A Point of View: The upside of losing one's memory

In middle age people's brains can start to slow down - a process that it is both terrifying and enlightening, says Tom Shakespeare.

Several senior moments have featured in the news over recent months. At the beginning of February, Ed Balls forgot the name of Bill Thomas, his business ally. A few weeks later, Green party leader Natalie Bennett had a terrible time remembering her party's policies when she was interviewed by Nick Ferrari on LBC. And I bet Ed Miliband hopes that we've forgotten that he forgot to mention the economy in his Labour Party conference speech last autumn. I have every sympathy for these politicians, because I am almost exactly the same age as they are, and I can't remember a darned thing.

I've always been absent-minded. In my 30s, I'd regularly park my car in town for the evening and then forget where I'd left it. It was not unusual for me to forget what I'd been doing the day before. And I've often had trouble putting a name to a face.

But I've also been good at multi-tasking and my general knowledge was once good enough for me to captain my college's University Challenge team. There was even a time when I could hold my own in a political debate.

Not now. Any childhood dream of becoming an MP is now firmly behind me because I would have no hope of remembering faces, statistics or possibly even policies. Not only do I have galloping nominal aphasia - the inability to remember names - I'm also alarmed by the erosion of my cognitive powers, full stop.

Previously, if I forgot something, I'd remember having known it. Now it's as if I never knew. I always used to pride myself on being punctual to meetings. Now I spend my time apologising to people who I've stood up due to completely forgetting appointments. My partner can tell me something, only to have to repeat herself 10 minutes later. That thing when you go into a room and forget what you're doing there? I do that too.

Ed Balls and Natalie Bennett have both had 'senior moments'

There are advantages. I can re-read the same book multiple times, and still be surprised by the ending. But I feel sad that I'm often not quite sure who it is that I am talking to at a party. And it can be risky, for example when I forget, after a few minutes, whether I have just taken my regular pain medications or not.

My difficulties may not only be the effects of age. When people approach 50, their career pressures are likely to escalate, even if they aren't a leading politician. Those high stress levels are damaging to learning and memory. Late middle age sees a collision between ever-increasing workloads, with multiple projects and responsibilities and deadlines and demands - and diminishing cognitive powers. We also have the internet and email and social media which conspire to destroy our concentration. As a result, to quote my friend Harry, my brain is like an overflowing sieve. I know I'm not alone. When I talk to my contemporaries, they're all worrying about the same problems.

Which is odd. Because to look at the media, you'd think that the difficulties of getting old are only skin deep, a matter of hair transplants and boob jobs and botox, and all those other cosmetic procedures to make you look young. How shallow can people be? Why be worried about how you look, when the way you think is so much more important? Presumably it's because the wrinkles on your face are so much more obvious than what's going amiss inside your skull. But I think we're worrying about the wrong things.

Reading the scientific research, I learn that the brain starts deteriorating from the mid-20s onwards. By our 40s and 50s, it's well under way. The changes include a drop in brain volume, loss of myelin integrity, cortical thinning, impaired receptor binding and signalling, and altered concentrations of various brain metabolites. The accumulation of neuro-fibrillary tangles, something we associate with Alzheimer's, also happens in normal ageing.

I'm not certain what all of that means, but none of it sounds good.

When I went to live and work in France, I found out for myself how much harder it is to learn a new language when you are older. I now find it difficult to remember words in English, let alone French. Often, retrieving a word becomes almost impossible. I had a blind spot around the word "procrastinate" for quite a while. I just couldn't say it. Then I told myself it was crass to procrastinate and now I don't have a problem naming my bad habit.

Sadly, although the demands of work may tail off in 15 years time, the cognitive decline is only going to get worse. I can look forward to more frustrations and embarrassments and irritations. Along with my hair, that mental acuity is gone forever. Roll on anecdotage.

Psychoanalyst Hedda Bolgar was still seeing patients at the age of 102

There are things you can do about cognitive decline, apparently, and not just mnemonics, lists and reminders. I'm not quite sure how I can improve my levels of testosterone or HDL cholesterol. But exercise is certainly good for brain health, together with that Mediterranean diet that we've heard so much about, and generally eating lots of fruits and veg. The better news is that mid-life moderate drinkers have been found to be less likely to develop cognitive impairment in old age than either teetotalers or heavy drinkers. And also that now I am wealthy enough to ensure that the wine I am moderately drinking is of much better quality than the wine I previously drank to excess.

You may be asking what I am worrying about. I'm not yet 50, after all. I don't have Alzheimer's or Parkinson's or any reason to be worried about those diseases. My favourite novelist, Penelope Fitzgerald, was nearly 80 when her last and best book, The Blue Flower, was published. The philosopher Mary Midgley is still sharp as a razor, and she'll be 96 next birthday. She didn't even write a book till she was past 50. The psychoanalyst Hedda Bolgar was still seeing patients at the age of 102. William Wordsworth wrote:

And yet the wiser mind

Mourns less for what age takes away

Than what it leaves behind.

I think he meant that we should focus on the positives, and accentuate our strengths. Creativity is possible at any age. A friend who's a senior civil servant says that although he's given up trying to remember all the facts, his colleagues come to him for advice because he sees the bigger picture. Thanks to experience, he understands the patterns and trends. Wisdom is not the amount you know, it's how you see and how you interpret what you see. You're no longer distracted by the detail.

Late bloomers

• Mary Wesley - had her first novel, Jumping The Queue, published when she was 70

• Colonel Sanders - real name Harland Sanders, started his KFC empire at the age of 65. He had previously worked as farmhand, an army mule-tender and a locomotive fireman

• Fauja Singh - the 103-year-old marathon runner took part in his first marathon at the age of 89. He is thought to be the oldest marathon runner in the world

A few months ago, I returned from a lecture tour in Australia. Heavily jet-lagged, I was trying to give someone directions while we were driving around Norwich, when I suddenly felt entirely bewildered. I could not for the life of me work out where I was. It was a moment of total panic. For those 10 seconds, I realised what it must be like to suffer from dementia, and it shook me to the core.

Last week, my colleague listened to his father, behind a drawn hospital curtain, doing an Alzheimer's diagnostic test. He said that the trickiest part was when they read out a list of words but instead of asking you to repeat them they moved on to some numerical questions before asking you to list the words a moment later. He was petrified to find that he couldn't do it himself.

Good for the brain?

Once we recover from the terror of losing our marbles, realising in middle age that our own cognitive powers are already in decline should give us empathy for those ahead of us on the life curve, as well as admiration for the young. I think it's called inter-generational solidarity.

Most of us are over-identified with our brains. In the famous knowledge economy in which we are struggling to compete, we earn our precarious living by our verbal fluency, and our analytical power and above all, our memory. We pride ourselves on our sharpness and, sad to say, we look down on stupid people. All of this means that we tend to patronize older folk when they become a bit slow, and a little forgetful. But life is not just about being fast, it's also about being right.

If I was looking for advice about anything other than which smart phone to buy, I'd generally ask someone aged 80- rather than an 18-year-old. It's like when you take a photograph - there's the shutter speed to consider, but there's also the depth of field. Perspective matters.

A Point of View is broadcast on Fridays on Radio 4 at 20:50 GMT and repeated Sundays 08:50 GMT or listen on BBC iPlayer

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