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The ventrobasal complex ("'VB"') is a relay nucleus of the thalamus for nociceptive stimuli received from nociceptive nerves. The VB consists of the Ventral posteromedial nucleus (VPM) and the Ventral posterolateral nucleus (VPL). In some species the ventral posterolateral nucleus, pars caudalis is also a part of the VB.〔Natsu Koyama, Yasuo Nishikawa, Toshikatsu Yokota. Distribution of nociceptive neurons in the ventrobasal complex of macaque thalamus. Neuroscience Research 31 (1998) 39-51.〕 The VB gets inputs from the Spinothalamic tract, Medial lemniscus, and corticothalamic tract.〔W.D. Willis Jr. et al. Projections from the marginal zone and deep dorsal horn to the ventrobasal nuclei of the primate thalamus. Pain 92 (2001) 267-276.〕〔Yasuyuki Nagumo, Yuichi Takeuchi, Keiji Imoto, Mariko Miyata. Synapse- and subtype-specific modulation of synaptic transmission by nicotinic acetylcholine receptrs in the ventrobasal thalamus. Neuroscience Research 69 (2011) 203-213.〕 The main output of the VB is the primary somatosensory cortex. The VB serves as the main relay for nociceptive stimuli and the modulation of that stimuli to the primary somatosensory cortex. The modulation occurs through different types of receptors present in the VB. ==VB Inputs== Spinothalamic Tract (STT) cells that project from laminae I and V in the lumbrosacral area of the spinal cord project to the VPL in the VB.〔 STT cells located in the cervical area of the spinal cord are the densest and project from the neck of the dorsal horn to the VPL of the VB. Most projections to the VB are contralateral while only a few projections to the VB are ipsilateral.〔 Excitatory inputs to the VB are medial lemniscal (ML) and corticothalamic (CT) glutamatergic synapses. The ML is a sensory afferent input and the CT is from layer VI of the primary sensory cortex.〔 The VB also gets inputs from areas in the brain stem which release Acetylcholine (ACh) that can modulate activity in the VB.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ventrobasal complex」の詳細全文を読む スポンサード リンク
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