The Effect of Juggling as Dual-Task Activity on Human Neuroplasticity: A Systematic Review
Abstract
:1. Introduction
2. Methods
2.1. Search Strategies
2.2. Inclusion and Exclusion Criteria
2.3. Data Extraction
2.4. Quality Assessment of the Experiments
3. Results
3.1. Main Search
3.2. Study Characteristics
4. Discussion
4.1. Summary of the Main Results
4.2. Impact of Juggling on the Brain
5. Authors’ Conclusions
5.1. Limitations
5.2. Implications for Practice
5.3. Implications for Research
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Study | Country | Participants | Summary of the Intervention Procedure | Assessment | ||||||
---|---|---|---|---|---|---|---|---|---|---|
n | Groups | Description | Male | Female | Age (Mean ± SD) | Inclusion and Exclusion Criteria | ||||
Boyke et al. 2008 [20] | Germany | 93 | Intervention n = 25; control n = 25; * | Healthy adults | 39 | 54 | 60.0 | Healthy, without dementia, Parkinson’s disease, diabetes, hypertension. None of them could juggle. | Three-month period of juggling training and, after that, a three-month period without juggling. | MRI, VBM |
Berchicci et al. 2017 [21] | Italy | 28 | Expert jugglers (E) n = 14; non-jugglers (N) n = 14; | Healthy young adults | 23 | 5 | E: 32.0 ± 5.9 N: 30.0 ± 5.2 | E: able to juggle five or more balls with 10 years of experience. N: No prior experience in juggling. With normal or corrected-to-normal vision; without musculoskeletal injury; no reported history of psychiatric or neurological disease. | Two conditions: N: 1-ball fountain, 2-ball shower E: 2-ball shower, 3-ball shower 20 runs with 15 cycles of throws (150 trials for each task). | Kinematic data, EEG, sEMG |
Carius et al. 2016 [22] | Germany | 15 | No groups | Healthy expert jugglers | 15 | 0 | 26.3 ± 5.2 | Without neurological and psychological diseases. Assessment of expert skills: 5-ball cascade for at least 20 s in eight consecutive trials. | 6 trials in different conditions (2 balls in left hand, 2 balls in right hand, 3 balls bimanually, 5 balls bimanually, control for 1 Hz, control for 2 Hz) were performed 8 times for 20 s with a 60 s period of rest. | fNIRS, quantitative rating of juggling expertise |
Draganski et al. 2004 [23] | Germany | 24 | Jugglers n = 12; Non-jugglers n = 12; | Young adults | 3 | 21 | 22.0 ± 1.6 | No prior experience in juggling. | Three-month period of juggling and, after that, a three months period without juggling. | VBM |
Driemeyer et al. 2008 [24] | Germany | 20 | No groups | Healthy young adults | 9 | 11 | 26.5 | No prior experience in juggling, none suffered from any diseases. | 6 weeks of a juggling intervention and, after that, a 6-week period without juggling. | MRI |
Gerber et al. 2014 [25] | Germany | 32 | 5-ball-jugglers (5BJ) n = 16; controls (C) n = 16; | Healthy young adults | 28 | 4 | 5BJ: 26.9 C: 27.2 | Healthy without any psychiatric or neurological diseases. | None | MRI, VBM |
Sampaio-Baptista et al. 2014 [26] | United Kingdom | 44 | High intensity (HI) n = 22; low intensity (LI) n = 18; | Young adults | 22 | 22 | HI: 23.9 ± 3.6 LI: 23.8 ± 3.3 | Right-handed with no prior experience in juggling. | HI: 30 min of training per day for 29 days. LI: 15 min of training per day for 29 days. After that, 4 weeks without juggling. | Behavior, MRI, DTI |
Sampaio-Baptista et al. 2015 [27] | United Kingdom | 64 | High intensity (HI) n = 22; low intensity (LI) n = 18; Controls n = 20; | Young adults | 33 | 31 | 23.8 ± 3.5 | Right-handed with no prior experience in juggling | 5 days a week of juggling for 6 weeks. After that, a 4-week period without juggling. HI: 30 min of training per day. LI: 15 min of training per day. | Behavior, MRI |
Schiavone et al. 2015 [28] | Netherlands | 2 | Intermediate jugglers (I) and expert jugglers (E) | Intermediate and expert-level jugglers | 2 | 0 | 40 (I) and 22 (E) | I: able to juggle three balls comfortably for more than 60 s. E: able to juggle five or more balls. | First protocol for I and E: Five conditions (“rest”, “imagery”, “juggle”, “imagery hands”, “no balls”) Second protocol for E: Three conditions (3 balls, 5 balls, 7 balls) repeated three times. | EEG |
