As the body nears the end of life, sensory perception changes, raising questions about which senses decline and which persist longest.
Understanding Sensory Changes
As the body’s systems slow near the end of life, sensory perception is impacted. This decline is a natural consequence of reduced blood flow, organ function changes, and shifts in brain activity. Not all senses diminish at the same rate, and the order of their fading can vary, though general patterns are observed.
Typically, senses like sight, taste, and smell tend to decline earlier in the dying process. Vision may become blurred, and a person’s eyes might appear glazed or unresponsive to external stimuli. The ability to distinguish tastes and smells can also lessen, making food less appealing or even altering its perception.
Touch sensitivity, including the perception of pain, can also decrease as the body’s systems become less responsive. As physical energy wanes, individuals often become more withdrawn and enter periods of unresponsiveness. These changes reflect the body conserving its remaining energy, leading to a gradual disengagement from the external environment.
Hearing: The Final Sense
Among the senses, hearing is widely considered the last to fade for many individuals approaching death. This observation, long noted by healthcare professionals, has gained scientific support through recent research.
One study, conducted by researchers at the University of British Columbia and published in Scientific Reports, investigated brain activity in hospice patients nearing death. Using electroencephalography (EEG), which measures electrical activity in the brain, the team monitored responses to various sound patterns in both conscious and unresponsive patients, comparing them to healthy control participants. The findings revealed that the brains of dying patients, even those hours away from death and appearing unconscious, responded to auditory stimuli in a manner similar to healthy individuals.
Specific brain signals, such as the MMN (Mismatch Negativity) and P3a/P3b responses, which indicate the brain’s automatic processing of sound changes, were observed. This suggests that while a dying person may not be able to communicate or show outward signs of awareness, their auditory pathways remain active. While the research supports the persistence of hearing, it does not confirm whether individuals consciously comprehend what they are hearing or understand language.
Communicating with a Dying Loved One
Given the evidence that hearing may persist until the very end, continuing to communicate with a dying loved one can be meaningful. Even if they appear unresponsive, speaking to them can offer comfort and reassurance during their final hours. This practice can also provide solace to family members and caregivers, helping them feel connected and present.
Speaking calmly and clearly, using a gentle tone, and sharing memories or expressing love can create a comforting environment. Many healthcare providers recommend assuming the person can still hear and benefit from familiar voices.
These interactions can offer a sense of peace for the dying individual, potentially easing their transition. For those left behind, speaking and connecting can provide a sense of closure and affirmation of their bond.