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Effects of a Multicomponent Cognitive Stimulation Program on Cognitive Function Improvement Among Elderly Women

Open AccessPublished:November 07, 2019DOI:https://doi.org/10.1016/j.anr.2019.11.001

      Abstract

      Purpose

      This study was conducted to identify the effect of a multicomponent cognitive stimulation program (MCSP) on the improvement of older people's cognitive abilities. It also aimed to determine whether the effectiveness of the MCSP is related to age.

      Methods

      A one-group pretest-posttest design was used. The program was conducted once a week for 10 weeks. The Korean-Montreal Cognitive Assessment (K-MoCA) was used to measure cognitive functions before and after the MCSP. Participants included 37 people aged over 65 years with normal cognitive functions and living in I city. A paired t-test was used to compare K-MoCA scores before and after the MCSP, and a two-way analysis of variance was performed to confirm whether there is an interaction between the MCSP and age.

      Results

      It was found that the MCSP had a significant effect on improving cognitive functions (t = −5.15, p < .001). Regarding the subdomains, visuospatial/executive ability, recall, naming, and language ability showed significant effects; however, abstractive ability—which was not a focus of the program—showed no significant effect. There were differences in visuospatial/executive functions, language skills, and memory between the 65-79 years age group and the aged over 80 group. Further, regarding the relationship between the MCSP and age, it was found that their interaction was significant only with regard to visuospatial/executive ability.

      Conclusion

      The MCSP helps to improve the cognitive functions of the elderly; however, its effect differs between the young-old group and the old-old group. Therefore, age should be considered when developing MCSPs.

