Tannan Vinay, Holden Jameson K, Zhang Zheng, Baranek Grace T, Tommerdahl Mark A
Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
Autism Res. 2008 Aug;1(4):223-30. doi: 10.1002/aur.34.
Adults with autism exhibit inhibitory deficits that are often manifested in behavioral modifications, such as repetitive behaviors, and/or sensory hyper-responsiveness. If such behaviors are the result of a generalized deficiency in inhibitory neurotransmission, then it stands to reason that deficits involving localized cortical-cortical interactions--such as in sensory discrimination tasks--could be detected and quantified. This study exemplifies a newly developed method for quantifying sensory testing metrics. Our novel sensory discrimination tests may provide (a) an effective means for biobehavioral assessment of deficits specific to autism and (b) an efficient and sensitive measure of change following treatment. The sensory discriminative capacity of ten subjects with autism and ten controls was compared both before and after short duration adapting stimuli. Specifically, vibrotactile amplitude discriminative capacity was obtained both in the presence and absence of 1 sec adapting stimuli that were delivered 1 sec prior to the comparison stimuli. Although adaptation had a pronounced effect on the amplitude discriminative capacity of the control subjects, little or no impact was observed on the sensory discriminative capacity of the subjects with autism. This lack of impact of the adapting stimuli on the responses of the subjects with autism was interpreted to be consistent with the reduced GABAergic-mediated inhibition described in previous reports. One significant aspect of this study is that the methods could prove to be a useful and efficient way to detect specific neural deficits and monitor the efficacy of pharmacological or behavioral treatments in autism.
患有自闭症的成年人表现出抑制功能缺陷，这些缺陷通常表现为行为改变，如重复行为和/或感觉过敏。如果这些行为是抑制性神经传递普遍不足的结果，那么可以推断，涉及局部皮质-皮质相互作用的缺陷——比如在感觉辨别任务中——是可以被检测和量化的。本研究例证了一种新开发的量化感觉测试指标的方法。我们新颖的感觉辨别测试可能会提供：（a）一种对自闭症特有的缺陷进行生物行为评估的有效手段，以及（b）一种对治疗后变化进行高效且灵敏的测量方法。在短时间适应性刺激前后，对10名自闭症患者和10名对照者的感觉辨别能力进行了比较。具体而言，在有和没有1秒适应性刺激的情况下均获得了振动触觉幅度辨别能力，该适应性刺激在比较刺激前1秒施加。尽管适应性对对照者的幅度辨别能力有显著影响，但对自闭症患者的感觉辨别能力几乎没有观察到影响。适应性刺激对自闭症患者反应缺乏影响，这被解释为与先前报告中描述的松果体介导的抑制作用降低一致。这项研究的一个重要方面是，这些方法可能被证明是检测自闭症中特定神经缺陷以及监测药物或行为治疗效果的一种有用且高效的方式。
