Study Of Dynamic Neural State Coding And Neuropathic Pain Mechanism In Deep Brain Nuclei

Chronic neuropathic pain not only a persistent pain,but also causes abnormal pain sensory,emotion,and cognition,which seriously affects the life quality of patients.However,the mechanism of neuropathic pain is still unclear,and there is a lack of research on how the advanced cognitive function,such as emotion and cognitive changes after neuropathic pain.The sensory thalamus and periventricular gray/periaqueductal gray(PVAG)are not only closely related to pain perception but also common targets for deep brain stimulation(DBS)in the treatment of neuropathic pain.Previous studies based on local field potentials(LFPs)have shown that there are neural oscillations in the two nuclei associated with the pain perception and its neuromulation for patients,and suggest that the dynamic integration of neural oscillations might be the real way of human brain encodes pain information.Therefore,study the relationship between the dynamic integration of multiple neural oscillations within or between deep brain nuclei and neuropathic pain could help to further reveal the mechanism of neuropathic pain in perception,sensory and affective dimensions,and provide a new direction for pain disgosis and treatment.Based on such background,this study focuses on patients with neuropathic pain who treated with DBS.The pre-operative pain state including pain intensity,sensory and affective of each subject was evaluated and his/her pain relief after DBS surgery were monitored.At the same time,LFPs of the sensory thalamus and PVAG before stimulation were recorded.Then four scientific questions were explored in this study.(1)How the human brain dynamically integrates multiple neural oscillations to deliver brain function.(2)How the sensory thalamus integrates neural oscillations to encode neuropathic pain perception and its modulation.(3)How the PVAG integrates neural oscillations to encode pain intensity,sensory and affective at the same time.(4)Whether there is a functional connection between the sensory thalamus and the PVAG to realized pain information transmission and integration.The main findings of this study are as follows.(1)Dynamic integration of multiple oscillations may be an important way of the brain encode functional information.Moreover,results indicated that information encoded in this way has a closer correlation with neuropathic pain.(2)There are two distinct oscillatory networks in" the sensory thalamus for pain perception and pain modulation.One network of neural oscillations with low-beta oscillation as the key element is involved in pain modulation,and the other with delta oscillation as the key element is involved in pain perception.(3)The PVAG has involved in the coding of pain intensity,sensory and affective,simultaneously.Furthermore,in the PVAG,an oscillatory network centered on delta oscillation is responses for encoding pain intensity,an oscillatory network centered on high-gamma oscillation is responses for pain sensory,while another oscillatory network involved alpha and high-beta oscillations responses for pain affective.(4)There are significant functional connections between the sensory thalamus and the PVAG.And these connections are involved in the transmission and integration of neuropathic pain multiple information within the brain network.In summary,this study systematically-explored how the sensory thalamus and PVAG nuclei encode the multi-dimensional information of pain by manipulating multiple neural oscillations.The results of this study advance the study of neuropathic pain and its neuromodulation mechanisms,which will help the development of intelligent neurological diagnosis and neruomodulation strategies for neuropathic pain in the future.