The drizzle still hisses, and droplets plop outside the window. Inside we watch a trace on a computer monitor, mapping out a student's brain at work. It's dim and grey, and the classroom lights are on despite it being mid-morning. There's a cosy feeling in the room because nobody wishes to be outside today.

A light blinks on and off in front of the student. His eyes are closed but the light is bright enough to shine through his eyelids. The sawtoothed trace of his brain at rest becomes a much flatter line as the light blinks on, and the sawtooth pattern returns when it blinks off again. And on, and off, and on, and off, over and over the same pattern repeats on the trace. He wears a bright white cap, that I fitted to his head. It has a mass of fine wires snaking over it from electrodes recording the minute electrical charges in the skin caused by the activity in the brain below.

Low mood, causes lethargy, sapping initiative and motivation. It diminishes confidence and has a negative influence on others nearby. And it has a quality of self-reinforcement. Plently of people describe getting into an uncontrollable spiral into depression, self neglect and despair.
There's plenty about space to cause low mood, too. The isolation, monotony, lack of sleep, and many other stressors.

But if you see it coming early enough, one can take steps to prevent it from developing. And that is one of the many things that ESA is interested in. How do you see it coming? Specifically, how can we see it developing in an individual who is aboard a capsule millions of miles away, with no possibility to get back to earth for support or respite or escape, who must continue to carry out critical tasks requiring attentional focus, and co-operate with a team whose spirit could all so easily be undermined. With distrust comes a lack of communication, and with that, a very dysfunctional team.

Monitoring is the key. But monitor what? Stress hormones? Brain activity? Self-reports? Measurements of heart rate and exercise performance? We need baseline data for how these things change in people under stress of isolation and coping, and how they change in people who are under stress and don't cope with it .
Which is why I'm learning to fit the EEG cap and put someone through a programme of exercise. To take blood samples and administer computer based reaction time tasks and questionaires about how they've been feeling recently.

You may have heard of Mars 500. Six guys in a capsule in Russia for 540 days (the time for a round trip to Mars). They're doing the same sort of experiments.

Thankfully at least I will get to go outside, and see the most amazing night sky that can be seen on earth.