Name: measuring auditory thresholds with staircase testing
Uploaded: 2023-04-30T06:47:35.000Z
Duration: 6 min 48 s
Channel: JoVE

K12 Standards

new-york-state-science-learning-standards

New York State Science Learning Standards

High School

Physical Science

HS. Waves and Electromagnetic Radiation

HS-PS4-5.

the-staircase-procedure-for-finding-a-perceptual-threshold

The Staircase Procedure for Finding a Perceptual Threshold

1.刺激和设备
<ol>
	<li>本实验将需要具有基本的实验软件，以及一套耳机和一个相对安静的测试房间 （隔音是不必要的） 的计算机。</li>
	<li>在实验中的刺激将与 1 千赫、 2 千赫、 3 千赫、 4 千赫、 5 千赫和 6 千赫频率的音调。人类听觉是最好在此频率范围内。</li>
	<li>在实验过程中，卷的音调会更改自适应范围内的 1 至 40 分贝，将明确在实验设计中，为了测量在每个六个频率可感知体积最小的方面。</li>
</ol>
2.设计
<ol>
	<li>实验将涉及六个大块，一是每六个频率。这是因为人类的阈值是不相同的所有频率。换句话说，阈值将独立测量每个六个频率。以下设计因而会产生六个测试程序。</li>
	<li>实验在每个审判期间呈现某一特定的频率的程序。<ol>
		<li>在每个试验中，参与者的任务会报告是否或不她听到提出了一种语气。使用 'Y' 键来指示是的反应和 n 键以指示 '不' 的反应。</li>
		<li>实验的开头总是将成交量非常低口气-一个参与者应该没有察觉到。程序的第一次的口吻向卷 2 dB 演奏为 200 毫秒。</li>
		<li>每当一个 '是' 的反应产生，在接下来的试用卷将下调一步，和每当产生了 '不' 的响应，它将会增加一步。它是因此可能想象实验设计作为一个流程图，如图 1所示。音调总是将播放一段时间内每 200 毫秒。</li>
		<li>在实验中包括 30 试验。</li>
		<li>为了保持视觉上进行的参与者，词是或否？ ' 后屏幕上显示每个音演奏。</li>
		<li>生成这样，1 和 6 千赫兹之间的六个频率的每个六实验程序。</li>
		<li>请确保该程序输出的口气提出关于每项试验和响应参与者提供卷。</li>
	</ol>
	</li>
</ol>
<img alt="Figure 1" src="/files/ftp_upload/10231/10231fig1.jpg"> 
图 1。使用听觉楼梯过程实验的设计流程图。第一次尝试总是涉及音听不清 2 分贝的音量开到。由于参与者不应该检测那口气，会给一个 '不' 响应，和在下一轮试验量将会增加 1 dB （至 3 分贝）。每个审判 (包括和) 第二次收益与同一指令: 如果 '是' 的反应由参与者提供的在接下来的试用量减少 1 分贝。如果提供了 '不' 的反应，在接下来的试用卷增加 1 dB。实验将包括 30 试验每频率。
3.程序
<ol>
	<li>请注意，可以轻松地测试他或她自己。</li>
	<li>参与者戴上耳机之前，解释指令，如下所示:<ol>
		<li>"这个实验被为了衡量你听觉的阈值，柔软或安静的声音，你能察觉到。在每个试验中，计算机将起通过耳机，语气和所有你需要做的是按 'Y' 键如果你听到声响或 n 键如果你没有。没关系，请按 n 键。一些的调子会变得十分柔软，和我们并不期望你总是听到他们。只是诚实回答，并做到最好。实验内容包括六个街区与 30 项试验。所有的六块应只采取 10 分钟左右，包括在这两者之间的休息时间。</li>
	</ol>
	</li>
	<li>当参与者准备好，推出的第一个程序，一个 1 kHz 色调。</li>
	<li>参加者完成该程序时，你可能会离开房间。关上了门如果可能的话，尽量减少外部噪音。</li>
	<li>完成第一次实验后，要求参与者是否她有任何的问题。让她休息 1-2 分钟，在这段时间删除耳机。</li>
	<li>现在运行的程序 2 kHz 色调。</li>
	<li>然后重复 3.4-3.6，直到所有六种声调已经过测试。</li>
</ol>
4.分析结果
<ol>
	<li>分析的结果，使一个单独的表为每个六个实验。</li>
	<li>表是从实验程序的原始输出。它应包括审判的数目、 卷的口气提出和响应参与者提供。图 2显示的表的部分首先 10 试验用一种口吻的 1 千赫的类似。</li>
</ol>
<img alt="Figure 2" src="/files/ftp_upload/10231/10231fig2.jpg"> 
图 2。示例包括听觉楼梯实验中所需的输出表。请注意，报告的数据是单一学科 （标记为主题 #1） 和单一频率 （1000 赫兹）。表包含三列: 试验次数，提出了关于那审判 （单位 dB) 和参与者的答复的语气的货量。
<ol start="3">
	<li>检查以确保您的程序正常工作-即，'是' 的反应导致减少体积，并没有回应产生而增大体积。</li>
	<li>现在，让图: x 轴应该是，试验次数，和 y 轴应绘制卷的口气提出有关这项试验。图 3显示了一个示例。</li>
</ol>
<img alt="Figure 3" src="/files/ftp_upload/10231/10231fig3.jpg"> 
图 3.样品结果从一个单一的参与者和单音。该图形会卷的演奏，在 dB，作为一个函数为每个 30 试验，试验次数的基调。主要的模式是，参与者不能听到任何音在第一的几个试验中，生产一系列的 '不' 的反应和提示体积增大，直到达到听觉阈值。在这一点上，参与者之间 '不' 来回移动，'是' 响应允许的研究者来标识的地方听起来第一次成为检出。
<ol start="5">
	<li>生成每个音调像这的图。</li>
	<li>现在平均一起卷期间发挥最后十个实验中的每个音。得到的值称为卷门槛。</li>
	<li>图 4 是球场的卷阈值示例作为函数。</li>
</ol>

