developmental disabilities ( dd ) are a chronic delay in development , including conditions 
 such as cerebral palsy , intellectual development disorder , autism , and mixed type dd .
children with dd have problems with physical , cognitive , social , 
 sensory , and communication skills2 .
these 
 unique problems have a negative impact on the lives of their family as well as of the 
 children with dd1 . among the problems faced by children with dd ,
impairment in cognitive function and visual 
 perception causes problems in processing environmental stimuli , which makes it difficult for 
 them to adapt to their environment and live in independently2 . after entering elementary school , due to an increase in demanding 
 activities of daily living ,
problems caused by impairments of cognitive function and visual 
 perception become more evident3 . as 
 compared to prior to school entry ,
school - aged children are required to complete tasks 
 within a limited time at school or home and are expected to exhibit sophistication and 
 organization in their activities4 .
the literature indicates that there are intervention methods to improve cognitive function 
 and visual perception in children with dd , such as attention training programs , sensory 
 integration , and tabletop activities5 , 6 .
these methods are remedial approaches to 
 restore and facilitate the improvement of cognitive function and visual perception caused by 
 dd7 . although various conventional treatment methods for children with dd have been applied in 
 clinical settings , the controversies over the most effective protocol continues8 . in order to compensate for these problems , 

recently computer - based cognitive rehabilitation ( cbcr ) has been used in clinical 
 settings8 .
several studies concluded 
 that cbcr was an effective treatment for recovery of cognitive function and visual 
 perception9 .
however , most such studies 
 recruited adults or the elderly with stroke , traumatic brain injury , or dementia10 .
few studies have investigated the effects 
 of cbcr on cognitive function and visual perception in children with dd .
additionally , the 
 existing cbcr programs have predominantly targeted adults , and there is a lack of cbcr 
 programs for children8 . in 2011 , kim developed a cbcr program for children called cotras - c8 .
however , there is still insufficient evidence for the 
 clinical effectiveness of this program .
therefore , there is a need to investigate the 
 effectiveness of the cotras - c using objective methods .
accordingly , in this study , we conducted a randomized controlled trial to investigate the 
 effectiveness of the cbcr program for children with reference to their cognitive function 
 and visual perception .
we screened the 
 participants based on the inclusion criteria used in previous studies on cbcr for 
 children8 , 11 .
the inclusion criteria for participation were as follows : ( i ) dd 
 diagnosed by a pediatrician or rehabilitation physician ; ( ii ) children with dd , exhibiting 
 similar symptoms ( children with limited cognitive function and visual perception ) ; ( iii ) 
 presence of dd diagnosed by performance on the korean - developmental test of visual 
 perception-2 ( k - dtvp-2 ) ; ( iv ) a below normal score on the kaufman assessment battery for 
 children ( k - abc ) ; ( v ) ability to use the controller with the upper extremity without 
 spasticity ; and ( vi ) ability to understand instructions within three repeated explanations . 
 parents signed the informed consent form before commencement of the study , according to the 
 code of ethics of the world medical association ( declaration of helsinki , version 2004 ) .
the first was the k - dtvp-2 , 
 which comprises 8 sub - tests ( eye - hand coordination , position in space , copying , 
 figure - ground , spatial relations , visual closure , visual - motor speed , and form constancy ) . 

