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The medial prefrontal cortex controls dopamine-induced motor behavior via the subthalamic nucleus activation
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Abstracts / Neuroscience Research 58S (2007) S1–S244
O2P-E11 Role of the primate lateral habenula in negative moti-
O2P-FØ2 EEG phase synchronizaion during attentional blink
vational control of behavior Masayuki Matsumoto, Okihide Hikosaka Laboratory of Sensorimotor Research, NEI, NIH, USA
Chie Nakatani, Cees Van Leeuwen Laboratory for Perceptual Dynamics, Brain Science Institute, RIKEN, Japan
Animal behaviors are facilitated by expectation of big reward and suppressed by expectation of small or no reward. Midbrain dopamine (DA) neurons are thought to be involved in such reward-based control of motor behavior. However, it is unclear which parts of the brain provide DA neurons with signals necessary for the action. We tested the hypothesis that projections from the lateral habenula (LHb) transmit reward-related signals to DA neurons. First, we recorded the activity of LHb and DA neurons while monkeys were performing a visually guided saccade task with positional reward bias. LHb neurons were predominantly excited by a noreward-predicting target and inhibited by a reward-predicting target. In contrast, DA neurons were excited and inhibited by reward and noreward-predicting targets, respectively. The LHb excitation started earlier than the DA inhibition. Second, we examined the effect of electrical stimulation of the LHb on the activity of DA neurons. The stimulation elicited strong inhibitions in DA neurons. Our results suggest that the LHb suppresses less rewarding motor behavior by inhibiting DA neurons.
A target presented in a rapid stimulus sequence (∼10 items/sec.) usually is detected easily. However, when two targets (T1 and T2) are presented in sequence, T2 is often missed when the two are 200–500 ms apart. This phenomenon is called attentional blink. Brain activities that correlate with attentional blink (AB) phenomenon were reported before, around, and after the targets. Before T1 onset, EEG phase synchronization in the ␥ band increases when T2 is detected. Around T1 and T2,  band MEG and ␥ band EEG phase synchronization increased when T2 is detected. After T2, studies using ERP technique suggest that synchrony in lower bands, such as to ␦ bands. In the current study, we analyzed EEG during AB task using dynamic cross-lag phase synchronization index from ␦ to ␥ bands. In all bands, epochs of large-scale synchronization is observed when T2 was detected in AB condition. Timing of the synchronization varied; before T1 onset, the synchronization was observed in all bands. Around T1, it was observed in  band. After T2 onset, a large-scale synchronization in band proceeded that in ␦ band.
O2P-E12 The medial prefrontal cortex controls dopamineinduced motor behavior via the subthalamic nucleus activation
O2P-FØ3 Interaction between noise and pattern in vision
Yasunobu Yasoshima, Kazuto Kobayashi Department of Molecular Genetics, Fukushima Medical University, Fukushima, Japan Microinjection of GABAA receptor agonist muscimol into the medial prefrontal cortex (mPFC) suppresses both hyperlocomotion and activation of c-fos gene in the subthalamic nucleus (STN) induced by dopaminergic stimulation. These reactions are mediated by dopamine D1-like and D2-like receptors in the mPFC. The present study examined the role of the mPFC-STN pathway in dopamine-induced hyperlocomotion. When a retrograde tracer FluoroGold (FG) was injected into the STN, the labeled pyramidal cells were found in the mPFC. Intra-mPFC injection of biotinylated dextran amine gave anterogradely labeled fibers in the STN. Systemic injection of methamphetamine (METH) elicited c-fos expression in glutamatergic, but not GABAergic, mPFC neurons. Some of c-fos-positive mPFC neurons were also labeled by FG injected into the STN, indicating that some METH-activated mPFC projection neurons monosynaptically innervate the STN. These results suggest that the mPFC neurons facilitates dopamine-induced hyperlocomotion via the corticosubthalamic pathway.
Sohei Wakisaka Faculty of Science, Kobe University, Hyogo, Japan When two eyes see radically different images simultaneously, the images compete in visual perception The homogeneous field scarcely rivals a highly patterned image and the vision under “one” eyelid (i.e. a closed eye) is therefore not usually perceived, or at most is perceived as intrinsic dynamic visual noise only noticeable with careful inspection. However, recent studies revealed that activity of the primary visual cortex with both eyes closed is actually patterned as if an oriented stimulus were presented. Then, what happens between ongoing activities and those induced by oriented stimulus? Here we show a novel visual phenomenon, Diagonal Mesh Pattern (DMP), in which visual noise rivals an oriented stimulus but at the same time is spatio-temporally highly modulated by them. The main characteristic of DMP is a noisy mesh pattern diagonally intersecting each point of the repetitive pattern. DMP shows that the figural information of the suppressed stimulus surprisingly survives rivalry, to the extent that it conflicts with the very definition of BR. We “see” interocular interaction in the early visual process through DMP. We also propose a simple explanatory model.
