We tend to link Seasonal Affective Disorder solely to lack of light, but it’s worth considering that an excess of light at the wrong time of day can do a good deal to disrupt ones circadian rhythms. Thanks to electric lighting, we run our lives at maximum brightness until it’s time for bed at eleven or twelve, and expect our brains to obediently switch off after a day of stimulation.

I’m not ready to give up my precious tiny slice of personal time on the laptop once the day’s work is done, but perhaps there’s a way to have my cake and eat it too: An application called ‘F.Lux’ from stereopsis.com takes control of your computer screen’s colour profile. During the day, the screen is its normal sharp, blueis white colour. As the night proceeds, F.Lux gradualy adjusts the tones and brightness of your monitor, making the light softer and yellower, and less glaring.

The idea behind the program is that the harsh blue-white light tells our brain that it’s daytime and that it accordingly tries to stay awake and alert. Then, when it’s time for sleep…

So does it work? I use it, and while I initially found the nighttime screen a bit disconcerting, I got used to it after a couple of minutes. When the software is running there’s a little control panel which you can click to momentarily see what the screen would like if left to its own devices. Whenever I try this I end up doing a good imitation of Count Dracula, flinching from the harsh sunlight and drawing my cape across my face. Then I go down to the crypt and lie in a box of earth until I feel better.

So maybe it does something. And it’s free. Did I mention that? Free free free. And it runs on pretty much everything. You may as well give it a go.

We’re used to hearing about light therapy as a treatment for Seasonal Affective Disorder, and the consensus seems to be that it does do some good. We tend to think of the light as entering via our eyes in the traditional manner though, and there seem to be some other options:

Valkee have started producing SAD lighting treatments which are delivered via the ear canals, directly into the brain. Users wear what looks like an mp3 player (available in black and white and rather pretending to be an iPod) with a pair of earbuds which shine bright white light instead of playing sounds. Their idea is nothing to do with the ears themsleves – the ear canals just provide a simple way of getting light onto the surface of the brain, which they claim is photosensitive.

I suppose if you’re wearing them on public transport and someone asks you what you’re listening to, you can always say it’s The Velvet Underground’ s _White Light White Heat_.

Is the idea flakey? Rather. Is it real and effective? I have no idea as yet – it will be interesting to see what eventually comes out of this – whether it will be remembered as just another piece of quackery or the birth of an effective treatment. It has been written up in a peer reviewed journal, but as the following link indicates, perhaps not all that peer reviewed: http://www.arcticstartup.com/2012/02/14/valkee-peer-reviewed.

One tangentially interesting bit of research – there’s been some talk about light absorbed through the skin affecting haemoglobin and indirectly affecting seasonal affective disorder. We talk about it here.

In the meantime perhaps you should do what my wife suggested when I told her about this research, and stick some Christmas tree lights in your ears

Just a quick note this time – this one’s a fairly old article, and from a quick look at this researcher’s work it looks like he may no longer be pursuing this exact line.

Light therapy for Seasonal Affective Disorder is normally associated with absorbing bright light through the eyes. This article seems to at least hint at light transmission into the skin – for skin is far from completely opaque, as anyone who’s tried to make a realistic skin texture in 3d computer graphics can testify – having an affect on winter blues. The haemoglobin in our blood is light sensitive, and can act as a messenger to our brain, according to Dan Oren of Yale University.

http://www.sciencedaily.com/releases/1998/01/980129074137.htm

It makes me think of pictures I’ve seen of brave or masochistic russians sunbathing in moments of midwinter sunshine – perhaps there’s more to it than bloody mindedness.

Or “We are not alone”

Rats and mice are valuable experimental animals, as they share so much biologically with us – but they’re not particularly good subjects for studying Seasonal Affective Depression. Mice are nocturnal, and do most of their running around at times when their melatonin levels are high – when we’re safely asleep. Accordingly, two researchers, Prof. Noga Kronfeld-Schor of Tel Aviv University and, Prof. Haim Einat of the University of Minnesota decided to look at using a diurnal experimental subject, the Fat Sand Rat (Psammomys obesus) a relative of the gerbil native to the middle east and north africa.

They found the rats would develop symptoms matching Winter Blues when given simulated shorter winter , and better yet would, respond to light therapy in a way simular to human sufferers. This doesn’t mean we’re any closer to effective treatments, but it is good to have an animal subject which behaves analogously to humans.

One important point to take away is that this helps us eliminate the possibility of light therapy’s efficacy being due to the placebo effect, as the sand rats are unlikely to have been able to divine the researcher’s intentions. There is, of course, the possibility that the sand rats are just depressed because people keep calling them fat.

Tal Ashkenazy, Haim Einat, Noga Kronfeld-Schor. We are in the dark here: induction of depression- and anxiety-like behaviours in the diurnal fat sand rat, by short daylight or melatonin injections. The International Journal of Neuropsychopharmacology, 2008; 12 (01): 83 DOI: 10.1017/S1461145708009115

http://www.sciencedaily.com/releases/2010/11/101108140921.htm

When I was a kid I loved to watch Doctor Who (For that matter, I still love it, but I’m not terrified of it anymore) and follow The Doctor on his travels through the universe, encountering robots, aliens, time travellers and an endless sucession of alien planets that look like the same disused gravel quarry.

In one of these, The Ark in Space we meet a particularly nasty insectoid hive-mind which is gobbling up the sleeping crew of a long haul spaceship, one by one. As each crew member is posessed by the aliens, they say “Contact has been made”, to which the already-posessed crewmember who has awoken them replies “The nucleus must be conserved”.

Now, the suprachiasmatic nucleus is a little blob around the size of a pea, hidden somewehere deep in our brains. Among its task is the regulation of our bodily clocks. When we’re exposed to light, the suprachiasmatic nucleus acts to suppress the production of melatonin. When there’s not enough light, melatonin production is not controlled properly, and gloomy sluggish slothful winter blues result. Or that’s one theory of many, anyway. More on that later, but for the moment I just wanted to meditate on how every time I hear the phrase “suprachiasmatic nucleus” I see a giant alien insect saying “The nucleus must be conserved!”.

As indeed it must.

It used to be that around midwinter I’d start obsessively checking day length calculators on the net, seeing how many seconds longer that today tomorrow would be, and trying to work out when my most important day of the year, “Minute Day” would be. (Minute day – or so I’ve defined it – is the first day that’s a minute longer than the day before, thus indicating that spring will come again, and the world isn’t ending.)

In the end, I did the sensible thing, and wrote myself a little gadget which would show the length of the days for an entire year, from six months in the past to six months in the future in one glance. Now it’s your turn to play with it.

You can get to it by going here or by clicking on the “Sunrise Calculator” link at the top of the page. (You’ll need Adobe Flash installed.)

The first time you use it, it will be set for Melbourne, Australia, where I live. You can change this to where you live by clicking on the “My Location” tab on the program, and providing you’ve got cookies turned on, the program should remember this.

This site aims to serve as a reference for information about Seasonal Affective Depression, aka SAD or Winter Blues. I’ll be discussing what it is, how it’s treated, and how well those treatments work, and trying to keep up with articles in the scientific literature.

Topics I’ll be discussing include:

• light therapy
• melatonin
• omega-3s
• vitamin D
• meditation
• exercise

Welcome, and I hope this site proves useful to you.