Are People Adapted to Their Own Glasses?

Schot, Willemijn D.; Brenner, Eli; Sousa, Rita; Smeets, Jeroen B. J.

doi:10.1068/p7261

Cited by 10 publications

(7 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Note, however, that even after five days of training the learning was not complete, indicating that learning is slow. The slow learning is consistent with the finding that learning to switch to the mapping of one's own glasses may never be fully complete, even after more than a year of exposure to such switches (Schot et al 2012). …”

Section: Resultssupporting

confidence: 74%

Relative errors can cue absolute visuomotor mappings

Dam

Ernst

2015

Exp Brain Res

View full text Add to dashboard Cite

When repeatedly switching between two visuomotor mappings, e.g. in a reaching or pointing task, adaptation tends to speed up over time. That is, when the error in the feedback corresponds to a mapping switch, fast adaptation occurs. Yet, what is learned, the relative error or the absolute mappings? When switching between mappings, errors with a size corresponding to the relative difference between the mappings will occur more often than other large errors. Thus, we could learn to correct more for errors with this familiar size (Error Learning). On the other hand, it has been shown that the human visuomotor system can store several absolute visuomotor mappings (Mapping Learning) and can use associated contextual cues to retrieve them. Thus, when contextual information is present, no error feedback is needed to switch between mappings. Using a rapid pointing task, we investigated how these two types of learning may each contribute when repeatedly switching between mappings in the absence of task-irrelevant contextual cues. After training, we examined how participants changed their behaviour when a single error probe indicated either the often-experienced error (Error Learning) or one of the previously experienced absolute mappings (Mapping Learning). Results were consistent with Mapping Learning despite the relative nature of the error information in the feedback. This shows that errors in the feedback can have a double role in visuomotor behaviour: they drive the general adaptation process by making corrections possible on subsequent movements, as well as serve as contextual cues that can signal a learned absolute mapping.

show abstract

Section: Resultssupporting

confidence: 74%

Relative errors can cue absolute visuomotor mappings

Dam

Ernst

2015

Exp Brain Res

View full text Add to dashboard Cite

show abstract

“…Compared to the one-pair condition, the results for the two-pair condition showed a substantial amount of transfer between the hands, confirming the role of explicit learning of the contextual cues. The strong influence of explicit learning can account for many of the contextual cue effects reported in the literature and may account for the fact that we never fully implicitly compensate for our own glasses when putting them on [ 31 ].…”

Section: Discussionmentioning

confidence: 99%

Mapping Shape to Visuomotor Mapping: Learning and Generalisation of Sensorimotor Behaviour Based on Contextual Information

Dam

Ernst

2015

PLoS Comput Biol

View full text Add to dashboard Cite

Humans can learn and store multiple visuomotor mappings (dual-adaptation) when feedback for each is provided alternately. Moreover, learned context cues associated with each mapping can be used to switch between the stored mappings. However, little is known about the associative learning between cue and required visuomotor mapping, and how learning generalises to novel but similar conditions. To investigate these questions, participants performed a rapid target-pointing task while we manipulated the offset between visual feedback and movement end-points. The visual feedback was presented with horizontal offsets of different amounts, dependent on the targets shape. Participants thus needed to use different visuomotor mappings between target location and required motor response depending on the target shape in order to “hit” it. The target shapes were taken from a continuous set of shapes, morphed between spiky and circular shapes. After training we tested participants performance, without feedback, on different target shapes that had not been learned previously. We compared two hypotheses. First, we hypothesised that participants could (explicitly) extract the linear relationship between target shape and visuomotor mapping and generalise accordingly. Second, using previous findings of visuomotor learning, we developed a (implicit) Bayesian learning model that predicts generalisation that is more consistent with categorisation (i.e. use one mapping or the other). The experimental results show that, although learning the associations requires explicit awareness of the cues’ role, participants apply the mapping corresponding to the trained shape that is most similar to the current one, consistent with the Bayesian learning model. Furthermore, the Bayesian learning model predicts that learning should slow down with increased numbers of training pairs, which was confirmed by the present results. In short, we found a good correspondence between the Bayesian learning model and the empirical results indicating that this model poses a possible mechanism for simultaneously learning multiple visuomotor mappings.

show abstract

“…Yet the idea that adaptation is limited by forgetting has deep implications for how we interpret human performance. It implies that human performance is either inherently biased [23,24] or that unbiased performance must be achieved through other mechanisms [24]. Understanding the factors that limit adaptation also has applications in the development of rehabilitation programs that aim to reduce movement biases, for instance following injury.…”

Section: Introductionmentioning

confidence: 99%

Visuomotor Adaptation: How Forgetting Keeps Us Conservative

et al. 2015

Self Cite

View full text Add to dashboard Cite

Even when provided with feedback after every movement, adaptation levels off before biases are completely removed. Incomplete adaptation has recently been attributed to forgetting: the adaptation is already partially forgotten by the time the next movement is made. Here we test whether this idea is correct. If so, the final level of adaptation is determined by a balance between learning and forgetting. Because we learn from perceived errors, scaling these errors by a magnification factor has the same effect as subjects increasing the amount by which they learn from each error. In contrast, there is no reason to expect scaling the errors to affect forgetting. The magnification factor should therefore influence the balance between learning and forgetting, and thereby the final level of adaptation. We found that adaptation was indeed more complete for larger magnification factors. This supports the idea that incomplete adaptation is caused by part of what has been learnt quickly being forgotten.

show abstract

Are People Adapted to Their Own Glasses?

Cited by 10 publications

References 3 publications

Relative errors can cue absolute visuomotor mappings

Relative errors can cue absolute visuomotor mappings

Mapping Shape to Visuomotor Mapping: Learning and Generalisation of Sensorimotor Behaviour Based on Contextual Information

Visuomotor Adaptation: How Forgetting Keeps Us Conservative

Contact Info

Product

Resources

About