      Keywords

      Introduction

      In 2016, dementia prevalence among the elderly population (aged 65 years and above) reached 10.15%; it is estimated that the population will exceed 1 million people by 2024 because of the rapidly aging population in Korea. The major risk factor of dementia is age, and therefore, the risk of dementia among individuals aged 75-79 years is 5.8 times, and among those aged 80-84 years is 17.5 times higher than those aged 60-64 years [
      • Kim K.W.
      • Gwak K.P.
      • Kim B.S.
      • Kim B.J.
      • Kim G.R.
      • Kim T.H.
      • et al.
      Nationwide survey on the dementia epidemiology of Korea [Internet].
      ]. Cognitive function decline is a common phenomenon that occurs with age. Most elderly people experience age-related cognitive decline and thus become concerned about the possibility of senile dementia as age-related cognitive decline develops [
      • Mahncke H.W.
      • Connor B.B.
      • Appelman J.
      • Ahsanuddin O.N.
      • Hardy J.L.
      • Wood R.A.
      • et al.
      Memory enhancement in healthy older adults using a brain plasticity-based training program: a randomized, controlled study.
      ]. Even if cognitive decline insignificantly affects an elderly person's life, it can still negatively influence their quality of life, the frequency and quality of social interactions, etc. [
      • Mahncke H.W.
      • Connor B.B.
      • Appelman J.
      • Ahsanuddin O.N.
      • Hardy J.L.
      • Wood R.A.
      • et al.
      Memory enhancement in healthy older adults using a brain plasticity-based training program: a randomized, controlled study.
      ]. People with dementia suffer not only from cognitive decline but also from muscle weakness, postural instability, poor vision, and other neurological symptoms that tend to worsen over time, which can increase the risk of falls [
      • Muir S.W.
      • Gopaul K.
      • Odasso M.M.
      The role of cognitive impairment in fall risk among older adults: a systematic review and meta-analysis.
      ]. For these reasons, many persons with dementia lose their mobility and independence [
      • Giuli C.
      • Papa R.
      • Lattanzio F.
      • Postacchini D.
      The effects of cognitive training for elderly: results from My Mind Project.
      ]. Because dementia can completely alter one's quality of life, it is necessary to ensure the accuracy of diagnosis and secure effective treatment and more importantly, to take preventive measures before a diagnosis of dementia [
      • Giuli C.
      • Papa R.
      • Lattanzio F.
      • Postacchini D.
      The effects of cognitive training for elderly: results from My Mind Project.
      ]. However, it is a challenge to determine the appropriate timing for the application of preventive measures, because dementia does not occur all of a sudden; rather, it develops gradually, in the following stages: the symptomless stage, which occurs long before the person is diagnosed of dementia, where the changes and damage to the brain begin but result in no symptoms; moderate cognitive disorder, when the memory starts to decline, but it presents no significant problems in daily life; and finally, full-blown dementia, where daily life without another's help is impossible [
      • Alzheimer's Disease International (ADI)
      World Alzheimer Report 2018. The state of the art of dementia research: new frontiers [Internet].
      ]. Unlike other diseases, when a patient reaches the dementia stage without having access to effective preventive measures, it is difficult to expect recovery or to stop disease progression simply through medication or mental/social therapies [
      • Jacquemin A.
      Strategy and methods of cognitive rehabilitation in patients with Alzheimer's disease or other dementia.
      ]. In this stage, basic cognitive functions and mental health have already begun to deteriorate, regardless of the treatment method. Therefore, it is vital to detect dementia as early as possible and to control symptom deterioration as much as possible through active interventions, rather than follow-up measures that focus on treatment [
      • Lin J.S.
      • O'Connor E.
      • Rossom R.C.
      • Perdue L.A.
      • Burda B.U.
      • Thompson M.
      • et al.
      Screening for cognitive impairment in older adults: an evidence update for the U.S. Preventive Services Task Force. Evidence Synthesis Number 107.
      ].
      Many researchers have been devoting their efforts to the development of more effective medications for dementia, but they have so far yielded nonremarkable results. These failures have highlighted an increasing need for nonpharmacologic strategies based on cognitive stimulation, which has been shown to have significant effects in slowing and preventing dementia, without harmful side-effects [
      • Fisher B.C.
      The benefits of cognitive stimulation or training/rehabilitation upon brain function as an efficacious treatment for diagnosed dementia or mild cognitive decline.
      ]. Once degeneration of brain functions starts, changes are unlikely to be reversible, although it is still possible to preserve the plasticity of the cerebrum as well as the current status of the person with dementia. Therefore, an approach to maintaining and enhancing cognitive functions needs to be considered before reaching the dementia stage [
      • Smith G.E.
      • Housen P.
      • Yaffe K.
      • Ruff R.
      • Kennison R.F.
      • Mahncke H.W.
      • et al.
      A cognitive training program based on principles of brain plasticity: results from the Improvement in Memory with Plasticity-based Adaptive Cognitive Training (IMPACT) study.
      ].
      Cognitive-based interventions, which have no universal definition, include cognitive training, cognitive stimulation, cognitive rehabilitation, cognitive enrichment, and cognitive exercise [
      • Reijnders J.
      • van Heugten C.
      • van Boxtel M.
      Cognitive interventions in healthy older adults and people with mild cognitive impairment: a systematic review.
      ]. In general, the ultimate goal of cognitive training and cognitive rehabilitation is to prevent dementia and cognitive decline, reduce the rate of cognitive decline, recover patients' functions, or effectively respond to the disease progress [
      • Walton C.C.
      • Mowszowski L.
      • Lewis S.J.
      • Naismith S.L.
      Stuck in the mud: time for change in the implementation of cognitive training research in ageing?.
      ]. Cognitive stimulation, on the other hand, is based on the general view that a lack of cognitive activity hastens cognitive decline. Cognitive stimulation is often discussed in the context of normal aging as well as dementia. Cognitive stimulation can be an effective intervention for people with dementia, offering them a range of enjoyable activities that stimulate their thinking, attention, and memory, usually in a social setting (e.g., a small group) [
      • Woods B.
      • Aguirre E.
      • Spector A.E.
      • Orrell M.
      Cognitive stimulation to improve cognitive functioning in people with dementia.
      ,
      • Streater A.
      • Spector A.
      • Aguirre E.
      • Orrell M.
      Cognitive stimulation therapy (CST) for people with dementia in practice: an observational study.
      ]. Cognitive stimulation programs (CSPs) can help maintain or improve cognitive functions, particularly among healthy elderly people in the community, who are an at-risk group for cognitive decline [
      • Lin J.S.
      • O'Connor E.
      • Rossom R.C.
      • Perdue L.A.
      • Burda B.U.
      • Thompson M.
      • et al.
      Screening for cognitive impairment in older adults: an evidence update for the U.S. Preventive Services Task Force. Evidence Synthesis Number 107.
      ,
      • Sherman D.S.
      • Mauser J.
      • Nuno M.
      • Sherzai D.
      The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
      ,
      • Gates N.J.
      • Sachdev P.S.
      • Fiatarone Singh M.A.
      • Valenzuela M.
      Cognitive and memory training in adults at risk of dementia: a systematic review.
      ]. In particular, CSPs, which combine cognitive, emotional, and physical activities using various elements (e.g., music, art, and tactile sensation), can stimulate diverse aspects of cognitive function, making them more effective than single-component programs. Furthermore, they have the advantage of arousing participants’ interest more and encouraging more active participation [
      • Reijnders J.
      • van Heugten C.
      • van Boxtel M.
      Cognitive interventions in healthy older adults and people with mild cognitive impairment: a systematic review.
      ,
      • Tesky V.A.
      • Köbe T.
      • Witte A.V.
      • Flöel A.
      • Schuchardt J.P.
      • Hahn A.
      • et al.
      Feasibility and first results of a group program to increase the frequency of cognitively stimulating leisure activities in people with mild cognitive impairment (AKTIVA-MCI).
      ].
      However, previous studies on CSPs [
      • Lin J.S.
      • O'Connor E.
      • Rossom R.C.
      • Perdue L.A.
      • Burda B.U.
      • Thompson M.
      • et al.
      Screening for cognitive impairment in older adults: an evidence update for the U.S. Preventive Services Task Force. Evidence Synthesis Number 107.
      ,
      • Streater A.
      • Spector A.
      • Aguirre E.
      • Orrell M.
      Cognitive stimulation therapy (CST) for people with dementia in practice: an observational study.
      ,
      • Sherman D.S.
      • Mauser J.
      • Nuno M.
      • Sherzai D.
      The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
      ,
      • Young D.K.
      Multicomponent intervention combining a cognitive stimulation group and tai chi to reduce cognitive decline among community-dwelling older adults with probable dementia: a multi-center, randomized controlled trial.
      ] have included little information on each subdomain of cognitive function when reporting the program effects. For this reason, there are little understanding of the aspects that require further study for the application of CSPs. In addition, most previous studies in South Korea that measured the effects of CSPs for the elderly focused on dementia or moderate cognitive disorders. However, studies abroad have been gathering evidence for the effectiveness of such training on healthy elderly people with normal cognitive function [
      • Willis S.L.
      • Tennstedt S.L.
      • Marsiske M.
      • Ball K.
      • Elias J.
      • Koepke K.M.
      • et al.
      Long-term effects of cognitive training on everyday functional outcomes in older adults.
      ,
      • Kelly M.E.
      • Loughrey D.
      • Lawlor B.A.
      • Robertson I.H.
      • Walsh C.
      • Brennan S.
      The impact of cognitive training and mental stimulation on cognitive and everyday functioning of healthy older adults: a systematic review and meta-analysis.
      ]. Therefore, it will be useful to conduct practical research in Korea on whether CSPs can be effective to maintain and improve cognitive functions in older people over 65 years.
      In Korea, the age distribution of the elderly population increases as the elderly population increases, and the prevalence of dementia increases rapidly around 80 years [
      • Kim K.W.
      • Gwak K.P.
      • Kim B.S.
      • Kim B.J.
      • Kim G.R.
      • Kim T.H.
      • et al.
      Nationwide survey on the dementia epidemiology of Korea [Internet].
      ]. Ledgeur et al. [
      • Ledgeur N.
      • Heymans M.W.
      • Comijs H.C.
      • Huisman M.
      • Maier A.B.
      • Visser P.J.
      Age dependency of risk factors for cognitive decline.
      ] recommended changing the middle old age from 75 to 80 years in a recent study on age dependence of risk factors for cognitive decline. Therefore, it is necessary to verify that the CSP for the elderly has the same effect based on the middle old and old age inflection point of 80.
      This study seeks to verify whether a multicomponent CSP (MCSP) is effective in improving cognitive function among elderly people with normal levels of cognitive function. The results of this study can be used for planning community work projects needed to prevent the progression of mild cognitive impairment and dementia in elderly people with cognitive function decline as age increases.
      The specific study objectives are as follows: (1) to verify the effects of the MCSP on the improvement of cognitive functions among elderly people (in total and for specific subdomains), (2) to determine differences in the effects of the MCSP on cognitive function (in total and for specific subdomains) among the under-80 and 80-and-above age groups, and (3) to identify interactions between cognitive function enhancement through the MCSP and age.

      Methods

      Study design

      A one-group pretest-posttest design was used in this study.

      Setting and sample

      The participants were elderly people aged 65 years or older recruited from four senior citizen centers in Incheon city, Gyeyang county, South Korea. The four senior citizen centers selected for the study had similar environmental conditions, with about 40 registered elderly and 15 users and no experience of cognitive program. During the research, these senior citizen centers did not have any health-related programs other than the MCSP applied in this study.
      Inclusion criteria for the study participants were as follows: individuals who are over 65 years of age; have normal cognitive functions; can perform audits, including hearing, vision, and physical functioning; can participate in the program; do not plan to participate in other health programs during the program; and can complete the program. Exclusion criteria for the study participants were as follows: individuals with lower than normal cognitive functioning; below 65 years of age; poor vision, and hearing, and difficulty with the Korean-Montreal Cognitive Assessment (K-MoCA); and inability to participate in the program, including impairment in physical functioning. Of the elderly senior citizens visiting senior centers in Gyeyang county, 45 people who had normal cognitive functioning were selected to participate in this study. These 45 potential participants were explained the purpose of this study and the program plan. Among them, one person had no intention of participating in the program, three had difficulties in participating in the program regularly, and 41 wanted to participate in the program. The 41 people who indicated their intention to participate in the program were tested for visual acuity, hearing, and activities of daily living to confirm their independence. Among these 41 people, two had hearing problems and were thus excluded from the program. The program began with 39 participants, but one did not participate in the program for personal reasons from the third week, and one did not take the post-K-MoCA test, although this person completed the program. These two dropouts were men. The sample size was estimated using G-power program 3.1, based on a significance level of .05, an effect size of .5, and a power of .80, which resulted in a total of 35 participants as the minimum number; 39 persons were selected considering a dropout rate of 10%. Finally, 37 individuals completed the program, and their data were analyzed.