Research funds: KAKENHI (18500244)
O2P-E13 Abnormal oscillatory discharges of basal ganglia neurons in parkinsonian monkeys
O2P-FØ4 Mental rotation of hands and feet involves somato-
Yoshihisa Tachibana 1,2 , Hirokazu Iwamuro 1,3 , Masahiko Takada 4 , Atsushi Nambu 1,2 1 Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Japan; 2 SOKENDAI, Hayama, Japan; 3 Department of Neurosurgery, University of Tokyo, Tokyo, Japan; 4 Department of System Neuroscience, Tokyo Metropolitan Institute for Neuroscience, Fuchu, Japan
Takashi Hanakawa, Chihiro Hosoda, Seigo Shindo, Manabu Honda Department of Cortical Function Disorders, NIN, NCNP, Kodaira, Japan
Classical models concerning the pathophysiology suggest that Parkinson’s disease is induced by the changes in the firing rates of basal ganglia neurons following loss of dopaminergic neurons from the substantia nigra. However, recent emphasis has been placed on the abnormal firing patterns of basal ganglia neurons, such as oscillation and bursting. In our primate model of Parkinson’s disease, abnormal oscillatory discharges were so often observed in the globus pallidus and the subthalamic nucleus, as compared to normal controls. Muscimol inactivation of the subthalamic nucleus eliminated the abnormal oscillations from the globus pallidus, and vice versa. These results indicate that the abnormal oscillatory discharges of basal ganglia neurons seen in Parkinson’s disease may be facilitated by the neuronal interactions between the globus pallidus and the subthalamic nucleus. Research funds: KAKENHI (18300135) and JAPAN INTRACTABLE DISEASES RESEARCH FOUNDATION
topically organized brain regions
Some cognitive functions are implied to rely on motor strategies, but previous studies have produced conflicting results as for the roles of the motor cortex in the mental rotation of body parts. We readdressed this issue by investigating brain activity during mental rotation of body parts along with various motor control tasks. Sixteen healthy volunteers were scanned with a 3-T MRI after a 30-min training session. Typical effects of rotation angles on reaction time were evident. During fMRI scanning, they perfomed mental rotation of hands and feet presented visually. In comparison with the foot rotation task, the hand rotation task activated lateral premotor cortex, occupying the rostral part of the activity for the hand movement task. Conversely, the foot rotation task involved supplementary motor areas and bilateral medial central zones at the border of primary motor cortex and somatosensory cortex. The present results support the involvement of somatotopically organized brain areas for mental rotation of body parts. Research funds: KAKENHI (17500210)
Abstracts / Neuroscience Research 58S (2007) S1–S244
O2P-E11 Role of the primate lateral habenula in negative moti-
O2P-FØ2 EEG phase synchronizaion during attentional blink
vational control of behavior Masayuki Matsumoto, Okihide Hikosaka Laboratory of Sensorimotor Research, NEI, NIH, USA
Chie Nakatani, Cees Van Leeuwen Laboratory for Perceptual Dynamics, Brain Science Institute, RIKEN, Japan
Animal behaviors are facilitated by expectation of big reward and suppressed by expectation of small or no reward. Midbrain dopamine (DA) neurons are thought to be involved in such reward-based control of motor behavior. However, it is unclear which parts of the brain provide DA neurons with signals necessary for the action. We tested the hypothesis that projections from the lateral habenula (LHb) transmit reward-related signals to DA neurons. First, we recorded the activity of LHb and DA neurons while monkeys were performing a visually guided saccade task with positional reward bias. LHb neurons were predominantly excited by a noreward-predicting target and inhibited by a reward-predicting target. In contrast, DA neurons were excited and inhibited by reward and noreward-predicting targets, respectively. The LHb excitation started earlier than the DA inhibition. Second, we examined the effect of electrical stimulation of the LHb on the activity of DA neurons. The stimulation elicited strong inhibitions in DA neurons. Our results suggest that the LHb suppresses less rewarding motor behavior by inhibiting DA neurons.
A target presented in a rapid stimulus sequence (∼10 items/sec.) usually is detected easily. However, when two targets (T1 and T2) are presented in sequence, T2 is often missed when the two are 200–500 ms apart. This phenomenon is called attentional blink. Brain activities that correlate with attentional blink (AB) phenomenon were reported before, around, and after the targets. Before T1 onset, EEG phase synchronization in the ␥ band increases when T2 is detected. Around T1 and T2,  band MEG and ␥ band EEG phase synchronization increased when T2 is detected. After T2, studies using ERP technique suggest that synchrony in lower bands, such as to ␦ bands. In the current study, we analyzed EEG during AB task using dynamic cross-lag phase synchronization index from ␦ to ␥ bands. In all bands, epochs of large-scale synchronization is observed when T2 was detected in AB condition. Timing of the synchronization varied; before T1 onset, the synchronization was observed in all bands. Around T1, it was observed in  band. After T2 onset, a large-scale synchronization in band proceeded that in ␦ band.
