INTENSITY PROCESSING IN EARS WITH SHIFTED THRESHOLDS

这项研究的总体目标是更好地了解 正常和受损的强度处理的机制 耳朵。 该提案的主要部分探讨了两者之间的关系 响度增长和识别电平小增量的能力， 这称为强度分辨率。 特别感兴趣的是 已知或可能改变强度分辨率的条件和 响度，例如向复杂音调添加音调或检测 宽带噪声（即过冲）开始时出现短音。 这项研究的另一个阶段检查强度之间的关系 患有声学肿瘤的个体的分辨率和响度，以测试 假设适应是造成异常强度的原因 在这些侦听器中进行处理。 患有声学肿瘤的受试者将能够 通常用于建模的激励模式模型的关键测试 正常和听力受损的强度处理。 第三个系列 实验检验认知因素（例如记忆力和记忆力）的作用 上下文）关于响度和强度分辨率。 各种实验 刺激环境（例如，带有线索的前向掩蔽）将提供更多数据 与固定刺激相比，与日常听力条件相关 上下文，但需要研究固定上下文和可变上下文 将认知机制与感觉机制分开。 这项拟议的研究 将为当前模型提供关键的响度和相关测试 强度分辨率并应提供对机制的见解 这些现象的背后。 这些实验的数据也应该 证明在 Hering 假体的设计和安装中很有用，例如 评估人工耳蜗的通道独立性。

The overall goal of this research is to develop a better understanding of the mechanisms that underlie intensity processing in normal and impaired ears. A major portion of this proposal examines the relation between loudness growth and the ability to identify small increments in level, which is known as intensity resolution. Of particular interest are conditions that are known or ar likely to modify intensity resolution and loudness, such as adding tones to a complex tone or the detection of a brief tone during the onset oa a broadband noise (i.e., overshoot). Another phase of this research examines the relation between intensity resolution and loudness in individuals with acoustic tumors to test the hypothesis that adaptation is responsible for the abnormal intensity processing in these listeners. Subjects with acoustic tumors will enable a critical test of excitation-pattern models invoked typically for modeling intensity processing in normal and impaired hearing. A third series of experiments examines the role of cognitive factors (such as memory and context) on loudness and intensity resolution. Experiments with varied stimulus contexts (e.g., forward masking with cues) will provide data more relevant to everyday listening conditions than those from fixed stimulus contexts, but both fixed and variable contexts need to be studied to separate cognitive mechanisms from sensory ones. This proposed research will provide critical tests of current models for relating loudness and intensity resolution and should provide insights into the mechanisms underlying these phenomena. The data from these experiments also should prove useful in the design and fitting of hering prostheses, such as in the evaluation of channel independence in cochlear implants.