A new study by French and Israeli researchers – due out next month in the journal NeuroImage – details how the human brain protects itself from thoughts of death to optimise function by categorising it as an unfortunate event that only ever befalls other people.
“The brain does not accept that death is related to us,” said co-author Yair Dor-Ziderman from the Bar Ilan University in Israel. “We have this primal mechanism that means when the brain gets information that links self to death, something tells us it’s not reliable, so we shouldn’t believe it.”
According to Dor-Ziderman, this usually comes online early in life, or as soon as we come to realise that one day we’re going to die and there’s nothing that can be realistically done about it. Since thoughts about the inevitability of our own demise go “against the grain of our whole biology, which is helping us to stay alive” the brain does all in its power to put them out of the picture.
The study had volunteers looking at faces – both their own and those of strangers – flashing up on a screen, followed by an image of a different, as-yet-unseen face, to figure out how the brain’s prediction system operates when presented with surprise images.
As expected, upon seeing the final human face – which had not showed up in the series of flashing images before – appeared on the screen, the brain fluttered with surprise due to subverted expectations.
However, since each face was also accompanied by different words, half of which were related to mortality, once a subject’s own face appeared next to some deathly words, the brain shut down its prediction system and no signals indicating surprise were detected for that image/word pair.
“This suggests that we shield ourselves from existential threats, or consciously thinking about the idea that we are going to die, by shutting down predictions about the self, or categorising the information as being about other people rather than ourselves,” said lead author Avi Goldstein.
The researchers speculate that – apart from the brain’s general aversion to thoughts of death, which may constitute an obstruction to daily life – such denial may also be the product of how modern societies shunt sick people to hospitals and the elderly to care homes, thereby allowing us very little time to come to terms with actual death and dying.