O2P-E12 The medial prefrontal cortex controls dopamineinduced motor behavior via the subthalamic nucleus activation
O2P-FØ3 Interaction between noise and pattern in vision
Yasunobu Yasoshima, Kazuto Kobayashi Department of Molecular Genetics, Fukushima Medical University, Fukushima, Japan Microinjection of GABAA receptor agonist muscimol into the medial prefrontal cortex (mPFC) suppresses both hyperlocomotion and activation of c-fos gene in the subthalamic nucleus (STN) induced by dopaminergic stimulation. These reactions are mediated by dopamine D1-like and D2-like receptors in the mPFC. The present study examined the role of the mPFC-STN pathway in dopamine-induced hyperlocomotion. When a retrograde tracer FluoroGold (FG) was injected into the STN, the labeled pyramidal cells were found in the mPFC. Intra-mPFC injection of biotinylated dextran amine gave anterogradely labeled fibers in the STN. Systemic injection of methamphetamine (METH) elicited c-fos expression in glutamatergic, but not GABAergic, mPFC neurons. Some of c-fos-positive mPFC neurons were also labeled by FG injected into the STN, indicating that some METH-activated mPFC projection neurons monosynaptically innervate the STN. These results suggest that the mPFC neurons facilitates dopamine-induced hyperlocomotion via the corticosubthalamic pathway.
Sohei Wakisaka Faculty of Science, Kobe University, Hyogo, Japan When two eyes see radically different images simultaneously, the images compete in visual perception The homogeneous field scarcely rivals a highly patterned image and the vision under “one” eyelid (i.e. a closed eye) is therefore not usually perceived, or at most is perceived as intrinsic dynamic visual noise only noticeable with careful inspection. However, recent studies revealed that activity of the primary visual cortex with both eyes closed is actually patterned as if an oriented stimulus were presented. Then, what happens between ongoing activities and those induced by oriented stimulus? Here we show a novel visual phenomenon, Diagonal Mesh Pattern (DMP), in which visual noise rivals an oriented stimulus but at the same time is spatio-temporally highly modulated by them. The main characteristic of DMP is a noisy mesh pattern diagonally intersecting each point of the repetitive pattern. DMP shows that the figural information of the suppressed stimulus surprisingly survives rivalry, to the extent that it conflicts with the very definition of BR. We “see” interocular interaction in the early visual process through DMP. We also propose a simple explanatory model.
Research funds: KAKENHI (18500244)
O2P-E13 Abnormal oscillatory discharges of basal ganglia neurons in parkinsonian monkeys
O2P-FØ4 Mental rotation of hands and feet involves somato-
Yoshihisa Tachibana 1,2 , Hirokazu Iwamuro 1,3 , Masahiko Takada 4 , Atsushi Nambu 1,2 1 Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Japan; 2 SOKENDAI, Hayama, Japan; 3 Department of Neurosurgery, University of Tokyo, Tokyo, Japan; 4 Department of System Neuroscience, Tokyo Metropolitan Institute for Neuroscience, Fuchu, Japan
Takashi Hanakawa, Chihiro Hosoda, Seigo Shindo, Manabu Honda Department of Cortical Function Disorders, NIN, NCNP, Kodaira, Japan
Classical models concerning the pathophysiology suggest that Parkinson’s disease is induced by the changes in the firing rates of basal ganglia neurons following loss of dopaminergic neurons from the substantia nigra. However, recent emphasis has been placed on the abnormal firing patterns of basal ganglia neurons, such as oscillation and bursting. In our primate model of Parkinson’s disease, abnormal oscillatory discharges were so often observed in the globus pallidus and the subthalamic nucleus, as compared to normal controls. Muscimol inactivation of the subthalamic nucleus eliminated the abnormal oscillations from the globus pallidus, and vice versa. These results indicate that the abnormal oscillatory discharges of basal ganglia neurons seen in Parkinson’s disease may be facilitated by the neuronal interactions between the globus pallidus and the subthalamic nucleus. Research funds: KAKENHI (18300135) and JAPAN INTRACTABLE DISEASES RESEARCH FOUNDATION
topically organized brain regions
Some cognitive functions are implied to rely on motor strategies, but previous studies have produced conflicting results as for the roles of the motor cortex in the mental rotation of body parts. We readdressed this issue by investigating brain activity during mental rotation of body parts along with various motor control tasks. Sixteen healthy volunteers were scanned with a 3-T MRI after a 30-min training session. Typical effects of rotation angles on reaction time were evident. During fMRI scanning, they perfomed mental rotation of hands and feet presented visually. In comparison with the foot rotation task, the hand rotation task activated lateral premotor cortex, occupying the rostral part of the activity for the hand movement task. Conversely, the foot rotation task involved supplementary motor areas and bilateral medial central zones at the border of primary motor cortex and somatosensory cortex. The present results support the involvement of somatotopically organized brain areas for mental rotation of body parts. Research funds: KAKENHI (17500210)