Scholz et al. 2009 [29] | Germany | 48 | Intervention n = 24; controls n = 24; | Healthy adults | 26 | 22 | 25.02 ± 3.34 | Healthy with no prior experience in juggling. | Six-week training period; four-week period without juggling | VBM, MRI |
Schultz et al. 2012 [30] | Germany | 30 | Intervention n = 15; controls n = 15; | Healthy adults | NI | NI | 24.3 ± 3.8 | Healthy with no prior experience in juggling. | Two months of juggling until participants were able to juggle a cascade for a minimum of 45 s | MRI |
Study | Study Design | Period and/or Frequency | Time Points of Measurement | Main Outcomes |
---|---|---|---|---|
Boyke et al. 2008 [20] | FUS | 3 months of training | Scan 1—baseline, Scan 2—3 months, Scan 3—6 months | Compared with the first time point (Scan 1), there was an increase in hMT/V5 on the right side during skill performance (Scan 2). This pattern reversed at the third time point (Scan 3). GM volume in the left frontal cortex, cingulate cortex, left hippocampus, and precentral cingulate cortex on the right increased during exercise. After the exercises were discontinued, the change subsided. Transient increases in the GM in hMT/V5, in the hippocampus on the right side, and bilaterally in the nucleus accumbens occurred only in the exercise group. In Scan 3, the effect was reversed. |
Berchicci et al. 2017 [21] | RCT | 1 session 2 conditions 10 s rest between conditions | During the intervention | The results showed large MRCP, starting before the action of juggling and lasting for the whole duration of the act. The tasks’ difficulty was related to large pN during preparation and execution of the juggling task in both groups. In the more experienced group, the results showed smaller prefrontal and larger frontal activity, mainly during juggling. Juggling practice may induce prefrontal neural plasticity, perhaps because juggling requires important level of coordination, focused attention, and balance during execution. |
Carius et al. 2016 [22] | CSS | 1 session 6 trials 8 × 20 s 60 s rest between trials | During the intervention | Execution of a complex task such as juggling is related to neurovascular changes in MT/V5 and also to changes in sensorimotor areas (M1, S1, PMC). The complexity of the task seems to modulate the abovementioned brain regions. The 5-ball cascade showed enhanced hemodynamic responses for oxy-Hb when compared with less complex tasks. |
Draganski et al. 2004 [23] | RCT | 3 months of training | Scan 1—baseline, Scan 2—3 months, Scan 3—6 months | Compared with the first time point (Scan 1), the second time point (Scan 2) showed a bilateral increase in GM volume in the hMT/V5 and in the left posterior medial sulcus. This change decreased at the third time point (Scan 3). These changes occurred only in the training group. |
Driemeyer et al. 2008 [24] | FUS | 6 weeks of training | Scan 1—Baseline, Scan 2—7 days, Scan 3—14 days, Scan 4—35 days, Scan 5—2 months after training, Scan 6—4 months after training | Compared with the first time point (Scan 1), subsequent time points at which skills were examined (Scans 2–4) showed a bilateral increase in hMT/V5 area, as well as a change in the GM in the frontal lobes, temporal lobes, and the cortex of the cingulate gyrus. This pattern reversed during subsequent time points (Scans 4 and 5). |
Gerber et al. 2014 [25] | V-BMS | - | Once/no intervention | Jugglers displayed regional GM density in the occipital and parietal lobes including the secondary visual cortex, the hMT+/V5 area bilaterally and the intraparietal sulcus bilaterally. In jugglers, the results showed a correlation between performance and GM density in the right hMT+/V5 area. |
