Important research into the nature of Tourette’s Syndrome, a neurological syndrome that plagues sufferers with tics and compulsions: turns out that you can inflict similar tics upon neurotypical individuals via magnetic pulse:
Jennifer Finis of Heinrich Heine University in Düsseldorf, Germany, and her colleagues suspected that a type of Tourette’s tic called echophenomena, which involves mimicking other’s movements, may be caused by over-excitation of the supplementary motor area (SMA) – a brain region involved in the initiation of movement.
To investigate further, her team used a non-invasive technique called repetitive transcranial magnetic stimulation (rTMS), which involves delivering brief but strong magnetic pulses to the scalp. By changing the frequency of rTMS, the stimulation could either inhibit or excite the SMA.
Thirty seconds after rTMS, 30 volunteers were shown video clips of someone making a spontaneous movement. Those who’d had their SMA excited were three times as likely to imitate the kind of behaviour they saw in the clips than those who’d had it suppressed.