isual information provides data about the position and movement of the head with respect to objects and serves as a source of reference for the proper perception of verticality. It also plays a specific role in postural control by modifying the efficiency of the vestibular and proprioceptive responses. Aims. Our aim was to determine how visual information interacts with the symptoms of patients with vertigo, dizziness or instability and to find out the degree of disability it produces. Patients and methods. A study was conducted in 200 patients who had visited because of dizziness, vertigo, instability or loss of balance. We analysed the aspects related to the clinical symptoms of the patients. First, we examined the influence visual stimuli have on the symptoms of vestibular disease itself and their repercussions on the situation between crises. Second, the degree of disability was evaluated on the specific DHI (Dizziness Handicap Inventory) questionnaire. Results. As regards the influence exerted by visual stimulation on the main symptoms, 77.5% reported that it had no effect and 21% said that it made them worse. With regard to the influence of visual stimulation during the intercritical period, it was of no relevance in 53.5% of patients, 26.5% were unaffected, it had an exacerbating effect in 4% and in 7.5% it induced it. Different disorders were observed depending on the type of disease suffered by the patient, and disability was greater according to the influence exerted by the visual factor. Conclusions. Postural adjustments induced by visual stimuli are capable of triggering instability with serious consequences.