de Jong Marrigje A, Perez Ronen, Adelman Cahtia, Sohmer Haim
Department of Medical Neurobiology (Physiology), Institute for Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Ann Otol Rhinol Laryngol. 2012 Sep;121(9):625-8. doi: 10.1177/000348941212100911.
Auditory sensation can be elicited by air conduction (AC) and by bone conduction (BC). It is also possible to elicit such responses by applying the standard clinical bone vibrator to the skin over soft tissue sites on the head, neck, or thorax of humans and animals. This mode of auditory stimulation has been called soft tissue conduction (STC). This study was designed to investigate the pathway between soft tissue sites and the ear.
The air in the middle ear was replaced with saline solution in an animal with unique anatomy--the fat sand rat, in which about 70% of a thin-walled inner ear bulges into the middle ear bulla cavity--while we recorded the auditory brain stem responses (ABRs) to AC, BC, and STC stimulation.
This replacement of air with saline solution led to a significant improvement in STC threshold. With AC stimulation, the ABR threshold was elevated and the latency of the first ABR wave was prolonged. Consistent changes were not seen with BC stimulation.
When the air (which has a very low acoustic impedance) that normally surrounds most of the inner ear is replaced with saline solution (which has an acoustic impedance similar to that of soft tissues), the STC threshold is improved. This improvement may be due to improved transmission of acoustic energy from the soft tissues to the inner ear.
听觉感受可通过气导（AC）和骨导（BC）引发。通过将标准临床骨振动器应用于人类和动物头部、颈部或胸部软组织部位的皮肤，也有可能引发此类反应。这种听觉刺激模式被称为软组织传导（STC）。本研究旨在探究软组织部位与耳朵之间的通路。
在具有独特解剖结构的动物——肥沙鼠中，用盐溶液替代中耳内的空气，肥沙鼠约70%的薄壁内耳膨入中耳鼓泡腔，同时我们记录对AC、BC和STC刺激的听觉脑干反应（ABR）。
用盐溶液替代空气导致STC阈值显著改善。在AC刺激下，ABR阈值升高，且第一个ABR波的潜伏期延长。BC刺激未观察到一致的变化。
当通常环绕大部分内耳的空气（其声阻抗非常低）被盐溶液（其声阻抗与软组织相似）替代时，STC阈值得到改善。这种改善可能是由于从软组织到内耳的声能传输得到改善。
