Medical College of Wisconsin, Milwaukee, WI 53226, USA.
Am J Physiol Gastrointest Liver Physiol. 2010 Aug;299(2):G422-9. doi: 10.1152/ajpgi.00161.2010. Epub 2010 May 27.
A better understanding of the central control of the physiology of deglutition is necessary for devising interventions aimed at correcting pathophysiological conditions of swallowing. Positive modulation of the cortical swallowing network can have clinical ramifications in dysphagia due to central nervous system deficits. Our aim was to determine the effect of nutritive sensory input on the cortical swallowing network. In 14 healthy right-handed volunteers, we utilized a paradigm-driven protocol to quantify the number of activated voxels and their signal intensity within the left hemispheric cortical swallowing network by high-resolution functional MRI (fMRI) during five different swallowing conditions. Swallowing conditions included a dry swallow (saliva) and natural water-, lemon-, popcorn-, and chocolate-flavored liquid swallows. Each flavored liquid was presented simultaneously by its image, scent, and taste in random order and tested over three runs. fMRIs were analyzed in a blinded fashion. Average fMRI blood oxygenation level-dependent signal intensity and number of activated voxels during swallowing concurrent with nutritive gustatory, olfactory, and visual stimulations were significantly increased compared with dry/natural water swallows throughout the cortical swallowing network (P < 0.001 and P < 0.05, respectively). Subregion analysis showed the increased activity for flavored liquids in prefrontal, cingulate gyrus, and sensory/motor cortex, but not in precuneus and insula. Concurrent gustatory, olfactory, and visual nutritive stimulation enhances the activity of the cortical swallowing network. This finding may have clinical implications in management of swallowing disorders due to cortical lesions.
为了制定旨在纠正吞咽生理病理状况的干预措施，有必要深入了解吞咽的中枢控制。皮质吞咽网络的正性调节可能会对由于中枢神经系统缺陷引起的吞咽困难产生临床影响。我们的目的是确定营养性感觉输入对皮质吞咽网络的影响。在 14 名健康的右利手志愿者中，我们利用一种范式驱动的方案，通过高分辨率功能磁共振成像（fMRI）在 5 种不同的吞咽条件下量化左半球皮质吞咽网络中激活体素的数量及其信号强度。吞咽条件包括干吞咽（唾液）和自然水、柠檬、爆米花和巧克力味液体吞咽。每种口味的液体都以随机顺序同时通过其图像、气味和味道呈现，并在三个运行中进行测试。fMRI 以盲法进行分析。与干/自然水吞咽相比，在皮质吞咽网络的整个区域中，与营养性味觉、嗅觉和视觉刺激同时吞咽时的平均 fMRI 血氧水平依赖信号强度和激活体素数量显著增加（分别为 P < 0.001 和 P < 0.05）。亚区分析显示，在额前皮质、扣带回和感觉/运动皮质中，与有味液体相关的活动增加，但在楔前叶和岛叶中没有增加。同时进行营养性味觉、嗅觉和视觉刺激可增强皮质吞咽网络的活动。这一发现可能对由于皮质损伤引起的吞咽障碍的管理具有临床意义。
