Cooperative cortical network for categorical processing of Chinese lexical tone

This dataset contains the ECoG, CT and MRI data for the six subjects associated with the manuscript, "Cooperative cortical network for categorical processing of Chinese lexical tone", as well as stimulus sound files used in the study.

data_MRI.rar  - MRI scan before the ECoG electrode implantation

data_CT.rar  -  CT images with ECoG electrode implanted

data_ECoG.rar - ECoG recording of six patients reported in the manuscript

stimuli_BehaviorContinumm.rar  - Chinese tone continuum stimuli (Token 1-13 as in Fig 1 of the manuscript)

stimuli_ECoG_MMN.rar - Chinese tone stimuli used for oddball paradigm in ECoG experiment (Token 2, 5 and 8, see Fig 1 of the manuscript)

Upon email request (hongbo@tsinghua.edu.cn), the authors may provide analysis code. 

Original manuscript:

Si, Zhou and Hong. PNAS, 2017

Cooperative cortical network for categorical processing of Chinese lexical tone

Abstract: In tonal languages such as Chinese, lexical tone with varying pitch contours serves as a key feature to provide contrast in word meaning. Similar to phoneme processing, behavioral studies have suggested that Chinese tone is categorically perceived. However, its underlying neural mechanism remains poorly understood. By conducting cortical surface recordings in surgical patients, we revealed a cooperative cortical network along with its dynamics responsible for this categorical perception. Based on an oddball paradigm, we found amplified neural dissimilarity between cross-category tone pairs, rather than between within-category tone pairs, over cortical sites covering both the ventral and dorsal streams of speech processing. The bilateral superior temporal gyrus (STG) and the middle temporal gyrus (MTG) exhibited increased response latencies and enlarged neural dissimilarity, suggesting a ventral hierarchy that gradually differentiates the acoustic features of lexical tones. In addition, the bilateral motor cortices were also found to be involved in categorical processing, interacting with both the STG and the MTG and exhibiting a response latency in between. Moreover, the motor cortex received enhanced Granger causal influence from the semantic hub, the anterior temporal lobe, in the right hemisphere. These unique data suggest that there exists a distributed cooperative cortical network supporting the categorical processing of lexical tone in tonal language speakers, not only encompassing a bilateral temporal hierarchy that is shared by categorical processing of phonemes but also involving intensive speech-motor interactions over the right hemisphere, which might be the unique machinery responsible for the reliable discrimination of tone identities.