This research was supported by an NSF Graduate Research Fellowship to Danielle R. Perszyk and a NIH grant to Sandra R. Waxman (R01HD083310).

The following procedures were approved by the Northwestern University Institutional Review Board and informed consent was obtained from the caregivers of all infants. We recruited infants being raised in environments with more than 50% exposure to English11,17. Infants in all experiments first listened to a soundtrack in which we manipulated their exposure to either lemur vocalizations or backward speech; they then participated in an object categorization task. What varied across infants was (a) the kind of signal they heard in the exposure manipulation and the categorization task (either lemur vocalizations or backward speech) and (b) the extent of the exposure phase (either brief exposure in the lab or prolonged exposure at home). For all infants, the categorization task took place in the lab.
1. Materials
<ol>
	<li>How to create the exposure manipulations
	<ol>
		<li>Select 8 distinct samples of lemur vocalizations and 8 distinct samples of backward speech, each 2 to 4 s in duration. Together, the 8 samples should yield 30 s of each acoustic signal. Ensure that the lemur and backward speech segments are matched as closely as possible for duration (e.g., ~3 s in duration) and for mean frequency (e.g., ~300 Hz).
		<ol>
			<li>To obtain lemur vocalizations, search a database of animal vocalizations or contact a researcher who collects animal vocalizations.</li>
			<li>To create backward speech segments, use a laptop and a software program (e.g., Audacity) to (1) record a research assistant speaking ~3 s sentences in infant-directed speech and (2) temporally reverse (in Audacity: Effect &#62; Reverse) each speech segment.</li>
		</ol>
		</li>
		<li>Choose a piece of classical instrumental music that is longer than 4 min. Here, we used the first 4 min of Beethoven&#39;s String Quartet in C Minor, Op 18 No. 4: III. Menuetto.</li>
		<li>Use an audio editing software program (e.g., Audacity) to import the music (in Audacity: File &#62; Import) and select a portion of the piece that is approximately 4 min in duration (highlight and delete the remainder of the piece).
		<ol>
			<li>Create 2 distinct soundtracks by inserting (i.e., copying and pasting) the 8 selected segments of each type (lemur vocalizations or backward speech) into the musical soundtrack.</li>
			<li>To create the &#34;Lemur&#34; soundtrack, open the 8 lemur vocalization sound files in the same software program (e.g., Audacity) and insert them into the file with the music.
			<ol>
				<li>To do so, highlight an entire lemur vocalization, navigate to Edit &#62; Copy, place the cursor in the music file, and navigate to Edit &#62; Paste. Insert the vocalizations at irregular intervals throughout the soundtrack. Do not place them at musical phrase boundaries. Do this twice for each lemur vocalization, inserting them in a pseudorandomized order to ensure that no 2 identical vocalizations occur in a row. Together, this yields a 5 min loop (4 min of music, interspersed with 1 min of lemur vocalizations).</li>
				<li>Repeat this 5 min soundtrack so that the entire soundtrack lasts approximately 10 min. To do so, highlight the entire 5 min section, navigate to Edit &#62; Copy, place the cursor at the end of the 5-min section, and navigate to Edit &#62; Paste.</li>
			</ol>
			</li>
			<li>To create the 10 min &#34;Backward Speech&#34; soundtrack, replace each lemur vocalization in the Lemur soundtrack with a selected segment of backward speech, using the same pseudorandomized order.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>How to create the categorization task
	<ol>
