Shirane M, Harrison R V
Department of Otolaryngology, University of Hiroshima, Japan.
Acta Otolaryngol Suppl. 1991;489:32-40. doi: 10.3109/00016489109127705.
It is widely assumed that adequate sensory stimulation is important for the proper post-natal development of the central nervous system, particularly during certain critical or sensitive periods in development. To examine the functional effects of long-term profound deafness on the development of the auditory system, the response properties of neurons in the inferior colliculus (IC) to electrical stimulation of the cochlea were investigated in chinchillas (i) deaf from birth and (ii) deafened as adults. In animals deafened as adults there was a 50% reduction in the number of neurons activated by electrical stimulation of the cochlea, compared with studies in normal controls. In contrast, very few or no responses could be elicited from IC of animals made deaf from birth. The results imply that lack of neural activity in the ascending auditory pathways from an early stage of development results in an inactivation of IC neurons. It is not clear if such inactivity is temporary or permanent.
人们普遍认为，充足的感官刺激对于中枢神经系统出生后的正常发育很重要，尤其是在发育过程中的某些关键或敏感时期。为了研究长期深度耳聋对听觉系统发育的功能影响，研究了龙猫中（i）出生时即耳聋和（ii）成年后致聋的动物下丘（IC）神经元对耳蜗电刺激的反应特性。与正常对照研究相比，成年后致聋的动物中，由耳蜗电刺激激活的神经元数量减少了50%。相比之下，出生时即耳聋的动物的IC几乎没有或根本没有反应。结果表明，从发育早期开始，听觉上行通路中缺乏神经活动会导致IC神经元失活。目前尚不清楚这种无活动状态是暂时的还是永久的。
