We humans really did something when we learned how to resuscitate people who had gone into cardiac arrest, because (by our understanding of biology at the time, at least) it meant we had learned how to bring people back from the dead. They may have been without a heartbeat for only a matter of seconds, sure, but when we began waking them up, we gained an opportunity: the chance to ask what it feels like to die.

These moments on the periphery of life and death are known widely as near-death experiences, and there are plenty of accounts. However, in a paper published in 2014, a group of scientists decided to take the subject one step further by speaking to survivors to systematically study near-death experiences for the first time.

All the participants were survivors of cardiac arrest, and in total there were 101 who completed the full set of interviews. Speaking to them revealed that 46 percent had memories of their near-death experience, and the stories they tell are haunting, to say the least. They also revealed seven major cognitive themes:

• Fear: “I was terrified. I was told I was going to die and the quickest way was to say the last short word I could remember.” 
   “Being dragged through deep water with a big ring and I hate swimming—it was horrid.”
• Animals or plants: “All plants, no flowers.” 
   “Saw lions and tigers.”
• Bright light: “The sun was shining.” 
   “Recalled seeing a golden flash of light.”
• Family: “Family talking 10 or so. Not being able to talk to them.” 
   “My family (son, daughter, son-in-law and wife) came.”
• Being persecuted or experiencing violence: “Being dragged through deep water.” 
   “I had to go through a ceremony and[…] the ceremony was to get burned. There were four men with me, whichever lied would die… I saw men in coffins being buried upright.”
• Deja vu experiences: “…experienced a sense of De-ja vu and felt like knew what people were going to do before they did it after the arrest. This lasted about 3 days”
• Events occurring after initial recovery from cardiac arrest: “a tooth coming out when tube was removed from my mouth”

Some accounts also appeared to demonstrate that the person in cardiac arrest was able to recall details of what had happened when their heart wasn’t beating (so when they were supposed to be dead). The explanation for this may lie in the recent discovery of conscious activity in the dying brain.

One participant spoke of how they had heard voices saying “shock the patient” while being beckoned by a woman on the ceiling. When they joined the mysterious woman, they could see themselves and the doctors and nurses working on them, and records from the emergency department backed up that what they had seen was accurate.

Beyond being interesting, understanding near-death experiences better can assist patients who experience post-traumatic stress disorder after cardiac arrest, which is hardly surprising when you hear what they experienced.

“[Cardiac arrest] survivors experience a broad range of memories following CPR including fearful and persecutory experiences as well as awareness,” concluded the authors. “While explicit recall of [visual awareness] is rare, it is unclear whether these experiences contribute to later PTSD. Studies are also needed to delineate the role of explicit and implicit memory following [cardiac arrest] and the impact of this phenomenon on the occurrence of PTSD and other life adjustments among [cardiac arrest] survivors.”

The study is published in the journal RESUSCITATION.