Table 1 Inclusion and exclusion criteria

• Aged 60 years or older

• Meets the diagnostic criterion of MCI [20]

 - report of a relative decline in cognitive functioning during

the past year by the participant or informant

 - normal general cognitive function, including the Mini-Mental

State Examination score of 25 ~ 30

Beijing version of the Montreal Cognitive Assessment score of ≤ 26

 - intact activities of daily living (Instrumental Activities of Daily Living scale of Lawton and Brody <18)

 - absence of dementia

• Have at least primary school education (≥ 5 years)

• Absence of self-reported visual or auditory impairment and color blindness

• Able to make an informed consent

• A history of neurological, psychiatric, and other severe medical issues that may affect brain function (i.e., epilepsy, Parkinson’s disease, head trauma, stroke, mental retardation, depression, anxiety, schizophrenia, alcohol dependency, or other addiction)

• Presence of unstable cardiac disease, significant cerebrovascular disease

• Taking any medications in the past 6 months may cause impaired or improved cognitive performance

• Participation in other research programs related to cognitive function during this trial.