      Measurements

      This study used the K-MoCA [
      • Kang Y.W.
      • Park J.S.
      • YU K.H.
      • Lee B.C.
      A reliability, validity, and normative study of the Korean-Montreal cognitive assessment (K-MoCA) as an instrument for screening of vascular cognitive impairment (VCI).
      ] to examine the differences in cognitive functions before and after the MCSP. The K-MoCA was adapted by Kang et al. [
      • Kang Y.W.
      • Park J.S.
      • YU K.H.
      • Lee B.C.
      A reliability, validity, and normative study of the Korean-Montreal cognitive assessment (K-MoCA) as an instrument for screening of vascular cognitive impairment (VCI).
      ] from the MoCA [
      • Nasreddine Z.S.
      • Phillips N.A.
      • Bédirian V.
      • Charbonneau S.
      • Whitehead V.
      • Collin I.
      • et al.
      The montreal cognitive assessment, MoCA: a brief screening tool for mild cognitive impairment.
      ] to fit the Korean culture and linguistic characteristics. The K-MoCA is a stand-alone cognitive screening tool with superior sensitivity to cognitive functioning. It comprises a total of 30 points: 5 points for Visuospatial/Executive ability, 3 points for Naming, 6 points for Attention, 3 points for Language, 2 points for Abstraction, 5 points for Memory (Delayed Recall), and 6 points for Orientation. For the assessment of visuospatial/executive skills, respondents are required to draw a line, going from a number to a letter in ascending order (1 point); a cube (1 point); and a clock (3 points). For naming, respondents need to name the given animals. With regard to delayed memory, respondents first practice memorizing five words twice, and they are later asked to recall the words. For attention, the following is measured: forward and backward digit span (2 points), vigilance (respondents need to clap when the examiner says “Monday”) (1 point), and performance in a cognitive task (subtracting 7 from 100) (3 points). For language, the following is measured: sentence repetition (2 points) and verbal fluency (1 point). For abstraction, respondents are required to explain the similarity in each given pair of words. Finally, for orientation, respondents need to state the current year, month, date, day, and the place they are in at present.
      The K-MoCA test was conducted one-on-one by a researcher in a quiet, uninterrupted environment within the senior center office. The administration and scoring instructions for the MoCA were followed. The test took approximately 10-15 minutes.
      Participants' cognitive function was determined according to the standardized norm score table modified by Kang et al. [
      • Kang Y.W.
      • Park J.S.
      • YU K.H.
      • Lee B.C.
      A reliability, validity, and normative study of the Korean-Montreal cognitive assessment (K-MoCA) as an instrument for screening of vascular cognitive impairment (VCI).
      ] considering education and age. When the MoCA was first developed, the cut-off score was set as a single score (23 points), and a respondent with a score lower than 23 was determined to have cognitive degradation. However, considering that education and age influence cognitive ability, the standards were adjusted for age and education. Therefore, currently, different cut-off scores are applied as per education and age. The norm score table of K-MoCA developed by Kang et al. [
      • Kang Y.W.
      • Park J.S.
      • YU K.H.
      • Lee B.C.
      A reliability, validity, and normative study of the Korean-Montreal cognitive assessment (K-MoCA) as an instrument for screening of vascular cognitive impairment (VCI).
      ] was divided into 30 cells according to education level and age. Education level was categorized five groups (illiteracy, under 3 years, 4-6 years, 7-12 years, and over 13 years), and age was categorized six groups (50-64, 55-69, 60-74, 65-79, 70-84, and 75-90) that the midpoint ages were 57, 62, 67, 72, 77, and 82 years old. Overlapping age norm was used in the age category, and it was designed to find the midpoint age closest to the participant's age and apply the corresponding norm score. Normal cognitive function is determined according to the cell corresponding to the target age and education and following the cut-off points given in the corresponding column. The lowest cut-off point is 7 (75-90 years old and illiteracy groups), and the highest cut-off point is 27 (50-64 years of age and educated for over 13 years).
      The Cronbach α of the first MoCA developed by Nasreddine et al. [
      • Nasreddine Z.S.
      • Phillips N.A.
      • Bédirian V.
      • Charbonneau S.
      • Whitehead V.
      • Collin I.
      • et al.
      The montreal cognitive assessment, MoCA: a brief screening tool for mild cognitive impairment.
      ] was .83 and that of the K-MoCA [
      • Kang Y.W.
      • Park J.S.
      • YU K.H.
      • Lee B.C.
      A reliability, validity, and normative study of the Korean-Montreal cognitive assessment (K-MoCA) as an instrument for screening of vascular cognitive impairment (VCI).
      ] was .84; the Cronbach α of the instrument used in this study was .82.

      Data collection and analysis method

      MCSP intervention

      The MCSP was designed to improve general cognitive and social functions based on the clinical guidelines for occupational therapists [
      • Park S.H.
      Guide book for occupational therapist.
      ]. The program focuses on physical activities that enhance memory, attention, and visuospatial/executive ability. Additionally, the program includes some activities aiming to improve abstractive ability and orientation enhancement. The program was conducted in 8 sessions across 10 weeks from July to December 2018. The first session was conducted for 1 hour using rather simple tasks, and with each successive session, the difficulty of the tasks increased, such that participants had to perform multiple functions at a time or memorize more words. The program details are shown in Table 1.
      Table 1Multicompont Cognitive Stimulation Program.
      ScheduleProgramDomain
      Precognitive function testPretest and education about dementia
      • Improvement in the understanding about dementia
      1st WeekPaper puzzle
      • Attention function
      • Memory function
      • Perception function
      2nd WeekCard Flip game
      • Attention function
      • Memory function
      • Applying knowledge
      • Recreation and leisure
      3rd WeekPlay a musical instrument accord to number
      • Attention function
      • Memory function
      • Perception function
      • Basic learning
      4th WeekCreating a picture frame with a couple
      • Attention function
      • Memory function
      • Applying knowledge
      5th WeekDigit symbol/Insert +, - in blank
      • Attention function
      • Memory function
      • Mental functions of language
      • Calculation function
      6th WeekImitate a hand/calculate numbers by hand
      • Attention function
      • Memory function
      • Perception function
      • Basic learning
      7th WeekPerforming mission with two-person triangle
      • Attention function
      • Memory function
      • Applying knowledge
      • Undertaking multiple tasks
      8th WeekRecalling (specific year or season)
      • Attention function
      • Memory function
      • Global mental function
      Postcognitive function testPosttest and quiz about dementia• Improve for the understanding about dementia

      Data collection

      The list of all senior citizen centers in the city was reviewed, and senior citizen centers with similar environments (apartment environment) were selected first. Then, four senior citizen centers with the most similar conditions were selected after checking the nearby environment, the number of the registered elderly and users, prior implementation of the program, and other program implementation plans during this study.
      The K-MoCA was administered twice, and data were collected by the researchers a week before the program (pretest) and a week after the program (posttest). About 20 minutes were allotted to each individual. Before each test, the researcher instructed participants on how to complete the K-MoCA and how their data would be analyzed.

