Beyond lifespan and healthspan: a biological framework for experienced longevity

Area of Science:

• Gerontology
• Cognitive Neuroscience
• Psychology of Time

Background:

• Aging research traditionally focuses on lifespan and healthspan.
• Chronological time is often treated as a uniform measure of aging.
• The subjective reconstruction of time in aging has not been systematically studied.

Purpose of the Study:

• Introduce and define "experienced longevity" as a novel aging variable.
• Examine how memory structures the subjective experience of time in aging.
• Propose a model linking neuroenergetic changes to temporal perception.

Main Methods:

• Drawing on theories of prospective and retrospective duration judgments.
• Applying event segmentation theory to understand memory reconstruction.
• Presenting the Neuroenergetic Constraint Model.

Main Results:

• Long-interval temporal compression in aging is linked to memory reconstruction, not altered timekeeping.
• Experiential density (distinct memories per unit time) influences remembered duration.
• Aging-related neuroenergetic constraints may reduce experiential density, increasing temporal compression.

Conclusions:

• Experienced longevity offers a new dimension to aging research beyond lifespan and function.
• Neuroenergetic reserve is a potential biological marker for subjective time perception in aging.
• This framework links biological aging processes to the subjective structuring of lived time.