听觉楼梯过程的主要应用之一是评估听力障碍。超越正常的老化，听力障碍可以引起内耳、 脑损伤和疾病的损害。通常情况下，听力障碍影响特定的频率比其他人更。楼梯法可以用于确定是否有人拥有在窄的工作频率范围内，将建议超过正常老化所引起的听力损伤尤其是听力不好。图 6图听觉阈值为听力受损 60 岁相比未受损伤的 60 岁。受损的个人遭受听力损失在 4 和 5 千赫，在那些频率很高的听觉阈值所示。否则，受损的个人同样执行到年龄匹配控制。
<img alt="Figure 6" src="/files/ftp_upload/10231/10231fig6.jpg"> 
图 6。的体积阈值为听力受损的个人 （60 岁） 相比未受损伤的年龄匹配。听力障碍，往往影响只有频率空间的一部分。此处所示的受损的个人遭受严重损害很高的门槛 — — 在 4 和 5 千赫，不过看起来年龄匹配的对照相比，否则为正常。
<p class="j...

查找知觉阈限的楼梯过程

资料来源: 实验室的乔纳森 Flombaum — — 约翰 · 霍普金斯大学
心理物理学在设计涉及他们感性的强度的实际强度的刺激的知觉心理学是一套的方法的名称。心理物理学的一个重要方面涉及知觉阈限的测量: 多么灿烂光必须要为一个人要能检测到它？施加多少压力，皮肤是检出的吗？如何软可以声音，还能听到吗？把另一种方式，人类能感知的刺激的最小金额是什么？楼梯过程是确定一个人的知觉阈限的一种有效的技术。

这个视频将展示了标准方法应用楼梯过程以确定一个人的听觉阈值，即体积最小音被感知的必要条件。

楼梯程序的目的是使参与者，他们勉强可以听到音卷。这被通过促使一系列的 '不' 第一几个试验中的反应。一旦产生了 '是' 的反应，目标是保持接近 '是' 引起第一次演奏的卷。这是通过降低音量，只要给出一个 '是' 的反应。这将产生量在第一的几个试验中，稳步上升，并然后进入稳定状态，在一个狭窄的范围结束之前剩余的实验中，如图 3 所示，一个模式。这个窄范围的集中趋势是阈值的措施。在图 3 中，很明显在大约 6 分贝达到阈值。一个常见的方法来计算阈值是要计算平均值的卷的演奏在实验的最后 10 审判期间。在图 3 的情况下，平均作品到 6.1 dB。
六个声调的不同频率下得到的实验结果，可以看出感知阈值不同的频率 （通常称为球场）。高音调的声音很难听到比降低音调的。若要以图形方式查看这，情节卷阈值为每个测试在实验中，六种声调就像做为 1 kHz 色调-如图 4 所示。所显示的数据是唯一的参与者，20 岁。主要模式是低频音调更容易听到比高频率的音调。这是一个源自的听觉系统，开始振动的花丝和人类的耳朵里面的骨头的性质与结构的人类听觉的事实。
<p class="jove_content...

