parkinson s disease ( pd ) is caused by dopamine deficiency , which negatively affects 
 cerebral basal ganglia function1 . the 
 progressive chronic neurodegeneration of the brain associated with pd impairs balance and 
 motor ability . these chronic , negative effects on motor function are accompanied by memory 
 defects and a decreased ability to understand1 , 2 . in addition , emotional stability 
 deteriorates , which results in difficulty with activities of daily living ( adl ) and an 
 increasing feeling of despair and depression ; which causes a decline in the quality of life 
 of a patient2 , 3 . the treatment of pd with medication prescribed by doctors 
 replenishes the deficient dopamine level preventing or delaying nerve cell destruction , thus 
 delaying the progress of the disease4 . 
 however , in cases receiving long - term treatment , disease acceleration , motor disturbance , 
 cognitive impairment , or autonomic nerve malfunction may develop5 . exercise protects and promotes regeneration of damaged nerves , and enhances balance , 
 physical state , and independency , thereby facilitating adl . with an appropriate exercise 
 intensity , dopamine levels can be increased and motor disturbances can be improved6 , 7 . 
 therefore , treatment needs to integrate prescription medicines and exercise therapy . exercises in virtual reality provide visual , auditory , and tactile feedback , and the 
 exercise intensity can be modified by adjusting the difficulty of interactions and 
 intensity8 , 9 . there are no limitations in terms of time or place , thus enabling 
 continuous active exercise8 . virtual 
 reality dance exercise has been reported to have a positive effect on cerebral palsy , 
 dementia , and the recovery of physical function of stroke patients9,10,11,12 . however , there 
 are insufficient studies of the effects of virtual reality dance exercise on pd 
 patients . in this study , we aimed to examine the effect of virtual reality dance exercise on balance , 
 adl , and depressive disorder status of pd patients . twenty participants with pd were randomly assigned to either the experimental group ( 5 
 males , 5 females ) or the control group ( 5 males , 5 females ) . patients were able to 
 understand the study requirements and to communicate sufficiently , and could ambulate 
 independently . all participants were informed about the objectives and method of the study 
 and agreed to participate . the study protocol was approved by the institutional review board 
 of nambu university and was conducted in accordance with the ethical principles of the 
 declaration of helsinki . the general characteristics of the participants are listed in table 1table 1.general characteristics of each groupeg ( n=10)cg ( n=10)gender ( male / female)5/55/5age ( years)68.42.970.13.3height ( cm)165.19.1165.28.4weight ( kg)63.810.263.710.1meansd , eg : experimental group , cg : control group . the age ( meansd ) of the experimental group was 68.42.9  years , height was 
 165.19.1  cm , and weight was 63.810.2  kg . the age of the control group was 70.13.3  years , 
 height was 165.28.4  cm , and weight was 63.710.1  kg . meansd , eg : experimental group , cg : control group all participants received 30 minutes of neurodevelopment treatment ( ndt ) and 15 minutes of 
 functional electrical stimulation ( fes ) 5 times per week for 6 weeks . the virtual reality dance 
 exercise used the k - pop dance festival ( nintendo inc . , japan ) game for the wii ( nintendo 
 inc . , japan ) video game system . songs liked by patients were selected from the various 
 categories of k - pop music included in the software . a strap was used to fix the remote 
 control to the hands , and the patients tried to mimic the characters on the tv monitor . when 
 subjects properly mimicked the movement , they felt vibrations from the remote control and 
 heard the word the bbs consists of 14 items and 
 can be divided into balance for sitting , standing , and position changes . the score given 
 ranges from 0 to 4 points , with a highest possible score of 56 points , and higher scores 
 indicate better balance . the mbi 
 consists of 10 items : 5 points for personal hygiene , 5 points for taking a bath , 10 points 
 for eating , 10 points for using the toilet , 10 points for ascending stairs , 10 point for 
 putting on clothes , 10 points for defecation , 10 points for urination , 15 points for 
 walking , and 15 points for using the bed , with a highest possible score of 100 points . a 
 score of 024 points indicates complete dependence ; 2548 , maximum dependence ; 5074 , 
 partial dependence ; 7590 , slight dependence ; 9199 , minimum dependence ; and 100 , complete 
 independence . the presence and severity of depressive disorder was assessed using the beck 
 depression inventory ( bdi ) . the score ranges from 0 to 3 points , with a highest possible total 
 of 63 points . a score of 09 points indicates no depression ; 1015 , light depression ; 1623 , 
 heavy depression ; and 2463 , severe depression . the balance scores , adl score , and 
 depressive disorder status were recorded before and after the 6 weeks of treatment . the paired t - test was used to 
 compare pre- and post - treatment variables , and the independent t - test was used to compare 
 the treatment groups . the changes in balance are shown in table 
 2table 2.comparison of bbs , mbi , and bdi values between the experimental and control 
 groupsgroupprepostd - valuebbseg46.01.348.13.0 * 2.12.3*cg45.01.345.41.50.40.8mbieg87.91.491.13.0 * 3.23.0*cg87.41.788.21.80.81.6bdieg20.40.918.22.0*2.21.9*cg21.21.320.61.50.60.8meansd , * p<0.05 , eg : experimental group , cg : control group , d - value : 
