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. 刺激材料与设备
<ol>
	<li>本实验需要一台配备基本实验软件的计算机，以及一副耳机和一个相对安静的测试房间（无需隔音处理）。</li>
	<li>实验中的刺激声为频率分别为 1 kHz、2 kHz、3 kHz、4 kHz、5 kHz 和 6 kHz 的纯音。人耳对这一频率范围的声音最为敏感。</li>
	<li>在实验过程中，声音的音量将在 1 至 40 dB 范围内自适应调整，具体方式将在实验设计中说明，以测量受试者在上述六个频率下可感知的最小音量。</li>
</ol>
2. 设计
<ol>
	<li>实验将包含六个区组，每个区组对应六个频率中的一个。这是因为人类对不同频率的听觉阈值各不相同。换句话说，阈值将针对这六个频率分别独立测量。因此，以下设计将生成六个测试程序。</li>
	<li>编写实验程序，使每次试验中呈现指定频率的纯音。
	<ol>
		<li>在每次试验中，受试者的任务是报告其是否听到了所呈现的纯音。使用“Y”键表示“是”的回答，使用“N”键表示“否”的回答。</li>
		<li>实验始终从一个音量非常低的纯音开始——即受试者不应能感知到的声音。将第一个纯音的音量设为 2 dB，持续时间为 200 ms。</li>
		<li>每当受试者做出“是”回答时，下一次试验的音量将降低一个步长；每当受试者做出“否”回答时，音量将增加一个步长。因此，可将实验设计可视化为一个流程图，如图1所示。每次播放的纯音持续时间均为 200 ms。</li>
		<li>实验中包含 30 次试验。</li>
		<li>为保持受试者的视觉注意力，在每次播放纯音后于屏幕上显示“是或否？”字样。</li>
		<li>为此 1 至 6 kHz 范围内的六个频率中的每一个生成一个类似的实验程序，共六个。</li>
		<li>确保程序输出每次试验中所呈现纯音的音量以及受试者给出的回答。</li>
	</ol>
	</li>
</ol>
<img alt="自适应测试流程图；根据“是/否”反应调整试验，音量单位为 dB。" src="/files/ftp_upload/10231/10231fig1.jpg" data-altupdatedat="1761830439000" data-alt="图 1"> 
图 1. 使用听觉阶梯法设计实验的流程图。 第一次试验始终以 2 dB 的不可听音量播放一个音调。由于受试者不应察觉该音调，因此会给出“否”反应，下一次试验的音量将增加 1 dB（至 3 dB）。从第二次试验开始，后续每次试验均遵循相同的规则：若受试者给出“是”反应，则下一次试验的音量减少 1 dB；若给出“否”反应，则下一次试验的音量增加 1 dB。每个频率的实验包含 30 次试验。
3. 实验步骤
<ol>
	<li>请注意，测试者可以轻松地自行测试。</li>
	<li>在参与者戴上耳机之前，按如下方式说明指导语：
	<ol>
		<li>“本实验旨在测量您的听觉阈值，即您能感知到的最微弱或最安静的声音。在每一次试验中，计算机会通过耳机播放一个音调，您只需在听到音调时按下‘Y’键，未听到时按下‘N’键即可。按‘N’键是完全正常的。部分音调会非常微弱，我们并不期望您每次都听到。请如实作答，并尽力而为。实验共包含六个区组，每个区组30次试验。包括中间休息在内，全部六个区组大约需要10分钟。”</li>
	</ol>
	</li>
	<li>当参与者准备就绪后，启动第一个程序，即用于1 kHz音调的程序。</li>
	<li>在参与者完成程序期间，您可离开房间。如有可能，请关闭房门以尽量减少外界噪音干扰。</li>
	<li>第一个实验结束后，询问参与者是否有任何问题。让她休息1-2分钟，期间可取下耳机。</li>
	<li>接着运行用于2 kHz音调的程序。</li>
	<li>然后重复步骤3.4至3.6，直至全部六种音调均完成测试。</li>
</ol>
4. 分析结果
<ol>
	<li>为分析结果，需为六项实验中的每一项单独制作一个表格。</li>
	<li>该表格为实验程序的原始输出结果，应包含试验序号、呈现音调的音量以及受试者提供的反应。图2展示了在音调频率为1 kHz时，前10次试验对应的表格部分内容。</li>
</ol>
<img alt="听力测试数据分析表，1000 Hz 频率下，受试者在不同声音强度下的反应。" src="/files/ftp_upload/10231/10231fig2.jpg" data-altupdatedat="1761830439000" data-alt="图 2"> 
图 2. 听觉阶梯实验所需输出结果的示例表格。 请注意，表中数据来自单个受试者（标记为受试者 #1）和单一频率（1000 Hz）。该表格包含三列：试验序号、该次试验中呈现的音调强度（单位为 dB）以及受试者的反应。
<ol start="3">
	<li>检查以确保您的程序正常运行——即“是”的回答导致音量减小，而“否”的回答导致音量增加。</li>
	<li>现在，绘制一张图表：X轴应为试验次数，Y轴应绘制 体积 该试验所呈现音调的 图3 展示了一个示例。</li>
</ol>
<img alt="音量与试验次数关系图；数据点表示多次试验中声音强度的变化趋势。" src="/files/ftp_upload/10231/10231fig3.jpg" data-altupdatedat="1761830439000" data-alt="图3"> 
图3. 单位受试者对单一音调的示例结果。 该图显示了在30次试验中，每次试验所播放音调的音量（以 dB 为单位）随试验次数的变化情况。主要趋势是：在前几次试验中，受试者无法听到任何音调，因而连续做出“否”反应，从而触发音量逐步上升，直至达到听觉阈值。此时，受试者在“否”和“是”的回答之间来回切换，使研究人员能够确定声音首次可被察觉的临界点。
<ol start="5">
	<li>为每种音调生成类似的图表。</li>
	<li>现在计算实验最后十次试验中每种音调播放音量的平均值。所得数值称为“音量阈值”。</li>
	<li>图4展示了音量阈值随音高变化的示例。</li>
</ol>