		<li>Visual materials: Create 2 sets of line drawings by hand. In each set, include 9 members of the same object category (here, use 9 distinct drawings of dinosaurs and 9 distinct drawings of fish). Use a different bright color for each drawing within a given category. Scan these drawings onto a computer and save them as image files. Note that the drawings should be unfamiliar objects to infants at the ages tested.</li>
		<li>Acoustic materials: Select one lemur vocalization and one backward speech segment that were not included in either of the exposure manipulations (1.1.3). Match the lemur and backward speech segments as closely as possible for duration (e.g., ~3 s in duration) and for mean frequency (e.g., ~300 Hz).</li>
		<li>Program a task in MATLAB that includes a familiarization phase and a test phase; this task will be projected onto a 5 ft by 5 ft screen in front of the infant.
		<ol>
			<li>Program the familiarization phase such that 8 of the visual exemplars from a single category (e.g., 8 dinosaurs, each a different color) appear sequentially. Each exemplar should appear for 20 s, on either the right or left side of a screen, in alternating fashion. Create 2 distinct versions, pairing each familiarization exemplar with one of the acoustic stimuli below (&#34;Lemur&#34; and &#34;Backward Speech&#34; conditions, respectively). In both conditions, the acoustic stimulus should occur twice on each familiarization trial; once when the visual exemplar appears, and once again 10 s later.
			<ol>
				<li>In the Lemur condition, program each familiarization exemplar to appear simultaneously with a lemur vocalization.</li>
				<li>In the Backward Speech condition, program each familiarization exemplar to appear simultaneously with a backward speech segment.</li>
			</ol>
			</li>
			<li>During the test phase, present the 9th exemplar from the familiar category (e.g., another dinosaur) and an exemplar from the other category (e.g., a fish). These two images should be identical in color and presented simultaneously (one presented on the right and the other on the left side of the screen) in silence for 20 s.</li>
		</ol>
		</li>
		<li>In programming the categorization task, counterbalance (1) which category will be presented during the familiarization phase, (2) the side on which the first familiarization image will appear, and (3) the side on which the novel and familiar test images will appear.</li>
	</ol>
	</li>
</ol>
2. General Procedures
<ol>
	<li>Exposure phase
	<ol>
		<li>Place the infant close to the caregiver or on their lap in a quiet area. Place a laptop or tablet within the infant&#39;s viewing range (from 1 to 4 ft from the infant).</li>
		<li>Use the laptop or tablet to present either the Lemur or the Backward Speech soundtrack.</li>
	</ol>
	</li>
	<li>Categorization task
	<ol>
		<li>In a semi-darkened test room in the lab, seat the caregiver on a chair 4 ft from a 5 ft by 5 ft screen. Connect the laptop with the categorization task programmed in MATLAB to (1) the screen that will display the categorization task and (2) a projector that will project the task onto the screen.</li>
		<li>Seat the infant on the caregiver&#39;s lap, facing forward.</li>
		<li>Instruct the caregiver to avoid influencing the infant&#39;s behavior in any way. More specifically, instruct them to remain quiet and still throughout the duration of the task and to keep their infant centered, using their midline as a guide. Provide caregivers with a pair of blacked-out glasses to ensure that they cannot see the visual materials.</li>
		<li>Turn on the projector.</li>
		<li>Turn on recording equipment to capture the infants&#39; behavior throughout the task.</li>
		<li>Begin the categorization task by pressing &#34;Run&#34; in MATLAB: Present the Lemur condition if the infant was exposed to the Lemur soundtrack and the Backward Speech condition if the infant was exposed to the Backward Speech soundtrack.</li>
