Effect of reward alteration following acupuncture for morphine withdrawal rats on neuronal discharges in the ventral medial prefrontal cortex

Objective：To observe the effect of reward alteration following acupuncture for morphine withdrawal rats on the behavior and neuronal discharges in the medial prefrontal cortex （mPFC）. Methods：The Sprague-Dawley （SD） rats were randomly allocated into a model group, a confinement group, an electroacupuncture （EA） group, and a control group. Rats with morphine addiction were made by intraperitoneal injection of naloxone （same dose injection of saline for rats in the control group）, followed by a 2-week morphine withdrawal. Acupuncture and confinement were completed during the morphine withdrawal period. Upon withdrawal, the rats received conditioned place preference （CPP） training and open field test. The multi-channel neural signal processor was used in the electrophysiological experiment to measure the neuronal discharges in different subareas of prefrontal cortex in CPP box and aversion box. Results：Rats in the model group and the confinement group spent longer period of time in CPP box than those in the EA group and the control group （allP〈0.01）; there was no statistically significant difference between the EA group and the control group. The total distances of movement by rats in the model group and the confinement group were longer than those in the EA group and the control group （allP〈0.01）. The mPFC neuronal discharge frequencies were compared between morphine preference box and aversion box. The mPFC neuronal discharge frequencies in the model group and the confinement group were higher than those in the EA group and the control group （allP〈0.05）; there was no statistically significant difference between the EA group and the control group. Conclusion：Acupuncture can effectively interfere with the reward alteration following morphine withdrawal, possibly because of its involvement with the mPFC neuronal discharges.

Ventral medial prefrontal functional connectivity and emotion regulation in chronic schizophrenia: A pilot study

People with schizophrenia exhibit impaired social cognitive functions, particularly emotion regulation. Abnormal activations of the ventral medial prefrontal cortex （vMPFC） during emotional tasks have been demonstrated in schizophrenia, suggesting its important role in emotion processing in patients. We used the resting-state functional connectivity approach, setting a functionally relevant region, the vMPFC, as a seed region to examine the intrinsic functional interactions and communication between the vMPFC and other brain regions in schizophrenic patients. We found hypo-connectivity between the vMPFC and the medial frontal cortex, right middle temporal lobe （MTL）, right hippocampus, parahippocampal cortex （PHC） and amygdala. Further, there was a decreased strength of the negative connectivity （or anticorrelation） between the vMPFC and the bilateral dorsal lateral prefrontal cortex （DLPFC） and pre-supplementary motor areas. Among these connectivity alterations, reduced vMPFC-DLPFC connectivity was positively correlated with positive symptoms on the Positive and Negative Syndrome Scale, while vMPFC-right MTL/PHC/amygdala functional connectivity was positively correlated with the performance of emotional regulation in patients. These findings imply that communication and coordination throughout the brain networks are disrupted in schizophrenia. The emotional correlates of vMPFC connectivity suggest a role of the hypo-connectivity between these regions in the neuropathology of abnormal social cognition in chronic schizophrenia.