I'd like to introduce you to a primitive bit of my brain – he's called "Dippy". Dippy lives deep inside my head. Dippy is there to always look out for me – if I survive then he survives. Dippy is actually very good at this, he's always scanning for threats and alerting me to act should he detect some kind of danger. The thing is though, my Dippy's a bit too keen as he keeps raising false alarms. Unfortunately he has – what we may politely call – severe learning difficulties. No matter how many times he is told off, he never learns and never fails to raise false alarms. Dippy's keenness is a big problem because once he sets off the alarm a few times, he doesn't know when to stop.

Dippy's over-enthusiam is a major irritation for the conscious part of my brain – let's call that part "Ross". Ross has lots of things to think about, he wants to solve problems, he likes to dream and have aspirations, he wants to help people and to work hard, he wants to live and love, but Dippy is constantly plaguing Ross with interruptions which are getting in the way of all that. As Dippy lives right next to Ross he has a special connection with Ross's imagination and every time Ross imagines something that Dippy thinks is alarming, Dippy dutifully raises an alarm loudly, very loudly.

As Dippy is so rubbish at telling the difference between real threats and false alarms, Ross feels obliged to intervene as the alarms are way too loud to tolerate. Ross thinks that it's wrong to just ignore the alarms in case one of them means something real, so Ross makes his own assessments of the level of threat. When Ross examines the alarms in detail he has to use his imagination to think of all the things that they could mean. While Ross is doing this, Dippy is still on the alert and as soon as he sees the activity in Ross's imagination he sets off another alarm. It's then natural for Ross to think that the alarms really must mean something very dangerous as they're so loud and so persistent. Ross then looks even more closely at the alarms as he has to be sure.

When Dippy behaves in useful way he does a great job at forcing Ross to jump out of the way of a speeding car. In order to do this effectively, Dippy MUST be obeyed WITHOUT FAIL. Dippy might be a bit stupid, but he really does know how to scare the hell out of Ross! Otherwise Ross – and all fellow human beings – would all fail to act when a wolf appears and we would all be lunch. Dippy has evolved these special powers for survival.

When Dippy constantly sends false alarms, this is part of a condition called OCD (obsessive compulsive disorder). Some people confuse OCD with a similar sounding, but completely different, condition called OCPD (obsessive compulsive personality disorder), and most people don't really know what OCD really is. In truth, OCD is one of the most frightening, distressing, and disabling conditions anyone can experience. Introducing Dippy to you is just my way of describing the mechanics of OCD. The human experience of OCD, as the thoughts go round and round and as the alarm gets louder and louder, is very very emotive. For instance:

These are just some of the catastrophic (mis)interpretations that OCD gives its victims due to all this signals going round in their heads. If you know me and think that I'm not interested in engaging with you, or if you find me rather withdrawn or not up to standard, it's not your fault (nor mine), it's my Dippy causing me disabling distress.