Near Death Experiences Common Experiences Physical trauma Feeling

Near Death Experiences Common Experiences • • Physical trauma Feeling of floating See your body from outside, i. e. , above and looking down Sense of euphoria, calm, etc. • Begin moving/travelling • Tunnel • Meet deceased people – Normally in perfect condition – no physical deformities • Meet religious figures • Return to your body • Afterwards, the subject is likely to make life-changing choices

Factors for Consideration Physical conditions • Usually the body is physically drained – weak • Brain may be suffering from oxygen shortage or even complete lack of oxygen – Though not always • Brain may have high levels of carbon dioxide – Though not always • Body may be filled with painkillers or anesthesia – Though not always

Hallucination or Real Experience? Arguments it is real • Subjects insist the event felt very real to them, not a hallucination • Similar stories are told by people from different cultures – “Tunnel” is an almost universal feature • Accurate description of events that occurred while patient is unconscious – Accurate descriptions of words, procedures, etc. during surgery • Rarely, accurate views of objects not visible to the patient – Outside views from hospital, for example Argument it is a hallucination • Details vary by culture – Christians meet Jesus; Buddhists meet Buddha • Some events are not accurate descriptions – Detailed but incorrect descriptions of what people look like

Tunnel Vision How can we account for the tunnel experience? • Under conditions of low oxygen, the senses cease to function properly • For sight, the effect is that the peripheral vision is lost first, and the central portion last • Example – after I exercise – Dehydrated – low blood pressure – Drive home from health club – Stand my vision becomes tunnel vision • Different senses are affected differently under conditions of low oxygen or anesthesia – Sight is lost before hearing – Not uncommon that people can still hear when they are completely blind

Other Common Aspects of Stories Many similarities to dreaming • Very common to see deceased people in dreams – My sister, my parents • Many of these people lack physical deformities that they had in life – My sister is usually not blind in my dreams • Floating and flying – These are common features in my dreams – how about yours? Religious themes • Even people who are not religious often see religious figures • Nonetheless, we are all culturally aware of religions themes – My nightmare Seeing your body from outside • For true memories, we tend to picture things in first person • When we reconstruct memories, we tend to view them in third person

Reminder – How Memory Works How can we explain often accurate descriptions of events? • Recall how memory works Initial • An initial event occurs Source • This gets recorded as an engram • You later recall the information, and reconstruct the event in your mind Recall • You repeat this over many cycles • Eventually, you can’t distinguish between which aspects are real and which were reconstructed Recall Engram • Those who have experienced trauma tend to have incomplete and confusing memories • When they recall it, they try to assemble it into a coherent whole • Over time, their stories become a single consistent narrative

How to Account for Information How can we account for the accurate information later? Description of information by people later, etc. • Recall, we are better at remembering data than what its source is • Source confusion Lucky guesses and logical deductions • Most of us have some idea of what surgery looks like • And often, many details of these descriptions are inaccurate Under-anaesthetized patients • It is not uncommon for patients to wake up during surgery – Fortunately, we usually don’t remember this • Hearing is the last sense to go – Common for people to correctly report exact words spoken by doctors in surgery

Distinguishing Reality from Fantasy How do we distinguish memories from fantasies? • Both real events and imagined events produce engrams Some clues that events are real are: • The event is connected with other events you know are real – People who experienced severe trauma did have real trauma • Seeing things from third-person vs. first-person perspective – But near death experiences are normally out of body (of course) • Real events get confirmed by those around us – But since they are partly reconstructed from real events, such confirmation is not surprising

The Effects of Drugs Most of these people are drugged Some of the effects of drugs include: • Perception that the world is shrinking or enlarging – This can account for the sense of motion • Age regression – Brings back old memories • Hallucinations • Euphoria/sense of calm

A Single Coherent Picture? Can we put together a single coherent picture of these stories? • Patients have real memories of things said or done, or even seen during surgery • They also have information given to them after the fact by their doctors and visitors • And some idea what was involved • They also may have experienced – Tunnel vision – Hallucinations – Dreams • These all form engrams which they combine to make a coherent story • At first possibly incomplete, but over time it becomes more complete

Artificially Induced Near Death Experiences • Scientists have found that out of body experiences can be induced by stimulating the right temporoparietal junction of the brain – This portion of the brain is responsible for joining together all your senses into a single coherent view of “self” • Hormones released during extreme stress can cause feelings of euphoria • Dopamine, which is released in traumatic situations, can also cause hallucinations

In Summary • There are many accounts of near death experiences, from many cultures • They have similarities, but some differences, that presumably represent cultural differences • When you read popularized accounts of these events, they are rarely done from an objective viewpoint – Only the most remarkable stories tend to be published – Only the “hits” tend to be recorded, not the “misses” • It is impossible to analyze statistically/scientifically, because of the difficulty of reproducing results • Any failures can be rationalized as hallucinations, while successes are touted as proof