听觉阶梯法的主要应用之一是评估听力损伤。除了正常的衰老过程，听力损伤还可能由内耳损伤、脑损伤和疾病引起。通常，听力损伤对某些特定频率的影响比其他频率更为严重。阶梯法可用于判断个体在较窄的频率范围内是否存在特别严重的听力下降，从而提示其听力损伤可能不仅仅是正常衰老所致。图6展示了有听力损伤的60岁个体与无听力损伤的60岁个体的听觉阈值对比。该听力受损个体在4 kHz和5 kHz时出现听力损失，表现为这两个频率下的听觉阈值显著升高。除此之外，该个体的表现与年龄匹配的对照组相似。
<img alt="听力对比图，音量与音调频率；听力受损者与听力正常者的测试结果。" src="/files/ftp_upload/10231/10231fig6.jpg" data-altupdatedat="1761830439000" data-alt="图 6"> 
图 6. 听力受损个体（60 岁）与听力未受损的同龄对照者的音量阈值比较。</str...

确定感知阈值的阶梯法程序

来源：Jonathan Flombaum 实验室——约翰斯·霍普金斯大学
心理物理学是一组感知心理学方法的统称，旨在建立刺激的实际强度与其感知强度之间的关系。心理物理学的一个重要方面是测量感知阈限：光线需要多亮，人才能察觉到它的存在？皮肤上可被感知的最小压力是多少？声音可以低到什么程度仍能被人听到？换句话说，人类能够感知到的最小刺激量是多少？阶梯法是一种高效确定个体感知阈限的技术。

本视频将演示使用阶梯法确定个体听觉阈值的标准方法，即人耳能够感知声音所需的最小音量。

阶梯法的目的是将受试者引导至刚好能够听到音调的音量水平。这一目标通过在最初几次试验中引发一系列“否”反应来实现。一旦出现“是”反应，目标便转为使播放的音量保持在接近首次引发“是”反应的水平。每当受试者给出“是”反应时，音量即相应降低。由此产生的模式表现为：在最初的几次试验中音量稳步上升，随后趋于平稳，并在实验结束前维持在一个较窄的范围内，如图3所示。该狭窄范围的集中趋势即为听阈的测量值。在图3中，听阈明显出现在约6 dB处。计算听阈的一种常用方法是取实验最后10次试验中播放音量的平均值。在图3的情况下，该平均值为6.1 dB。
通过获取六种不同频率声音的实验结果，可以看出感知阈值随频率（通常称为音高）而变化。高音调的声音比低音调的声音更难听到。为了直观地展示这一现象，可将实验中测试的六种声音各自的音量阈值绘制成图，方法与绘制1 kHz声音时相同，如图4所示。图中数据来自一名20岁的受试者。主要趋势是低频声音比高频声音更容易被听到。这是人类听觉系统的一个基本特征，其根源在于人耳内部振动纤毛和听小骨的结构特性。
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来源：Jonathan Flombaum 实验室——约翰斯·霍普金斯大学  
心理物理学是一组感知心理学方法的统称，最初设计用于……

