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Adults often complain that time passes increasingly faster as they get older. We remember the feeling of near-eternity while living through the summer break as teenagers. As adults we are frightened for a moment when we realize that it is again Christmas, the past year has passed again so quickly. The notion that time even “passes increasingly quickly as we grow older” is indeed common knowledge, everyone talks about this phenomenon.
While this notion is generally accepted, empirical evidence has only accumulated over the last decade. In a study Sandra Lehnhoff and I conducted, we found that 500 individuals between the ages of 14 and 94 years indeed showed the expected age effect (read a discussion of results in an earlier Psychology Today blog by Nancy Darling): The older the participants of the study, the more likely they reported time to pass quickly. Especially the period of time covering the last 10 years was sensitive to age differences. The question of “how fast the last 10 years passed” captured this age effect in several following studies–important in the era of irreproducible results in Psychology. We had initially asked people living in German and Austrian. Our results were then replicated by a separate study group with participants from the Netherlands, New Zealand, and Japan. One can say that for individuals in industrialized nations the last 10 years of a life speed up as one grows older.
How to explain this “fact” of the human condition? One convincing answer lies in how memory works (see Douwe Draaisma’s excellent book concerning this idea). How do we perceive time when we look back at periods of life? ‘Memory content’ is the key to an answer. The more changing experiences we have, the longer subjective duration in retrospect. We all know this effect very well. For example, a weekend spent with our usual routines at home passes very quickly. In contrast, a weekend when we travel to a new place and explore it with a good friend lasts subjectively much longer. That is so for two intertwined reasons. First, we can recall many different and novel experiences. This “memory load” expands subjective duration. Second, because we were open for new experiences (increased attention) in a joyful context (heightened affect) memory formation is enhanced. We were literally “open” for novel experiences. Back to work on Monday morning we will have the impression of a really long weekend.
This memory explanation can in principal also be applied to longer periods of life. In childhood, adolescence and young adulthood, life is full of “first times”. Seen from a developmental perspective, on a daily basis one learns many new things. During these developmental periods we are predisposed to learn and memorize. Each year of a child is a completely new year: biologically, psychologically. Eventually, we leave school and the parents; we move to another city; we find a partner; we start a long-term job; children are born … memories of deep significance accumulate. However, what creeps in slowly over the course of the years? Routine. Even if we change jobs every other year, spend our holidays in new places, the experience of novelty, which we had when we were young, will not come back. The first kiss, the first time abroad without the parents, the first money earned … those memories have a special status in our lives. That is, when we grow older, fewer events of significance are experienced and stored in memory. As a result subjective time speeds up, at least in theory. That is to say, to date there is still no direct empirical evidence for this memory-routine effect as explanation for the feeling that time speeds up with increasing age. It is a well-informed hypothesis based on empirical evidence with shorter time intervals in the minutes to hours range.
A study which we published in 2015 at least shows that one personality trait, which can be discussed as linked to memory, modulates subjective time over the life periods: the ability of ‘emotion regulation’. Emotion regulation refers to the competence to actively modulate affective states. It is known that individuals who are able to regulate their emotions are less anxious and depressed, they are less stressed out in daily life, and they report greater life satisfaction and self-esteem. Our study now shows that those individuals also experience the last 10 years of their life to pass relatively slower than others who are less capable of this emotional self-control. And this finding can be linked to the discussed memory effect on time. We suggest that people who can actively regulate their emotions have more nuanced, fine grained experiences at a given moment which are then stored in long-term memory. During affective self-regulation one is more aware of what is happening and one feels a sense of agency. The ability to actively cope with one’s emotions, as opposed to a mere reactive sensibility, would lead to an intensified experience which, when looking back over a period of life, would lead to more events retrieved from memory–thus expanding subjective time in retrospect.
We nearly ended here on a melancholic note. It is probably true that life cannot be experienced with the same freshness we felt when we were much younger. That is what ‘experience’ means: losing the sense of novelty. Increasing one’s experience is an important goal in many aspects of life. We do not want to have a surgeon telling us that this is her first surgery performed ever! To some extent we can of course try to actively avoid having too many routines in life. A study has shown that employees who have many work routines feel that time passes by relatively more quickly. Another way to slow down subjective time is to learn to be aware of our feelings and to actively modulate them in a way that leads to more life satisfaction. This is a key to a richer emotional life and at the same time to a subjectively longer life.
