Name: face recognition and upside-down faces
Uploaded: 2023-04-30T06:46:13.000Z
Duration: 6 min 13 s
Channel: JoVE
Description: Face recognition is a specialized part of human perception. It often feels effortless, but it actually depends on complex and intensive processing. The brain uses dedicated networks to detect faces and tell them apart.

K12 Standards

new-york-state-science-learning-standards

New York State Science Learning Standards

High School

Life Science

Structure and Function

HS-LS1-2.

The Inverted-face Effect

1.设备和刺激
<ol>
	<li>这个实验需要一台电脑和脚本编写软件的实验。</li>
	<li>此外，这个实验需要一整套相对较大的人脸图像，最好是类似照明条件和无表情。这种图像的多个数据库在自由网上为研究目的。一个好的资源是麻省理工学院的脸数据库: http://web.mit.edu/emeyers/www/face_databases.html#oulu</li>
</ol>
2.设计
<ol>
	<li>组装一套 80 人脸图像。他们分成两半，分成两个组的 40。在意外接触部分的实验中，使用一组和储备要使用作为陪衬的测试部分中的其他组。<ol>
		<li>请注意，两个组应具有相同的相对比例的男性和女性。换句话说，如果有 25 40 的一组中的男性面孔，应该有 25 在其他。</li>
	</ol>
	</li>
	<li>附带的曝光程序<ol>
		<li>实验的第一部分涉及顺便说一句公开一组 40 平面通过封面任务的参与者。</li>
		<li>实验开始与就绪屏幕。按空格键开始曝光。</li>
		<li>一旦按下空格键，每一个 40 面上显示在一个时间为 1 s。后每幅图像，会出现一个屏幕，说:"男/女？"。（掩护任务的参与者是报告是否一张脸是男性或女性）。</li>
		<li>设置程序以前进到第二张脸，参与者按任一后 M 或 F 键，（对应于男性和女性）。图 1在暴露的实验阶段中图式的事件序列化的图解。</li>
		<li>这一阶段是实验的共 40 个审判一个集合中的每个面。</li>
	</ol>
	</li>
</ol>
<img alt="Figure 1" src="/files/ftp_upload/10209/10209fig1.jpg"> 
图 1。旨在展示倒立的面效应附带编码记忆范式方法。实验有两个部分。在第一部分中，被称为附带编码阶段，参与者观察一套 40 的面孔，一个接一个和要求简单报告是否每个面是男性或女性。在第二阶段，参与者给出了一次突击记忆测试。在每个试验中，两副面孔显示肩并肩。每一对之一就是在编码阶段，所示的面孔之一，其他的称为铝箔，是一张新的面孔，从来没有见过的观察员。任务是使用左、 右箭头键来指示每一对中的哪一张脸是前面所看到的。至关重要的是，半脸成对出现颠倒。感兴趣的措施是右侧的报告准确性起相比颠倒的面孔。<a href="https://www.jove.com/files/ftp_upload/10209/10209fig1large.jpg" target="_blank">请点击这里查看此图的大版本。</a>
<ol start="3">
	<li>测试阶段程序<ol>
		<li>实验的测试部分还包括 40 项试验。</li>
		<li>每个试验中，随机选择老面孔之一和以前保留面孔 （同性） 之一。放置一个在屏幕的左边，一个在右边。</li>
		<li>任务是为参与者以指示与左或右箭头键的一对中的人脸以前见过的。</li>
		<li>关键操作是，一半实验，两副面孔介绍了颠倒。</li>
		<li>随机混合颠倒和右上侧审判。</li>
	</ol>
	</li>
</ol>
3.运行实验
<ol>
	<li>在实验开始之前，它是一个好的主意，问参加者，如果她或他有任何已知的视觉障碍或困难，和特别是，如果他们认为他们有任何认识的人的困难。</li>
	<li>座椅的参与者从演示文稿的计算机显示器 60 厘米。</li>
	<li>编码阶段对参与者作如下解释，而没有提及测试阶段来:<ol>
		<li>"这是一个关于面部的认识能力的实验。在每个试验中，您将看到单面一秒钟，紧接着，将要求您确定性别的脸上，你只是看到一个屏幕。男性和女性的 F 键按 M 键。任务可能似乎很容易，因为我们正在进行研究的几个实验，一些包括容易识别的刺激和一些与数位化的改变，更具挑战性的刺激。结果，两者合计，将帮助我们了解用于识别人脸性别的面部特征。是否感觉容易或难到你，请尽你所能。仅有 40 项试验，它将需要少于五分钟才能完成。</li>
	</ol>
	</li>
	<li>开始的程序及站附近作为参与者完成这一阶段的实验。</li>
	<li>当完成后，参与者时，说以下内容:<ol>
		<li>"感谢您完成这项研究的那部分。我只想你现在要做第二个实验，一个也将最后只有五分钟。在每个试验中，您将看到两张脸，在屏幕的左侧和右侧。在每一对面孔之一将是你刚才看到的面孔之一和对方将一张新面孔，你没有出现在判断任务中你只是做了。现在，你的任务是确定的 '老' 的脸，在判断任务中出现的那个。用于在右边脸表明面对在左侧，左的箭头键和右箭头键。在一些试验中，两副面孔显示颠倒。这是不相干的 — — 你的任务是总是尽你所能找出你认为你一次已经看到的脸."</li>
		<li>站在参与者完成记忆测试。</li>
	</ol>
	</li>
</ol>

