We look upset because we feel distraught. Obvious?
Maybe the other way round? Does looking sad contribute to low mood?
This would have revolutionary implications for understanding the causes of depression, and indeed the treatment of mood disorders.
How often have we intuitively felt that, if someone just tried to look happier, it might have a positive impact on their mood?
Now a team of researchers lead by Axel Wollmera and Tillmann Krugerb, based at the Psychiatric Hospital of the University of Basel, Switzerland and the Department of Psychiatry, Medical School Hannover, Germany, have indeed turned conventional thinking on its head. Their research, just published in the Journal of Psychiatric Research, has found that injecting botox into the muscles most linked with low mood, produces alleviation of depression.
Injection of botulinum toxin to the glabellar region - just above the nose and between the eyes, is part of one of the most common procedures in aesthetic medicine, as the toxin inhibits the activity of the corrugator and procerus muscles in that region. This effect is used in the cosmetic treatment of 'frown lines'.
The subjects recruited for this clinical trial were suffering from long-standing low mood - on average 16 years of recurrent episodes of depression with the current episode lasting an average of almost 30 months, and they were selected as a group unconcerned with their facial appearance (they would not have picked 'botox' if given a choice).
The study, 'Facing depression with botulinum toxin: A randomised controlled trial, involved patients who had not previously benefited from standard anti-depressant prescription medication.
In Wollmera, Krugerb and colleagues' clinical trial botulinum toxin was injected just once into a specific part of the face in 15 patients, while another 15 were injected with placebo salt water. Remarkable improvements in mood were achieved after just one injection. Six weeks after a single treatment, scores on a standard depression rating scale, for botulinum toxin recipients, were reduced on average by 47.1%, while the placebo treated group experienced only a 9.2% reduction in the measurement of their depression.
This clinical trial involved the very specific choice of two particular small muscles in the face, especially associated with negative expressions, while 'botox' cosmetic treatments may target other muscles as well.
The corrugator supercilii is a narrow muscle at the corner of the eyebrow near the nose, and is responsible for pulling the eyebrows downward and towards the nose, producing vertical wrinkles of the forehead. This 'frowning' muscle and could be regarded as key in expressing distress.
The other muscle activated when we're upset is the procerus, which extends from the lower part of the nasal bone to the middle area in the forehead between the eyebrows. It pulls the skin between the eyebrows down, so it's associated with transverse forehead lines and is usually targeted during treatment or correction of wrinkles.
Since the Victorian era 'the omega sign' of depression, or omega melancholicum was well known, being the facial expression where wrinkling of the skin above the nose and between the eyebrows resembles the Greek letter omega. The 'Omega Sign' was even believed to be diagnostic of a depressive disorder.
A skin fold running obliquely from the lower outside to the upper inside on the upper eyelid is specifically named Veraguth's folds and was also assumed historically to be characteristic of depression.
Now it looks like modern medicine is rediscovering an ancient story that depression writes in the face, and, vice versa, how the face might prop up depression.
William James, a famous Professor of Psychology at Harvard University, said in 1890, "Refuse to express a passion, and it dies", referring to a 'facial feedback' hypothesis. Wollmera, Krugerb and colleagues argue this suggests strong historical support for a mutual interaction between emotions and facial muscle activity, rather than just one way traffic.
The theory here is that expressing an emotion causes you to feel that mood, not just the other way round.
To test this revolutionary idea a number of scientific studies recently aimed to alter facial expression and then investigate whether emotional experience is subsequently affected. These studies, if they are properly scientific, have to carefully manipulate facial displays of emotion in a manner that eliminates the participants' awareness that they are being asked to produce an emotional expression.
For example, one experiment involved having subjects hold a pen between their teeth (a simulation of smiling but without the subjects realising this was the point of the experiment). They found cartoons funnier. In another experiment two golf tees were attached to either side of subjects' foreheads and the participants were asked to move the two tees together (a simulation of frowning without the subjects realising they were being asked to glower). When the tees were closer together, subjects rated unpleasant photographs more negatively.
One possible implication of all these startling findings is that you may not need 'botox' to get the same anti-depressant benefits: relaxation techniques applied specifically to your facial muscles might have the same effect.
The ''motion creates emotion'' theory is also reflected in the rise of 'laughter therapy'. A recent review by Ramon Mora-Ripoll, of the Laughter Research Network in Barcelona, Spain, surveys nine scientific studies which had found significant health benefits from laughing. For example in one study of eight laughter therapy weekly sessions, a 55% reduction in pain scores; a 12% increase in functional mobility; and a 50% reduction in depression symptoms and 42% in anxiety symptoms were produced by laughter in 107 chronic pain patients, who maintained these gains at 12 month follow-up.
Mora-Ripoll's review, entitled 'Potential health beneﬁts of simulated laughter: A narrative review of the literature and recommendations for future research' published in the Academic Journal Complementary Therapies in Medicine suggests these health benefits are often being produced by 'simulated laughter' willed upon oneself, and not triggered by humour - or fun as in 'spontaneous laughter'.
Exactly why forcing yourself to laugh, just like forcibly removing frowning or a worried expression, should produce health benefits remains mysterious, but Mora-Ripoll points out that laughter itself exercises and relaxes muscles, improves respiration, stimulates circulation, decreases stress hormones, increases immune system defenses, and elevates pain threshold.
Perhaps it improves mental functioning through the release of inhibitions and promotion of sociability, and maybe frowning less and smiling more as in the botox therapy, works in similar ways.
It's possible that the botox treatment for depression was effective because a more positive facial expression improved social interaction, and this may have contributed to improved mood. Maybe looking in the mirror, and seeing they looked more cheerful, could have lead the subjects in this clinical trial to believe they were happier. This in turn, elevated mood.
However, the Wollmera, Krugerb and colleagues argue, there are many reasons a purely aesthetic beneﬁt can be excluded as the main cause of mood improvement in the botox treatment of depression. Patients in this clinical trial were not concerned about the cosmetic appearance of their frown lines. The improvement in mood did not turn on feeling better about a cosmetic improvement in appearance. For example, one participant's depression remitted with the botox treatment, but that person disliked the facial appearance it produced.
The authors conclude that their clinical trial shows facial expressions associated with depression are not just the consequences of low mood. In fact, they may be integral components of the disorder, and therefore should also be targeted.
Clinical depression is a serious and complex disorder where it's unlikely any one treatment is going to be a magic panacea. Because standard medical treatments work only in a proportion of patients, exploring other possible approaches is warranted. One in 10 of the general population suffer from clinical anxiety and depression at any one time.
So it's good news that learning to smile and laugh more, but frown less, may just be the latest scientifically validated treatment for depression.
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