Effects of contextual interference on feeding training in patients with stroke.

The contextual interference (CI) effect of motor skill has been demonstrated through numerous studies. However, few studies have reported on daily living tasks in patients with stroke. This study investigated the CI effect on spooning training in such patients. Fourteen right hemiparetic patients with stroke were assigned to one of two groups: a group with a random practice schedule or a group with a blocked practice schedule. The spooning task involved scooping go stones from a bowl 30 cm away in 3 different directions to a bowl in front of the patient. We evaluated the acquisition, retention, and transfer of motor learning for spooning. The transfer was evaluated while participants ate cereal in a bowl with a spoon. Upper extremity function, defined as far-transfer, was also evaluated using the box-and-block test. In the retention test, no significant difference between random and blocked practice groups was shown, although both groups showed differences between pre-test and post-test movement times. However, in the transfer test, the random practice group had a significantly shorter movement time than the blocked practice group and also revealed improvement between the pre- and follow-up tests. Additionally, in the far-transfer test, there were significant differences between the pre- and post-, and pre- and follow-up tests only in the random practice group. These findings show that the benefits of CI for transfer can be applied to the learning of feeding skills in patients with stroke and that although the blocked practice is also partially beneficial to long-lasting skill learning in a treatment setting, it may not be efficient under changed conditions. We also suggest the possibility that feeding training with the CI effect could apply to not only transfer but also to far-transfer.