      Statistical analysis

      This study described the sample by calculating the frequencies and percentages of participants’ general characteristics (Table 2). To analyze differences in cognitive functions before and after the MCSP, we calculated means and standard deviations for the various cognitive functions and analyzed their differences using the paired t-test. Authors tested the normality of the data at pretest and posttest using both the Kolmogorov–Smirnov and Shapiro–Wilk tests for the entire sample and for each age group and found that the normality was secured (i.e., both tests were nonsignificant for an alpha of .05). To verify the differences between age groups, the Mann–Whitney U test was conducted. A two-way analysis of variance was also conducted to verify the interaction between the MCSP and age.
      Table 2General Characteristics of Participants (N = 37).
      Variablesn (%)
      Total37 (100.0)
      Age (yrs)65-7918 (48.6)
      80-and-above19 (51.4)
      Education period (yrs)0-314 (37.8)
      4-612 (32.4)
      7-1210 (27.1)
      Over 131 (2.7)
      CohabitantAlone18 (48.6)
      With partner8 (21.6)
      With another family without partner11 (29.8)
      Health insuranceNational health insurance32 (86.5)
      Medicare5 (13.5)
      Perceived economic statusAbove middle class22 (59.5)
      Lower15 (40.5)
      Number of social activity128 (75.7)
      28 (21.6)
      31 (2.7)
      Number of diseases04 (10.8)
      111 (29.8)
      218 (48.6)
      Above 34 (10.8)
      Note. yrs = years.

      Ethical consideration

      This study was approved by the common bioethics committee (Approval no. P01-201810-11-002). Before the research began, participants were informed about the study objectives and procedures to which they provided written consent.

      Results

      There were 39 participants in the program; two men, however, failed to finish the program. As a result, only 37 older women were included in this study. Among them, 18 were aged 65–79 years, and 19 were aged 80–91 years. Most participants had been educated for 0 to 3 years, followed by 4 to 6 years and 7 or more years. Participants’ average K-MoCA score before the intervention was 15.54 (±5.23).
      In the whole sample, the mean total score of the K-MoCA increased by 2.95 (±3.48) from 15.54 (±5.23) to 18.49 (±6.39), which was statistically significant (t = −5.15, p < .001). As for the subdomains, the authors found significant improvements in visuospatial/executive ability, naming, language ability, and delayed recall (memory). Although the mean scores for the subdomains of attention, abstractive ability, and orientation increased after the program, these increases were not significant (Table 3).
      Table 3Difference of Before and After the Program and Difference by Age groups (N = 37).
      CategoriesBefore programAfter programPre-Postt (p)
      M (±SD)M (±SD)M (±SD)
      Total K-MOCATotal15.54 (±5.23)18.49 (±6.39)−2.95 (±3.48)−5.15 (< .001)
      65-7917.71 (±4.34)21.06 (±5.24)−3.35 (±3.00)−4.61 (< .001)
      80-and-above13.70 (±5.31)16.30 (±6.58)−2.60 (±3.89)−2.99 (.007)
      U (p)97.00 (.026)95.50 (.022)
      Visuospatial-executiveTotal1.89 (±1.33)2.43 (±1.46)−0.54 (±1.24)−2.66 (.012)
      65-792.12 (±1.11)3.18 (±0.95)−1.06 (±1.09)−4.01 (.001)
      80-and-above1.70 (±1.49)1.80 (±1.54)−0.10 (±1.21)−0.37 (.716)
      U (p)126.00 (.187)77.50 (.004)
      NamingTotal1.97 (±1.04)2.27 (±0.99)−0.30 (±0.85)−2.14 (.039)
      65-792.35 (±1.00)2.71 (±0.47)−0.35 (±1.00)−1.46 (.163)
      80-and-above1.65 (±0.99)1.90 (±1.17)−0.25 (±0.72)−1.56 (.135)
      U (p)100.50 (.033)103.00 (.042)
      AttentionTotal3.65 (±1.70)3.76 (±1.53)−0.11 (±1.20)−0.55 (.586)
      65-794.29 (±1.90)4.18 (±1.59)0.12 (±0.86)0.57 (.579)
      80-and-above3.10 (±1.33)3.40 (±1.43)−0.30 (±1.42)−0.95 (.356)
      U (p)93.00 (.018)114.50 (.092)
      LanguageTotal1.30 (±0.85)1.76 (±0.86)−0.46 (±1.02)−2.75 (.009)
      65-791.65 (±0.70)1.82 (±0.88)−0.18 (±1.07)−0.68 (.508)
      80-and-above1.00 (±0.86)1.70 (±0.86)−0.70 (±0.92)−3.39 (.003)
      U (p)101.50 (.036)155.00 (.662)
      AbstractionTotal0.43 (±0.65)0.73 (±0.84)−0.30 (±0.91)−1.99 (.054)
      65-790.53 (±0.72)0.88 (±0.93)−0.35 (±1.00)−1.46 (.163)
      80-and-above0.35 (±0.59)0.60 (±0.75)−0.25 (±0.85)−1.31 (.204)
      U (p)148.50 (.517)143.00 (.424)
      Delayed recallTotal1.27 (±1.37)2.19 (±1.81)−0.92 (±1.55)−3.60 (.001)
      65-791.41 (±1.28)2.71 (±1.49)−1.29 (±1.61)−3.31 (.004)
      80-and-above1.15 (±1.46)1.75 (±1.97)−0.60 (±1.47)−1.83 (.083)
      U (p)143.50 (.424)115.50 (.970)
      OrientationTotal5.03 (±0.96)5.35 (±0.95)−0.32 (±0.97)−2.03 (.050)
      65-795.35 (±0.93)5.59 (±0.80)−0.24 (±0.97)−1.00 (.332)
      80-and-above4.75 (±0.91)5.15 (±1.04)−0.40 (±0.99)−1.80 (.088)
      U (p)106.50 (.052)123.00 (.158)
      Note. K-MoCA = K-Montreal Cognitive Assessment.
      This study next verified the difference in program effects by age (under 80 years and 80 years and above) (Table 3). The total score of the K-MoCA showed a significant increase in both age groups, just like for the whole sample. The authors similarly found that the subdomains showing nonsignificant changes in the whole sample also showed nonsignificant changes in both age groups, including attention, abstractive ability, or orientation. As for visuospatial/executive ability and delayed recall (memory), a significant difference was observed among those aged below 80 years (as in the whole sample) but no significant difference among those aged 80 years and above. In contrast, the increase in language ability was nonsignificant in the under-80 group but significant in the 80-and-above group.
      Next, this study compared the cognitive function scores between the age groups before and after the program. For the total score of the K-MoCA, and the scores of naming and attention, participants in the 80-and-above group had significantly lower scores than did those in the under-80 group both before and after the program. For visuospatial/executive ability, the authors observed no difference between age groups before the program; however, after the program, the score of the under-80 group was significantly higher than that of the 80-and-above group. In contrast, before MCSP, for language ability, the scores were 1.65 (±0.70) for the under-80 group and 1.00 (±0.86) for the 80-and-above group; the score of the under-80 group was significantly higher (p = .036). After the intervention, the score increased by 0.18 ± 1.07 points for the under-80 group, while the score of the 80-and-above group increased by 0.70 ± 0.92. Therefore, before the intervention, the language ability of the under-80 group was significantly higher than that of the 80-and-above group (p = .036), but after the intervention, there was no significant difference between the two groups (p = .662) (Table 3).
      Finally, a two-way analysis of variance was conducted to verify whether there was an interaction between program effect and age. It was found that the interaction between program effect and age was significant only for visuospatial/executive ability (Table 4).
      Table 4Interaction of the Program and Groups by Age (N = 37).
      Source of variance

