Last night I dreamed that champignons are dangerous. That’s right, newsflash.

Now, before you inflict your kindness by sending me interpretations of my dream please realise that I’ve heard of Freud and Jung, and that I have no particular need to be analysed.

What I found most interesting about my dream was the quality of images and story I was experiencing. It was all fully believable. It was realistic to an extend that it took a second or two after waking up to realise that the mushroom was an illusion, and that my mind got tricked.

This reminded me of the mysterious ways in which our brain functions, and how we often see what we want to see or don’t see what we don’t want to see.

Those of you who have studied photography, or other forms of art and design, will be aware that it is our brain that sees, not the eye. The eye is a highly developed arrangement of lens and sensor that allows for signals to be send to the brain. There the information is interpreted and assembled in a rather complex process involving a range of areas within our brain.

The result is a stream of images that is a fairly good interpretation of our actual surroundings. But it is not perfect, and the brain is working hard to keep our world relatively steady and balanced. In the process some information – colour for example – may be radically misinterpreted to ensure that we do not suffer from visual overstimulation.

I have no idea how the processes of dreaming and seeing are connected, but I do know that our interpretation of what we see is often not consistent with what is in front of us. Sometimes the brain seems to make things up even when we are awake. So it comes as no surprise that it also does so when we sleep.

I often do eye/mind exercises when working with 1st year photography students. The tricks are intended to show students how fallible our senses can be, and how this knowledge can be of importance when designing with colour, tone and perspective.

Here’s a little gem for you that fools just about every photography student. It often takes them a little time to accept that they’ve just been fooled by their brain. If you have Photoshop or know how to find your computer OS colour meter, you will find that squares A and B are identical in tone. But most people – no matter how hard they look – won’t see it that way.