倒立面孔的发现是很难的过程有很多应用。神经影像学研究，例如，已采取的效果确定大脑区域参与专门的面孔加工的优势。脑部扫描被当观察员直立查看以及倒立面孔。然后比较这两种刺激物的反应。刺激这两组有非常相似的视觉属性总体来看，导致整个视觉系统大量类似活动。不过，一个脑区直立的脸产生更有力的回应，不是倒的暗示倒的面孔未能参与专门的脸处理神经元。这种方式的响应区域称为梭状回或梭状回面孔区 (有时简称 FFA)。这个大脑区域参与了许多其他调查的面孔加工的专业的方面的研究。
另一个应用程序已做称为面容失认症症。这是指极端困难认识到，有时甚至检测的面孔。面容失认症可以出现脑损伤后到梭状回。但它目前已知也出现在人与脑损伤没有已知的原因。一路上那面容失认症评估涉及倒面效应。尤其是，面容失认症患者不显示典型的反演效果。虽然他们有没有更多的麻烦，认识颠倒了面临比他们做起来的右侧，他们有相当多的麻烦，与右侧起来的一般。这种缺乏倒立的面效应表明那面容失认症，因缺乏专门加工系统的种类，似乎知道脸上是通常看的右侧的脸。

倒面效应

资料来源: 实验室的乔纳森 Flombaum — — 约翰 · 霍普金斯大学
感知，在通常的情况是，能够认识和解释复杂的刺激就会感到轻松但实际需求复杂密集处理。这是因为处理是专门和自动化对某些类型的非常重要的刺激。这种现象的最佳范例是面孔加工。人们不尝试检测和识别人脸。似乎只是发生。然而，检测的面孔，并告诉他们彼此是实际上要求苛刻的计算任务。

人类的面部识别能力依赖于专门的计算和专用的大脑网络。一个简单的演示，这是倒面效应。认识到颠倒的面孔是比认识到他们右侧起来，难但也不是如此对于许多其他类型的视觉对象。在以各种方式，证明了倒脸效应。该视频演示附带编码记忆范式为调查面部处理和倒面效应。

结果进行分析，只需计算面孔正确识别与倒置 （倒立） 试验和试验与右边向上 （直立） 面孔的参与的比例。比较性能使用条形图，如图 2所示。最视觉正常的观察员，准确性会高得多，与直立相比倒置的面孔。然而，这是一个困难的任务，和您可能会发现性能低于 0.9 甚至直立的脸。为倒面孔，性能可能甚至方法机会，0.5 什么观察员将分数如果他们只是猜到了每次试验。与倒面孔表现欠佳显示调整专门的计算和用于识别面孔的大脑机制，以充分利用脸都几乎总是经历在竖直方向的事实。
<img alt="Figure 2" src="/files/ftp_upload/10209/10209fig2.jpg"> 
图 2记忆的准确性为倒相比直立的脸。最视觉正常观察员显示相当可观的业绩回顾以前见过的面孔时所示直立，反对倒置。事实上，与倒面孔，性能可以接近机会 (0.5) 在这样的任务。与倒面孔性能差是倒面效应。

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University
In perception, it is often the case that the ability to recognize and interpret ...

我们不会尝试检测和识别人脸，它只是偶然发生的。令人印象深刻的是，为了成功识别，必须在专用的大脑网络中进行复杂且要求苛刻的计算，以将单独的特征集成到一个有凝聚力的面孔中。虽然识别正面朝上的面相对容易，但识别倒置位置的人脸要困难得多，即使其他类型的视觉对象并非如此。这通常被称为倒脸效应，用于旨在研究人脸识别如何在认知和大脑中发生的实验。本视频将演示如何设计和执行，以及如何通过偶然编码记忆范式分析和解释研究倒面效应的实验。在这个实验中，参与者被要求在两个不同的阶段来判断男性和女性的面孔：偶然暴露和测试。在第一个偶然曝光部分，向参与者展示一组 40 张面孔，一次一张，每张面孔 1 秒。显示每张图像后，系统会要求参与者通过按下关联的按键来报告它是男性还是女性。这个过程模仿了我们处理面孔的自然能力——顺便说一句，在不知情的情况下。然后，在第二个测试阶段，参与者将并排显示两张面孔。一个是从偶然暴露部分随机选择的，另一个称为箔片，是性别匹配的，参与者以前从未见过。测试期间的面孔也是随机混合的，其中一半是倒置的，另一半是正面朝上的。要求参与者指出之前见过两者中的哪一个。在这种情况下，因变量是正确识别的直立和倒置方向的人脸数（一种衡量内存准确性的简单度量）。当参与者直立显示时，参与者有望在回忆以前看到的面孔方面表现得更好，而不是倒置。识别倒面时性能不佳称为倒面效果。在开始实验之前，请确认参与者没有任何已知的视觉障碍或识别人的困难。首先，让参与者坐在距离演示计算机 60 厘米的地方。 解释偶然暴露阶段的说明，而不提及即将到来的测试阶段。启动程序并站在附近，让参与者执行实验的第一阶段并在 5 分钟内完成 40 次试验。请注意，他们会看到一张面孔 1 秒，并通过按"M"键（男性）或"F"键（女性）来识别面部的性别。在初始阶段之后，感谢参与者完成这部分研究，并告知他们下一个测试阶段的说明。再次启动程序并站在附近，看着他们完成 40 次试验的第二个记忆阶段。在这部分中，请注意，参与者按向左或向右箭头键来指示之前观察到的人脸。要分析数据，只需计算正确识别的人脸的比例，并按试验类型（直立与倒置）绘制内存准确性结果。请注意，对于大多数视觉正常的参与者，在识别直立面孔而不是倒面时，准确率要高得多，从而展示了倒面效果。倒置的 Almost chance 性能不佳表明，专门的面部处理机制被调整以利用它们几乎总是在直立方向上体验的事实。现在您已经熟悉了处理倒置面所涉及的复杂性，让我们看看可以应用该效果的其他研究方案。神经影像学研究使用倒置面部效应来识别参与专业面部处理的大脑区域。与倒立的面孔相比，直立的面孔在梭形面区域 （FFA） 中产生更强的神经反应，这表明倒立面孔无法参与专门的面孔处理神经元。此外，FFA 的脑损伤可能导致一种称为面容失认症的疾病，即无法识别面孔，包括您自己的面孔。这项任务通常用于诊断面盲症，因为面盲症患者通常与识别倒置面孔一样难以识别正面朝上的面孔。您刚刚观看了 JoVE 对倒置脸效果的介绍。现在，您应该对如何通过实现一系列人脸的编码并通过记忆检索熟悉的人脸来设计和执行此类实验。您还应该知道如何分析和解释结果。感谢观看！

Education

教育

JoVE Science Education

Psychology

心理学

Sensation and Perception

感觉与知觉

face recognition and upside-down faces

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Face Recognition and Upside-Down Faces

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sensation and perception

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Explore how the brain processes faces and why upside-down faces are harder to recognize. Learn the inverted-face effect through incidental memory testing.

Face Recognition and Upside-Down Faces | JoVE K12

Jonathan Flombaum

Overview

Experimental Design

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Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes ...

Ribosomes

Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that ...

Protein and Protein Structures

Proteins: From Genes to Degradation

From DNA to Protein

The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of ...

Protein Folding

Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to ...

An Overview of Gene Expression

Gene expression is the complex process where a cell uses its genetic information to make functional products. This process is regulated at multiple ...

an-introduction-to-caenorhabditis-elegans

An Introduction to Caenorhabditis elegans

Caenorhabditis elegans is a microscopic, soil-dwelling roundworm that has been powerfully used as a model organism since the early 1970&rsquo;s.  It was ...

An Overview of Genetic Analysis

An organism&#8217;s physical traits, or phenotype, are a product of its genotype, which is the combination of alleles (gene variants) inherited from its ...

An Introduction to Cell Death

Necrosis, apoptosis, and autophagic cell death are all manners in which cells can die, and these mechanisms can be induced by different stimuli, such as ...

An Overview of Genetic Engineering

Genetic engineering &#8211; the process of purposefully altering an organism&#8217;s DNA &#8211; has been used to create powerful research tools and model ...

An Introduction to Cell Division

Cell division is the process by which a parent cell divides and gives rise to two or more daughter cells. It is a means of reproduction for single-cell ...

An Overview of Genetics and Disease

Many human diseases are associated with mutations or variations in genetic sequences. Some of these genetic variants are heritable, passed down from ...

an-introduction-to-cellular-and-molecular-neuroscience

An Introduction to Cellular and Molecular Neuroscience

Cellular and molecular neuroscience is one of the newest and fastest growing subdisciplines in neuroscience. By investigating the influences of genes, ...

Annexin V and Propidium Iodide Labeling

Staining with annexin V and propidium iodide (PI) provides researchers with a way to identify different types of cell death&#8212;either necrosis or ...

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An Introduction to Developmental Genetics

Development is the complex process through which a single-celled embryo transforms into a multicellular organism. Developmental processes are guided by ...

Bacterial Transformation: Electroporation

The term &#x201C;transformation&#x201D; refers cellular ingestion of foreign DNA.  In nature, transformation can occur in certain types of bacteria.  In ...

an-introduction-to-molecular-developmental-biology

An Introduction to Molecular Developmental Biology

Molecular signals play a major role in the complex processes occurring during embryonic development. These signals regulate activities such as cell ...

bacterial-transformation-the-heat-shock-method

Bacterial Transformation: The Heat Shock Method

Transformation is the process that occurs when a cell ingests foreign DNA from its surroundings. Transformation can occur in nature in certain types of ...

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An Introduction to Saccharomyces cerevisiae

Saccharomyces cerevisiae (commonly known as baker&rsquo;s yeast) is a single-celled eukaryote that is frequently used in scientific research.  S. ...

Cell Cycle Analysis

Cell cycle refers to the set of events through which a cell grows, replicates its genome, and ultimately divides into two daughter cells through the ...

An Introduction to Transfection

Transfection is the process of inserting genetic material, such as DNA and double stranded RNA, into mammalian cells. The insertion of DNA into a cell ...

Chromatin Immunoprecipitation

Histones are proteins that help organize DNA in eukaryotic nuclei by serving as &#8220;scaffolds&#8221; around which DNA can be wrapped, forming a complex ...

An Overview of Epigenetics

Since the early days of genetics research, scientists have noted certain heritable phenotypic differences that are not due to differences in the ...

community-dna-extraction-from-bacterial-colonies

Community DNA Extraction from Bacterial Colonies

Source: Laboratories of Dr. Ian Pepper and Dr. Charles Gerba - The University of Arizona
Demonstrating Author: Luisa Ikner
Traditional methods of analysis ...

Cytogenetics

Cytogenetics is the field of study devoted to chromosomes, and involves the direct observation of a cell&#8217;s chromosomal number and structure, ...

embryonic-stem-cell-culture-and-differentiation

Embryonic Stem Cell Culture and Differentiation

Culturing embryonic stem (ES) cells requires conditions that maintain these cells in an undifferentiated state to preserve their capacity for self-renewal ...

DNA Gel Electrophoresis

DNA gel electrophoresis is a technique used for the detection and separation of DNA molecules. An electric field is applied to a gel matrix comprised of ...

Enzyme Assays and Kinetics

Enzyme kinetics describes the catalytic effects of enzymes, which are biomolecules that facilitate chemical reactions necessary for living organisms. ...

DNA Ligation Reactions

In molecular biology, ligation refers to the joining of two DNA fragments through the formation of a phosphodiester bond.  An enzyme known as a ligase ...

explant-culture-for-developmental-studies

Explant Culture for Developmental Studies

Explant culture is a technique in which living cells or tissues are removed from an embryo for continued development outside of the organism. This ex vivo ...

DNA Methylation Analysis

Methylation at CpG dinucleotides is a chemical modification of DNA hypothesized to play important roles in regulating gene expression. In particular, the ...

Expression Profiling with Microarrays

Microarrays are important tools for profiling gene expression, and are based on complementary binding between probes that are attached to glass chips and ...

Density Gradient Ultracentrifugation

Density gradient ultracentrifugation is a common technique used to isolate and purify biomolecules and cell structures. This technique exploits the fact ...

F&#246;rster Resonance Energy Transfer (FRET)

F&#246;rster resonance energy transfer (FRET) is a phenomenon used to investigate close-range biochemical interactions. In FRET, a donor photoluminescent ...

detecting-environmental-microorganisms-with-polymerase-chain-reaction

Detecting Environmental Microorganisms with the Polymerase Chain Reaction and Gel Electrophoresis

Source: Laboratories of Dr. Ian Pepper and Dr. Charles Gerba - Arizona University
Demonstrating Author: Bradley Schmitz
Polymerase chain reaction (PCR) is ...

Gel Purification

Gel purification is used to recover DNA fragments after electrophoretic separation. DNA recovery from an agarose gel includes three basic steps: binding, ...

Detecting Reactive Oxygen Species

Reactive oxygen species are chemically active, oxygen-derived molecules capable of oxidizing other molecules. Because of their reactive nature, there are ...

Gene Silencing with Morpholinos

Morpholino-mediated gene silencing is a common technique used to study roles of specific genes during development. Morpholinos inhibit gene expression by ...

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Development and Reproduction of the Laboratory Mouse

Successful breeding of the laboratory mouse (Mus musculus) is critical to the establishment and maintenance of a productive animal colony. Additionally, ...

Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.

HS-LS1-1.

Face Recognition and Upside-Down Faces

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