Learning without knowing: subliminal visual feedback facilitates ballistic motor learning

Research output: Contribution to conferenceConference abstract for conferenceResearch

During daily life we are constantly bombarded by sensory input providing information on the state of our body and the surrounding world. Although we do not consciously perceive all sensory inputs, these may nevertheless have consequences for our future behavior (e.g. Goodale and Milner). It is a well- described phenomenon that we may respond to features of our surroundings without being aware of them. It is also a well-known principle, that learning is reinforced by augmented feedback on motor performance. In the present experiment we hypothesized that motor learning may be facilitated by subconscious (subliminal) augmented visual feedback on motor performance. To test this, 45 subjects participated in the experiment, which involved learning of a ballistic task. The task was to execute simple ankle plantar flexion movements as quickly as possible within 200 ms and to continuously improve ballistic rate of force development (RFD) throughout a series of 40 trials. Following each trial subjects were provided visual augmented feedback on their performance in the form of dots presented on a monitor. The y-axis amplitude of the dots represented the obtained RFD. Participants were individually administered one of three durations of visual feedback: Supraliminal feedback with a dot display duration of 4s, subliminal feedback with an individually adjusted display duration of 13-26 ms or subliminal ‘empty’ feedback with a display duration of 0 ms. The individual perceptual threshold (duration of the feedback) was assessed in a separate test prior to the actual experiment and additional perceptual tests were performed after the learning session. In all 3 intervention groups motor performance improved as a result of practice. Not surprisingly the learning effect was significantly larger if subjects received supraliminal as compared to subliminal feedback. In the 0 ms feedback group motor performance increased only slightly indicating an important role of augmented feedback in learning the ballistic task. In the two groups who received subliminal feedback none of the subjects were able to tell what was on the screen during learning. Despite of this, there was a significantly larger learning effect in the subliminal 13-26 ms group compared to the subliminal 0 ms group. In conclusion, the results demonstrate that in addition to supraliminal feedback, subliminal feedback, which was not consciously perceived by the learner, indeed facilitated ballistic motor learning. This effect likely relates to multiple (conscious versus unconscious) processing of visual feedback and to the specific neural circuitries involved in optimization of ballistic motor performance.
Original languageEnglish
Publication date2010
Publication statusPublished - 2010
EventAnnual Meeting, Society for Neuroscience - San Diego, United States
Duration: 13 Nov 201017 Nov 2010

Conference

ConferenceAnnual Meeting, Society for Neuroscience
CountryUnited States
CitySan Diego
Period13/11/201017/11/2010

ID: 32432294