внезапное решение(E.g. Mr. Kerkorian's abrupt decision to back away from Ford comes just six months after he began building his stake. Sukhopleschenko)
резкие движения(Stereotyped movements (or stereotypy) is a term used to describe physical movements that are both aimless and repetitive. These behaviors cover a wide range of movements, from the steady, rhythmic body rocking of some developmentally disabled patients to the abrupt, transient movements of people with Tourette's syndrome. VLZ_58)