Bottom-up and top-down influences at untrained conditions determine perceptual learning specificity and transfer
- Peking University, China
Abstract
Perceptual learning is often orientation and location specific, which may indicate neuronal plasticity in early visual areas. However, learning specificity diminishes with additional exposure of the transfer orientation or location via irrelevant tasks, suggesting that the specificity is related to untrained conditions, likely because neurons representing untrained conditions are neither bottom-up stimulated nor top-down attended during training. To demonstrate these top-down and bottom-up contributions, we applied a 'continuous flash suppression' technique to suppress the exposure stimulus into sub-consciousness, and with additional manipulations to achieve pure bottom-up stimulation or top-down attention with the transfer condition. We found that either bottom-up or top-down influences enabled significant transfer of orientation and Vernier discrimination learning. These results suggest that learning specificity may result from under-activations of untrained visual neurons due to insufficient bottom-up stimulation and/or top-down attention during training. High-level perceptual learning thus may not functionally connect to these neurons for learning transfer.
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Human subjects: Informed consent, and consent to publish was obtained from each observer before testing. This study was approved by the Peking University Institution Review Board.
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© 2016, Xiong et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Bottom-up and top-down influences at untrained conditions determine perceptual learning specificity and transfer
eLife 5:e14614.
https://doi.org/10.7554/eLife.14614
Further reading
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