The basal ganglia have been implicated in a modulation role in idiopathic generalized epilepsy （IGE） by an invasive electrophysioigic means. This paper investigates the basal ganglia functional connectivity by using...The basal ganglia have been implicated in a modulation role in idiopathic generalized epilepsy （IGE） by an invasive electrophysioigic means. This paper investigates the basal ganglia functional connectivity by using the region-wise functional connection analysis in resting-state functional magnetic resonance imaging （fMRI） in IGE. The increased functional connectivity within basal ganglia, and between the basal ganglia and the thalamus, and decreased functional connectivity between basal ganglia and motor cortex are found in IGE compared with the controls. These findings not only implicate dysfunctional integration in the motor loop in IGE and the enhanced interaction in the modulated loop, but also suggest that the basal ganglia modulate the generalized epileptic discharges with the influence over thalamus in the corticothalamus network.展开更多
BACKGROUND： Previous studies have shown that lesions in the anterior limb of the internal capsule contribute to obsessive-compulsive symptoms in patients with refractory obsessive-compulsive disorder （OCD）. However...BACKGROUND： Previous studies have shown that lesions in the anterior limb of the internal capsule contribute to obsessive-compulsive symptoms in patients with refractory obsessive-compulsive disorder （OCD）. However, few reports have addressed the effects of lesions in the anterior limb of the internal capsule on cognition, learning, and memory functions in patients with refractory OCD. OBJECTIVE： To investigate the degree of damage to memory tasks in refractory OCD patients following lesions to the anterior limb of the internal capsule. DESIGN, TIME AND SETTING： A case-controlled, observational study was performed at the Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao-Tong University, China from May 2007 to March 2008. PARTICIPANTS： A total of 10 refractory OCD patients were admitted to the Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao-Tong University, China from May 2007 to March 2008 and were recruited for this study. The OCD patients were of equal gender, with an average age of （25.1 ± 9.6） years. An additional 10 healthy volunteers were enrolled from a community of Shanghai City as controls; they were of equal gender and aged （25.1 ± 8.6） years. METHODS： A total of 10 refractory OCD patients were subjected to lesions in the anterior limbs of the bilateral internal capsules. Wechsler Memory Scale-Chinese Revision （WMS-CR, as a task of explicit memory） and the Nissen Version （serial reaction time task） software （SRTT, as a task of implicit memory） were applied to determine memory functions and learning performance in pre- and post-operative OCD patients and controls. MAIN OUTCOME MEASURES： WMS scores, reaction time in SRTT, and Yale-Brown obsessive compulsive scale scores were measured in pre- and post-operative OCD patients and controls. RESULTS： Compared to controls, the pre-operative OCD patients exhibited reduced memory task scores （P = 0.005）, whereas scores for reciting numbers of backwards digits were greater （P = 0.000）. Figure recall and associative memory were less in OCD patients at 1 week following surgery than in the pre-operative OCD patients （P = 0.042, P = 0.002, respectively）. Reaction time in implicit SRTT was significantly longer in pre-operative OCD patients compared with controls and post-operative OCD patients （P = 0.01, P = 0.03, respectively）. These results suggested ameliorated SRTT following neurosurgery. Yale-Brown Obsessive Compulsive Scale results revealed significantly improved OCD following lesions in the internal capsule （P = 0.04）. Some post-operative OCD patients suffered from deficits in short-term memory and implicit memory. CONCLUSION： Lesions in anterior limbs of bilateral internal capsules improve obsessive- compulsive symptoms and implicit memory in OCD patients, but result in aggravated short-term memory deficits.展开更多
Once people have a well-trained motor skill, their performance becomes stabilized and achieving substantial improvement is difficult. Recently, we have shown that even a plateaued hand motor skill can be upgraded with...Once people have a well-trained motor skill, their performance becomes stabilized and achieving substantial improvement is difficult. Recently, we have shown that even a plateaued hand motor skill can be upgraded with short-period electrical stimulation to the hand prior to the task. Here, we identify the neuronal substrates underlying the improvement of the plateaued skill by examining the enhanced functional connectivity in the sensory-motor regions that are associated with motor learning. We measured brain activity using functional magnetic resonance imaging and performed psychophysiological interaction analysis. We recruited seven right-handed very-well trained participants, whose motor performance of continuously rotating two balls with their right hands became stabilized at higher performance levels. We prepared two experiments, in each of which they repeated an experimental run 16 times. In each run, they performed this cyclic rotation as many times as possible in 16 s. In the thenar-stimulation experiment, we applied 60-s stimulation to the thenar muscle before each of the 5th - 12th runs, and the others were preceded by ineffective sham stimulation. In the control experiment, the sham was always provided. Thenar stimulation enabled the participants to perform the movements at higher cycles. In association with this performance improvement, we found enhanced activity couplings between the primary motor cortex and the sensorimotor territory of the putamen and between the cerebellum and the primary sensorimotor cortices, without any quantitative activity increase. Neither behavioral change nor these increased activity couplings were observed in the control.Thus, in contrast to the stable neuronal states in the cortico-subcortical motor circuits when the well-learned task is repeated at the later stages of motor skill learning, plastic changes in the motor circuits seem to be required when the plateaued skill is upgraded, and the stimulation may entail a state of readiness for the plastic change that allows subsequent performance improvement.展开更多
基金supported by the National Natural Science Foundation of China under Grant No. 81071222
文摘The basal ganglia have been implicated in a modulation role in idiopathic generalized epilepsy （IGE） by an invasive electrophysioigic means. This paper investigates the basal ganglia functional connectivity by using the region-wise functional connection analysis in resting-state functional magnetic resonance imaging （fMRI） in IGE. The increased functional connectivity within basal ganglia, and between the basal ganglia and the thalamus, and decreased functional connectivity between basal ganglia and motor cortex are found in IGE compared with the controls. These findings not only implicate dysfunctional integration in the motor loop in IGE and the enhanced interaction in the modulated loop, but also suggest that the basal ganglia modulate the generalized epileptic discharges with the influence over thalamus in the corticothalamus network.
