TABLE 1.
Studies included in the meta‐analysis
| Study | Modality | PD, n | C, n | UPDRS‐III OFF | UPDRS‐III ON | Age of PD | Age of C | Foci, n | Contrast |
|---|---|---|---|---|---|---|---|---|---|
| Baglio et al, 2011 | fMRI | 15 | 11 | 21.5 | 66.5 | 66.9 | 6 | HC vs ON | |
| Task: | Button press with right index finger | ||||||||
| Buhmann et al, 2003 | fMRI | 8 | n/a | 54 | n/a | 2 | ON vs OFF | ||
| Task: | Random finger opposition task at 0.33 Hz with right and left hands | ||||||||
| Burciu et al, 2015 | fMRI | 20 | 20 | 31.9 | 65.8 | 64.8 | 20 | HC vs OFF | |
| Task: | Grip force task with or without feedback with more affected hand | ||||||||
| Caproni et al, 2013 | fMRI | 11 | 11 | 20 | 65 | 65.1 | 7 | HC vs OFF | |
| Task: | Tapping with right index finger | ||||||||
| fMRI | 11 | 11 | 20 | 65 | 65.1 | 15 | HC vs OFF | ||
| Task: | Sequence from dig I to V with right hand | ||||||||
| fMRI | 11 | 11 | 20 | 65 | 65.1 | 13 | HC vs OFF | ||
| Task: | Sequence with order dig I, III, V, II, IV with right hand | ||||||||
| Cerasa et al, 2006 | fMRI | 10 | 11 | 27.5 | 64.2 | 63.4 | 8 | HC vs OFF | |
| Task: | Synchronized tapping with right index finger at 1.33 Hz | ||||||||
| fMRI | 10 | 11 | 27.5 | 64.2 | 63.4 | 3 | HC vs OFF | ||
| Task: | Continuation of the tapping with right index finger without stimulus | ||||||||
| Drucker et al, 2019 | fMRI | 22 | 19 | 33.9 | 67.7 | 64.7 | 4 | HC vs OFF | |
| Task: | Externally cued foot‐tapping sequence | ||||||||
| fMRI | 22 | 19 | 33.9 | 67.7 | 64.7 | 6 | HC vs OFF | ||
| Task: | Internally cued foot‐tapping sequence | ||||||||
| Eckert et al, 2006 | fMRI | 9 | 9 | 20.6 | 10.7 | 63.3 | 60.6 | 18 | HC vs OFF |
| fMRI | 9 | 9 | 20.6 | 10.7 | 63.3 | 60.6 | 9 | HC vs ON | |
| fMRI | 9 | n/a | 20.6 | 10.7 | 63.3 | n/a | 4 | ON vs OFF | |
| Task: | Opening and closing of right fist at ~1 Hz | ||||||||
| Gonzalez‐Garcia et al, 2011 | fMRI | 17 | 10 | 41 | 64.4 | 8 | HC vs ON | ||
| Task: | Button presses with right and left hands in predefined order | ||||||||
| fMRI | 17 | 10 | 41 | 64.4 | 5 | HC vs ON | |||
| Task: | Button presses with right and left hands in random order | ||||||||
| Haslinger et al, 2001 | fMRI | 8 | 8 | 15.8 | 11.8 | 60.8 | 54.4 | 7 | HC vs OFF |
| fMRI | 8 | 8 | 15.8 | 11.8 | 60.8 | 54.4 | 8 | HC vs ON | |
| fMRI | 8 | n/a | 15.8 | 11.8 | 60.8 | n/a | 10 | ON vs OFF | |
| Task: | Joystick movements with right hand with 4 spatial degrees of freddom (dof) | ||||||||
| Holiga et al, 2012 | fMRI | 12 | n/a | 33.5 | 9.6 | 56 | n/a | 5 | ON vs OFF |
| Task: | Index‐to‐thumb opposition movements with right and left hands at 1 Hz | ||||||||
| Hughes et al, 2010 | fMRI | 16 | 15 | 31.3 | 18.9 | 63.9 | 66.5 | 10 | HC vs ON |
| Task: | Specified and chosen button presses with right hand | ||||||||
| Jia et al, 2018 | fMRI | 22 | 22 | 16.45 | 61 | 60.6 | 8 | HC vs OFF | |
| Task: | Self‐initiated tapping with right index finger at approximately 0.5 Hz | ||||||||
| Katschnig et al, 2011 | fMRI | 20 | 20 | 37.9 | 66.8 | 62.3 | 2 | HC vs OFF | |
| Task: | Dorsiflexion of right and left ankles at 1 Hz | ||||||||