	</ol>
	</li>
	<li>Coding (categorization task only)
	<ol>
		<li>Code the onset and offset of each infant&#39;s left and right looks during both the familiarization and test phases.</li>
		<li>Exclude infants who (1) look at fewer than 6 of the familiarization exemplars; (2) look during less than 40% of the familiarization phase. Also exclude infants if there is parental interference, experimental error or technical failure, or if their performance at test is greater than 2 SD from the mean.</li>
	</ol>
	</li>
	<li>Analyses
	<ol>
		<li>For the familiarization phase, calculate the total the amount of time each infant looked at the familiarization objects.</li>
		<li>For the test phase, calculate a preference score for each infant: (total looking time to novel test image)/(total looking time to both test images).</li>
	</ol>
	</li>
</ol>
3. Experiment 1: Brief Exposure to Lemur Vocalizations
<ol>
	<li>Participants
	<ol>
		<li>Recruit 14 infants at 6 to 7 months of age.</li>
	</ol>
	</li>
	<li>Procedure
	<ol>
		<li>Invite the caregiver and infant into a quiet, comfortable room. In our lab, this room is adjacent to the testing room.</li>
		<li>Exposure manipulation: Play the Lemur soundtrack once, with the music visualizer (e.g., iTunes) present on the screen.</li>
		<li>Categorization task: When the soundtrack finishes, guide the caregiver and infant into the testing room. Begin the categorization task (Lemur condition).</li>
	</ol>
	</li>
</ol>
4. Experiment 2: Brief Exposure to Backward Speech
<ol>
	<li>Participants
	<ol>
		<li>Identical to Experiment 1.</li>
	</ol>
	</li>
	<li>Procedure
	<ol>
		<li>Invite the caregiver and infant into a quiet, comfortable room.</li>
		<li>Exposure manipulation: Play the Backward Speech soundtrack once, with the music visualizer present on the screen.</li>
		<li>Categorization task: When the soundtrack finishes, guide the caregiver and infant into the testing room. Begin the categorization task (Backward Speech condition).</li>
	</ol>
	</li>
</ol>
5. Experiment 3: Prolonged Exposure to Lemur Vocalizations
<ol>
	<li>Participants
	<ol>
		<li>Recruit 14 infants at 4.5 months of age.</li>
	</ol>
	</li>
	<li>Procedure
	<ol>
		<li>By phone, invite the caregiver to participate in a 6 week long study. Explain that the study requires them to expose their infant, at home, to a 10 min soundtrack that contains 8 min of music and 2 min of lemur vocalizations (i.e., Lemur soundtrack). Explain that the study lasts for 6 weeks, beginning when the infant is 4.5 months and ending when the infant is 6 months of age.</li>
		<li>Provide caregivers with this precise tapering schedule7,8,18
		<ol>
			<li>Week 1: Play the soundtrack to infant once a day, every day.</li>
			<li>Week 2: Play the soundtrack to infant once every other day.</li>
			<li>Week 3: Play the soundtrack to infant 3 times during the week.</li>
			<li>Weeks 4-6: Play the soundtrack to infant 2 times per week.</li>
		</ol>
		</li>
		<li>To ensure the fidelity of the exposure manipulation throughout the 6 week exposure manipulation, share with caregivers an online interactive document that (a) outlines their role at every step throughout the 6 week period and (b) asks them to record each date and time at which they played the soundtrack to their infant.</li>
		<li>Send weekly reminders by phone or email to keep caregivers engaged and on track.</li>
		<li>During Week 5, schedule a lab visit for the following week (Week 6). Instruct caregivers that infants should listen to the soundtrack 2 to 4 days before their scheduled lab visit; infants should not listen to the soundtrack either on the day of or the day preceding their visit. 
		NOTE: At the lab visit, there is no exposure manipulation: Infants participate only in the categorization task from Experiment 1 (Lemur condition).</li>
	</ol>
	</li>
</ol>

