About Our Lab
We may take it for granted of our ability of speaking and listening in daily communication. Surprisingly, we know very little about the brain mechanism of this magic cycle of speech production and perception. Millions of people are suffering from hearing and communication disorder, hoping for innovative treatment and rehabilitation. In my lab, we are searching for the neural code of sound and speech representation in the brain. Collaborating with neurosurgeons, the speech network of the human brain and its neural code are investigated by using the neural activity from inside the patients’ brain, also known as intracranial EEG. With high temporal resolution of EEG and high spatial resolution of MRI, a picture of speaking and listening brain is emerging from the massive human brain data. Besides building a brain-computer interface for disabled patients, the neural circuits and codes that we are finding will surely be a crucial hint of developing a smarter speech recognition system, like Siri on your cell phone.
Neural mechanisms of human speech processing
The speech processing mechanisms (localization, connectivity and temporal dynamics) are investigated. Recently, we discovered a cooperative cortical network for categorical processing of lexical tone, the most important building block of tonal language, and revealed the surprising role of the motor cortex in the process (Si et al., 2017, PNAS). In the other direction, to improve the accuracy of pre-surgical mapping of language and motor functions and better outcome of neurosurgical patients, we developed methods of parcellating the cortical functional networks (Wang et al., 2015, Nature Neuroscience; Qian et al., 2013, Journal of Neurosurgery).
Next generation of BCI for communication
Based on our findings of neural encoding mechanisms and networks of the human brain, we invented a new BCI protocol and device which provides paralyzed patients with reliable and low-risk BCI communication, like typing and speaking with brain signals. My lab developed the first BCI typing protocol using visual motion response over human MT (Zhang et al., 2012 Journal of Neural Engineering), and a novel design of minimally invasive BCI using intracranial EEG (Zhang et al, 2013, NeuroImage). With collaboration from neurosurgeons, pre-clinical trials of implanted BCI have been carried out for paralyzed patients.