感知心理学的一个分支——心理物理学——致力于研究刺激的实际强度与其感知强度之间的关系。与实际的强度水平一样，感知水平也可以被测量：例如，光线需要多亮才能被观察到，或者声音需要多轻才能被听到。例如，当有人在等待晚餐上桌时，如果他们位于楼梯底部，可能听不到上菜的通知；必须爬上几级台阶才能听到声音，甚至可能需要再往上爬几级才能理解所听到的内容。这种动态调整是阶梯法背后的原理，通过逐步增加或减少刺激强度，可以可靠地确定最小可察觉的刺激强度。本视频演示了如何设计和实施阶梯法实验程序，特别是用于测量听觉阈值——即人耳能够感知到声音所需的最小音量。在本实验中，通过耳机以六种不同频率或音高呈现音调：1–6 kHz，均在人类听觉范围内。由于我们的听阈在不同频率下并不相同，因此采用六个独立的测试区块分别进行检测。在每个区块中，频率以2至40 dB范围内的不同音量短暂呈现200毫秒。第一个音调以最低的2 dB音量播放，此音量水平受试者不应感知到。若确实如此，则在下一次试验中将音量增加1 dB的步长。另一方面，如果能够察觉，则体积减少一个单位。此过程重复进行30次试验，导致体积呈现阶梯状变化。因变量是参与者对是否听到音调的反应。该信息随后与音量强度数据结合，以确定每个频率下的感知音量阈值。实验开始时，在实验室中向参与者打招呼，并让他们在计算机前舒适地坐下。说明任务要求：在每次试验中，计算机会通过耳机播放一个音调，随后，如果听到音调，请按“Y”键，如果未听到，则按“N”键。让受试者戴上耳机，启动与1 kHz音调相关的试验，然后离开房间。完成第一组六个频率的测试后，返回房间并要求参与者取下耳机。回答他们可能提出的任何问题，并给予他们2分钟的休息时间。时间结束后，让参与者重新戴上耳机，开始与下一个音调相关的试验。重复上述步骤，直至所有六个音调均完成测试。 为了分析结果，为每个测试的音调分别生成一个数据表，其中包含试验编号、音量级别和参与者的反应等列。在最初几次试验中，需确认受试者作出了一系列“否”的回应，表明起始时听不到声音，随后应逐步提高音量，直至达到听觉阈值。验证后，绘制每个区组每次试验中播放的音量，如下图所示（1 kHz）。当达到听觉阈值时，注意受试者在“否”和“是”的回答之间来回切换，由此可确定最初可被察觉的声音。这一狭窄范围的集中趋势即为阈值的度量。为计算每个音调下的音量阈值，需对每个区块的最后10次试验取平均值，并将结果绘制成图。可观察到，随着频率的升高，音量阈值 tends to 增加；换言之，低音调比高音调更容易被听到，这是由于耳内纤毛和骨骼的振动特性所致。现在您已经熟悉了这种寻找感知阈值的有效方法，接下来让我们看看它如何被用于研究正常衰老过程中的感觉功能衰退以及暴露于高音量演出环境所造成的影响。阶梯法已被研究人员用于考察人类听阈随年龄增长而发生的变化。总体而言，他们发现音量阈值随着年龄增长而升高。也就是说，对于60岁个体而言，高频声音需要达到20岁个体可听水平的四倍响度才能被听见。研究人员还采用类似方法，将听力正常人群的音量阈值与听力受损者进行比较，以确定缺陷的性质。某些特定频率受到影响，例如 4 和 5 kHz，而其他频率则保持正常，这表明病因是疾病或损伤，而非衰老。此外，该方法还可用于评估各种类型的经历对听觉系统的影响。例如，已有研究采用阈值法来评价在音乐会期间聆听高音量重金属音乐对听力的影响。研究人员在人们参加音乐会前以及结束后半小时进行测试，发现重金属音乐提高了声音的音量阈值。因此，摇滚音乐可能会导致听力下降！您刚刚观看了 JoVE 关于阶梯法的视频。现在，您应该已经很好地掌握了如何设计感知阈值任务、实施实验，以及如何分析和评估实验结果。感谢观看！

Education

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JoVE Science Education

Psychology

心理学

Sensation and Perception

感觉与知觉

查找知觉阈限的楼梯过程

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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just-noticeable differences

Measuring Size Changes with JND

Psychophysics studies how physical changes become neural signals and mental ideas about magnitude. A key idea in this field is the just-noticeable difference, or JND. A JND is the smallest change people can perceive. Size is a clear way to study JND. Small changes in a child’s height may go unnoticed from day to day. After a longer absence, such as a return from sleep-away camp or a visit after many weeks, those same small changes can seem obvious because they have added up. Researchers...

the staircase procedure for finding a perceptual threshold

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...

object substitution masking

Visual Masking with Object Substitution

Visual masking describes cases where one image is presented, but an observer does not perceive it because a second image appears. In vision science, this kind of interference helps researchers study how the brain selects and stores visual information. Object substitution masking is a surprising form of visual masking. It became an important topic in vision research after it was discovered relatively recently, around 1997, by Enns and Di Lollo. The effect has been studied because it shows that...

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

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 ...

propagation-speed-of-electromagnetic-waves

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 ...

an-introduction-to-drosophila-melanogaster

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 ...

an-introduction-to-the-zebrafish-danio-rerio

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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