Discussion
head and neck, vertiginous, nystagmus, physical disability, vertigo, dizziness, muscle rigidity, depression, respiratory deficits, hyperventilation, disability, vestibular disorders
DISORDER, MUSCLE RELAXATION, NYSTAGMUS, DISORDERS, PHYSICAL DISABILITY, VESTIBULAR DISORDER
This study aimed to assess the therapeutic effectiveness of biofeedback in the routine of a medical center for treating vestibular disorders, in reducing emotional, functional, and physical disability during three-month follow-up. Few are the studies currently available on the treatment of vertigo using biofeedback (Liu et al., This study showed that both groups had a high level of self-perceived disability at baseline. In particular, functional and emotional aspects were the most compromised, showing the impact of vertigo on the daily life of these patients. The DHI functional aspects considered the interference of dizziness on the performance of certain eye, head, and body movements, although focusing on the capacity of performing professional, domestic, social, and leisure activities as well as on the independency in performing tasks such as walking without help and walking around the house in the dark. The emotional aspects investigated the possible harm caused by dizziness on the quality of life, which can generate frustration, fear of going outside without company or staying at home alone, shame regarding clinical manifestations, worries about concentration disorders, a sensation of incapacity, changes in family or social relationships, and depression.After 3 months, there was a statistically significant difference between the two groups: the biofeedback group had lower DHI scores, indicative of less self-perceived disability than the control group. The reduced DHI score in the experimental group was indicative of a reduction in the self-perception of the incapacitating effects on the quality of life caused by dizziness. This may have been produced by the fact that those who attended biofeedback were learning to regulate respiratory frequency, heart rate, and muscle tension parameters, and this had a positive impact on the physical, functional, and emotional components related to vertigo. Moreover, between biofeedback sessions, patients were also asked to practice improving their breathing, relaxing muscles, and managing their disorder. It is possible that this treatment produced a reduction of dizziness and DHI scores and an improvement in physiological parameters in the biofeedback group.The differences between groups included both the DHI total score and all three sub-scales, although the greatest difference was the emotional component of the DHI. Furthermore, in the biofeedback group, the psycho-physiological parameters showed a reduction in the average values at three-month follow-up compared to the baseline. In particular, a reduction in the parameter relating to muscle tension, skin conductance, heart rate, and respiratory rate was observed, as well as lower maximal respiratory and heart rate. This study also demonstrated a reduction at three-month follow-up, not only in the average number of breaths but also in maximal respiratory and heart rates. During episodes of vertigo, patients showed an activation of the sympathetic nervous system with hyperventilation and an increase in their respiratory rate.The positive results achieved in only a few sessions can be explained by the fact that the first sessions were dedicated to hyperventilation, as they focused on respiratory regularization, which in turn reduces nystagmus. Indeed, the short-term therapeutic goal of each biofeedback session was the self-regulation of breathing and muscle tension through breathing and muscle relaxation procedures. It should be highlighted that patients with vertigo not only have respiratory deficits due to hyperventilation, but also have incorrect postures due to muscle rigidity caused by vertigo and motor instability. In addition, patients drastically reduce any movement of their head and neck due to the fear of the onset and worsening of the vertiginous symptom. After training with biofeedback, patients acquired the ability to regulate their respiratory rate by learning to recognize the trigger factors of respiratory activation. In muscle relaxation exercises, an improvement in vestibular function was also observed through guided exercises for the head, shoulders, and face, performed with eyes closed.Furthermore, for the reduction of muscle tension, the indications of Jacobson’s progressive relaxation protocol (Jacobson, Biofeedback allowed patients to view their movements and muscle tension in real time while performing relaxation exercises. Patients in the biofeedback group therefore acquired greater control of some of the physiological parameters. Indeed, biofeedback is based on the concept that if people are informed of the variations of a physiological parameter of which they are not normally aware, they can learn to control it to some extent. When people reduce muscular tension, then EMG activity also reduces, with a return sound signal that decreases in frequency. As such, patients are ‘guided’ to relax and learn to self-control their state of tension through subsequent tests (Biondi et al., 