It was May 2006, and I had just been swimming. I was on my way from my home in Hastings to work as a revenue executive for HMRC. It was raining hard, and the visibility was terrible. I was crossing the road when a white van drove into me and I fell, hit the side of my head, and rolled under a parked car. I have no memory of it. In fact I didn’t remember anything from a year before the accident until four years afterwards; I began to work out what had happened to me from what other people told me.

I was in an induced coma for three weeks in the neurological unit attached to Haywards Heath hospital. The medical staff tried to bring me out of the coma after about 10 days, but it was too early. I’ve got no medical notes about my time in hospital, but my family and friends were there every day. My coma was marked grade 3 in the Glasgow Coma Scale: the deepest one you can be in but still be alive; luckily I didn’t need brain surgery.

When I started coming round I was moved to my local hospital. The strangest thing was that the first words I spoke were French. A friend asked the nurses whether he should speak to me in French; they thought it was a good idea, to encourage communication. So he would ask me a question in French, and I would reply in fluent French. No one knew why, but I had done both German and French at O-level almost 30 years earlier. After a while, the doctors decided speaking French was not helping me, because I’m English. So posters were put on the wall asking people not to speak in French.

Before my coma I’d never heard of foreign accent syndrome, which can occur when people wake up from a coma and their speech is affected; people sometimes perceive it as a foreign accent. What happened to me is different, because I really was speaking French, and not just for a few seconds – for two weeks.

I still don’t know why. I’ve never had any desire to visit France, although there has always been talk in our family about our French ancestry, which can be traced right back to the grandparents of Cardinal Richelieu.

Six months before the accident, I had directed an opera by Gilbert and Sullivan and two of my friends came to the hospital to play the overture from Iolanthe, hoping it would inspire me to become fully conscious. My heart raced when the music was played and went back to normal when it stopped. There was a book for visitors to make notes – for example, when I said an English word, or smiled. My father used to sing nursery rhymes to me and was really pleased when he sang, “1, 2, 3, 4, 5” and I replied, “Once I caught a fish alive.” That was quite a milestone and a relief that I was speaking English.

I was in my local hospital for a couple of months and then moved to a brain rehabilitation centre where I stayed for about a year. I still wasn’t making much sense, and had to relearn everything, including how to breathe on my own.

I don’t remember this period at all: it’s a blank. Friends tell me what I used to say and do, such as saying numbers and doing sums out loud, but it really does sound as if they’re talking about someone else.

I eventually went home and was looked after by carers; I have never married and don’t have children. I don’t remember learning to read again, but I do remember being attracted to books I had read as a child, such as Charlotte’s Web. It was almost like trying to start life again.

Before the accident I had run five half-marathons, and as I was recovering, I couldn’t bear to see people jogging. I walk with a stick now, and I can’t use steps unless there’s a rail to hang on to. I will never be 100% back to normal because I have diffuse axonal brain damage, which affects spatial awareness. When I am walking, my feet don’t know when they are going to hit the ground.

Three years ago, I heard Esther Rantzen talking on the radio about her charity The Silver Line, which matches volunteers with lonely and isolated older people, and they talk on the phone once a week. I rang up straight away and was assigned a “friend” who is 75. The role has changed my life and helped me to feel useful and normal again. It’s lucky I didn’t lose my ability to speak English, or we would never have been able to communicate.

• As told to Kate Morris

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