最近的大脑连接体研究证明了处理嗅觉感知所涉及的不同和重叠的大脑区域。然而,嗅觉障碍患者的嗅觉减退或嗅觉减退的神经相关性尚不清楚。此外,嗅觉感知的自下而上和自上而下的处理还没有得到很好的记录,导致难以定位嗅觉障碍患者的疾病病灶。这项研究的主要目的是表征麻醉小鼠周围和中央大脑区域的神经动力学自下而上的过程。我们特别关注嗅觉上皮(OE)中局部场电位(LFP)的神经振荡,嗅觉蓝(OB),前额叶皮质(PFC),和海马(HC)在氨酯麻醉小鼠的嗅觉怪球范例中。气味表现诱发神经振荡,包括delta(1-4Hz)在内的慢速和快速频段,θ(6-10Hz),β(15-30Hz),低伽马(30-50Hz),和高伽马(70-100赫兹)在周围和中枢神经系统,在不常见的气味剂中,这种增加更为突出。在5s气味暴露期间,功率的振荡反应在OE中是持续的,OB,和PFC,而HC的神经振荡在刺激开始时仅在短时间内增加。这些功率振荡响应在ZnSO4处理的无嗅觉模型的外围和中心区域均不明显。这些结果表明,嗅觉刺激会在周围和中枢神经系统中引起LFP振荡,并暗示大脑中的LFP振荡与周围嗅觉系统中的振荡相关联的可能性。
Recent brain connectome studies have evidenced distinct and overlapping brain regions involved in processing olfactory perception. However, neural correlates of hypo- or anosmia in olfactory disorder patients are poorly known. Furthermore, the bottom-up and top-down processing of olfactory perception have not been well-documented, resulting in difficulty in locating the disease foci of olfactory disorder patients. The primary aim of this study is to characterize the bottom-up process of the neural dynamics across peripheral and central brain regions in anesthetized mice. We particularly focused on the neural oscillations of local field potential (LFP) in olfactory epithelium (OE), olfactory blub (OB), prefrontal cortex (PFC), and hippocampus (HC) during an olfactory oddball paradigm in urethane anesthetized mice. Odorant presentations evoked neural oscillations across slow and fast frequency bands including delta (1-4 Hz), theta (6-10 Hz), beta (15-30 Hz), low gamma (30-50 Hz), and high gamma (70-100 Hz) in both peripheral and central nervous systems, and the increases were more prominent in the infrequently presented odorant. During 5 s odorant exposures, the oscillatory responses in power were persistent in OE, OB, and PFC, whereas neural oscillations of HC increased only for short time at stimulus onset. These oscillatory responses in power were insignificant in both peripheral and central regions of the ZnSO4-treated anosmia model. These results suggest that olfactory stimulation induce LFP oscillations both in the peripheral and central nervous systems and suggest the possibility of linkage of LFP oscillations in the brain to the oscillations in the peripheral olfactory system.