approximately 85% of patients who experience a stroke have a residual upper extremity ( ue ) 
 disability , and 5575% experience ue deficits that directly affect their quality of life 
 that directly affects their quality of life1 . stroke patients commonly use the unaffected ue for performing daily 
 living activities and avoid using the affected side ; this leads to decreased ue muscle 
 strength and movement and increased stiffness and can greatly affect independence in daily 
 life2 . recovery of ue function is 
 important for effective rehabilitation3 , 
 and the plasticity of neural networks is vital to recover damaged motor functions or acquire 
 new motor functions . the plasticity of networks in the brain is extremely important , as it 
 is the basis for recovery of cognitive function and motor learning4 . motor imagery ( mi ) is a conscious process that induces muscle activity related to an actual 
 motor output by creating a mental image of the action without the intent of performing 
 it5 . it is a cognitive method , which 
 instead of forcing a patient to learn new techniques , causes neural changes in order to 
 re - obtain motor techniques learned before the stroke damage or imitate the actions of 
 others6 . therefore , in this study , chronic stroke patients were monitored and examined to test the 
 effect of mi on rehabilitation of ue function and brain activation . motor imagery training 
 ( mit ) was designed to maximally activate the mirror neuron network during 18 specific daily 
 activities . the study hypothesis was that mit would provide sensory feedback and lead to 
 improvement of ue function in patients recovering from a stroke . the inclusion criteria 
 were as follows : ( 1 ) 612 months since stroke onset , ( 2 ) mini - mental state examination 
 ( mmse ) score > 24 points , and ( 3 ) able to sit independently for > 30 minutes . exclusion 
 criteria were as follows : ( 1 ) severe cognitive disability such as unilateral neglect , 
 dementia , depression , or seizure and ( 2 ) any musculoskeletal disorder including muscle 
 contracture or limitation of joint motion . prior to study initiation , the objectives and 
 requirements were explained to all participants , who signed a written informed consent form . this study was approved by the ethics committee ( kyunghee university medical center 
 institutional review board , komcirb-2013 - 050 ) . all participants underwent an evaluation of ue function at the start of the study . twenty - four participants were randomly assigned to either the mi or the control group . the 
 following clinical measures were used for assessing ue performance : fugl - meyer 
 assessment - upper extremity component ( fma - ue ) and wolf motor function test ( wmft ) . participants in both groups completed their training in 30-minute sessions , 3 times per 
 week , for 4 weeks . in addition , both groups received conventional physical therapy in 
 30-minute sessions , 5 times per week , for 4 weeks . the mi group was comprised 4 males and 8 
 females ; of these 4 were right hemiplegic and 8 were left hemiplegic . the mean patient age 
 was 64.2  years , mean height was 160.2  cm , and mean weight was 57.3  kg . the mean duration 
 after stroke onset was 8.1 months , and the average mmse score was 28.0 . the control group 
 was comprised 5 males and 7 females ; of these 6 were right hemiplegic and 6 were left 
 hemiplegic . the mean patient age was 59.4  years , mean height was 162.8  cm , and mean weight 
 was 62.9  kg . the mean duration after stroke onset was 8.5 months , and the average mmse score 
 was 28.3 . there were no significant differences between the groups at the onset of the 
 study . each participant in the mi group was asked to sit comfortably in a chair and imagine a task 
 by following an mi program that was played using computer monitor and speakers . the 
 participants performed 18 different tasks related to daily living ; the tasks involved 
 imagining the sequence of movements that should be performed using their hands . the tasks 
 included drinking water from a cup , setting a seal , turning pages of a book , plugging a cord 
 into an outlet , brushing their teeth with a toothbrush and toothpaste using both hands , 
 sorting chopsticks and spoons and putting them in a box , folding a towel , tearing off and 
 folding a piece of toilet paper , making a phone call , placing a card in their wallet , 
 changing batteries , opening and closing a zipper wallet , using scissors , spraying water with 
 a spray bottle , turning a faucet on and off , opening and closing a square airtight 
