Table 1.

Summary of reviewed articles.

References	Aim/Purpose	Design	Place of study	Sample size (attribution%)	Age group (year)	Intervention frequency & duration	Measurment instruments/Measures	Results	Conclusion
Tao et al., 2017	To investigate the impact of Tai chi chuan and Baduanjin on the cognitive control network (CCN) especially on the DLPFC part. To explain the underlying mechanism of the fact that Taichi and Baduanjin can help improve mental control function.	RCT	Gulou District, Fuzhou City, China	TC: 21 BDJ:16 CG:25 N = 62	50–70 years TC: 62.38 ± 4.55 BDJ: 62.33 ± 3.88 CG: 59.76 ± 4.83	TC: 60 min/d, 5d/week, last for 12 weeks. BDJ: 60 min/d, 5d/ week, last for 12 weeks. CG: maintain original physical activity habits for 12 weeks.	WMS-CR fMRI	In TC, the rsFC decreases significantly between the DLPFC and the left SFG and ACC. In BDJ, the rsFC decreases significantly between the DLPFC and the left putamen and insula. Mental control improvement was negatively associated with rsFC DLPFC-putamen changes across all subjects.	The practice of Tai Chi and Baduanjin could significantly increases the participant's mental control function.
Tao et al., 2016	To investigate how longitudinal Tai Chi Chuan and Baduanjin can modulate memory function and HPC resting-state functional connectivity (rs-FC) in elderly adults and the relation between them.	RCT	Gulou District, Fuzhou City, China	TC: 21 BDJ:16 CG:25 N = 62	50–70 years TC: 62.38 ± 4.55 BDJ: 62.33 ± 3.88 CG: 59.76 ± 4.83	TC: 60min/d, 5d/week, last for 12 weeks. BDJ: 60min/d, 5d/week, last for 12 weeks. CG: maintain original physical activity habits for 12 weeks.	MQ (WMS-CR) fMRI	The MQ significantly increased in TC and BDJ compared to CG. The rs-FC between the bilateral HPC and mPFC significantly increased in the TC compared to the CG. The rs-FC increases between the bilateral HPC and mPFC were significantly associated with corresponding memory function improvement across all subjects.	Both Tai Chi Chuan and Baduanjin may be effective exercises to prevent memory decline during aging.
Field et al., 2010	To determine the immediate effects of a combined form of Tai chi/yoga.	pretest/posttest	Coral Gables, Florida, United States.	N = 38 M = 2.7 on the HSI (57% Caucasian, 14% Hispanic, 14% Asian, 5% Black, and 10% other.)	21–59 years (averaged 41.0)	20 min long, including 10min of Taichi movements and 10 min of yoga postures.	STAI EKG EEG Math computations	A trend for increased EEG theta activity was detected but the result was not significant enough (p = 0.10).	The increased relaxation may have contributed to the increased speed and accuracy noted on math computations following the Tai chi/yoga class.
Wei et al., 2013	To investigate whether brain structural difference existed between highly experienced TCC practitioners and healthy control non-TCC practitioners.	Quasi-experiment	Beijing, China	ETC: 22(7 males) CG: 18 N = 40	ETC: 52 ± 6 years CG: 54 ± 6 years	No intervention.	ANT (RT & error scores) MRI	ETC showed significantly thicker cortex in the right PG, IS and MFS, also in the left MOTS and LS. Thicker cortex in left MOTS and LS was associated with greater intensity of TCC practice.	TCC practice could induce regional structural change in the brain. TCC might share similar patterns of neural correlates with meditation and aerobic exercise.
Wei et al., 2014	To examine TCC-associated changes in the human brain's intrinsic architecture and the relevant gains in behavioral performance.	Quasi-experiment	Beijing, China	ETC: 22(7 males) CG: 18(8 males) N = 40	ETC: 52.4 ± 6.8 years CG: 54.8 ± 6.8 years	No intervention.	ANT R-fMRI 2dReHo	The ETC had significantly greater fHo in the right PosCG and less fHo in the left ACC and the right DLPFC. Increased functional homogeneity in the PosCG was correlated with TCC experience. Decreases in fHo in the left ACC and increases in fHo in the right PosCG both predicted performance gains on ANT.	These findings provide evidence for the functional plasticity of the brain's intrinsic architecture toward optimizing locally functional organization.
