Original research| Volume 98, ISSUE 10, P1924-1931, October 2017

Randomized Trial on the Effects of Attentional Focus on Motor Training of the Upper Extremity Using Robotics With Individuals After Chronic Stroke


      • Participants improved on motor outcomes after engaging in high-repetition robotics arm training.
      • There were no differences between external focus or internal focus of attention on retention of motor skills after 4 weeks of arm training.
      • Individuals with moderate-to-severe arm impairment may not experience the advantages of an external focus during motor training found in healthy individuals.
      • Attentional focus is most likely not an active ingredient for retention of trained motor skills for individuals with moderate-to-severe arm impairment.



      To compare the long-term effects of external focus (EF) and internal focus (IF) of attention after 4 weeks of arm training.


      Randomized, repeated-measures, mixed analysis of variance.


      Outpatient clinic.


      Individuals with stroke and moderate-to-severe arm impairment living in the community (N=33; withdrawals: n=3).


      Four-week arm training protocol on a robotic device (12 sessions).

      Main Outcome Measures

      Joint independence, Fugl-Meyer Assessment, and Wolf Motor Function Test measured at baseline, discharge, and 4-week follow-up.


      There were no between-group effects for attentional focus. Participants in both groups improved significantly on all outcome measures from baseline to discharge and maintained those changes at 4-week follow-up regardless of group assignment (joint independence EF condition: F1.6,45.4=17.74; P<.0005; partial η2=.39; joint independence IF condition: F2,56=18.66; P<.0005; partial η2=.40; Fugl-Meyer Assessment: F2,56=27.83; P<.0005; partial η2=.50; Wolf Motor Function Test: F2,56=14.05; P<.0005; partial η2=.35).


      There were no differences in retention of motor skills between EF and IF participants 4 weeks after arm training, suggesting that individuals with moderate-to-severe arm impairment may not experience the advantages of an EF found in healthy individuals. Attentional focus is most likely not an active ingredient for retention of trained motor skills for individuals with moderate-to-severe arm impairment, whereas dosage and intensity of practice appear to be pivotal. Future studies should investigate the long-term effects of attentional focus for individuals with mild arm impairment.


      List of abbreviations:

      EF (external focus), FMA (Fugl-Meyer Assessment), IF (internal focus), WMFT (Wolf Motor Function Test)
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