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The authors have nothing to disclose.

Here we outline a procedure for examining the role of experience in linking sounds and core cognitive processes early in infancy. Our combined experiments document the first evidence that experience plays a central role in guiding infants to specify which signals, from a broad initial set of possibilities, they will harness to core conceptual processes that ultimately provide the foundations of meaning. They also reveal an intricate interface between nature and nurture: Although experience plays little role, if any, in d...

Human infants are born ready to acquire language, a cultural and cognitive tool that defines us as a species and fundamentally shapes our development. Central to our capacity for learning language are two unique features of human development: Our altriciality and our powerful learning strategies. Together, these features unlock a remarkable degree of early plasticity that enables infants to be highly attuned to input from their environments. For example, although infants come into the world with a set of perceptual preferences and discriminatory capacities sufficiently broad to include the faces and voices of human and nonhuman primates, within months they narrow these preferences to exclusively human signals1,2,3. This process of perceptual narrowing is adaptive on two counts: It increases the signal-to-noise ratio of relevant communicative signals &#8212; those that will guide infants to efficiently and accurately navigate their complex social world &#8212; and it paves the way for integrating information across perceptual modalities (e.g., integrating faces and voices)4 &#8212; an essential element for the multimodal nature of human language. Moreover, because of infants&#39; early plasticity, perceptual narrowing can be prevented or reversed with exposure to nonnative signals (e.g., nonnative language, nonhuman faces, foreign musical rhythms)5,6,8. This illustrates that perceptual narrowing is experience-driven.
Yet to master their native language, infants must do more than tune in to the faces and voices of its speakers. The power of human language is inextricably linked to cognition9. Incredibly, even in their first year of life, infants have begun to link language and cognition: Simply listening to human language promotes infants&#39; ability to form object categories, a building block for their cognition10,11,12.
This is not to say that infants can only form object categories if they are listening to language. On the contrary, decades of research reveal that infants in their first months of life can form at least some object categories in the absence of any sounds13. But not all object categories are equally easy for infants to form. The slightly more difficult categories provide a powerful opportunity to uncover what effect, if any, language may have on infant categorization. To do so, researchers identify object categories that are more difficult for infants to discern in the absence of other supporting information (like language) and then ask whether language (and other sounds) offer infants any advantage in categorization.
Using this logic, an early link between language and object categorization was documented in a novelty preference paradigm designed to accommodate very young infants (Figure 1b)11. This paradigm has two phases. During the familiarization phase, all infants view images of a series of distinct objects (e.g., dinosaurs) presented sequentially in conjunction with a sound. During the test phase, all infants view two new images in silence: One is a new member of the now-familiar category (e.g., another dinosaur) and the other is a member of a novel category (e.g., a fish). Infants&#39; looking time at test serves as an index of categorization. If infants form the category during familiarization, then at test they should distinguish the novel from the familiar image. If infants fail to do so, then at test they should perform at chance14,15,16.
The results were striking. At 3, 4, and 6 months, infants listening to language during familiarization &#8212; but not tone sequences &#8212; successfully formed object categories11,17. Surprisingly, language is not the only sound that exerts this cognitive advantage: At 3 and 4 months, listening to vocalizations of nonhuman primates (Madagascar, blue-eyed lemur: Eulemur macaco flavifrons) confers the same cognitive advantage as human vocalizations17. By 6 months of age, however, infants have tuned this initially broad link specifically to human vocalizations; lemur vocalizations no longer exert an advantageous effect on infant categorization17.
But what mechanism underlies infants&#39; increasing precision in linking language and cognition? Here, we consider the contribution of infants&#39; experience. Does infants&#39; rich experience with human language (and their dearth of experience listening to lemur vocalizations) play a role as they narrow the link between initially privileged signals (e.g., human and nonhuman primate vocalizations) and the core cognitive process of object categorization? Certainly, we cannot test this by manipulating infants&#39; exposure to language. But we can manipulate their exposure to lemur vocalizations. We focus on infants at 6 and 7 months of age &#8212; infants who, in the absence of exposure, no longer link lemur vocalizations and object categorization17. In Experiment 1, we ask whether brief exposure to lemur vocalizations permits them to preserve the link between this signal and object categorization. In Experiment 2, we ask whether brief exposure to backward speech &#8212; a signal that consistently fails to support object categorization at any age17 &#8212; also promotes object categorization. In Experiment 3, we put the question of exposure to a more stringent test, examining whether more prolonged exposure to lemur vocalizations permits them to preserve their initially-broad link.

<table><tbody><tr><td>Laptop 1</td><td></td><td></td><td>Use for presenting exposure soundtrack; preferably using iTunes Visualizer</td></tr><tr><td>Laptop 2</td><td></td><td></td><td>Use for programming and presenting categorization task</td></tr><tr><td>Laptop 3 (optional)</td><td></td><td></td><td>Use for coding infant looking behavior (can also use one of the above laptops)</td></tr><tr><td>Coding software</td><td>SuperCoder</td><td></td><td>Use for coding infant looking behavior</td></tr><tr><td>Video recorder</td><td></td><td></td><td>Use for recording infants&#039; face (looking behavior during categorization task)</td></tr><tr><td>Mixer</td><td></td><td></td><td>Use for integrating information from the video recorder (infant looking behavior) and the visual stimuli (categorization task)&amp;nbsp;</td></tr><tr><td>DVD player</td><td></td><td></td><td>Use for recording the input from the video recorder (infant looking behavior)</td></tr><tr><td>Television</td><td></td><td></td><td>Use for viewing input from mixer (screen-in-screen; categorization task in corner of screen showing infant looking behavior)&amp;nbsp;</td></tr><tr><td>Projector</td><td></td><td></td><td>Use for projecting visual stimuli of categorization task on screen</td></tr><tr><td>Speakers</td><td></td><td></td><td>Use for presenting auditory stimuli during categorization task</td></tr><tr><td>Blacked-out sunglasses</td><td></td><td></td><td>Use for blocking caretaker&#039;s vision during categorization task</td></tr><tr><td>Statistical analysis software</td><td>R</td><td></td><td>Use for analyzing infant looking behavior</td></tr></tbody></table>

experience is instrumental in tuning a link between language and cognition: evidence from 6-  to 7- month-old infants' object categorization

