Hearing is widely thought to be the last sense to go in the dying process. Now UBC researchers have evidence that some people may still be able to hear while in an unresponsive state at the end of their life.
This research, published recently in Scientific Reports, is the first to investigate hearing in humans when they are close to death.
Using electroencephalography (EEG), which measures electrical activity in the brain, the researchers analyzed data collected from healthy control participants, from hospice patients when they were conscious, and from the same hospice patients when they became unresponsive. The patients were receiving palliative care at St. John Hospice in Vancouver.
"In the last hours before an expected natural death, many people enter a period of unresponsiveness," says study lead author Elizabeth Blundon, who was a PhD student in the department of psychology at the time of the study. "Our data shows that a dying brain can respond to sound, even in an unconscious state, up to the last hours of life."
This new insight into the dying brain's response to sound can help family and friends bring comfort to a person in their final moments.
The researchers introduced study participants to various patterns of common and rare sounds that changed frequency. When the rare tone pattern occurred, both groups responded by giving a pre-arranged signal.
The researchers monitored the brain's response to those tones using EEG and found that some dying patients responded similarly to the young, healthy controls -- even when they were hours away from death.
"We were able to identify specific cognitive processes from the neuro-typical participants as well as the hospice patients," says Lawrence Ward, a professor in the department of psychology at UBC. "We had to look very carefully at the individual control participants' data, to see if each one of them showed a particular type of brain response before we felt confident that the unresponsive patient's brain reacted similarly."
This study was adapted from a European study that explored brain responses to sound in individual healthy participants, and in minimally conscious and unresponsive brain-injured patients. The UBC researchers applied a similar paradigm to actively dying unresponsive patients.
Blundon and Ward collaborated with Dr. Romayne Gallagher, a palliative care physician at St. John Hospice who has since retired. The research required patients to give their consent in advance. Thirteen families participated and brain recordings were obtained from five patients when they were unresponsive.
In Gallagher's 30 years of treating dying patients, she has witnessed positive reactions in people when loved ones spoke to them in their final moments. Gallagher and her colleagues often wondered if hearing was the last sense to go. She contacted Ward to see if this theory could be proven.
"This research gives credence to the fact that hospice nurses and physicians noticed that the sounds of loved ones helped comfort people when they were dying," says Gallagher. "And to me, it adds significant meaning to the last days and hours of life and shows that being present, in person or by phone, is meaningful. It is a comfort to be able to say goodbye and express love."
Blundon says what while the evidence of brain activity supports the idea that a dying person might be hearing, they can't confirm whether people are aware of what they're hearing.
"Their brains responded to the auditory stimuli, but we can't possibly know if they're remembering, identifying voices, or understanding language," says Blundon. "There are all these other questions that have yet to be answered. This first glimpse supports the idea that we have to keep talking to people when they are dying because something is happening in their brain."
FAQs
If your loved one in hospice care becomes nonverbal and unresponsive, it's easy to believe the misconception that they can't hear you. A recent study, however, reveals that hearing is the last sense that remains for dying patients.
What are common symptoms in the last 48 hours of life? ›
Changes in the last hours and days of life
- Becoming drowsy. You'll start to feel more tired and drowsy, and have less energy. ...
- Not wanting to eat or drink. Not wanting to eat is common in people who are dying. ...
- Changes in breathing. ...
- Confusion and hallucinations. ...
- Cold hands and feet. ...
- More information.
- Why do changes happen at the end of life? When someone's dying, the body slows down and shows signs that the person is approaching the end of their life. ...
- Losing weight. ...
- Feeling weak and sleeping more. ...
- Feeling hot or cold. ...
- Eating and drinking less. ...
- Bladder and bowel problems. ...
- Breathlessness. ...
- Noisy breathing.
Four-Six Days Before Death
As the oxygen supply to the brain decreases, they may experience severe agitation or hallucinations that are inconsistent with their normal manner or personality, such as pulling on bed linens or clothing. You can talk to them in a calm voice and reassure your loved one that you are there.