| Kim et al, 2018 | fMRI | 16 | 15 | 36 | 63.1 | 64.1 | 6 | HC vs OFF | |
| fMRI | 16 | 15 | 36 | 63.1 | 64.1 | 19 | HC vs ON | ||
| fMRI | 16 | n/a | 36 | 63.1 | n/a | 5 | ON vs OFF | ||
| Task: | Two‐choice forced response task with fingers II and III of right hand | ||||||||
| Kraft et al, 2009 | fMRI | 12 | 12 | 21 | 13.9 | 60.8 | 53 | 12 | HC vs OFF |
| fMRI | 12 | 12 | 21 | 13.9 | 60.8 | 53 | 8 | HC vs ON | |
| fMRI | 12 | n/a | 21 | 13.9 | 60.8 | n/a | 4 | ON vs OFF | |
| Task: | Grip‐force task with right and left hands simultaneously | ||||||||
| fMRI | 12 | 12 | 21 | 13.9 | 60.8 | 53 | 13 | HC vs OFF | |
| fMRI | 12 | 12 | 21 | 13.9 | 60.8 | 53 | 4 | HC vs ON | |
| fMRI | 12 | n/a | 21 | 13.9 | 60.8 | n/a | 4 | ON vs OFF | |
| Task: | Grip‐force task with right and left hands alternating | ||||||||
| Maillet et al, 2012 | fMRI | 12 | n/a | 40.3 | 10 | 59.8 | n/a | 2 | ON vs OFF |
| Task: | Joystick movements with right hand with 4 spatial dof at 0.5 Hz | ||||||||
| Mak et al, 2016 | fMRI | 26 | 21 | 29 | 61.4 | 60.9 | 3 | HC vs ON | |
| Task: | Self‐initiated index finger tapping at ~0.2–0.3 Hz on most affected side | ||||||||
| fMRI | 26 | 21 | 29 | 61.4 | 60.9 | 3 | HC vs ON | ||
| Task: | Cued index finger tapping at ~0.2–0.3 Hz on most affected side | ||||||||
| Mallol et al, 2007 | fMRI | 13 | 11 | 22.6 | 64.9 | 61.9 | 13 | HC vs OFF | |
| Task: | Finger‐to‐thumb opposition and rotating movements of right hand | ||||||||
| Martin et al, 2019 | fMRI | 22 | 22 | 15.6 | 53 | 48.5 | 13 | HC vs OFF | |
| Task: | Self‐generated sequential button press with fingers I‐IV of most affected hand | ||||||||
| fMRI | 22 | 22 | 15.6 | 53 | 48.5 | 10 | HC vs OFF | ||
| Task: | Self‐generated sequential button press with fingers I‐IV of less affected hand | ||||||||
| fMRI | 22 | 22 | 15.6 | 53 | 48.5 | 13 | HC vs OFF | ||
| Task: | Visually‐cued sequential button press with fingers I‐IV of most affected hand | ||||||||
| fMRI | 22 | 22 | 15.6 | 53 | 48.5 | 5 | HC vs OFF | ||
| Task: | Visually‐cued sequential button press with fingers I‐IV of less affected hand | ||||||||
| Mattay et al. 2002 | fMRI | 7 | n/a | 8.8 | 5 | 55 | n/a | 7 | ON vs OFF |
| Task: | Button presses with right hand (0‐back task) | ||||||||
| Mohl et al, 2017 | fMRI | 26 | 21 | 33 | 24 | 62.2 | 61.6 | 1 | HC vs OFF |
| Task: | 1 Hz sequential tapping from fingers I‐V and vice versa with right hand | ||||||||
| Payoux et al, 2011 | PET | 8 | 10 | 22 | 12 | 62 | 67 | 3 | HC vs OFF |
| PET | 8 | n/a | 22 | 12 | 62 | n/a | 1 | ON vs OFF | |
| Task: | Joystick movements with right hand with 4 spatial dof at 0.33 Hz | ||||||||
| Pinto et al, 2011 | fMRI | 9 | 15 | 33 | 59 | 55 | 6 | HC vs OFF | |
| Task: | Joystick movements with right hand with 4 spatial dof at 0.5 Hz | ||||||||
| Planetta et al, 2015 | fMRI | 14 | 14 | 29.6 | 64 | 61.9 | 34 | HC vs OFF | |
| Task: | Cued and memorized pinch grip force task with most affected hand (collapsed) | ||||||||
| Poisson et al, 2013 | fMRI | 6 | 10 | 16 | 65 | 53.6 | 13 | HC vs OFF | |
| Task: | Finger‐thumb tapping with right hand at 1 Hz | ||||||||
