Introduction: Bilateral upper limb task training (BT) is a promising intervention in stroke rehabilitation but its underlying mechanisms are unclear. The effects of BT on motor recovery and neurophysiological changes have not been reviewed together. This systematic review examines the relationships between changes in upper limb motor behavior and brain structure/function associated with BT after stroke, to elucidate the mechanisms underlying BT. Method: The complete holdings of 11 databases were searched up until 21 March 2012. Trial registers and reference lists of included studies and review papers were checked. Quantitative studies of any design employing BT with both arm motor and neurophysiological outcomes involving adult stroke survivors were included. Three authors independently screened abstracts, extracted data and appraised studies. Results: From 31,371 records, 8 studies were included. The wide range of study designs did not allow for meta-analysis. On methodological quality, one study was rated strong, three rated moderate and four rated weak. There is a large variation in the mode of BT used in the included studies. Three studies involved only in-phase BT; five studies involved both in-phase and anti-phase BT. Coupled movement and auditory cueing were incorporated in the BT tasks of four studies. Only three studies involved functional tasks. Functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) were used in four and six studies respectively. Conclusion: Few studies have examined the neural and behavioural effects following BT. BT comprises a wide range of training protocols. More research is needed to explain underlying mechanisms.
Choo, P. L., Gallagher, H. L., Morris, J., Pomeroy, V. M., & van Wijck, F. (2015). The neural correlates of bilateral upper limb training after stroke: a systematic review. Physiotherapy, 101, e248. https://doi.org/10.1016/j.physio.2015.03.428