A psychological study of vibrotactile temporal summation

描述(由申请者提供)：该项目的长期目标是扩展我们对触觉感觉系统的时间和空间特性的知识。在人类手部无毛皮肤的四种心理物理通道(P、NP I、NP II和NP III)中，仅有P通道及其环状小体受体和PC周围神经纤维具有时空总和功能。在时间总和中，感觉阈值作为刺激持续时间的函数而下降，而在空间总和中，感觉阈值随着刺激大小的增加而下降。我们的目标是确定P通道中负责求和的潜在过程的性质，并试图从这一知识中确定为什么在NP通道中没有求和。已知的在感觉系统中进行时间和空间求和的两个过程是神经整合和概率求和，其中神经活动作为刺激的持续时间或大小的函数而增加，而概率求和由于敏感度的变化，超过神经阈值的概率随着刺激的持续时间或大小的增加而增加。我们的目标是确定这些过程在触觉感觉系统的时间总和和空间总和中的作用。我们的目标也是确定四个通道中的每一个对感知不同纹理的复杂时空显示的贡献，并在这样做的过程中测试这样的假设，即对特定感知属性的感知，例如粗糙或清晰度，来自多个通道的组合活动，而不是来自单个通道的独占活动。

DESCRIPTION (provided by applicant): The broad long-term goal of the project is to extend our knowledge of the temporal and spatial properties of the tactile sensory system. Of the four psychophysical channels of the glabrous skin of the hands of humans (P, NP I, NP II, and NP III) only the P channel with its Pacinian corpuscles as receptors and PC peripheral nerve fibers have been found to be capable of temporal and spatial summation. In temporal summation, sensory thresholds decline as a function of the duration of the stimulus, and in spatial summation the threshold declines as the size of the stimulus increases. It is our objective to determine the nature of the underlying processes responsible for summation in the P channel and from this knowledge to attempt to determine why summation is absent in the NP channels. The two processes known to operate in temporal and spatial summation in sensory systems are neural integration in which neural activity increases as a function of either the duration or the size of a stimulus and probability summation in which, because of variability in sensitivity the probability of exceeding the neural threshold increases as either the duration or the size of the stimulus increases. It is our objective to determine the role of these processes in temporal summation and spatial summation in the tactile sensory system. It is also our objective to determine the contributions of each of the four channels to the perception of complex spatio- temporal displays of varied texture, and in so doing to test the hypothesis that the perception of a particular perceptual attribute, such as roughness or clarity, arises from the combined activity of multiple channels rather than from the exclusive activity of a single channel.