 container , opening a bottle top , and tightening shoelaces . to complete the mi exercise used 
 in this study , participants were asked to imagine the normal motion of their non - paralyzed 
 ue from an external perspective in order to mobilize visual imagery of their own motion to 
 call upon internal sensory information and kinematic imagery and various other sensory 
 details during the imagined motion of their non - paralyzed side . in order to confirm that the 
 subject was concentrating during the mi exercise , he or she was asked corresponding 
 questions every 5 minutes during the exercise . during each 30-minute session , mi was 
 conducted for 20 minutes following which the participants underwent physical training for 
 the final 10 minutes7 . the ue performance of each participant was evaluated using the fma - ue and wmft8 . it includes a ue subscale ( 33 items ; score range 066 ) and a lower extremity ( le ) 
 subscale ( 17 items ; score range 034 ) for a total score of 1009 , 10 . in the current study , 
 the shoulder , wrist , hand , and coordination sub - items were used . the wmft is a quantitative index of ue motor ability and is measured using timed and 
 functional tasks . the wmft has been posited as being useful for assessing the motor status 
 of higher - functioning chronic patients with stroke and traumatic brain injury in terms of 
 severity and ue motor deficiency . the inter - test and inter - rater reliability , internal 
 consistency , and stability of the test are excellent for both the performance time and 
 functional ability rating scale measures ( ranging from 0.88 to 0.98 , with most values close 
 to 0.95)11 . the spss 18.0 program ( spss , chicago , il , usa ) was used for all statistical analyses . the 
 shapiro - wilk test was used to determine the distribution of general participant 
 characteristics and outcome measures . paired t - tests and wilcoxon signed rank tests were 
 used for comparison of pre - test and post - test ue performance changes within each group , and 
 an independent t - test and mann - whitney u test were performed to compare the two groups . in the mi group , the average fma - ue score changed from 27.92 to 36.08 between pre- and 
 post - tests . thus , a significant increase of 8.17 points was observed ( p < 0.05 ) . in the 
 control group , the average fma - ue score changed from 28.58 to 31.00 between pre- and 
 post - tests . there was a significant difference in pre- and post - test fma - ue improvement 
 between the two groups ( p < 0.05 ) . in the mi group , the average wmft score changed from 
 44.75 to 51.00 between pre- and post - tests . a significant increase of 6.25 points was 
 observed ( p < 0.05 ) . in the control group , the average wmft score 
 changed from 35.08 to 40.17 between pre- and post - tests . there was no significant difference 
 in pre- and post - test wmft improvement between the two groups ( table 1table 1.changes in upper extremity performance ( n = 24)parametersvalueschange in valuesmi group ( n = 12)control group ( n = 12)mi group ( n = 12)control group ( n = 12)prepost prepost post - prepost - prefma - ue27.92 ( 7.65)36.08 ( 9.90)28.58 ( 5.05)31.00 ( 5.33)8.17 ( 2.55)2.42 ( 2.57)shoulder21.58 ( 3.37)25.83 ( 5.06)24.58 ( 3.78)25.33 ( 3.23)4.25 ( 3.05)0.75 ( 1.22)wrist1.42 ( 2.19)4.83 ( 1.64)1.58 ( 0.79)2.83 ( 1.12)3.42 ( 1.44)1.25 ( 1.42)hand2.67 ( 2.77)3.00 ( 3.16)1.08 ( 0.52)1.25 ( 0.62)0.33 ( 0.49)0.17 ( 0.39)coordination2.25 ( 0.45)2.42 ( 0.52)1.33 ( 1.23)1.58 ( 1.44)0.17 ( 0.39)0.25 ( 0.45)wmft44.75 ( 21.95)51.00 ( 21.56)35.08 ( 25.18)40.17 ( 25.30)6.25 ( 9.80)5.08 ( 3.68)values are presented as mean ( sd ) . wilcoxon signed rank test and 
 mann - whitney u test were used ; paired t - test and independent t - tests were 
 used ; mi : motor imagery ; fma : fugl - meyer assessment ; wmft : wolf motor function test ; 
 * p < 0.05 , compared with pretest values ; * * p < 0.01 , compared with pretest 
 values ; p < 0.01 , comparing post - pre between the two groups . ) . wilcoxon signed rank test and 
 mann - whitney u test were used ; paired t - test and independent t - tests were 
 used ; mi : motor imagery ; fma : fugl - meyer assessment ; wmft : wolf motor function test ; 
 * p < 0.05 , compared with pretest values ; * * p < 0.01 , compared with pretest 
 values ; p < 0.01 , comparing post - pre between the two groups . motor imagery is a mental exercise that uses an internal stimulus to induce motor 
 sensations from a psychological representation of action without the intent to perform that 
 action12 . it is known to induce 
