Applying mild electrical stimulation to the brain temporarily removed a perceptual bias linked to the sexual objectification of women, in the first study of its kind.
People are much better at recognising faces and bodies when they are upright than when they are upside down - a sign that we are seeing a person - whereas for objects it makes far less difference. Laboratory studies have found that, in both male and female viewers, this upright advantage shrinks for sexualised images of women but not men, suggesting they are processed more like objects.
A University of Exeter study of 76 students found that applying a mild electric current to the scalp for ten minutes improved how well participants recognised upright sexualised images of women, compared with a placebo, and removed a difference in the way images of women and men were processed.
Professor Ciro Civile, of the University of Exeter, who led the study, said: "Sexual objectification means treating a person as a body to be looked at or used, rather than as a whole person. It's dehumanising and most often experienced by women."
Sexual objectification is pervasive in film, TV, social media and advertising, and has been linked to greater tolerance of harassment, as well as body shame, anxiety, eating disorders and depression. It also encourages self-objectification, where women internalise other people's view of them and come to judge themselves by their appearance and by public approval.
"Professor Civile said: "Our findings are initial evidence that the way our visual system processes sexualised images of women can be changed, at least temporarily, by mildly stimulating the brain. This was a lab study - we didn't measure attitudes or behaviour, and brain stimulation is no cure for sexism - but it gives us a new way to study how objectification works."
The new study, published in the journal Social Neuroscience, involved 54 female students and 22 male students. The researchers used the upside-down test, which measures what is known as the inversion effect.
Participants were asked to memorise images of male and female models in underwear, photographed in sexualised poses and shown both upright and upside down. They were then asked whether they recognised the models when these were mixed in with images they hadn't seen previously.
While participants carried out the task, half the group received a mild electrical current to the scalp for ten minutes, using a technique called transcranial direct current stimulation (tDCS). It involves a weak current being passed between two small electrodes resting on the scalp - one on the left side of the forehead and the other above the right eyebrow. The other half of participants were given a placebo treatment of just 30 seconds of stimulation, and neither the participants nor the experimenters knew who was in which group. The technique is widely used in research and usually causes no more than a mild tingling sensation. No adverse effects were reported in the study.