Sampaio-Baptista et al. 2014 [26] | RCT | 29 days of training every day (low intensity: 15 min; high intensity: 30 min) | Scan 1—baseline, Scan 2—after training, Scan 3—4 weeks after training | Regions of the brain which had been identified as those where an increase in volume had been observed after juggling training [26] were correlated with the subsequent learning rate in a complex visuo-motor task. In these regions, a significant increase in GM volume after learning was observed in these groups of participants. The results showed that performance outcomes can have an important role in modulating positive structural changes in GM volume over certain time points. |
Sampaio-Baptista et al. 2015 [27] | RCT | 6 weeks of training, 5 sessions per week (low intensity: 15 min; high intensity: 30 min) | Scan 1—baseline, Scan 2—after training, Scan 3—4 weeks after training | In the low intensity group, the results showed increases in motor network connectivity and decreases in GABA. Scan 3 showed that the increased motor RSN strength was still present. This may suggest that changes in functional connectivity do not require ongoing practice to be maintained. In the high intensity training group, the results showed decreases in connectivity within the motor RSN, and no significant change in GABA. It was shown that lower intensity of practice might rely mostly on previously established functional connections. An increase in the strength of functional connectivity was observed. A higher intensity of practice might cause the formation of new connections and an increase in of circuit efficiency. The phenomenon of decreased functional connectivity was observed. |
Schiavone et al. 2015 [28] | CR | 1 session, 2 conditions | During the intervention | Higher power of oscillation across the scalp during juggling was observed in the case of expert jugglers. A higher alpha coherence during execution may be associated with hemispheric synchronization in the control and coordination of bimanual tasks. The dominance of the right hemisphere in this case possibly reflects a stronger visuomotor adaptation and a more efficient bimanual motor routine due to extensive practice. Intermediate jugglers were characterized by higher power in the theta and high gamma frequency bands and higher interhemispheric gamma coherence. |
Scholz et al. 2009 [29] | RCT | 6 weeks | Scan 1—baseline, Scan 2—6 weeks, Scan 3—10 weeks | A significant increase in FA was observed in the WM under the right posterior interparietal sulcus when comparing the first time point (Scan 1) with the second (Scan 2). This change occurred in the training group. After juggling, a significant increase in GM density was observed in the medial occipital and parietal lobe in cortical regions overlying the WM area. |
Schultz et al. 2012 [30] | RCT | 2 months Progress was reported daily by volunteers | Scan 1—baseline, Scan 2—at the end of intervention period, Scan 3—2 month after end | In juggle group of 225 voxels was obtained within the corpus callosum that showed increased FA between scan 1 and scan 2. This results were obtained just in juggle group. Also a mean of GM density increased in both hemispheres (medial occipital and parietal lobes) from scan 1 to scan 2. This effect was specific for experimental group. Decrease of WM and GM volume was not observed after period without intervention. |
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Malik, J.; Stemplewski, R.; Maciaszek, J. The Effect of Juggling as Dual-Task Activity on Human Neuroplasticity: A Systematic Review. Int. J. Environ. Res. Public Health 2022, 19, 7102. https://doi.org/10.3390/ijerph19127102
Malik J, Stemplewski R, Maciaszek J. The Effect of Juggling as Dual-Task Activity on Human Neuroplasticity: A Systematic Review. International Journal of Environmental Research and Public Health. 2022; 19(12):7102. https://doi.org/10.3390/ijerph19127102
Chicago/Turabian StyleMalik, Jakub, Rafał Stemplewski, and Janusz Maciaszek. 2022. "The Effect of Juggling as Dual-Task Activity on Human Neuroplasticity: A Systematic Review" International Journal of Environmental Research and Public Health 19, no. 12: 7102. https://doi.org/10.3390/ijerph19127102