What is likely to happen 2 weeks prior to death? ›
1 to 2 weeks before death, the person may feel tired and drained all the time, so much that they don't leave their bed. They could have: Different sleep-wake patterns. Little appetite and thirst.
How do you know when a hospice patient is transitioning? ›
When a patient is transitioning, they are typically bedbound due to exhaustion, weakness, and fatigue. They are less responsive and sleeping most of the time. They may sluggishly rouse when you tap them on the shoulder. They may have a more difficult time waking up.
How do you know when someone is in the last days of life? ›
Needing more sleep. They are likely to spend more time sleeping, and will often be drowsy even when they are awake. They may also drift in and out of consciousness. Some people become completely unconscious for periods of time before they die - this could be for a short period or as long as several days.
What are the 8 signs and symptoms that death is imminent? ›
Physical signs that death is near include:
- mottled and blotchy skin, especially on the hands, feet and knees.
- blood pressure decreases.
- they can't swallow.
- less urine (wee) and loss of bladder control.
- restlessness.
- difficult breathing.
- congested lungs.
Certain physical changes may occur in a person at the end of life:
- They may feel tired or weak.
- They may pass less urine, and it may be dark in color.
- Their hands and feet may become blotchy, cold, or blue. ...
- Their heart rate may go up or down and become irregular.
- Blood pressure usually goes down.
The brain is the first organ to begin to break down, and other organs follow suit. Living bacteria in the body, particularly in the bowels, play a major role in this decomposition process, or putrefaction. This decay produces a very potent odor, known as the smell of death.
Often before death, people will lapse into an unconscious or coma-like state and become completely unresponsive. This is a very deep state of unconsciousness in which a person cannot be aroused, will not open their eyes, or will be unable to communicate or respond to touch.
What is the most common hour of death? ›
Your body clock doesn't just make you feel hungry and sleepy - it also influences when you die, according to science. The time people are most likely to die is 11am, according to Harvard Medical School research published in 2012.
What happens in the last 5 minutes before death? ›
Physical signs of dying
Facial muscles may relax and the jaw can drop. Skin can become very pale. Breathing can alternate between loud rasping breaths and quiet breathing. Towards the end, dying people will often only breathe periodically, with an intake of breath followed by no breath for several seconds.
What happens in the first 30 minutes of death? ›
As the blood pools, patches appear on the skin within 30 minutes of death. About two to four hours postmortem, these patches join up, creating large dark purplish areas towards the bottom of the body and lightening the skin elsewhere. This may be less apparent on darker skin. This process is called livor mortis.
What is the hardest thing to witness in hospice? ›
The most challenging aspect of witnessing a loved one's journey through hospice can be seeing them experience physical decline, emotional distress, and pain. It can also be difficult to accept that curative treatments are no longer an option and adjusting to a new focus on comfort measures only.
How to tell when an elderly person is nearing the end? ›
What are the signs that someone is dying?
- feeling weak and tired.
- sleeping more or being drowsy.
- feeling hot or cold.
- cold hands or feet.
- eating and drinking less.
- bladder or bowel problems.
- breathlessness (dyspnoea)
- pain.
The dying person will feel weak and sleep a lot. When death is very near, you might notice some physical changes such as changes in breathing, loss of bladder and bowel control and unconsciousness. It can be emotionally very difficult to watch someone go through these physical changes.
What are common feelings when nearing the end of life? ›
You may have many strong emotions. After the initial shock, it's common to have feelings of fear, denial, anger, despair, helplessness, anxiety and depression. Your emotions might change, sometimes from day to day or even from hour to hour. This is part of the process of making sense of what is happening.
How long do end of life symptoms last? ›
At the end-of-life. The end-of-life period—when body systems shut down and death is imminent—typically lasts from a matter of days to a couple of weeks. Some patients die gently and tranquilly, while others seem to fight the inevitable.