Fong et al., 2014	To determine the relationship between physical activity and the task-switching aspect of executive function. (by investigating the modulating roles of age, modality of physical activity, and type of cognitive function using behavioral and event-related potential (ERP) assessments.	Quasi-experiment	Taipei, Taiwan	OEE: 16 OTC: 16 OSL: 16 YA: 16 N = 64	OA: 65–75 years OEE: 68.37 ± 3.68 OTC:67.31 ± 4.92 OSL: 68.93 ± 4.28 YA: 20–30 years (22.43 ± 2.58)	No intervention	Questionnaire MMSE IPAQ ERP	YA, OEE, and OTC had significantly larger P3 amplitude compared with OSL under homogeneous and heterogeneous conditions, while no differences were observed among the former three groups. YA exhibited shorter P3 latency than OSL. The ERP findings support the model of the STAC.	Regular participation in endurance exercise and Tai Chi Chuan may have equivalent beneficial effects on cognition at the behavioral and neuroelectric levels. Age and participation in physical activity influence the relationship between physical activity and task-switching, and a positive relationship was observed regardless of the modality of physical activity and type of cognitive function.
Li et al., 2014	To investigate the functional plasticity in resting-state connectivity of the prefrontal cortex and MTL in older adults.	RCT	Beijing, China	IG: 17(9 men) CG: 17(11 men) N = 34	IG: 68.6 ± 5.7 years CG: 71.7 ± 4.0 years	Cognitive intervention (MT& EFT): 1-h session, 3 sessions/week, last for 6 weeks Tai Chi: 1-h session, 3 sessions/week, last for 6 weeks, Yang-Style 24-form Tai Chi Group counseling: 90-min session, 1 time/week, last for 6 weeks CG: two 120 min health-related lectures	Participants criteria: MoCA CES-D ADL standardized assessments: PALT digit span TMT Stroop Test CFT Health status: MOS SF-36 SSRS SWLS IWB Image acquisition: fMRI	After the training activities, IG showed dramatic increment in functional correlation between mPFC and PHC.L, and significantly increased functional connectivity between the mPFC and left PHG. CG showed significantly decreased connectivity between mPFC and MFG. IG showed significant correlation between the changes in the FC of mPFC-PHG and the changes in cognitive performance (CFT). IG's level of mPFC-PHC.L connectivity at the post-training scan correlated significantly with individual performance on the TMT.	Multimodal intervention could postpone the effects of aging and improve the function of the regions that are most heavily influenced by aging, as well as play an important role in preserving the brain and cognition during old age.
Yin et al., 2014	To examine the effects of a multimodal intervention on spontaneous brain activity in healthy older adults, and the relationship between individual differences in baseline spontaneous activity and intervention-induced changes in behavioral performance.	RCT	Beijing, China	IG: 17(9 men) CG: 17(11 men) N = 34	61–79 years IG: 68.6 ± 5.7 years CG: 71.7 ± 4.0 years	Cognitive intervention (MT& EFT): 1-h session, 3 sessions/week, last for 6 weeks Tai Chi: 1-h session, 3 sessions/week, last for 6 weeks, Yang-Style 24-form Tai Chi Group counseling: 90-min session, 1 time/week, last for 6 weeks CG: two 120 min health-related lectures	Participants criteria: MoCA CES-D ADL standardized assessments: PALT digit span TMT Stroop Test CFT Health status: MOS SF-36 SSRS SWLS IWB Image acquisition: fMRI	IG showed significantly increased ALFF in the right MFG, left SFG and left ACL, while the mean ALFF in all three ROIs was significantly reduced in CG. In IG, increased ALFF in the right MFG was significantly correlated with changes in the TMT and SWLS, and in the left ACL the ALFF increase was significantly correlated with changes in social support. The baseline ALFF in the right MFG was significantly correlated with changes in the TMT and SWLS.	Multimodal intervention is effective in improving cognitive functions and well-being and can induce functional changes in the aging brain. The study suggested resting-state ALFF as a marker of intervention-induced plasticity in older adults.
Zheng et al., 2015	To explore the regionally functional plasticity by using the ReHo method to do an exploratory analysis in the whole brain.	RCT	Beijing, China	IG: 17(9 men) CG: 17(11 men) N = 34	IG: 68.59 ± 5.65 years CG: 71.65 ± 4.00 years	Cognitive intervention (MT& EFT): 1-h session, 3 sessions/week, last for 6 weeks Tai Chi: 1-h session, 3 sessions/week, last for 6 weeks, Yang-Style 24-form Tai Chi Group counseling: 90-min session, 1 time/week, last for 6 weeks CG: two 120 min health-related lectures	Participants criteria: MoCA CES-D ADL standardized assessments: PALT digit span TMT Stroop Test CFT Health status: MOS SF-36 SSRS SWLS IWB Image acquisition: fMRI	In IG, ReHo significantly increased in the left STG and left PCL, but decreased in the left MTG. In CG, ReHo significantly decreased in the left STG and PCL and increased in bilateral MTG. In IG, the intervention-related ReHo changes in the left STG were significantly positively correlated with changes in the CFT, and changes in the right MTG were negatively correlated with increase in the total PALT scores.	The present study confirms that the combined intervention induces regionally brain functional reorganization, and it could optimize the intrinsic functional brain architecture in the temporal cortex and cerebellum in the normal elderly.