 activation in brain areas and muscles similar to those involved in actual task performance . in addition , it mediates and accelerates learning of physical activities and changes in 
 motor function ; many studies have demonstrated the neurophysiological basis of mi exercises . stippich13 observed localized 
 stimulation of the precentral gyrus along the known somatotopic map when participants 
 imagined moving different body parts such as the foot , hand , or tongue . ehrsson14 observed the activation of corresponding 
 areas within the primary motor cortex along the somatotopic map when participants imagined 
 the movement of fingers , toes , and tongue . in the current study , a significant increase in 
 fma - ue score from 27.92 to 36.08 ( 8.17 points ) was observed after mit , during which the 
 patients were asked to imagine 18 different daily living activities . the shoulder , wrist , and hand scores of the fma - ue were notably increased after the 
 training . thus , activities of daily living such as folding a towel , using scissors , opening 
 and closing a square airtight container , using a wallet , plugging a cord into an outlet , and 
 sorting chopsticks and spoons and putting them in a box appear to improve strength in the 
 muscles surrounding the shoulder , wrist , and hand . wmft scores for the mi group also changed 
 significantly , from 44.75 to 51.00 ( an increase of 6.25 points ) . franceschini et al.15 showed that a focused and repetitive 
 task - oriented approach can restore ue function . the mit exercise used in this study involved repeatedly imagining a familiar motion and 
 then imitating the motion with a therapist , leading to an improvement in ue performance and 
 improvement in activities of daily living . celnik et al.16 showed that the daily task performance ability of 15 brain - injured 
 patients increased as a result of conducting imitation exercises after watching a clip of a 
 kitchen task such as opening and closing a refrigerator . the present study used an imagery 
 exercise instead of an action - observation training exercise , and the effectiveness was found 
 to be similar to results from the pilot study . the mit used in the current study involved 
 actions frequently used in daily living activities ; thus , when coupled with the use of 
 familiar objects to help trigger motivation through environmental cues relevant to the 
 patient s life , mit can help to advance ue rehabilitation . furthermore , mit can improve the 
 degree of ue motor performance in daily life as well as the patient s functional abilities . it has been shown that the motor system of the brain becomes more active with increased 
 similarity between an observed and performed motion17 , when performing goal - oriented rather than simple motions18 , 19 
 and when observing motion rather than a static image20 . the results of this study indicate that rehabilitation with mit combined with physical 
 training improves recovery in stroke patients . the fma - ue improvement was significantly 
 higher in the mi group compared to the control group . in particular , the fma - ue shoulder and 
 wrist sub - items improved in the motor imagery group . thus , mit has a positive influence on 
 ue performance by improving functional mobility in patients who have experienced a stroke . these results suggest that mit is feasible and beneficial for improving ue function in 
 stroke patients .
[ purpose ] the purpose of this study was to investigate whether motor imagery training has 
 a positive influence on upper extremity performance in stroke patients . [ subjects and 
 methods ] twenty - four patients 
 were randomly assigned to one of the following two groups : 
 motor imagery ( n = 12 ) or control ( n = 12 ) . over the 
 course of 4 weeks 
 , the motor imagery group participated in 30 minutes of motor imagery 
 training on each of the 18 tasks ( 9 hours total ) related to their daily living activities . 
 after the 4-week intervention period , the fugl - meyer assessment - upper extremity outcomes 
 and wolf motor function test outcomes were compared . 
 [ results ] the post - test score of the 
 motor imagery group on the fugl - meyer assessment - upper extremity outcomes was 
 significantly higher than that of the control group . in particular , the shoulder and wrist 
 sub - items demonstrated improvement in the motor imagery group . 
 [ conclusion ] motor imagery 
 training has a positive influence on upper extremity performance by improving functional 
 mobility during stroke rehabilitation . 
 these results suggest that motor imagery training 
 is feasible and beneficial for improving upper extremity function in stroke patients .