Visual impairment Due to poor development of macula or confusion caused by tremor is not conducive to macula for gaze, gaze reflex cannot be developed. Object motion sensation A sense of turbulence when looking at external objects, vertigo, nausea, vomiting, and often perceiving motionless objects as constantly moving back and forth. Diplopia Central nystagmus mostly has nystagmus diplopia. Compensatory head position Head-turning nystagmus is often associated with congenital cataracts or albinism, etc. There is significant visual impairment, and the form of nystagmus is mostly oscillatory, horizontal nystagmus of equal speed. Acquired nystagmus is often vertical or rotational. Central nystagmus Nystagmus caused by inflammation, tumor, degeneration, trauma, or vascular disease in the vestibule or its connection pathway with the cerebellar stem, mostly impulsive or horizontal nystagmus, usually without vertigo symptoms, but sometimes with tremulous diplopia. Congenital idiopathic nystagmus is mostly impulsive or horizontal, more pronounced when gazing, without obvious organic pathology. Visual acuity loss is mostly due to object tremor, so tremor reduction can occur in a certain area in the slow-phase direction, i.e., resting eye position can significantly improve visual acuity here.