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University
Psychophysics is the name for a set of methods in perceptual psychology designed in ...

知觉心理学的一个分支——心理物理学——关注将刺激的实际与其感知强度联系起来。就像实际水平一样，可以测量感知水平：光线必须有多亮才能被观察到，或者声音有多柔和才能被听到。例如，如果某人在楼梯底部，他们可能不会听到晚餐已准备好;他们必须爬上几级台阶才能听到任何声音，甚至可能还要多爬几级台阶才能解释声音。这种动态调整是楼梯手术背后的概念，其中可以通过增加或减少刺激量来可靠地确定最小注意到的强度。该视频演示了如何设计和实施楼梯程序，特别是测量听觉阈值，即感知音调所需的最小音量。在这个实验中，音调通过耳机以六种不同的频率或音高呈现：1？6 kHz？都在人类听觉范围内。鉴于我们的阈值在所有频率上都不相同，因此使用六个块来独立测试每个阈值。在每个块中，频率短暂表示 200 ms，音量范围为 2？40 dB。第一个音调以 2 dB 的最低音量播放，这是参与者不应感知的水平。如果是这种情况，则下一次试验的音量将增加一个步骤，即 1 dB。另一方面，如果很明显，音量会减少 1。此过程重复 30 次试验，导致体积呈阶梯状变化。因变量是参与者？回答 - 无论他们是否听到了语气。然后将此信息与音量强度数据相结合，以确定每个频率的感知音量阈值。要开始实验，请在实验室中向参与者打招呼，并让他们舒适地坐在计算机前。解释任务说明：在每次试验中，计算机将通过耳机播放提示音，然后如果您听到提示音，系统会提示您按"Y"键，如果您没有听到提示音，则提示您按"N"键。允许参与者戴上耳机，开始与 1 kHz 音调相关的试验， 然后离开房间。完成第一个 6 个频率块后，返回房间并要求参与者摘下耳机。回答他们可能有的任何问题，并让他们休息 2 分钟。时间到了，让参与者重新戴上耳机，开始与下一个音调相关的试验。重复这些步骤，直到测试完所有 6 个音调。为了分析结果，为每个测试的音调生成一个单独的数据表，其中一列是试验编号、音量水平和参与者的反应。在最初的几次试验中，验证他们是否以一系列 no？s 响应，这表明音调在开始时是听不见的，这应该促使音量增加，直到达到听觉阈值。验证后，绘制每个模块每次试验时播放的音量，如此处所示，1 kHz 时。当达到听觉阈值时，请注意参与者在"否"和"是"响应之间来回移动，这允许识别最先被检测到的声音。这个狭窄范围的中心趋势是阈值的度量。要计算每个音调的音量阈值，请平均每个 Block 的最后 10 次试验并绘制结果图。观察这如何随着频率的增加而增加;换句话说，低调的音调比较高的音调更容易听到，这是由于耳朵细丝和骨骼的振动特性。现在您已经熟悉了这种寻找感知阈值的有效方法，让我们看看它如何用于检查正常衰老和暴露于响亮表演时的感觉下降。研究人员已使用楼梯程序来检查听力阈值如何随着人类年龄的增长而变化。一般来说，他们发现音量阈值会随着年龄的增长而增加。也就是说，对于 60 岁的人来说，高频声音的音量需要是 20 岁人群能听到的四倍。使用类似的方法，研究人员还比较了听力正常人和有障碍的人的音量阈值，以确定缺陷的性质。特定频率受到影响，例如 4 和 5 kHz，而其他频率则正常，这表明疾病或损伤是原因，而不是衰老。此外，该方法可用于评估各种类型体验对听觉系统的影响。例如，研究使用阈值方法来评估在音乐会期间听到响亮的重金属音乐的影响。当研究人员在参加音乐会前和音乐会后半小时对人们进行测试时，他们发现重金属会增加声音的音量阈值。因此，摇滚音乐会让你听不见！您刚刚观看了 JoVE 关于楼梯手术的视频。现在，您应该对如何设计感知阈值任务和运行实验以及分析和评估结果有很好的了解。感谢观看！

Education

教育

JoVE Science Education

Psychology

心理学

Sensation and Perception

感觉与知觉

measuring auditory thresholds with staircase testing

Psychophysics studies how the physical strength of a stimulus relates to what people actually perceive. It focuses on perceptual thresholds, which are the smallest amounts of stimulation a person can sense. Examples include the brightness needed to see a light, the pressure needed to feel touch, and the softness of a sound that can still be heard.