this test can be used to measure visual perception in children aged 4 to 8  years , and helps 
 to confirm the extent of visual perception disability according to developmental stages12 .
it provides an index of motor - reduced 
 visual perception ( mrp ) and visual motor integration ( vmi ) and combines the two indices to 
 interpret the overall level of visual perception ( general visual perception ; gvp)13 .
the second measure was the k - abc , 
 designed for use with children aged 2.5 to 12.5  years .
it assesses the intelligence quotient 
 and achievement , and entails 2 subscales , the achievement scale ( ach ) and mental processing 
 composite ( mpc ) , and 16 sub - tests .
the expected mean raw score is 100 , with a standard 
 deviation of 1514 .
the number of 
 sub - tests implemented changes depending on the age of the children tested .
therefore , in 
 this study , we used the sub - tests , depending on the age of the subjects .
all clinical 
 measurements were administered before and after the intervention by a blinded occupational 
 therapist with 4  years experience .
after the baseline session , eligible participants were 
 randomly allocated to either the control group ( cg ) or experimental group ( eg ) by a research 
 assistant who was not involved in the intervention . during the intervention sessions , the eg participants received 20 sessions ( 2 days a week 
 for 10 weeks ) of cbcr with the cotras - c program ( netblue co. , ltd , korea ) .
the cotras - c 
 consists of about 4,000 game - based training task on skills including attention , memory , 
 visuo - motor organization , coordination , and others .
the cotras - c with a character design and 
 voice suitable for children , makes the training easy by using the touch monitor and cotras - c 
 controller .
the difficulty level of all the tasks can be modified to suit the individual 
 participants abilities .
training data are automatically stored for accuracy analysis , which 
 helps develop an appropriate treatment plan8 , 11 . in this study
, the eg participants 
 received the visual perception training that comprised spatial relations , spatial memory , 
 concentration , eye - hand coordination , eye movement , and figure - ground perception .
the 
 duration of intervention for the cg participants was matched to that of the eg participants . 

the cg participants received a conventional cognitive rehabilitation that focused on visual 
 perception , using pencil and paper activities .
all participants received either the eg or cg 
 intervention for 30 minutes per a session .
the  test 
 and independent t - test were used to compare the differences in the general characteristics 
 of the two groups .
the independent t - test was used to compare the between group means and 
 changes in values , while the paired t - test was used to test the differences in the 
 continuous variables within the groups .
the 29 participants who fulfilled the inclusion criteria were randomly allocated to the two 
 groups as follows : 15 to the eg and 14 to the cg .
all participants characteristics have 
 been summarized in table 1table 1.subjects characteristicseg ( n = 15)cg ( n = 14)gendermale910female64age ( months)69.73  8.3371.93  8.07educationpreschool1010school54main care - givermother118grandmother46mean  standard deviation .
cg : control group ; eg : experimental group after intervention , the participants in both the groups showed a significant increase in 
 their scores on the k - dtvp-2 , ach of the k - abc , and mpc of the k - abc ( p < 0.001 ) ( tables 2table 2.subjects k - dtvp-2 scores before and after the interventionk - dtvp-2 ( gvp)pre - testpost - testeg ( n = 15)66.80 ( 3.63 ) 79.87 ( 2.92)cg ( n = 14)67.79 ( 2.78 ) 76.43 ( 3.90)*p < 0.05 , * * p < 0.001.mean ( standard deviation ) .
cg : control group ; eg : experimental group ; gvp : general 
 visual perception ; k - dtvp-2 : korean - developmental test of visual perception-2 and 3table 3.subjects k - abc scores before and after the interventionsachmpcpre - testpost - testpre - testpost - testeg ( n = 15)494.20 ( 25.46 ) 540.13 ( 23.91)68.60 ( 3.74 ) 75.56 ( 4.09)cg ( n = 14)508.64 ( 17.99 ) 531.42 ( 16.99)70.25 ( 3.18 ) 74.42 ( 3.26)*p < 0.05 , * * p < 0.001.mean ( standard deviation ) .
ach : achievement scale ; cg : control group ; eg : 
 experimental group ; mpc : mental processing composite ) .
additionally , there were significant differences in the changes in the 
 k - dtvp-2 , ach of the k - abc , and mpc of the k - abc between the two groups ( p < 0.001 ) ( table 4table 4.comparison of change in k - dtvp-2 and k - abc scoreseg ( n = 15)cg ( n = 14)k - dtvp-2 ( gvp)13.07 ( 1.44 ) 8.64 ( 3.15)k - abc ach45.93 ( 4.23 ) 22.79 ( 2.75 ) mpc6.90 ( 0.71 ) 4.18 ( 0.80)*p < 0.05 , * * p < 0.001.mean ( standard deviation ) .
ach : achievement scale ; cg : control group ; eg : 
 experimental group ; gvp : general visual perception ; k - abc : kaufman assessment battery 
 for children ; k - dtvp-2 : korean - developmental test of visual perception-2 ; mpc : mental 
 processing composite ) .
* p < 0.05 , * * p < 0.001 . mean ( standard deviation ) .
cg : control group ; eg : experimental group ; gvp : general 
 visual perception ; k - dtvp-2 : korean - developmental test of visual perception-2 * p < 0.05 , * * p < 0.001 .
ach : achievement scale ; cg : control group ; eg : 
 experimental group ; mpc : mental processing composite * p < 0.05 , * * p < 0.001 . mean ( standard deviation ) .
ach : achievement scale ; cg : control group ; eg : 
 experimental group ; gvp : general visual perception ; k - abc : kaufman assessment battery 
 for children ; k - dtvp-2 : korean - developmental test of visual perception-2 ; mpc : mental 
 processing composite
although studies on the effectiveness of the cbcr program for children are lacking8 , 11 , 
 it is increasingly used in clinical settings because of its advantages15 . therefore , the present study investigated the 
 effectiveness of the cbcr program with reference to cognitive function and visual perception 
 in children with dd .
the results of this study indicated that the cbcr program for children 
 may improve cognitive function and visual perception in children with dd .
the clinical 
 improvement in the k - dtvp-2 and k - abc scores was greater in the eg after intervention , as 
 compared to that in cg participants , confirming that cbcr is a more effective intervention 
 for children with dd as compared to conventional intervention .
most cbcr programs used in korea were developed for adults and these effectiveness has been 
 confirmed by several studies .
however , in some parts of cbcr program for adults , the stimuli 
 presented on the screen are not suitable for children and do not sustain interest in them . 