      Dependent variable
      Program F (p)Age group F (p)Program*age group F (p)
      Visuospatial-Executive6.71 (.014)6.10 (.018)9.83 (.003)
      Naming4.55 (.040)7.66 (.009)0.40 (.531)
      Attention2.37 (.132)5.65 (.023)0.15 (.704)
      Language8.67 (.006)3.88 (.056)3.69 (.063)
      Abstraction1.74 (.196)1.53 (.040)0.47 (.498)
      Recall8.47 (.006)4.66 (.037)2.57 (.117)
      Orientation3.19 (.082)4.97 (.032)0.01 (.908)
      K-MoCA, Total19.64 (< .001)8.53 (.006)1.32 (.258)
      Note. K-MoCA = K-Montreal Cognitive Assessment.

      Discussion

      This study conducted an MCSP with local elderly people aged 65–91 years who had normal levels of cognitive function and found that the total K-MoCA significantly increased after the intervention. This result suggests that the intervention was effective in improving cognitive function. The MCSP is believed to improve cognitive functions because of its use of multisensory (visual, olfactory, hearing, and tactile) stimulation [
      • Baker R.
      • Dowling Z.
      • Wareing L.A.
      • Dawson J.
      • Assey J.
      Snoezelen: its long-term and short-term effects on older people with dementia.
      ], which our program similarly relied on, while also aiming to enhance memory and understanding of instructions. The findings of this study correspond with those of Young [
      • Young D.K.
      Multicomponent intervention combining a cognitive stimulation group and tai chi to reduce cognitive decline among community-dwelling older adults with probable dementia: a multi-center, randomized controlled trial.
      ], who applied a cognitive training program to local elderly people and found that it enhanced cognitive functions in general. A possible reason for the efficacy of the study is its focus on hand activities, such as posting paper puzzles, putting cards upside down, playing musical instruments, making photo frames, imitating hand shapes, and a three-legged race. Efficient use of hands can stimulate brain activities and cognitive functions, thereby delaying cognitive decline [
      • Kubota K.
      Hand and brain.
      ,
      • Stöeckel T.
      • Wunsch K.
      • Hughes C.M.
      Age related decline in anticipatory motor planning and its relation to cognitive and motor skill proficiency.
      ]. After Zhu et al. [
      • Zhu Y.
      • Wu H.
      • QI M.
      • Wang S.
      • Zhang Q.
      • Zhou L.
      • et al.
      Effects of a specially designed aerobic dance routine on mild cognitive impairment.
      ] made a general elderly population perform 35 minutes of dance three times a week to prevent cognitive decline, the total MoCA score increased by 1.5 points three months later and by 1.8 points after 6 months. However, in the present study, the MCSP improved the cognitive function more than the simple exercise program.
      In this study, certain subdomains—visuospatial/executive ability, naming, language, and delayed recall (memory)—showed significant differences before and after the intervention. Attention, abstractive ability, and orientation also improved, but not to a significant extent. Many previous studies verifying the effects of an MCSP have been conducted among elderly people with mild cognitive impairment or dementia, but not among those with normal cognitive function. Moreover, their investigation of subdomains was limited mostly to memory, etc. or they did not even consider the subdomains at all. These inconsistent details of past reports [
      • Lin J.S.
      • O'Connor E.
      • Rossom R.C.
      • Perdue L.A.
      • Burda B.U.
      • Thompson M.
      • et al.
      Screening for cognitive impairment in older adults: an evidence update for the U.S. Preventive Services Task Force. Evidence Synthesis Number 107.
      ,
      • Fisher B.C.
      The benefits of cognitive stimulation or training/rehabilitation upon brain function as an efficacious treatment for diagnosed dementia or mild cognitive decline.
      ,
      • Streater A.
      • Spector A.
      • Aguirre E.
      • Orrell M.
      Cognitive stimulation therapy (CST) for people with dementia in practice: an observational study.
      ,
      • Sherman D.S.
      • Mauser J.
      • Nuno M.
      • Sherzai D.
      The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
      ] make it difficult to compare our results with those of previous studies.
      In their systematic review of 27 randomized control trials and 8 clinical studies, Reijnders et al. [
      • Reijnders J.
      • van Heugten C.
      • van Boxtel M.
      Cognitive interventions in healthy older adults and people with mild cognitive impairment: a systematic review.
      ] reported that cognitive-based programs are helpful for improving memory performance, execution function, processing speed, attention, fluid intelligence, and subjective cognitive performance. As noted above, Young [
      • Young D.K.
      Multicomponent intervention combining a cognitive stimulation group and tai chi to reduce cognitive decline among community-dwelling older adults with probable dementia: a multi-center, randomized controlled trial.
      ] conducted cognitive stimulation training (which is not the same as our MCSP) among community-dwelling older adults, combining realistic orientation, physical games, food, sounds, senses, number games, word games, tai chi, etc., for 60 minutes twice a week over 14 sessions. Young found significant improvements in memory, content, and construction (using the Mattis Dementia Rating Scale), but did not find significant improvements in conceptualization or verbal initiation. In a meta-analysis of cognition-based interventions [
      • Sherman D.S.
      • Mauser J.
      • Nuno M.
      • Sherzai D.
      The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
      ], the content of the intervention appears to be the strongest predictor of the outcome, with the other components (e.g., duration) being non-significant. Accordingly, the scope of our MCSP intervention may be a reason for the inconsistent results in the subdomains. This is, however, difficult to clarify because the scope and focus of most other CSPs have not been specified [
      • Lin J.S.
      • O'Connor E.
      • Rossom R.C.
      • Perdue L.A.
      • Burda B.U.
      • Thompson M.
      • et al.
      Screening for cognitive impairment in older adults: an evidence update for the U.S. Preventive Services Task Force. Evidence Synthesis Number 107.
      ,
      • Sherman D.S.
      • Mauser J.
      • Nuno M.
      • Sherzai D.
      The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
      ,
      • Young D.K.
      Multicomponent intervention combining a cognitive stimulation group and tai chi to reduce cognitive decline among community-dwelling older adults with probable dementia: a multi-center, randomized controlled trial.
      ].
      In this study, the intervention had little effect on attention, abstractive ability, and orientation. Because abstractive ability was not a focus of this program, this was an expected result. Attention, on the other hand, was a focus of this program, and many of the program sessions dealt with attention, so the results are different from what was expected. In the case of orientation, the score before the MCSP was so high (83.8 out of 100 points) that no significant enhancement was expected. It is difficult to determine whether attention is a subdomain that is simply not influenced by the MCSP or if the program duration was insufficient. Possibly, attention did not improve because the attention element of the K-MoCA involves mathematical calculation (regular subtraction), which could have been difficult to improve for participants with a low level of education. Future studies should modify the program in this regard by applying another method to measure attention and calculation abilities. Tagliabue et al. [
      • Tagliabue C.F.
      • Guzzetti S.
      • Gualco G.
      • Boccolieri G.
      • Boccolieri A.
      • Smith S.
      • et al.
      A group study on the effects of a short multi-domain cognitive training in healthy elderly Italian people.
      ] examined the effect of 13 sessions of multidomain cognitive training (which is not the same as the intervention in our study) on healthy elderly people over an intervention of an hour per week. Their participants demonstrated improvement in overall cognitive skills, memory, and executive ability, but showed no significant improvement in attention. Tagliabue et al. [
      • Tagliabue C.F.
      • Guzzetti S.
      • Gualco G.
      • Boccolieri G.
      • Boccolieri A.
      • Smith S.
      • et al.
      A group study on the effects of a short multi-domain cognitive training in healthy elderly Italian people.