The staircase procedure is an efficient method for finding a perceptual threshold. Here, the stimulus is adjusted step by step based on a person’s response. The method helps identify when a signal first becomes detectable.

This demonstration uses hearing as the example and measures auditory threshold. Auditory threshold is the minimum volume needed for a tone to be perceived. The standard staircase procedure shown here provides a clear way to test that threshold in perceptual psychology.

Measuring Auditory Thresholds with Staircase Testing

measuring-auditory-thresholds-with-staircase-testing

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sensation and perception

这本文集探讨了各种程序, 研究如何大脑处理我们复杂的感官世界, 解决问题的意识意识和视觉, 触觉, 和听觉感知。

Learn how psychophysics uses the staircase procedure to measure perceptual thresholds, including the minimum volume needed to hear a tone.

Measuring Auditory Thresholds with Staircase Testing | JoVE K12

Life Science

Structure and Function

HS-LS1-2.

Jonathan Flombaum

Overview

Experimental Design

Running the Experiment

Representative Results

Applications

Summary

Travelling Waves

A wave is a disturbance that propagates from its source, repeating itself periodically, and is typically associated with simple harmonic motion. ...

Wave Parameters

The simplest mechanical waves are associated with simple harmonic motion and repeat themselves for several cycles. These simple harmonic waves can be ...

Equations of Wave Motion

Mathematically, the motion of a wave can be studied using a wavefunction. Consider a string oscillating up and down in simple harmonic motion, having a ...

Graphing the Wave Function

Consider the wave equation for a sinusoidal wave moving in the positive x-direction. The wave equation is a function of both position and time. From the ...

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Velocity and Acceleration of a Wave

A wave propagates through a medium with a constant speed, known as a wave velocity. It is different from the speed of the particles of the medium, which ...

Speed of a Transverse Wave

The speed of a wave depends on the characteristics of the medium. For example, in the case of a guitar, the strings vibrate to produce the sound. The ...

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Problem-Solving: Tuning of a Guitar String

In the case of stringed instruments like the guitar, the elastic property that determines the speed of the sound produced is its linear mass density or ...

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Kinetic and Potential Energy of a Wave

All forms of waves carry energy; this is directly visualized in nature. For instance, the waves of earthquakes are so intense that they can shake huge ...

Energy and Power of a Wave

The total energy associated with a wavelength is the sum of the potential energy and the kinetic energy. The average rate of energy transfer associated ...

Interference and Superposition of Waves

When two waves of the same nature occur in the same region simultaneously, they result in interference. Interference of waves implies that the net effect ...

Reflection of Waves

When a wave travels from one medium to another, it gets reflected at the boundary of the second medium. A common example of this is when a person yells at ...

Propagation of Waves

When a wave propagates from one medium to another, part of it may get reflected in the first medium, and part of it may get transmitted to the second ...

Standing Waves

Sometimes waves do not seem to move; rather, they just vibrate in place. Unmoving waves can be seen on the surface of a glass of milk kept in a ...

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Modes of Standing Waves - I

A close look at earthquakes provides evidence for the conditions appropriate for resonance, standing waves, and constructive and destructive interference. ...

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Modes of Standing Waves: II

The starting point for expressing the modes of standing waves is understanding the boundary conditions that the waves must follow. The boundary conditions ...

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Sound Waves

Sound waves can be thought of as fluctuations in the pressure of a medium through which they propagate. Since the pressure also makes the medium&#39;s ...

Sound as Pressure Waves

Sound waves, which are longitudinal waves, can be modeled as the displacement amplitude varying as a function of the spatial and temporal coordinates. As ...

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Perception of Sound Waves

The human ear is not equally sensitive to all frequencies in the audible range. It may perceive sound waves with the same pressure but different ...

Speed of Sound in Solids and Liquids

Most solids and liquids are incompressible&#8212;their densities remain constant throughout. In the presence of an external force, the molecules tend to ...

Speed of Sound in Gases

The speed of sound in a gaseous medium depends on various factors. Since gases constitute molecules that are free to move, they are highly compressible. ...

Shock Waves

While deriving the Doppler formula for the observed frequency of a sound wave, it is assumed that the speed of sound in the medium is greater than the ...

Echo

The human ear cannot distinguish between two sources of sound if they happen to reach within a specific time interval, typically 0.1 seconds apart. More ...

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Use mathematical representations to support a claim regarding relationships among the period, frequency, wavelength, and speed of waves traveling and transferring energy (amplitude, frequency) in various media.

HS-PS4-1.

Using GIS to Investigate Urban Forestry

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University
Urban forests broadly include urban parks, street trees, landscaped ...