基金the Key Program of International Communication Foundation of Psychiatry and Neurology Department of Shanghai Jiao-Tong University, No. 200901
文摘BACKGROUND： Previous studies have shown that lesions in the anterior limb of the internal capsule contribute to obsessive-compulsive symptoms in patients with refractory obsessive-compulsive disorder （OCD）. However, few reports have addressed the effects of lesions in the anterior limb of the internal capsule on cognition, learning, and memory functions in patients with refractory OCD. OBJECTIVE： To investigate the degree of damage to memory tasks in refractory OCD patients following lesions to the anterior limb of the internal capsule. DESIGN, TIME AND SETTING： A case-controlled, observational study was performed at the Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao-Tong University, China from May 2007 to March 2008. PARTICIPANTS： A total of 10 refractory OCD patients were admitted to the Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao-Tong University, China from May 2007 to March 2008 and were recruited for this study. The OCD patients were of equal gender, with an average age of （25.1 ± 9.6） years. An additional 10 healthy volunteers were enrolled from a community of Shanghai City as controls; they were of equal gender and aged （25.1 ± 8.6） years. METHODS： A total of 10 refractory OCD patients were subjected to lesions in the anterior limbs of the bilateral internal capsules. Wechsler Memory Scale-Chinese Revision （WMS-CR, as a task of explicit memory） and the Nissen Version （serial reaction time task） software （SRTT, as a task of implicit memory） were applied to determine memory functions and learning performance in pre- and post-operative OCD patients and controls. MAIN OUTCOME MEASURES： WMS scores, reaction time in SRTT, and Yale-Brown obsessive compulsive scale scores were measured in pre- and post-operative OCD patients and controls. RESULTS： Compared to controls, the pre-operative OCD patients exhibited reduced memory task scores （P = 0.005）, whereas scores for reciting numbers of backwards digits were greater （P = 0.000）. Figure recall and associative memory were less in OCD patients at 1 week following surgery than in the pre-operative OCD patients （P = 0.042, P = 0.002, respectively）. Reaction time in implicit SRTT was significantly longer in pre-operative OCD patients compared with controls and post-operative OCD patients （P = 0.01, P = 0.03, respectively）. These results suggested ameliorated SRTT following neurosurgery. Yale-Brown Obsessive Compulsive Scale results revealed significantly improved OCD following lesions in the internal capsule （P = 0.04）. Some post-operative OCD patients suffered from deficits in short-term memory and implicit memory. CONCLUSION： Lesions in anterior limbs of bilateral internal capsules improve obsessive- compulsive symptoms and implicit memory in OCD patients, but result in aggravated short-term memory deficits.
文摘Once people have a well-trained motor skill, their performance becomes stabilized and achieving substantial improvement is difficult. Recently, we have shown that even a plateaued hand motor skill can be upgraded with short-period electrical stimulation to the hand prior to the task. Here, we identify the neuronal substrates underlying the improvement of the plateaued skill by examining the enhanced functional connectivity in the sensory-motor regions that are associated with motor learning. We measured brain activity using functional magnetic resonance imaging and performed psychophysiological interaction analysis. We recruited seven right-handed very-well trained participants, whose motor performance of continuously rotating two balls with their right hands became stabilized at higher performance levels. We prepared two experiments, in each of which they repeated an experimental run 16 times. In each run, they performed this cyclic rotation as many times as possible in 16 s. In the thenar-stimulation experiment, we applied 60-s stimulation to the thenar muscle before each of the 5th - 12th runs, and the others were preceded by ineffective sham stimulation. In the control experiment, the sham was always provided. Thenar stimulation enabled the participants to perform the movements at higher cycles. In association with this performance improvement, we found enhanced activity couplings between the primary motor cortex and the sensorimotor territory of the putamen and between the cerebellum and the primary sensorimotor cortices, without any quantitative activity increase. Neither behavioral change nor these increased activity couplings were observed in the control.Thus, in contrast to the stable neuronal states in the cortico-subcortical motor circuits when the well-learned task is repeated at the later stages of motor skill learning, plastic changes in the motor circuits seem to be required when the plateaued skill is upgraded, and the stimulation may entail a state of readiness for the plastic change that allows subsequent performance improvement.
