Even when we are now dying and no longer responding to external stimuli, seeming inert and passive, our brain continues to hear the words and sounds that come from outside: hearing is in fact the last of the five senses to go out. This is shown by a study by the University of British Columbia, published in the journal Scientific Reports, conducted on the patients of a Vancouver hospice when they were still conscious and on the same when they were no longer.
Using the electroencephalogram, researchers led by Elizabeth Blundon compared the data of these patients with those of healthy people. "In the last hours before an impending natural death, many people enter a phase of non-responsiveness - explains Blundon - Our data show that a dying brain still manages to respond to sound, even in a state of unconsciousness, until the last hours of life ". The researchers used different types of sounds, common and rarer, at different frequencies. The brain response was monitored with the electrocardiogram, detecting that some patients, even a few hours after their departure, responded in a similar way to young and healthy ones. "We were able to identify specific cognitive processes in both groups - adds Lawrence Ward, one of the researchers - by noting that the brains of the patients, who no longer responded, reacted in a similar way to that of the other study participants".
This research gives credit to what "already found in the work experience by hospice doctors and nurses, according to which the sounds of loved ones give comfort to those who are leaving," adds Gallagher. However, the researchers could not confirm that people are aware of what they feel. "We cannot know if they are remembering, identifying the voice or understanding the language - he concludes - while responding to the auditory stimulus. The idea, however, is that we must continue talking to people when they are dying because something happens in their brain".