      ] explained that these results are likely determined by the nature, frequency, and strength of the program.
      In view of the results of previous studies, the reason that abstractive ability showed no significant enhancement in this study is probably that the program focused on task activities and stimulation to improve abstractive ability, which was insufficient. In addition, some of the subdomains showing nonsignificant enhancement could simply not be improved through such a short-term program.
      Visuospatial/executive ability improved probably because the MCSP included many related tasks, such as making artifacts and playing musical instruments. Delayed recall (memory) also showed significant improvement. The significant improvements in memory and mean visuospatial/executive ability in this study are similar to those in the findings of a previous report [
      • Kubota K.
      Hand and brain.
      ], wherein multidomain cognitive training improved executive ability and short-term memory in healthy elderly people. In contrast to our study, Martin and Stapleton [
      • Coe Á.
      • Martin M.
      • Stapleton T.
      Effects of an occupational therapy memory strategy education group intervention on Irish older adults' self-management of everyday memory difficulties.
      ] conducted memory training only, and thus, they reported improvements in memory only. While the program in the present study was not designed solely to improve memory, many of the activities in the program helped with memory enhancement, thus leading to a significant improvement in memory. Memory is the most basic element of cognitive function, and the MCSP has an advantage over other programs in that it enhances participants’ interest and participation, which is likely why it affects so many areas.
      Mahncke et al. [
      • Mahncke H.W.
      • Connor B.B.
      • Appelman J.
      • Ahsanuddin O.N.
      • Hardy J.L.
      • Wood R.A.
      • et al.
      Memory enhancement in healthy older adults using a brain plasticity-based training program: a randomized, controlled study.
      ] reported that after a memory training program, memory decline in the trained group was less than that in the untrained group. Tesky et al. [
      • Tesky V.A.
      • Köbe T.
      • Witte A.V.
      • Flöel A.
      • Schuchardt J.P.
      • Hahn A.
      • et al.
      Feasibility and first results of a group program to increase the frequency of cognitively stimulating leisure activities in people with mild cognitive impairment (AKTIVA-MCI).
      ] further reported that general cognitive ability changed insignificantly over 5 years among individuals who participated in speed and decision training, as compared with individuals who did not. These results indicate the importance of memory training. Although the participants’ cognitive functions were normal on pretest, their memory scores were low (Table 2). It is necessary, therefore, to emphasize memory training when designing MCSPs for elderly people who are not suffering from dementia. In addition, Suzuki et al. [
      • Suzuki H.
      • Kuraoka M.
      • Yasunaga M.
      • Nonaka K.
      • Sakurai R.
      • Takeuchi R.
      • et al.
      Cognitive intervention through a training program for picture book reading in community-dwelling older adults: a randomized controlled trial.
      ] reported that a picture reading program for elderly residents in the community did not improve their overall K-MoCA score but only significantly improved memory. Therefore, the MCSP, as conducted in this study, seems to be more effective in improving cognitive function than CSPs composed of a simple element.
      As discussed, the results of this study suggest that an MCSP that includes various factors, such as cognitive, emotional, and physical activities and music, art, and senses, seems to be more effective than one focused program, such as memory training, reading, and exercise. In addition, the MCSP that includes a variety of activities may be useful in stimulating the elderly's interest and helping them consistently participate in the program [
      • Tesky V.A.
      • Köbe T.
      • Witte A.V.
      • Flöel A.
      • Schuchardt J.P.
      • Hahn A.
      • et al.
      Feasibility and first results of a group program to increase the frequency of cognitively stimulating leisure activities in people with mild cognitive impairment (AKTIVA-MCI).
      ].
      The preceding sections have discussed the effects of the MCSP on the whole sample, without considering participants’ age. Next, the authors discuss differences in program effects between the under-80 and 80-and-above groups. It was found that the 80-and-above group did not show a significant enhancement in visuospatial/executive ability or delayed recall (memory). However, while the language ability of those in the 80-and-above group was low at pretest, their score showed a significant improvement at posttest. These findings indicate that elderly people in the 80-and-above group tend to be less involved in language activity, leading to degradation in their language ability that was later redeemed by the program. Because the findings differed by age, cognitive-based programs should be customized for each age group.
      The examination of the interaction effects (Table 4) revealed a significant interaction only for visuospatial/executive ability. This study found a significant increase in visuospatial/executive ability among those in the under-80 group, but no such increase among the 80-and-above group (Table 3). Thus, for those in the 80-and-above group, the MCSP was not effective for improving visuospatial/executive ability. This result reflects the fact that as people age, their senses degrade and physical activities decrease. Hence, different approaches should be adopted considering the age group.
      With respect to the duration, number of sessions, and session length of the cognitive-based interventions, according to a review and meta-analysis by Sherman et al. [
      • Sherman D.S.
      • Mauser J.
      • Nuno M.
      • Sherzai D.
      The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
      ], among 14 cognitive interventions studied, such a program is effective only if it lasts for at least 2 months. Another meta-analysis by Kelly et al. [
      • Kelly M.E.
      • Loughrey D.
      • Lawlor B.A.
      • Robertson I.H.
      • Walsh C.
      • Brennan S.
      The impact of cognitive training and mental stimulation on cognitive and everyday functioning of healthy older adults: a systematic review and meta-analysis.
      ] reported that for cognitive interventions to have beneficial effects on the elderly, at least 10 or more intervention sessions need to be conducted. In the present study, the minimum frequency to ensure that such an intervention has beneficial effects seemed to be eight sessions of 60 minutes each conducted over 2 months.
      Sherman et al. [
      • Sherman D.S.
      • Mauser J.
      • Nuno M.
      • Sherzai D.
      The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
      ] reported that the specific focus of the program's content appears to be a much stronger predictor of improved functioning than the duration, number of sessions, and length. Fisher [
      • Fisher B.C.
      The benefits of cognitive stimulation or training/rehabilitation upon brain function as an efficacious treatment for diagnosed dementia or mild cognitive decline.
      ] reported that the effectiveness and durability of interventions improved targeted cognitive abilities even despite training that was limited in time as well as number of training sessions. The results of these prior studies show that although the duration and number of sessions in the present study was not enough, the effects on the target capacities—visuospatial/executive ability and memory—were meaningful, while effects on (non-targeted) endurance and abstractive ability were less so.
      In this study, no additional follow-up program was conducted. However, Willis et al. [
      • Willis S.L.
      • Tennstedt S.L.
      • Marsiske M.
      • Ball K.
      • Elias J.
      • Koepke K.M.
      • et al.
      Long-term effects of cognitive training on everyday functional outcomes in older adults.
      ] conducted a cognitive training program targeting memory, inference, and execution speed among 500 normal elderly participants over 10 weeks and then followed it up with additional training sessions at 11 months and then 36 months. They found that those who participated in the additional training showed more sustained improvements in cognitive functions than did those who did not participate in additional training. Therefore, cognitive stimulation training for elderly people might need to continue at certain intervals instead of merely being a one-time program.

