Teismann Inga K, Steinstraeter Olaf, Stoeckigt Kati, Suntrup Sonja, Wollbrink Andreas, Pantev Christo, Dziewas Rainer
Institute for Biomagnetism and Biosignalanalysis, University of Muenster, Muenster, Germany.
BMC Neurosci. 2007 Aug 2;8:62. doi: 10.1186/1471-2202-8-62.
Sensory input is crucial to the initiation and modulation of swallowing. From a clinical point of view, oropharyngeal sensory deficits have been shown to be an important cause of dysphagia and aspiration in stroke patients. In the present study we therefore investigated effects of functional oropharyngeal disruption on the cortical control of swallowing. We employed whole-head MEG to study cortical activity during self-paced volitional swallowing with and without topical oropharyngeal anesthesia in ten healthy subjects. A simple swallowing screening-test confirmed that anesthesia caused swallowing difficulties with decreased swallowing speed and reduced volume per swallow in all subjects investigated. Data were analyzed by means of synthetic aperture magnetometry (SAM) and the group analysis of the individual SAM data was performed using a permutation test.
The analysis of normal swallowing revealed bilateral activation of the mid-lateral primary sensorimotor cortex. Oropharyngeal anesthesia led to a pronounced decrease of both sensory and motor activation.
Our results suggest that a short-term decrease in oropharyngeal sensory input impedes the cortical control of swallowing. Apart from diminished sensory activity, a reduced activation of the primary motor cortex was found. These findings facilitate our understanding of the pathophysiology of dysphagia.
感觉输入对于吞咽的启动和调节至关重要。从临床角度来看，口咽感觉缺陷已被证明是中风患者吞咽困难和误吸的重要原因。因此，在本研究中，我们调查了功能性口咽破坏对吞咽皮质控制的影响。我们采用全脑MEG研究了10名健康受试者在有或没有局部口咽麻醉的情况下自主吞咽时的皮质活动。一项简单的吞咽筛查测试证实，麻醉导致所有受调查受试者出现吞咽困难，吞咽速度降低，每次吞咽的量减少。数据通过合成孔径磁力计（SAM）进行分析，并使用置换检验对个体SAM数据进行组分析。
正常吞咽分析显示双侧中外侧初级感觉运动皮层激活。口咽麻醉导致感觉和运动激活均显著降低。
我们的结果表明，口咽感觉输入的短期减少会阻碍吞咽的皮质控制。除了感觉活动减弱外，还发现初级运动皮层的激活减少。这些发现有助于我们理解吞咽困难的病理生理学。