Hawkes et al., 2014	To determine if people who were long-term Tai Chi practitioners would show enhancements to executive function and aerobic capacity.	Quasi-experiment	Eugene and Springfield, Oregon	TC: 10(3 female) MEG: 16(6 female) AEG: 16(8 female) SG: 12(10 female) N = 54	TC: 55.4 ± 12.99 MEG: 48.63 ± 15.00 AEG: 44.09 ± 16.2 SG: 46.92 ± 12.81	No intervention	Rockport 1-mile walk VSTS test with EEG Button press response	TC and MEG showed significantly larger P3b switch amplitudes than sedentary controls, while AEG and SG did not differ significantly on this key executive function measure. P3b switch latency showed no significant differences between groups.	Long-term practice of Tai Chi may benefit a neurophysiological index of executive function.
Liu et al., 2003	To examine the different physiological and psychological effects of 24TJQ in middle-aged women.	Quasi-experiment	Osaka, Japan	SkG: 10 NG: 10 N = 20	SkG: 50.56 ± 5.45 NG: 53.66 ± 4.9	6-min 24TJQ exercise, with 3-min rest (before) and recovery (after)	Concurrently measure with the exercise: HR RR exercise intensity physical fitness test EEG (used telemeter system to avoid noise) EMG ST	SkG showed significantly higher values of alpha%-power in eye-closed rest and recovery period compared to NG, but they have nearly the same values during exercise. SG showed a tendency of higher beta%-power during experiment than NG. SG showed a significant increase of alpha%-power in central region compared to occipital region after exercise while there was no significant change in NG.	24TJQ is beneficial to keep or improve agility, flexibility, and muscle strength or endurance ability in middle-aged women, and gives a special effect on the cardio-respiratory system.

RCT, randomized controlled trial; TC, Tai chi group; BDJ, Baduanjin group; CG: control group; WMS-CR, Wechsler Memory Scale–Chinese Revision; fMRI, functional magnetic resonance imaging; resting state functional connectivity, rsFC; DFPLC, bilateral dorsolateral prefrontal cortex; SFG, superior frontal gyrus; ACC, anterior cingulate cortex; MQ, memory quotient; HPC, hippocampus; mPFC, medial prefrontal cortex; HIS, Hollingshead Socioeconomic Index; STAI, the State Anxiety Inventory; HIS, Hollingshead Socioeconomic Index; STAI, State Anxiety Inventory; EKG, Electrocardiogram; EEG, Electroencephalogram; ETC, experienced Taichi practitioners; ANT, Attention Network Test; MRI, magnetic resonance imaging; PG, precentral gyrus; IS, insula sulcus; MFS, middle frontal sulcus; STG, superior temporal gyrus; MOTS, medial occipitotemporal sulcus; LS, lingual sulcus; R-fMRI, Resting-state functional magnetic resonance imaging; 2dReHo, 2d surface-based regional homogeneity; fHo, functional homogeneity; PosCG, post-central gyrus; ERP, event-related potential; OEE, older adults performing endurance exercise; OTC, older adults practicing Tai Chi Chuan; OSL, older adults with a sedentary lifestyle; YA, young adults; OA, older adults; MMSE, Mini-Mental State Examination; IPAQ, International Physical Activity Questionnaire; STAC, scaffolding theory of aging and cognition; MTL, medial temporal lobe; IG, Intervention group; MT, mnemonic training; EFT, executive function training; MoCA, Montreal Cognitive Assessment; CES-D, Center for Epidemiologic Depression Scale; ADL, activities of daily living; PALT, Paired Associative Learning Test; TMT, Trail Making Test; CFT, Category Fluency Test; MOS SF-36, Medical Outcomes Study Short Form-36; SSRS, Social Support Rating Scale; SWLS, Satisfaction with Life Scale; IWB, Index of Well-Being; mPFC, medial prefrontal cortex; HF, hippocampal formation; PHC, parahippocampal cortex; MFG, medial frontal gyrus; PHG, parahippocampal gyrus; FC, functional connectivity; SFG, superior frontal gyrus; ACL, anterior cerebellum lobe; ROI, region of interest; STG, superior temporal gyrus; PCL, posterior lobe of cerebellum; MTG, middle temporal gyrus; MEG, meditation plus exercise group; AEG, aerobic exercise group; SG, sedentary group; VSTS, Visuo-spatial task switch; 24TJQ, 24-style Taijiquan; SkG, skilled group; NG, novices' group; HR, heart rate; RR, respiratory rate; EMG, electromyography; ST, surface thermograph.