At birth, infants not only prefer listening to human vocalizations, but also have begun to link these vocalizations to cognition: For infants as young as three months of age, listening to human language supports object categorization, a core cognitive capacity. This precocious link is initially broad: At 3 and 4 months, vocalizations of both humans and nonhuman primates support categorization. But by 6 months, infants have narrowed the link: Only human vocalizations support object categorization. Here we ask what guides infants as they tune their initially broad link to a more precise one, engaged only by the vocalizations of our species. Across three studies, we use a novel exposure paradigm to examine the effects of experience. We document that merely exposing infants to nonhuman primate vocalizations enables infants to preserve the early-established link between this signal and categorization. In contrast, exposing infants to backward speech &#8212; a signal that fails to support categorization at any age &#8212; offers no such advantage. Our findings reveal the power of early experience as infants specify which signals, from an initially broad set, they will continue to link to cognition.

Using the procedures outlined above (Figure 1), we ran three experiments to test the effects of exposure as infants refine the links between certain sounds and cognition.
Results of Experiment 1 revealed that brief exposure to lemur vocalizations had a striking effect. Seven month-olds exposed to lemur vocalizations reliably preferred the novel test image, M = 0.57, SD = 0.09; t(13) = ...

Watch this Scientific Journal Video about Experience is Instrumental in Tuning a Link Between Language and Cognition: Evidence from 6-  to 7- Month-Old Infants' Object Categorization at JoVE.com

Experience is Instrumental in Tuning a Link Between Language and Cognition: Evidence from 6-  to 7- Month-Old Infants' Object Categorization

At 3-4 months, listening to human and nonhuman primate vocalizations boosts infants&#39; cognition; by 6 months, only human vocalizations exert this cognitive advantage. We describe an exposure manipulation that reveals the powerful shaping role of experience as infants specify which sounds to link to cognition and which to tune out.

At birth, infants not only prefer listening to human vocalizations, but also have begun to link these vocalizations to cognition: For infants as young as ...

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6.6K 조회수.  Northwestern University. At 3-4 months, listening to human and nonhuman primate vocalizations boosts infants' cognition; by 6 months, only human vocalizations exert this cognitive advantage. We describe an exposure manipulation that reveals the powerful shaping role of experience as infants specify which sounds to link to cognition and which to tune out.

비디오: Experience is Instrumental in Tuning a Link Between Language and Cognition: Evidence from 6-  to 7- Month-Old Infants' Object Categorization

Creating Objects and Object Categories for Studying Perception and Perceptual Learning

In order to quantitatively study object perception, be it perception by biological systems or by machines, one needs to create objects and object categories with precisely definable, preferably naturalistic, properties1. Furthermore, for studies on perceptual learning, it is useful to create novel objects and object categories (or object classes) with such properties2.
Many innovative and useful methods currently exist for creating novel objects and object categories3-6 (also see refs. 7,8). However, generally speaking, the existing methods have three broad types of shortcomings.
First, shape variations are generally imposed by the experimenter5,9,10, and may therefore be different from the variability in natural categories, and optimized for a particular recognition algorithm. It would be desirable to have the variations arise independently of the externally imposed constraints.
Second, the existing methods have difficulty capturing the shape complexity of natural objects11-13. If the goal is to study natural object perception, it is desirable for objects and object categories to be naturalistic, so as to avoid possible confounds and special cases.
Third, it is generally hard to quantitatively measure the available information in the stimuli created by conventional methods. It would be desirable to create objects and object categories where the available information can be precisely measured and, where necessary, systematically manipulated (or 'tuned'). This allows one to formulate the underlying object recognition tasks in quantitative terms.
Here we describe a set of algorithms, or methods, that meet all three of the above criteria. Virtual morphogenesis (VM) creates novel, naturalistic virtual 3-D objects called 'digital embryos' by simulating the biological process of embryogenesis14. Virtual phylogenesis (VP) creates novel, naturalistic object categories by simulating the evolutionary process of natural selection9,12,13. Objects and object categories created by these simulations can be further manipulated by various morphing methods to generate systematic variations of shape characteristics15,16. The VP and morphing methods can also be applied, in principle, to novel virtual objects other than digital embryos, or to virtual versions of real-world objects9,13. Virtual objects created in this fashion can be rendered as visual images using a conventional graphical toolkit, with desired manipulations of surface texture, illumination, size, viewpoint and background. The virtual objects can also be 'printed' as haptic objects using a conventional 3-D prototyper.
We also describe some implementations of these computational algorithms to help illustrate the potential utility of the algorithms. It is important to distinguish the algorithms from their implementations. The implementations are demonstrations offered solely as a 'proof of principle' of the underlying algorithms. It is important to note that, in general, an implementation of a computational algorithm often has limitations that the algorithm itself does not have.
Together, these methods represent a set of powerful and flexible tools for studying object recognition and perceptual learning by biological and computational systems alike. With appropriate extensions, these methods may also prove useful in the study of morphogenesis and phylogenesis.

We describe a novel methodology for creating naturalistic 3-D objects and object categories with precisely defined feature variations. We use simulations of the biological processes of morphogenesis and phylogenesis to create novel, naturalistic virtual 3-D objects and object categories that can then be rendered as visual images or haptic objects.

지각과 지각 학습 유학을위한 객체와 객체 카테고리 만들기

In order to quantitatively study object perception, be it perception by biological systems or by machines, one needs to create objects and object ...

연구

신경과학

The (Spatial) Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition

The memory game paradigm is a behavioral procedure to explore the relationship between language, spatial memory, and object knowledge. Using two different versions of the paradigm, spatial language use and memory for object location are tested under different, experimentally manipulated conditions. This allows us to tease apart proposed models explaining the influence of object knowledge on spatial language (e.g., spatial demonstratives), and spatial memory, as well as understanding the parameters that affect demonstrative choice and spatial memory more broadly. Key to the development of the method was the need to collect data on language use (e.g., spatial demonstratives: &#34;this/that&#34;) and spatial memory data under strictly controlled conditions, while retaining a degree of ecological validity. The language version (section 3.1) of the memory game tests how conditions affect language use. Participants refer verbally to objects placed at different locations (e.g., using spatial demonstratives: &#34;this/that red circle&#34;). Different parameters can be experimentally manipulated: the distance from the participant, the position of a conspecific, and for example whether the participant owns, knows, or sees the object while referring to it. The same parameters can be manipulated in the memory version of the memory game (section 3.2). This version tests the effects of the different conditions on object-location memory. Following object placement, participants get 10 seconds to memorize the object&#39;s location. After the object and location cues are removed, participants verbally direct the experimenter to move a stick to indicate where the object was. The difference between the memorized and the actual location shows the direction and strength of the memory error, allowing comparisons between the influences of the respective parameters.

The Spatial Memory Game: Testing the Relationship Between Spatial Language, Object Knowledge, and Spatial Cognition

We present a protocol to explore the relationship between spatial language production, spatial memory, and object knowledge. The procedure allows experimental manipulation of, and control over, conditions of object knowledge, language at instruction, and physical location, thus teasing apart cognitive and linguistic models describing interactions between these variables.

(공간) 메모리 게임: 테스트 공간 언어, 개체, 지식과 공간 인식의 관계

The memory game paradigm is a behavioral procedure to explore the relationship between language, spatial memory, and object knowledge. Using two different ...

행동분석학

A View of Their Own: Capturing the Egocentric View of Infants and Toddlers with Head-Mounted Cameras

Infants and toddlers view the world, at a basic sensory level, in a fundamentally different way from their parents. This is largely due to biological constraints: infants possess different body proportions than their parents and the ability to control their own head movements is less developed. Such constraints limit the visual input available. This protocol aims to provide guiding principles for researchers using head-mounted cameras to understand the changing visual input experienced by the developing infant. Successful use of this protocol will allow researchers to design and execute studies of the developing child&#39;s visual environment set in the home or laboratory. From this method, researchers can compile an aggregate view of all the possible items in a child&#39;s field of view. This method does not directly measure exactly what the child is looking at. By combining this approach with machine learning, computer vision algorithms, and hand-coding, researchers can produce a high-density dataset to illustrate the changing visual ecology of the developing infant.

