It’s a question that has baffled scientists for centuries – what happens in the seconds before you die?
Now, researchers from Baylor College of Medicine have taken a huge step closer to solving the mystery.
In a new study, they found that the human brain can process sophisticated language while in an unconscious state from general anaesthesia.
‘Our findings show that the brain is far more active and capable during unconsciousness than previously thought,’ explained Dr Sameer Sheth, an author of the study.
‘Even when patients are fully anesthetized, their brains continue to analyze the world around them.’
The findings challenge what we know about the role of consciousness and cognition, according to the experts.
Dr Sheth added: ‘This work pushes us to rethink what it means to be conscious.
‘The brain is doing much more behind the scenes than we fully understand.’
In a new study, researchers have found that the human brain can process sophisticated language while in an unconscious state from general anaesthesia
Consciousness is a fundamental component of cognition.
However, until now, exactly what’s going on in the brain while we’re unconscious has remained a mystery.
Writing in their study, published in Nature, the researchers explained: ‘A central question in cognitive neuroscience is the extent to which complex information processing depends on conscious awareness.
‘Prominent theories of consciousness propose that sophisticated pattern recognition, semantic interpretation and predictive processing all require conscious access.
‘At the same time, evidence from psychology and neuroscience suggests that substantial processing can occur outside awareness.’
To get to the bottom of it, the researchers recorded the brain activity of patients who were under general anaesthesia during epilepsy surgery.
In particular, the researchers focused on activity in the hippocampus – the part of the brain associated with memory.
During the surgery, the patients were exposed to repetitive tones, interrupted by an occasional different sound.
The researchers played short stories to the patients. Again, the hippocampus showed signs of real–time language processing – with the brains even able to differentiate between specific nouns, verbs and adjectives
The results revealed that the nerve cells in the hippocampus could distinguish between these unusual tones – and that this ability improved over time.
According to the experts, this suggests a form of learning going on in the unconscious brain.
Next, the researchers played short stories to the patients.
Again, the hippocampus showed signs of real–time language processing – with the brains able to differentiate between specific nouns, verbs and adjectives.
Amazingly, the researchers found that their brains could even predict upcoming words in a sentence.
‘This kind of predictive coding is something we associate with being awake and attentive, yet it’s happening here in an unconscious state,’ explained co–author Dr Benjamin Hayden.
Overall, the findings suggest that language processing does not require consciousness.
However, the researchers highlight that more research is needed before we can say with certainty that the brain can still process language in the seconds before death.
‘Anaesthesia has an uncertain relationship with waking life,’ they explained in the study.
‘Moreover, it remains unclear whether our findings will apply to other non–conscious states, such as sleep and coma.’
The news comes shortly after research revealed the dreams you’ll probably have as you near your end.
Experts from Azienda USL–IRCCS di Reggio Emilia surveyed more than 200 carers of terminally ill people about their end–of–life dreams and visions (ELDVs).
And the results revealed several common themes.
Many reported vivid dreams featuring lost loved ones, while others saw symbols of transition, including doors, stairways and light.
