BACKGROUND:
It has been suggested that botulinum toxin A (BTX-A) treatment for frown lines can also be used as a treatment for depression. A psychological mechanism for this effect is reviewed in which paralysis of the corrugator (frown) muscles leads to less facial feedback for negative emotions. Consequently, a negative affect is harder to maintain and so the person has a more positive mood.
METHODS:
In order to test this mechanism, the mood of patients who had received BTX-A treatment for glabelar frown lines was measured and compared with patients who had received other cosmetic treatments.
RESULTS:
The BTX-A-treated patients showed significantly less negative mood.
CONCLUSION:
The results support the facial feedback view that frowning can make one unhappier. Treatments that prevent frowning correlate with reduced negative mood.