The orbitofrontal cortex （OFC） is particularly important for the neural representation of reward value. Previous studies indicated that electroencephalogram （EEG） activity in the OFC was involved in drug administr...The orbitofrontal cortex （OFC） is particularly important for the neural representation of reward value. Previous studies indicated that electroencephalogram （EEG） activity in the OFC was involved in drug administration and withdrawal. The present study investigated EEG activity in the OFC in rats during the development of food reward and craving. Two environments were used separately for control and food-related EEG recordings. In the food-related environment rats were first trained to eat chocolate peanuts; then they either had no access to this food, but could see and smell it （craving trials）, or had free access to this food （reward trials）. The EEG in the left OFC was recorded during these trials. We showed that, in the food-related environment the EEG activity peaking in the delta band （2-4 Hz） was significantly correlated with the stimulus, increasing during food reward and decreasing during food craving when compared with that in the control environment. Our data suggests that EEG activity in the OFC can be altered by food reward; moreover, delta rhythm in this region could be used as an index monitoring changed signal underlying this reward.展开更多
The prefrontal cortex(PFC)is thought to be involved in higher order cognitive functions,such as in working memory,abstract categorization,and reward processing.It has been reported that two distinct neuron classes(put...The prefrontal cortex(PFC)is thought to be involved in higher order cognitive functions,such as in working memory,abstract categorization,and reward processing.It has been reported that two distinct neuron classes(putative pyramidal cells and interneurons)in the PFC played different functional roles in neural circuits involved in forming working memory and abstract categories.However,it remains elusive how the two types of neurons process reward information in the PFC.To investigate this issue,the activity of single neurons was extracellularly recorded in the PFC of the monkey performing a reward predicting task.PFC neurons were classified into putative pyramidal cells and interneurons,respectively,based on the waveforms of action potentials.Both the two types of neurons encoded reward information and discriminated two reward conditions(the preferred reward condition vs.the nonpreferred reward condition).However,the putative pyramidal neurons had better and more reliable discriminability than the putative interneurons.Also,the pyramidal cells represented reward information in the preferred reward condition,but not in the nonpreferred reward condition by raising their firing rates relative to the baseline rates.In contrast,the interneurons encoded reward information in the nonpreferred reward condition,but not in the preferred reward condition by inhibiting their discharge rates relative to the baseline rates.These results suggested that the putative pyramidal cells and interneurons had complementary functions in reward processing.These findings may help to clarify individual functions of each type of neurons in PFC neuronal circuits involved in reward processing.展开更多
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 ...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.展开更多
基金National Science Foundation of China (3047055330530270+10 种基金30670669 30770700)973 Program (2005CB522803 2007CB947703)863 Program (O7013810 2006AA02A116)The Major State Basic Research of China (2003CB716600)Chinese-Finnish International Collaboration Project-neuro (30621130076)Program of CASC (KSCX1-YW-R-33YZ200737)National Key Technologies R & D Program and Yunnan Science and Technique Program (2006PT08-2)
文摘The orbitofrontal cortex （OFC） is particularly important for the neural representation of reward value. Previous studies indicated that electroencephalogram （EEG） activity in the OFC was involved in drug administration and withdrawal. The present study investigated EEG activity in the OFC in rats during the development of food reward and craving. Two environments were used separately for control and food-related EEG recordings. In the food-related environment rats were first trained to eat chocolate peanuts; then they either had no access to this food, but could see and smell it （craving trials）, or had free access to this food （reward trials）. The EEG in the left OFC was recorded during these trials. We showed that, in the food-related environment the EEG activity peaking in the delta band （2-4 Hz） was significantly correlated with the stimulus, increasing during food reward and decreasing during food craving when compared with that in the control environment. Our data suggests that EEG activity in the OFC can be altered by food reward; moreover, delta rhythm in this region could be used as an index monitoring changed signal underlying this reward.
基金supported by Grant-in-aid for Scientific Research on Innovative Areas,Grant-in-aid for Scientific Research(A),and Tamagawa Global Center of Excellence,Japanthe National Natural Science Foundation of China(Grant No.11232005)+1 种基金the Fundamental Research Funds for the Central Universities of ChinaShanghai Pujiang Program(Grant No.13PJ1402000)
文摘The prefrontal cortex(PFC)is thought to be involved in higher order cognitive functions,such as in working memory,abstract categorization,and reward processing.It has been reported that two distinct neuron classes(putative pyramidal cells and interneurons)in the PFC played different functional roles in neural circuits involved in forming working memory and abstract categories.However,it remains elusive how the two types of neurons process reward information in the PFC.To investigate this issue,the activity of single neurons was extracellularly recorded in the PFC of the monkey performing a reward predicting task.PFC neurons were classified into putative pyramidal cells and interneurons,respectively,based on the waveforms of action potentials.Both the two types of neurons encoded reward information and discriminated two reward conditions(the preferred reward condition vs.the nonpreferred reward condition).However,the putative pyramidal neurons had better and more reliable discriminability than the putative interneurons.Also,the pyramidal cells represented reward information in the preferred reward condition,but not in the nonpreferred reward condition by raising their firing rates relative to the baseline rates.In contrast,the interneurons encoded reward information in the nonpreferred reward condition,but not in the preferred reward condition by inhibiting their discharge rates relative to the baseline rates.These results suggested that the putative pyramidal cells and interneurons had complementary functions in reward processing.These findings may help to clarify individual functions of each type of neurons in PFC neuronal circuits involved in reward processing.
基金supported by National Natural Science Foundation of China No.81373753Natural Science Foundation of Shanghai No.13ZR1441900the Budgeted Scientific Research Project of Shanghai University of Traditional Chinese Medicine No.2013JW16~~
文摘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.