| Rottschy et al, 2013 | fMRI | 23 | 23 | 23.9 | 67.2 | 65 | 8 | HC vs ON | |
| Task: | Direct repeat of sequence of 4 or 5 finger movements with both hands | ||||||||
| fMRI | 23 | 23 | 23.9 | 67.2 | 65 | 14 | HC vs ON | ||
| Task: | Delayed repeat of sequence of 4 or 5 finger movements with both hands | ||||||||
| Rowe et al. 2002 | fMRI | 12 | 12 | 33.7 | 62 | 62 | 2 | HC vs OFF | |
| Task: | Sequential finger movements of right hand at 0.33 Hz | ||||||||
| Sabatini et al, 2000 | fMRI | 6 | 6 | 16 | 61 | 59 | 15 | HC vs OFF | |
| Task: | Finger‐to‐thumb opposition movements and fist clenching with right hand | ||||||||
| Samuel et al, 1997 | PET | 6 | 6 | 17.7 | 70.2 | 64.3 | 7 | HC vs OFF | |
| Task: | Sequential finger movements of right hand at 0.33 Hz | ||||||||
| PET | 6 | 6 | 17.7 | 70.2 | 64.3 | 10 | HC vs OFF | ||
| Task: | Bimanual sequential finger movements at 0.33 Hz | ||||||||
| Tessa et al, 2010 | fMRI | 15 | 11 | 16.1 | 70.1 | 69 | 12 | HC vs OFF | |
| Task: | Continuous tapping of right hand | ||||||||
| Tessa et al, 2012 | fMRI | 15 | 13 | 16.3 | 68.1 | 64.2 | 4 | HC vs OFF | |
| Task: | Continuous writing of the figure “8” with right hand | ||||||||
| Tessa et al, 2013 | fMRI | 11 | 10 | 13.5 | 67.7 | 64 | 6 | HC vs OFF | |
| Task: | Continuous tapping of left hand | ||||||||
| Turner et al, 2003 | PET | 12 | 12 | 41.4 | 57 | 58 | 9 | HC vs OFF | |
| Task: | Tracking task with right hand | ||||||||
| Wu et al, 2005 | fMRI | 12 | 12 | 25.5 | 61.2 | 61.8 | 12 | HC vs OFF | |
| Task: | Sequential finger tapping with right hand at ~0.5 Hz | ||||||||
| Wu et al, 2010 | fMRI | 15 | 15 | 20.7 | 59.7 | 60.3 | 15 | HC vs OFF | |
| Task: | In‐phase movements of both index fingers at ~0.5 Hz | ||||||||
| fMRI | 15 | 15 | 20.7 | 59.7 | 60.3 | 20 | HC vs OFF | ||
| Task: | Antiphase movements of both index fingers at ~0.5 Hz | ||||||||
| Wu et al, 2015 | fMRI | 26 | 26 | 13 | 59 | 58.9 | 7 | HC vs OFF | |
| Task: | Tapping with right index finger at 0.3–0.5 Hz | ||||||||
| Wu et al, 2016 | fMRI | 18 | 18 | 20.4 | 60.4 | 59.9 | 11 | HC vs OFF | |
| fMRI | 18 | n/a | 20.4 | 60.4 | n/a | 7 | ON vs OFF | ||
| Task: | Free writing in PD patients with consistent micrographia | ||||||||
| fMRI | 18 | 18 | 19.1 | 59.6 | 60 | 9 | HC vs OFF | ||
| fMRI | 18 | n/a | 19.1 | 59.6 | n/a | 4 | ON vs OFF | ||
| Task: | Free writing in PD patients with progressive micrographia | ||||||||
| Wurster et al, 2015 | fMRI | 10 | 10 | 20.7 | 66.4 | 64.9 | 2 | HC vs ON | |
| Task: | Auditory‐cued button press with right index finger at 1, 2.5, and 4 Hz (collapsed) | ||||||||
| Yan et al, 2015 | fMRI | 11 | 12 | 20.1 | 61.5 | 65.5 | 5 | HC vs OFF | |
| Task: | Auditory‐cued finger‐to‐thumb movement with left hand | ||||||||
| fMRI | 11 | 12 | 20.1 | 61.5 | 65.5 | 4 | HC vs OFF | ||
| Task: | Auditory‐cued finger‐to‐thumb movement with right hand | ||||||||
HC, healthy control participants; OFF, Parkinson's disease patients off dopaminergic medication; ON, Parkinson's disease patients on dopaminergic medication; foci, number of activation foci reported in the respective study; n/a, not applicable.