      Conclusion

      In conclusion, the MCSP for healthy elderly individuals with normal cognitive function seemed to be effective for improving overall cognitive function. This study also found that it is necessary to consider age when developing MCSPs, as the effects of the program will differ by age group (under-80 years and 80-and-above). As the intervention interacts with age for visuospatial/executive ability in particular, the authors cannot expect to see improvements in this ability over a short period of time among individuals in the 80-and-above group. In addition, this study confirmed that the effect of the MCSP may differ as per which factors are emphasized in the program. The results of this study can be used to develop health promotion programs to prevent the decline of cognitive function of the elderly in the community.
      Based on the findings, the authors offer the following suggestions when developing MCSPs for elderly people. First, it is necessary to strengthen the focus on abstractive ability and orientation, which did not improve in our study. Other physical activities should be added; for example, aerobic exercises have a positive effect on cognitive functions and brain plasticity [
      • Erickson K.I.
      • Colcombe S.J.
      • Wadhwa R.
      • Bherer L.
      • Peterson M.S.
      • Scalf P.E.
      • et al.
      Training-induced plasticity in older adults: effects of training on hemispheric asymmetry.
      ]. Second, as said earlier, age should be considered in developing MCSPs. Third, it is necessary to conduct follow-up training on a regular basis for elderly people who take part in MCSPs [
      • Willis S.L.
      • Tennstedt S.L.
      • Marsiske M.
      • Ball K.
      • Elias J.
      • Koepke K.M.
      • et al.
      Long-term effects of cognitive training on everyday functional outcomes in older adults.
      ]. Finally, to be able to identify and compare the effects of various cognitive-based intervention programs, it is necessary to avoid the use of unclear concepts and to attempt repeated research using a consistent intervention.
      This study was conducted with a one-group pretest-posttest design without a control group because of difficulties in participant recruitment. This limitation must be considered while interpreting the results of this study.

      Conflict of interest

      None.

