Bridging Working Memory and Imagery: Encoding induced alpha EEG activity reveals similar neural processes

[摘要] While both imagery and visual working memory address the mental representation of visual information, it remains unclear whether the representations of information during these processes are mediated by similar mechanisms. Albers et al. (2012) were able to demonstrate that working memory representations can be identified and tracked down during a mental imagery rotation by decoding fMRI activity detected in the primary visual cortex. A recent study by Foster et al. (2016) reported that it is possible to identify the feature of an object held in working memory by applying an encoding model on induced alpha activity (8-15Hz). In an attempt to determine the similarities between imagery and working memory, we replicated Foster et al. (2016) and extended their findings by investigating the behavioural and neural properties imagery. A forward encoding model was applied to EEG activity recorded while participants were holding the orientation of a stimulus in working memory and then transformed through a mental rotation of 60°. The reconstruction of orientation selectivity profiles revealed the orientation of the working memory representation and reliable changes in the mental representation during the imagery manipulation. Furthermore, the behavioural results indicate that the level of precision in the report of the transformed orientation feature is comparable with typical working memory precision. These results suggest that visual working memory and imagery share similar neural and behavioural mechanisms.

[学科分类] 眼科学