therefore , it is difficult to use such programs with children8 . to resolve these problems , kim developed a cbcr program for 
 children called cotras - c8 .
the effectiveness of cbcr with the cotras - c on cognitive function and visual perception 
 have been proved in several studies8 , 11 .
the use of a computer program helps in 
 the cognitive development of children by facilitating their intellectual ability , 
 stimulating curiosity , and allowing for creative thinking16 . in 2014 , park indicated that children with dd who received cbcr 
 with the cotras - c showed increased k - dtvp-2 and k - abc scores , which is consistent with the 
 results of the present study11 .
visual 
 perception is the ability to interpret and understand the environment by processing 
 information that is contained in visible light .
visual perception is closely related to 
 cognitive function , and therefore , an improvement in visual perception has been found to 
 have a positive impact on cognitive function13 , which was also confirmed in the results of the present study .
this study conclude that cbcr with the cotras - c can be used as a rehabilitation approach to 
 improve cognitive function and visual perception in children with dd , which suggests that 
 the cotras - c may be used as an alternative to other existing cbcr programs . although the sample size employed in the present study was small , the findings of this 
 study are significant because cbcr is a novel approach that broadens the scope of clinic 
 based intervention to home - based ones .
additionally , children living in a modern society 
 have several opportunities to receive this treatment17 .
the present study did not examine the effectiveness of cbcr with the cotras - c on the 
 activities of daily living of children with dd .
therefore , in future , studies with a large 
 sample size are needed to investigate the clinical effectiveness of the cotras - c as a 
 rehabilitation program for activities of daily living as well as cognitive function and 
 visual perception .
 [ purpose ] this study aimed to investigate the effects of a computer - based cognitive 
 rehabilitation program for children with developmental disabilities . 
 [ subjects ] subjects 
 included 29 children with developmental disabilities . [ methods ] the subjects were randomly 
 allocated to either the experimental group or control group . 
 experimental group subjects 
 received computer - based cognitive rehabilitation using the cotras - c while control group 
 subjects received conventional cognitive rehabilitation . 
 all subjects received 20 sessions 
 ( 2 days a week for 10 weeks ) of the experimental or control intervention for 30 minutes . 
 to compare the two groups , 
 the korean - developmental test of visual perception-2 and 
 kaufman assessment battery for children were performed before and after the intervention . 
 
 [ results ] both groups showed statistically significant improvement in their scores after 
 intervention . 
 additionally , there were significant differences in the scores between the 
 two groups . 
 [ conclusion ] the computer - based cognitive rehabilitation with cotras - c may be 
 helpful in improving the recovery of cognitive function and visual perception in children 
 with developmental disabilities . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION