https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Asymmetric compression of representational space for object animacy categorization under degraded viewing conditions https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34068 PLoS Computational Biology, 11, e1004316, 2015; Carlson, T. A., Ritchie, J. B., Kriegeskorte, N., Durvasula, S., & Ma, J. Reaction time for object categorization is predicted by representational distance. Journal of Cognitive Neuroscience, 26, 132–142, 2014]. Using MEG decoding, we tested if the same relationship holds when a stimulus manipulation (degradation) increases task difficulty, which we predicted would systematically decrease the distance of activation patterns from the decision boundary and increase RTs. In addition, we tested whether distance to the classifier boundary correlates with drift rates in the linear ballistic accumulator [Brown, S. D., & Heathcote, A. The simplest complete model of choice response time: Linear ballistic accumulation. Cognitive Psychology, 57, 153–178, 2008]. We found that distance to the classifier boundary correlated with RT, accuracy, and drift rates in an animacy categorization task. Split by animacy, the correlations between brain and behavior were sustained longer over the time course for animate than for inanimate stimuli. Interestingly, when examining the distance to the classifier boundary during the peak correlation between brain and behavior, we found that only degraded versions of animate, but not inanimate, objects had systematically shifted toward the classifier decision boundary as predicted. Our results support an asymmetry in the representation of animate and inanimate object categories in the human brain.]]> Tue 03 Sep 2019 18:27:13 AEST ]]> Linking cognitive and reaching trajectories via intermittent movement control https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20064 Sat 24 Mar 2018 08:00:12 AEDT ]]>