Classification Images of Data Collected Using the Method of Free Response

描述(申请人提供)：人类听者很容易隔离环境中的众多声源，并处理单一的声流。这一过程需要跨时间和跨频率的信息集成。为了检验时间加工的作用，拟议的心理物理实验采用了很少使用的自由反应方法。在该过程中，掩模呈现几分钟，并且随机时间呈现目标。受试者的任务是每当探测到目标时按下一个按钮。这一过程非常适合于声音分离的研究，因为呈现持续时间很长，反映了“真实世界”的情况。在拟议的实验中，一个主要感兴趣的问题是，自由反应方法的连续性是否增加了受试者的“认知负荷”。第二个主要问题是开发一种方法，确定监听者依靠时间和频率上的哪些“特征”来检测竞争环境中的目标。自由响应方法具有按钮按压随时间展开的优点，允许使用反向相关方法来提取特征，以将按钮按下的时间与其之前的刺激相关联。拟议的实验将评估获得的特征的统计可靠性，这是朝着这一过程的有用应用迈出的第一步。拟议的实验和分析仅限于听力正常的听众。如果该方法被证明是成功的，目前的结果将提供一个基本的数据集，最终可能会与听力受损的听者的结果进行比较(而不是建议)。听力正常的听者能够分离声源的大脑机制(例如，在嘈杂的环境中听到说话者)还没有完全阐明。此外，听力受损的听众隔离声源的能力也受到了损害。拟议的研究将有助于理解声源分离，有可能提供适用于辅助听力装置的基本理解。

DESCRIPTION (provided by applicant): Human listeners are facile at segregating the multitude of sound sources in the environment, and attending to a single sound stream. This process requires the integration of information across time and frequency. In order to examine the role of temporal processing the proposed psychophysical experiments employ the rarely used method of free response. For this procedure a masker is presented for several minutes and a target is presented at random times. The subject's task is to press a button whenever the target is detected. This procedure is well suited to the study of sound segregation because the presentation duration is long, mirroring "real world" situations. One question of primary interest addressed in the proposed experiments is whether the continuous nature of the method of free response increases the "cognitive load" on the subjects. A second primary issue is the development of a method that determines which "features" in time and frequency listeners rely on to detect a target in a competing environment. The method of free response has the advantage that button presses unfold over time, allowing the features to be extracted using reverse correlation methods to relate the time of button presses to the stimulus preceding it. The proposed experiments will evaluate the statistical reliability of the obtained features, a first step towards the useful application of this procedure. The proposed experiments and analyses are restricted to normal-hearing listeners. Should the method prove to be successful, the current results will provide a basic data set against which results from hearing-impaired listeners might ultimately be compared (not proposed). The brain mechanisms by which normal-hearing listeners are able to segregate sound sources (e.g., hearing a talker in a noisy environment) are not fully elucidated. Moreover, the ability of hearing-impaired listeners to segregate sound sources is impaired. The proposed research will contribute to the understanding of sound source segregation, with the potential of providing a basic understanding applicable to assistive hearing devices.