Botox injections to stave off creases made by frowning and a furrowed brow may help alleviate some symptoms of depression, a study suggests.
Botox is a common beauty treatment to alleviate wrinkles by paralysing facial muscles with the toxin from the bacteria Clostridium botulinum. It is also used for non-superficial medical needs, such as to prevent excessive sweating, incontinence and migraines.
But previous studies have shown that botox can also have the beneficial side-effect of improving a person’s mood and helping with some symptoms of depression.
Researchers studied how botox treatments to the forehead area impact on the emotional state of 45 women with borderline personality disorder (BPD), a condition which manifests as impulsivity and prominent negative emotions.
The study's senior author, Dr Axel Wollmer of Semmelweis University, said: "This is one of the most common personality disorders with symptoms of emotional instability and impulsive behaviour.
"Patients suffering from BPD experience an excess of negative emotions like anger and fear.
"Our hypothesis was that relaxing the muscles in the forehead with botox will interrupt a feedback loop between the face and the brain and thereby reduce these negative emotions."
Botox could play a role in treating depression
During the study, the women received either botox or acupuncture and were quizzed both before and afterwards about their emotional state.
This task involved them trying to control their reactions to certain cues as they saw pictures of faces with different emotional expressions presented to them on a computer screen, while researchers monitored their brain activity.
MRI scans of the injected patients showed that when people had botox to the forehead they had less activity in some regions of the brain which are involved with emotional processing.
“This study provides the first evidence that glabellar botox injections may modify central neurobiological and behavioural aspects of BPD,” the researchers write in their paper, published in the journal Scientific Reports.
Dr Wollmer found that people who had botox had altered brain activity which was visible on the MRI scans.
"The images showed a reduction in the activity of the amygdala in response to emotional stimuli, which is often exaggerated in BPD patients,” Dr Wollmer said.
"The World Health Organization estimates that the number of people suffering from depression is approximately 280 million.
"Established treatments such as psychotherapy or antidepressants don't work sufficiently for about one third of the patients so there is a need to develop novel treatment options, and this is where botox injections could have a role."
Injections reduced patients' impulsive behaviour
The researchers also noticed that botox reduced the patients' impulsive behaviour and it corresponded with the activation of prefrontal areas in the brain which are involved in inhibitory control.
In the study, the researchers posit that botox improves one’s emotional state by breaking what they call the “facial feedback loop”.
This is a theory which dates back to the time of Charles Darwin and states that pulling a particular facial expression, such as frowning, can strengthen certain emotions.
For example, if a person was to frown in response to a negative stimulus, it may help deepen negative feelings of sadness or depression. By stopping a person from being able to frown with botox, the researchers of the new study believe, this may snap the vicious cycle.
Previous research has suggested that emotions expressed on the face affect our mental state.
Negative emotions such as anger, sadness, or fear often generate vertical wrinkles between the eyebrows.
When treated with botox the underlying muscles are paralysed in this area and it is understood that this reduces the intensity of those emotions.