 difference - value , bbs : berg balance scale , mbi : modified barthel index , bdi : beck 
 depression inventory . after 6 weeks of treatment , balance had significantly improved in the 
 experimental group ( 46.01.3 to 48.13.0 ; p<0.05 ) , while the control group showed no 
 significant improvement ( 45.01.3 to 45.41.5 ; p>0.05 ) . compared to the control group , 
 balance of the experimental group was significantly enhanced ( p<0.05 ) . after treatment , adl had 
 significantly improved in the experimental group ( 87.91.4 to 91.13.0 ; p<0.05 ) , while 
 adl of the control group showed no significant improvement ( 87.41.7 to 88.21.8 ; 
 p>0.05 ) . compared to the control group , adl of the experimental group were significantly 
 enhanced ( p<0.05 ) . after treatment , the depressive disorder 
 status significantly improved in the experimental group ( 20.40.9 to 18.22.0 ; p<0.05 ) , 
 while the depressive disorder status of the control group showed no significant improvement 
 ( 21.21.3 to 20.61.5 ; p>0.05 ) . compared to the control group , the depressive disorder 
 status of the experimental group was significantly improved ( p<0.05 ) . meansd , * p<0.05 , eg : experimental group , cg : control group , d - value : 
 difference - value , bbs : berg balance scale , mbi : modified barthel index , bdi : beck 
 depression inventory this study aimed to examine the effect of virtual reality dance exercise on the balance , 
 adl , and depressive disorder status of pd patients . the group comparison showed 
 balance of the experimental group significantly improved relative to the control group . the 
 present results corroborate those of esculier et al.13 , yen et al.14 
 and suarez et al.15 who showed that 
 virtual reality dance exercise enhanced the balance ability of pd patients . virtual reality 
 exercise provides visual and auditory feedback while watching the motion of the game 
 character , thus improving balance through integration of feedback from the scala vestibule 
 and proprioceptors . hence , this method can enhance the balance of pd patients8 , 9 , 13 . virtual reality exercise provides active learning and motivation to patients through an 
 experiential environment16 . yavuzer et 
 al.17 showed that virtual reality dance 
 exercise significantly enhances functional independence , and zhang et al.18 showed that it resulted in a significant 
 enhancement of adl . the present study also found there was a significant enhancement of adl 
 of pd patients following their performance of virtual reality dance exercise . dance exercise 
 helps to maintain and increase the range and approach of a patient s movement ; it also helps 
 with switching the direction of movement , when performing two simultaneous but separate 
 movements in conjunction with music . moreover , it provides various unpredictable movement 
 patterns , thus helping pd patients who have impaired adl19,20,21 . a depressive disorder may be caused by the disease itself or may be a side effect of the 
 treatment medication itself . depressive disorder delays the recovery of physical function 
 and makes it more difficult to perform adl . lee et al.22 and kim and lee23 demonstrated that virtual reality exercise reduces the presence and 
 severity of depressive disorders . the present study corroborates these previous findings 
 since it showed a beneficial effect of virtual reality exercise on the depressive disorder 
 status of pd patients . k - pop virtual reality dance exercise was performed by the subjects of 
 this study . k - pop dance utilizes repetitive lyrics and melodies and consists of simple brisk 
 rhythms and beats . because these features can be used as a targeted treatment and because 
 virtual reality exercise can elicit voluntary participation , the k - pop virtual reality dance 
 exercise may help improve the depressive disorder status of pd patients23 , 24 . a limitation of this study was that it was conducted with only 20 pd patients , thus making 
 it difficult to generalize the result to all patients with the disease . another limitation of this study is a lack of specific 
 history regarding the treatments the patients received prior to their participation . there 
 is a need for additional research on the effect of various exercise programs other than 
 virtual reality dance exercise .
[ purpose ] in this study , we examined the effects of virtual reality dance exercise 
 on the balance , activities of daily living and depressive disorder status of parkinson s 
 disease patients . 
 [ subjects ] twenty patients were assigned either the experimental group ( n 
 = 10 ) or the control group ( n = 10 ) . 
 all participants received 30 minutes of 
 neurodevelopment treatment and 15 minutes of functional electrical stimulation 5 times per 
 week for 6 weeks . 
 the experimental group additionally performed 30 minutes of dance 
 exercise . 
 balance , activities of daily living , and depressive disorder status were assessed 
 before and after the 6-week treatment period using the berg balance scale , the modified 
 barthel index , and the beck depression inventory . 
 the paired t - test was used to detect 
 differences before and after treatment , and the independent t - test was used to detect 
 differences between the treatment groups . [ results ] the values for balance , activities of 
 daily living , and depressive disorder status significantly differed between before and after 
 treatment in the experimental group , and significantly differed between the experimental 
 group and control group . 
 [ conclusion ] virtual reality dance exercise has a positive effect 
 on balance , activities of daily living , and depressive disorder status of parkinson s 
 disease patients .