I am studying for my finals at the moment. Every year, at around this time, I suffer an unpleasant bout of winter blues. I am stuck as to how to solve this habitual problem, although I have started to take St John's wort, which my GP recommended.

I don't have such a low mood as I did at this time last year, but my concentration is shot to pieces. I can only read at an extremely slow pace and I find writing essays even more onerous. Although I don't have trouble sleeping at night, I have been tempted to nap through my afternoon lectures. This is in total contrast to other times in the year, when I am able to give my work my full attention and to enjoy it too.

Now, I sit at my desk for hours, reading and re-reading the same paragraph but unable to take it in. My final exams are coming up in a few months and I am anxious that the time I am wasting now will seriously impact on my results. This leads me to worry about failing to find a job after I graduate. This fretting, in turn, interferes with my ability to work. I am reluctant to sit down at a desk and open my books, such is my fear of failing to be able to work, although I try nevertheless.

I need to import my "summer concentration levels" into winter, but short of emigrating to warmer climes, I don't know what to do. Can anyone give me some advice?

Compensate for the darkness

I live inside the Arctic Circle and we lose the sun altogether for two months in the winter. Here are some strategies that work for me: cod liver oil helps to replenish the vitamin D your body isn't getting from the sun in winter; eating "slow-release", low-GI foods will help to sustain your energy levels and get lots of protein in your diet too; go for a half-hour walk in the middle of the day to maximise the beneficial effect of what daylight there is; schedule a daily power nap if you feel you need extra sleep; and if you are finding it hard to work at your desk, take yourself to a cafe and scribble notes over (strategic) coffee and cake in a relaxed, non-threatening environment. I know these are tiny recommendations and they don't provide a cure-all, but you should notice a change for the better if you implement these alongside whatever your doctor recommends.

I would suggest you inform your tutor that you have this problem and have been to see your doctor about it. Far better that they should know now than hear about it for the first time during or after your finals - they will want to support you.
MJ, Tromsø, Norway

Don't push yourself

You're allowing long-term fears about your future to intrude on your normal thought processes, so rather than thinking, "I'll never get a job when I graduate," try to focus on one small, manageable task at a time. There's no point in sitting at your desk for hours in growing panic; instead, set yourself an achievable target, such as reading one chapter of a book, and then go for a walk and think about it.

Know when to stop pushing yourself too - schedule alternative activities for yourself and don't feel guilty about doing something other than work. Going for a run or meeting a friend may actually help you feel refreshed and more able to study.

Don't pile on the pressure further by blaming yourself - it's very common to feel this way. And it's not your fault.
LA, Oxford

Nobody is energetic all the time

Check your university's guidelines on support for students affected by depression, and talk to the learning support centre or equivalent; your tutors will only be able to help you if they are aware of your difficulties.

Work won't be nearly as much of a nightmare as you imagine. The idea of moving to warmer climes - at least in the winter - might actually be a good one, depending on your chosen career. I travel a lot for my job and I can't believe how much more energised I am in countries with decent winter light levels. If that's not what you want, a lightbox from the NHS can be helpful, although they don't work for everyone. Don't beat yourself up about "wasting time" - nobody is energetic all the time, all year round, even if there's a tendency to pretend otherwise. Practise deciding which tasks really are "urgent and important", and drop others during difficult periods. Sometimes it can help to project a reasonably confident exterior and to highlight the successful work that you do get done.

It's a good idea to take your annual work rhythms into account when planning your career and it's good that you are thinking about this in advance, but you'll probably find that it's a lot easier to manage these in a work environment than it has been during your undergraduate studies.
Name and address withheld

What the expert thinks

It sounds as though you're suffering from seasonal affective disorder (Sad), although the annual onset of your symptoms occurs later than for most people. The majority will first experience symptoms sometime between September and November.

The symptoms of Sad are similar to those of depression: weepiness; feelings of hopelessness and constant tiredness; sleep and/or appetite disturbances; anxiety or moodiness; and inability to concentrate or make decisions. The primary difference between the two conditions is that Sad is season-specific and recurs regularly, whereas depression can strike at any time.

Once you have an accurate diagnosis, you can create a treatment package with your GP that is right for you. It is vital that you do this, because treatments for most psychological conditions are often either too general - they target more symptoms than the patient shows, leaving her feeling overmedicated - or over specific - so they work on only a few of the symptoms. Discuss the possibilities with your doctor so that you can choose the treatments that target your symptoms.

For Sad, as for depression, the most frequently prescribed treatments are antidepressants and/or psychotherapy - in particular, cognitive therapy. Light therapy is said to help up to 80% of Sad sufferers. This is administered through light boxes, light visors or dawn simulators, or by being in natural light for at least 30 minutes every day. Other possible treatments include gentle aerobic exercise, yoga, deep breathing, St John's wort, and a reduction in stress.

It's important that you get professional help, because one treatment may interact unfavourably with another. For example, St John's wort can inhibit the efficacy of some antidepressants, and it can also make you overly sensitive to light, thus making light therapy problematic. The best information about Sad can be found in the Mind guide to Sad at mind.org.uk. Two other helpful factsheets can be found on sada.org.uk and bupa.co.uk.

Right now you also need suggestions to help you concentrate. Sad is only partly responsible for this symptom - your own catastrophic thinking (ie leaping to the worst conclusion about what may happen) is also preventing you absorbing new material. If instead of sitting at a desk, you take some steady aerobic exercise while you learn, you'll find it easier to absorb new material. You'll be producing more endorphins, which will make you less likely to feel anxious or experience negative thoughts that interfere with your concentration.

Try this. Record the material you need to memorise on to your iPod. The act of speaking aloud in itself will familiarise you with the material. Then go out for a walk, or use a cardio machine, and listen repeatedly to the information you've recorded. You needn't "try" to learn - because you organised the material yourself and you'll be hearing the information in your own voice, you'll naturally pay attention. Try to write an essay on the subject you have been listening to soon afterwards. You'll be surprised by how much you can remember.
Linda Blair

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