In 1995, a television program in Japan reported that a man decided to wear a wire hanger around his head while he was studying (as you do) and found that his head involuntarily rotated. It doesn’t sound real, does it? Or maybe it was a one-off occasion? But there have now been a few peer-reviewed papers suggesting that this phenomenon exists and might actually affect the majority of people.
It is known as the "hanger reflex" (HR) and occurs when the pressure of a hanger mounted on the head causes involuntary motion. In 2015, a study delved into the HR even further, taking 120 healthy Japanese adults, placing a wire clothes hanger on their heads, and recording the results.
If you want to know the specifics, the longer side of the hanger was attached over the participant’s frontotemporal regions of the head, and 95.8 percent of the subjects felt a head rotation sensation, while only five (4.2 percent) were non-responders. In the study, 85.4 percent observed a rotation in the direction that coincided with the side compressed by the hanger. There were no differences between the genders.
In 2014, scientists investigated the phenomenon by creating a head rotation interface using the HR. This basically means they created a "hat" that could apply pressure at various points. Using it, they discovered the "sweet spots" that cause the HR: the anterior and posterior temporal regions. They then used actuators (machine movers) connected to a microcomputer to press the head from four different points in a very hand-made-looking hat, similar to what Louis Tully wore in Ghostbusters.
The best application that the scientists found for the device was navigation. The user can input their destination into an app and walk around freely, and when they are required to turn the HR interface would gently put pressure on their head to turn their face in the correct direction. This head rotation is the natural motion proceeding a turn and is, therefore, a more intuitive walking navigation device than some earlier models (yes there were a few iterations of this).
Scientists have also researched other applications of the HR device, including as a treatment for cervical dystonia (CD). CD is when patients have an involuntary neck contraction that can cause the head to twist or turn to one side. There are a wide variety of treatments for this, including spinal cord and electrical stimulation, but some of these treatments can be invasive and costly. The device was applied to the CD patients for 30 minutes a day for three months and, ultimately, it improved atypical rotation in patients. All the study participants expressed the desire to continue using the device.
Another paper described a woman who had her head turned to the right for 5 years. When she wore the HR device on her head, she could turn her head easily to the left. Three months later, her head movement problems had almost completely resolved even without wearing the device, and she saw no reoccurrence after nine months.
So, this weird reflex could literally and figuratively be turning heads towards non-invasive treatments for neurological and dystonia disorders.