The histories of three patients with spasmodic torticollis who were treated under various theoretical guises and recovered suggested a hypothetical model of spasmodic torticollis which depends upon the notion that fortuitous head movements in the direction of the torticollis, in the absence of spasm, produce anxiety, which the ensuing spasm momentarily reduces. In this way, the movement is slowly conditioned.
A patient showed skin resistance changes on head movements which were consistent with this hypothesis, and she was accordingly treated by systematic desensitization to the anxiety-provoking effects of her own head movements. The success of this treatment and the failure to demonstrate, electromyographically, the phenomenon of reactive inhibition in eight cases of spasmodic torticollis suggested that, where massed practice succeeds, its action is similar to systematic desensitization.
Meares RA. Behavior Therapy and Spasmodic Torticollis. Arch Gen Psychiatry. 1973;28(1):104-107. doi:10.1001/archpsyc.1973.01750310082013