Sorry, I didn't recognise you!

To all those people I know and have inadvertently ignored, overlooked or simply not recognised, I offer my apologies and this explanation. Prosopagnosia.

A little while ago I was reading a magazine, and (metaphorically speaking) a little light went on in my mind and a lot of things made a lot more sense. It seems I have a clearly definable lower than normal ability to recognise faces.

I see faces as clearly as I see anything else. (The term face blind is sometimes used but is misleading). I can do a reasonable job at recognising people in photographs - though perhaps not as well as most people. But matching a memory to a face in front of me? That's where I can have problems. People I know well and meet often, I can usually identify - unless they happen to be in an unusual place. Or are wearing a different style of clothing. Or have changed their hair style or colour. It helps if they are not average size, too!

So there I was reading this article (New Scientist, March 2005) when I realised that it was talking about me. The symptoms fitted. More importantly, the experiences described matched mine. So now I know what I am dealing with. In the time since then, I have realised that social problems I have experienced in the past (and present...) were perhaps caused by prosopagnosia: insecurity when meeting people, near panic when expected to meet recent acquaintances. Lest any should think this trivial, or - perish the thought - amusing, I would offer the following situations as samples

meeting existing friends when I started school - and having to have them pointed out
looking for the same pretty girl at the school dance lessons - and relying on her to recognise me
not recognising my parents in a crowd
being utterly confused at not recognising the woman I was later to marry when she turned up with a completely different hair do
relying on my children to recognise me when I had to collect them from school, parties or scout meetings (especially tricky because of the uniforms)

I have been left with a great reluctance to attend social events with more than a few people but less than crowd to hide in. Large groups where it is difficult for me to recognise folk but I am expected to are especially embarrassing. Gatherings where people are likely to be presenting themselves - in manner, style of dress etc. - in a way not familiar to me cause me anxiety; generally far more than can be compensated for by the event itself.

So how do I manage, you might be wondering? So am I. Since realising the problem, I have given this some thought and the answer has to be that in some ways I don't. However, there are a few things that do help

Voice - I can identify by voice most people I know
Context - geographical: if people are near my home, they might be neighbours
Size - anything away from average helps, up, down or sideways
Fixed features - cars or scars, rings on fingers or in noses
Being recognised - that's a relief! Now, start talking, and I'll join in...

I have found a few pages on the web that make mention of prosopagnosia. None use the word prosopagnostic though, which is a bit sad. They prefer the word prosopagnosic. Either way, the root word is agnosia which means not recognising, or not knowing. Some of the pages that say something meaningful to me are

The New Scientist article that enlightened me
Glenn Alperin's page about severe prosopagnosia.
When faces fade is an article on the "Mind Hacks" web site
Bill Choisser's very readable prosopagnosia web-book
A newer article by Caroline Williams in New Scientist, issue 2579 (24th November 2006) which amongst other things sugests up to 2% of people might be affected. I feel more normal already!