      References

        • Kim K.W.
        • Gwak K.P.
        • Kim B.S.
        • Kim B.J.
        • Kim G.R.
        • Kim T.H.
        • et al.
        Nationwide survey on the dementia epidemiology of Korea [Internet].
        National institute of Dementia and Ministry of Health and Welfare, Sejong, Korea2017 ([cited 2019 Jan 30]. Available from:)
        • Mahncke H.W.
        • Connor B.B.
        • Appelman J.
        • Ahsanuddin O.N.
        • Hardy J.L.
        • Wood R.A.
        • et al.
        Memory enhancement in healthy older adults using a brain plasticity-based training program: a randomized, controlled study.
        Proc Natl Acad Sci USA. 2006; 103: 12523-12528https://doi.org/10.1073/pnas.0605194103
        • Muir S.W.
        • Gopaul K.
        • Odasso M.M.
        The role of cognitive impairment in fall risk among older adults: a systematic review and meta-analysis.
        Age Ageing. 2012; 41: 299-308https://doi.org/10.1093/ageing/afs012
        • Giuli C.
        • Papa R.
        • Lattanzio F.
        • Postacchini D.
        The effects of cognitive training for elderly: results from My Mind Project.
        Rejuvenation Res. 2016; 19: 485-494https://doi.org/10.1089/rej.2015.1791
        • Alzheimer's Disease International (ADI)
        World Alzheimer Report 2018. The state of the art of dementia research: new frontiers [Internet].
        ADI, London, UK2018 ([cited 2019 Jan 30] Available from:)
        • Jacquemin A.
        Strategy and methods of cognitive rehabilitation in patients with Alzheimer's disease or other dementia.
        Psychol Neuropsychiatr Vieil. 2009; 7 (French): 265-273https://doi.org/10.1684/pnv.2009.0182
        • Lin J.S.
        • O'Connor E.
        • Rossom R.C.
        • Perdue L.A.
        • Burda B.U.
        • Thompson M.
        • et al.
        Screening for cognitive impairment in older adults: an evidence update for the U.S. Preventive Services Task Force. Evidence Synthesis Number 107.
        U.S. Department of Health and Human Services, Rockland, MD2013 (AHRQ Publication No. 14-05198-EF-1)
        • Fisher B.C.
        The benefits of cognitive stimulation or training/rehabilitation upon brain function as an efficacious treatment for diagnosed dementia or mild cognitive decline.
        J Alzheimers Dis Park. 2014; 4: 161https://doi.org/10.4172/2161-0460.1000161
        • Smith G.E.
        • Housen P.
        • Yaffe K.
        • Ruff R.
        • Kennison R.F.
        • Mahncke H.W.
        • et al.
        A cognitive training program based on principles of brain plasticity: results from the Improvement in Memory with Plasticity-based Adaptive Cognitive Training (IMPACT) study.
        J Am Geriatr Soc. 2009; 57: 594-603https://doi.org/10.1111/j.1532-5415.2008.02167.x
        • Reijnders J.
        • van Heugten C.
        • van Boxtel M.
        Cognitive interventions in healthy older adults and people with mild cognitive impairment: a systematic review.
        Ageing Res Rev. 2013; 12: 263-275https://doi.org/10.1016/j.arr.2012.07.003
        • Walton C.C.
        • Mowszowski L.
        • Lewis S.J.
        • Naismith S.L.
        Stuck in the mud: time for change in the implementation of cognitive training research in ageing?.
        Front Aging Neurosci. 2014; 6: 43https://doi.org/10.3389/fnagi.2014.00043
        • Woods B.
        • Aguirre E.
        • Spector A.E.
        • Orrell M.
        Cognitive stimulation to improve cognitive functioning in people with dementia.
        Cochrane Database Syst Rev. 2012; 15: CD005562https://doi.org/10.1002/14651858.CD005562.pub2
        • Streater A.
        • Spector A.
        • Aguirre E.
        • Orrell M.
        Cognitive stimulation therapy (CST) for people with dementia in practice: an observational study.
        Br J Occup Ther. 2016; 79: 762-767https://doi.org/10.1177/0308022616668358
        • Sherman D.S.
        • Mauser J.
        • Nuno M.
        • Sherzai D.
        The efficacy of cognitive intervention in mild cognitive impairment (MCI): a meta-analysis of outcomes on neuropsychological measures.
        Neuropsychol Rev. 2017; 27: 440-484https://doi.org/10.1007/s11065-017-9363-3
        • Gates N.J.
        • Sachdev P.S.
        • Fiatarone Singh M.A.
        • Valenzuela M.
        Cognitive and memory training in adults at risk of dementia: a systematic review.
        BMC Geriatr. 2011; 11: 55https://doi.org/10.1186/1471-2318-11-55
        • Tesky V.A.
        • Köbe T.
        • Witte A.V.
        • Flöel A.
        • Schuchardt J.P.
        • Hahn A.
        • et al.
        Feasibility and first results of a group program to increase the frequency of cognitively stimulating leisure activities in people with mild cognitive impairment (AKTIVA-MCI).
        Clin Interv Aging. 2017; 12: 1459-1469https://doi.org/10.2147/CIA.S139146
        • Young D.K.
        Multicomponent intervention combining a cognitive stimulation group and tai chi to reduce cognitive decline among community-dwelling older adults with probable dementia: a multi-center, randomized controlled trial.
        Dementia (London). 2018 Nov 28; ([Epub ahead of print])https://doi.org/10.1177/1471301218814637
        • Willis S.L.
        • Tennstedt S.L.
        • Marsiske M.
        • Ball K.
        • Elias J.
        • Koepke K.M.
        • et al.
        Long-term effects of cognitive training on everyday functional outcomes in older adults.
        J Am Med Assoc. 2006; 296: 2805-2814https://doi.org/10.1001/jama.296.23.2805
        • Kelly M.E.
        • Loughrey D.
        • Lawlor B.A.
        • Robertson I.H.
        • Walsh C.
        • Brennan S.
        The impact of cognitive training and mental stimulation on cognitive and everyday functioning of healthy older adults: a systematic review and meta-analysis.
        Aging Res Rev. 2014; 15: 28-43https://doi.org/10.1016/j.arr.2014.02.004
        • Ledgeur N.
        • Heymans M.W.
        • Comijs H.C.
        • Huisman M.
        • Maier A.B.
        • Visser P.J.
        Age dependency of risk factors for cognitive decline.
        BMC Geriatr. 2018; 18: 187https://doi.org/10.1186/s12877-018-0876-2
        • Kang Y.W.
        • Park J.S.
        • YU K.H.
        • Lee B.C.
        A reliability, validity, and normative study of the Korean-Montreal cognitive assessment (K-MoCA) as an instrument for screening of vascular cognitive impairment (VCI).
        Korean J Clin Psychol. 2009; 28 (Korean): 549-562
        • Nasreddine Z.S.
        • Phillips N.A.
        • Bédirian V.
        • Charbonneau S.
        • Whitehead V.
        • Collin I.
        • et al.
        The montreal cognitive assessment, MoCA: a brief screening tool for mild cognitive impairment.
        J Am Geriatr Soc. 2005; 53: 695-699https://doi.org/10.1111/j.1532-5415.2005.53221.x
        • Park S.H.
        Guide book for occupational therapist.
        Soomoonsa, Seoul, Korea2018
        • Baker R.
        • Dowling Z.
        • Wareing L.A.
        • Dawson J.
        • Assey J.
        Snoezelen: its long-term and short-term effects on older people with dementia.
        Br J Occup Ther. 1997; 60: 213-218https://doi.org/10.1177/030802269706000507
        • Kubota K.
        Hand and brain.
        1st ed. Badabooks, Seoul, Korea2014 (Korean)
        • Stöeckel T.
        • Wunsch K.
        • Hughes C.M.
        Age related decline in anticipatory motor planning and its relation to cognitive and motor skill proficiency.
        Front Aging Neurosci. 2017; 9: 283https://doi.org/10.3389/fnagi.2017.00283
        • Zhu Y.
        • Wu H.
        • QI M.
        • Wang S.
        • Zhang Q.
        • Zhou L.
        • et al.
        Effects of a specially designed aerobic dance routine on mild cognitive impairment.
        Clin Interv Aging. 2018; 13: 1691-1700https://doi.org/10.2147/cia.s163067
        • Tagliabue C.F.
        • Guzzetti S.
        • Gualco G.
        • Boccolieri G.
        • Boccolieri A.
        • Smith S.
        • et al.
        A group study on the effects of a short multi-domain cognitive training in healthy elderly Italian people.
        BMC Geriatr. 2018; 18: 321https://doi.org/10.1186/s12877-018-1014-x
        • Coe Á.
        • Martin M.
        • Stapleton T.
        Effects of an occupational therapy memory strategy education group intervention on Irish older adults' self-management of everyday memory difficulties.
        Occup Ther Health Care. 2019; 33: 37-63https://doi.org/10.1080/07380577.2018.1543911
        • Suzuki H.
        • Kuraoka M.
        • Yasunaga M.
        • Nonaka K.
        • Sakurai R.
        • Takeuchi R.
        • et al.
        Cognitive intervention through a training program for picture book reading in community-dwelling older adults: a randomized controlled trial.
        BMC Geriatr. 2014; 14: 122https://doi.org/10.1186/1471-2318-14-122
        • Erickson K.I.
        • Colcombe S.J.
        • Wadhwa R.
        • Bherer L.
        • Peterson M.S.
        • Scalf P.E.
        • et al.
        Training-induced plasticity in older adults: effects of training on hemispheric asymmetry.
        Neurobiol Aging. 2007; 28: 272-283https://doi.org/10.1016/j.neurobiolaging.2005.12.012