arrest survivors report near-death phenomena, often involving white lights or out-of-body sensations. While some experiences can be linked to brain activity during oxygen deprivation, other mysteries, such as children's detailed accounts of past lives studied by the University of Virginia, continue to challenge conventional scientific models and the limits of materialism.