Evaluate questions about the advantages of using a digital transmission and storage of information.

HS-PS4-2.

concept-of-resonance-and-its-characteristics

Concept of Resonance and its Characteristics

If a driven oscillator needs to resonate at a specific frequency, then very light damping is required. An example of light damping includes playing piano ...

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Sound Waves: Resonance

Resonance is produced depending on the boundary conditions imposed on a wave. Resonance can be produced in a string under tension with symmetrical ...

Sound Waves: Interference

Sound waves can be modeled either as longitudinal waves, wherein the molecules of the medium oscillate around an equilibrium position, or as pressure ...

Interference: Path Lengths

Consider two sources of sound, that may or may not be in phase, emitting waves at a single frequency, and consider the frequencies to be the same.
Two ...

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The Wave Nature of Light

The nature of light has been a subject of inquiry since antiquity. In the seventeenth century, Isaac Newton performed experiments with lenses and prisms ...

The Electromagnetic Spectrum

The electromagnetic spectrum consists of all the types of electromagnetic radiation arranged according to their frequency and wavelength. Each of the ...

The Quantum-Mechanical Model of an Atom

Shortly after de Broglie published his ideas that the electron in a hydrogen atom could be better thought of as being a circular standing wave instead of ...

Quantum Numbers

It is said that the energy of an electron in an atom is quantized; that is, it can be equal only to certain specific values and can jump from one energy ...

Interference and Diffraction

Source: Yong P. Chen, PhD, Department of Physics &#38; Astronomy, College of Science, Purdue University, West Lafayette, IN
Interference and diffraction ...

Photoelectric Effect

Source: Yong P. Chen, PhD, Department of Physics &#38;&#38; Astronomy, College of Science, Purdue University, West Lafayette, IN
Photoelectric effect ...

Reflection and Refraction

Source: Derek Wilson,&#160;Asantha Cooray, PhD, Department of Physics &#38; Astronomy, School of Physical Sciences, University of California, Irvine, CA
...

Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be described either by a wave model or a particle model (quantum theory), and that for some situations one model is more useful than the other.

HS-PS4-3.

Electric Charge in a Magnetic Field

Source: Andrew Duffy, PhD, Department of Physics, Boston University, Boston, MA
This experiment duplicates J.J. Thomson's famous experiment at the end of ...

Electromagnetic Fields

Electric fields generated by static charges, often referred to as electrostatic fields, are characteristically different from electric fields created by ...

Electromagnetic Waves

James Clerk Maxwell formulated a single theory combining all the electric and magnetic effects scientists knew during that time, calling the phenomena his ...

Electromagnetic waves are categorized according to their wavelengths and frequencies, giving the electromagnetic spectrum. These waves are classified as ...

Plane Electromagnetic Waves I

The existence of combined electric and magnetic fields that propagate through space as electromagnetic (EM) waves is the most significant prediction of ...

Plane Electromagnetic Waves II

Consider a plane wavefront traveling in position x-direction with a constant speed. This wavefront can be utilized to obtain the relationship between ...

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Propagation Speed of Electromagnetic Waves

Electromagnetic waves are consistent with Ampere&#39;s law. Assuming there is no conduction current Ampere&#39;s law is given as:


Consider a plane ...

Electromagnetic Waves in Matter

Electromagnetic waves can travel in the vacuum as well as in matter. For example light, which is an electromagnetic wave, can travel through air, water, ...

Energy Carried By Electromagnetic Waves

Anyone who has used a microwave oven knows there is energy in electromagnetic waves. Sometimes, this energy is obvious, such as in the summer sun&#39;s ...

Intensity Of Electromagnetic Waves

The energy transport per unit area per unit time, or the Poynting vector, gives the energy flux of an electromagnetic wave at any specific time. For a ...

Momentum And Radiation Pressure

An object absorbing an electromagnetic wave would experience a force in the direction of propagation of the wave. This force occurs because ...

Cardiac Magnetic Resonance Imaging

Source: Frederick W. Damen and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
In this video, high ...

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An Introduction to Drosophila melanogaster

Drosophila melanogaster, also known as the fruit fly, is a powerful model organism widely used in biological research that has made significant ...

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An Introduction to the Zebrafish: Danio rerio

Zebrafish (Danio rerio) are small freshwater fish that are used as model organisms for biomedical research. The many strengths of these fish include their ...

Evaluate the validity and reliability of claims in published materials of the effects that different frequencies of electromagnetic radiation have when absorbed by matter.

HS-PS4-4.

Measuring Auditory Thresholds with Staircase Testing

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