Introduction

Aging is a biological process that affects all living things. The progressive decline in physiological capacities and the decline in the ability to perform daily environmental activities increase their vulnerability to diseases and problems. Balance is an integral part of all daily functions and motor skills that provide the necessary factors in the body to prevent falls [1]. One of the widespread and important problems in aging is a decrease in balance, an increase in falls, and a fear of falling [2]. Among the motor factors, researchers consider falls, a decrease in balance, and impaired gait patterns as key factors in reducing the motor efficiency of the elderly and believe that balance is the foundation of independent and active life [1]. Balance is a multifactorial ability that is affected by the strength, proprioception, and reaction speed of the individual and is the most important human ability to prevent falls. Balance can be static and dynamic; static balance includes the ability to maintain a level of support with minimal movement, while dynamic balance is the ability to perform a function or task while maintaining a stable body position [3].

Parkinson's disease is a type of neurological disease in which the affected person gradually loses their physical and mental abilities, and if an appropriate treatment strategy is not chosen, the severity of its symptoms increases more rapidly. The course of Parkinson's disease is progressive and leads to a gradual decrease in the person's performance. Therefore, in these patients, movements such as talking, writing, working, dressing, and even blinking may be performed slowly. Given the prevalence of this disease in the elderly and the decrease in the performance and quality of life of these people, various therapeutic interventions are needed for these people. Assessing the state of mind, performance, behavior and mood, daily life activities, and movement at each stage of the disease can help determine the best treatment. The use of medication can have side effects, so a way must be sought to improve their balance and motor function with minimal harm. New methods include exercise, balance training, and neurofeedback [4].

Neurofeedback training is one of the basic tools used among athletes and also in patients to achieve optimal performance [4]. Neurofeedback trains the brain to the appropriate activity or pattern during different sessions. This mode involves increasing or decreasing the activity of specific waves in specific areas of the brain. To achieve success using this method, people must put their bodies in an excited state and their minds in a relaxed state. This state is often called being in the “Zone”. Each of the brain waves (beta, alpha, theta, and delta) must be at a certain level of activity for this condition to occur [5]. Important indicators that are considered in neurofeedback training in terms of increasing performance and are tried to improve their performance and quality of life are concentration, attention and motivation, control of arousal level, desired level of automatic control, reduction of anxiety, rehabilitation in the treatment of brain injuries, rapid improvement of balance problems and being in the desired performance zone [6]. Investigating the effect of a course of neurofeedback training on some performance indicators among elderly people with Parkinson's is an issue that, according to the studies conducted so far, no documented research has been conducted on this subject in Iran, therefore the researcher seeks to investigate the effect of this type of exercise on balance and fear of falling in elderly people with Parkinson's.

Method: The present study is of an applied type in which it has been attempted to use a semi-experimental and descriptive-survey method. The statistical population in this study was all elderly men with Parkinson's in the age group of 60 to 70 years. From the statistical population, 30 people (15 people for each group) were selected conveniently and randomly assigned to two control and experimental groups. The experimental group underwent neurofeedback training. Static balance, dynamic balance, and fear of falling were measured from the participants in two stages before and after the neurofeedback training intervention. The Kolmogorov-Smirnov statistical test was used to determine the normality of the data distribution, and dependent and independent t-tests were used at a significance level of 0.05.

Results: To check the normality of the data, the Kolmogorov-Smirnov test was used. The results showed that the data had a normal distribution at a significance level of 0.05. Therefore, the relevant parametric tests can be used to analyze the data. The table below compares the static balance scores in the pre-test and post-test stages in the experimental and control groups.

According to the results of the independent t-test shown in the table above, it indicates that in the post-test stage, there is a significant difference between static and dynamic balance in the experimental and control groups, respectively (0.001), but there is no significant difference in the pre-test (0.119 and 0.138). Also, the dependent t-test results show a significant improvement in the experimental group from pre-test to post-test (0.001), but no significant improvement was observed in the control group (0.263 and 0.311). Therefore, it can be said that performing neurofeedback exercises has been able to significantly improve the static and dynamic balance of elderly people with Parkinson's. In addition to the balance variable, the table below compares the scores obtained by the subjects in the fear of falling test in the pre-test and post-test stages in the two experimental and control groups.

According to the results of the independent t-test shown in the table above, it can be seen that in the post-test there is a significant difference between the fear of falling scores in the experimental and control groups (0.001), but there is no significant difference in the pre-test (0.321). Also, the dependent t-test results show a significant improvement in the experimental group from the pre-test to the post-test (0.001), but no significant improvement was observed in the control group (0.262). Therefore, it can be said that performing neurofeedback exercises has been able to significantly improve the level of fear of falling in elderly men.

Conclusion: The results showed that in the post-test phase there was a significant difference between static and dynamic balance in the experimental and control groups. However, there was no significant difference in the pre-test. Also, the results of the dependent t-test in the experimental group showed a significant improvement in the experimental group from the pre-test to the post-test. These findings are consistent with the results of Shaw et al. on the effect of training courses on improving the balance of athletes and are consistent with the results of researchers such as Basta et al., Johnson et al., Parsai et al., Mohammadzadeh et al., Rezaei et al., Rahmani et al., and Mohammadzadeh et al. Since the subjects in the neurofeedback group scored better in both static and dynamic balance than the control group, it can be stated that neurofeedback training can be effective in improving the balance of the subjects [7, 8, 9, 10, 5, 11, 12].

According to the results of this study, it can be said that by using neurofeedback training, brain waves are activated and the person gradually learns to respond to specific symptoms at a specific time. Through self-regulation of the brain, the person learns to voluntarily influence the functioning of the automatic system affecting balance and increase his control over them, which improves balance. Sometimes it is necessary to continue the training process for a long time so that the brain can gradually regain its previous capabilities [10]. Hammond published his first experience in using neurofeedback to improve balance in 2005. Later, many people were treated quickly and effectively using this treatment protocol.

Regarding the fear of falling variable, the results showed that there was a significant difference between the experimental and control groups in the post-test phase. Therefore, considering the lack of significant difference between the two groups in the pre-test phase, it can be concluded that this difference was due to the effect of the independent variable (implementation of neurofeedback training). The results of this study were consistent with the results of the research of Golpaygani et al. (2009), Nik et al. (2016), Schmidt et al. (2010), and Saravankumar et al. (2014), [13, 14, 15]. In explaining the results, it can be said that considering that research has shown that neurofeedback training affect psychomotor functions and also increase the physical condition of individuals and increase the speed of processing fine motor coordination, visual-motor integration, visual perception, planning ability, and cognitive function, and ultimately, the fear of falling in elderly people is reduced, and if elderly people participate in neurofeedback programs, they will have more independence in performing daily activities.

Keywords: Neurofeedback training, static balance, dynamic balance, fear of falling, elderly, Parkinson's.

Ethical Considerations

Compliance with ethical guidelines

Ethical considerations have been taken into account in carrying out this research in accordance with the guidelines of the Ethics Committee of Islamic Azad University.

Funding

This study was extracted from the Ph.D. thesis of first author at Department of Sport Psychology of University.

Authors' contribution

All authors contributed equally to the conceptualization of the article and writing of the original and subsequent drafts.