THERE are many things I find myself ruminating over on a daily basis. Such as why on earth people would spend the equivalent to the GDP of a small country to buy concert tickets (I am looking at you, fellow Taylor Swift fans).

Or how, every so often, I suffer a bout of amnesia about what a cesspit of negativity Twitter is and open the app (only to promptly close it again feeling soiled to the deepest reaches of my soul).

But one thing I rarely give much thought to is how I might look when I’m older. Partly because I don’t give much thought to how I look now. But also, because I have always blithely adhered to the delusion that I would look much as I do in middle age, only with greyer hair and a few more wrinkles.

Then came *that* viral filter on the social media platform TikTok. If you are unfamiliar with what I’m talking about, then let me walk you through the quagmire that is “Aged”, an AI-generated depiction of how users will - allegedly - look as they grow older.

Read more: All human life is here – how I fell in love with parkrun

The filter, which overlays the face in real time, deepens wrinkles and adds sagging, as well as emphasising details such as dark circles and hyperpigmentation. The results are best described as, well, divisive.

It typically goes one of two ways: those smugly humble bragging about how amazing they look, or those gazing slack-jawed in abject horror as their entire life flashes before their eyes (chiefly every occasion you forgot to apply sunblock or did ill-advised tequila shots in a bar at 3am).

Among the most shared videos is that of a younger woman using the filter. It is accompanied with the breezy caption, “she looks so fun and full of life, I can’t wait to meet her”, in reference to how flawlessly beautiful the older version of herself appears.

Then there are those whose unflinching summaries of using “Aged” include “I look like I eat children”; “I look like I've been in ‘Spoons having a Stella at 10am”; and “I look like I s*** myself at bingo”.

I secretly hoped I’d fall into the Diane Keaton, Meryl Streep or Emma Thompson camp of growing old gracefully. And to be fair, I do look like a movie star, although according to the “Aged” filter, it is less effortlessly chic matriarch and more Gollum from Lord of the Rings after a 10-day bender through every hostelry in the Misty Mountains.

It puts me in mind of 101-year-old Rose in the film Titanic, when she catches a glimpse of herself in a hand mirror recovered from the sunken liner and laments, “the reflection has changed a bit”.

Or the walking embodiment of the Baz Luhrmann song Everybody’s Free (To Wear Sunscreen) which imparts the sage advice: “Enjoy the power and beauty of your youth. Oh, never mind … You will not understand the power and beauty of your youth until they’ve faded.”

More than one dermatologist has gone on record to say they believe the “Aged” filter is a realistic representation of how our skin and facial structures change as we grow older. Yet, others say it is unable to truly capture how variables, such as lifestyle and habits, can affect the outcome.

Read more: Sunburn and salads – how Scotland loses its mind in summer

Social commentators have rightly pointed out that the repulsion many users have felt when seeing their appearance as an older person raises myriad thorny issues about age and prejudice.

It has certainly given me plenty of food for thought about my initial reaction. Is it merely vanity or something far more unpalatable?

Perhaps a bit of both. What the “Aged” filter highlights is the deep-rooted fear that most of us float through life trying to ignore: our own mortality. The human fear of ageing is, arguably, the fear of death. Oh, and a jarring reminder that time itself is fleeting and precious.