Infants and toddlers view the world in a fundamentally different way from their parents. Head-mounted cameras provide a tractable mechanism to understand the infant visual environment. This protocol provides guiding principles for experiments in the home or laboratory to capture the egocentric view of toddlers and infants.

그들의 자신의 보기: 유아와 유아 머리 장착형 카메라의 자기 보기를 캡처

Infants and toddlers view the world, at a basic sensory level, in a fundamentally different way from their parents. This is largely due to biological ...

Defining the Role Of Language in Infants' Object Categorization with Eye-tracking Paradigms

Assessing infant category learning is a challenging but vital aspect of studying infant cognition. By employing a familiarization-test paradigm, we straightforwardly measure infants&#8217; success in learning a novel category while relying only on their looking behavior. Moreover, the paradigm can directly measure the impact of different auditory signals on the infant categorization across a range of ages. For instance, we assessed how 2-year-olds learn categories in a variety of labeling environments: in our task, 2-year-olds successfully learned categories when all exemplars were labeled&#160;or the first two exemplars were labeled, but they failed to categorize when no exemplars were labeled or only the final two exemplars were labeled. To determine infants&#8217; success in such tasks, researchers can examine both the overall preference displayed by infants in each condition and infants&#8217; pattern of looking over the course of the test phase, using an eye-tracker to provide fine-grained time-course data. Thus, we present a powerful paradigm for identifying the role of language, or any auditory signal, in infants&#8217; object category learning.

Here we present a protocol for familiarization-test paradigms which provide a direct test of infant categorization and help to define the role of language in early category learning.

눈-추적 패러다임 유아 개체 분류에서 언어의 역할을 정의

Assessing infant category learning is a challenging but vital aspect of studying infant cognition. By employing a familiarization-test paradigm, we ...

Exploring Infant Sensitivity to Visual Language using Eye Tracking and the Preferential Looking Paradigm

We discuss the use of the preferential looking paradigm in eye tracking studies in order to study how infants develop, understand, and attend to the world around them. Eye tracking is a safe and non-invasive way to collect gaze data from infants, and the preferential looking paradigm is simple to design and only requires the infant to be attending to the screen. By simultaneously showing two visual stimuli that differ in one dimension, we can assess whether infants show different looking behavior for either stimulus, thus demonstrating sensitivity to that difference. The challenges in such experimental approaches are that experiments must be kept brief (no more than 10 min) and be carefully controlled such that the two stimuli differ in only one way. The interpretation of null results must also be carefully considered. In this paper, we illustrate a successful example of an infant eye tracking study with a preferential looking paradigm to discover that 6-month-olds are sensitive to linguistic cues in a signed language despite having no prior exposure to signed language, suggesting that infants possess intrinsic or innate sensitivities to these cues.

Eye tracking studies using a preferential looking paradigm can be used to study infants&#39;&#160;emerging understanding of, and attention to, their external visual world.

아이 트래킹과 우대 보이는 패러다임을 사용하여 시각적 언어에 대한 유아감도 탐색

We discuss the use of the preferential looking paradigm in eye tracking studies in order to study how infants develop, understand, and attend to the world ...

Numerical Cognition: More or Less

Source: Laboratories of Nicholaus Noles and Judith Danovitch&#8212;University of Louisville
One of the goals of the modern education system is to teach children mathematical literacy. They are taught to add, subtract, multiply, and divide, and this base knowledge is used to support learning about geometry, algebra, calculus, physics, and statistics. School-aged children usually acquire these skills in formal educational settings, but the foundation of mathematical understanding is developed much earlier in life.
As infants, humans begin to form the rough representations that allow them to make judgments about number, and perhaps the first numerical concept that humans develop is the idea of less versus more. However, probing these concepts can be challenging, because even if babies have some understanding of number, they have very few ways of showing off what they know. What they can do is crawl, eat, cry, and sleep. Thus, researchers developed a task using this limited set of responses to investigate whether babies can mentally represent number.
This experiment demonstrates how researchers can creatively use food to study concepts of numerical cognition in infants using the method by Feigenson, Carey, and Hauser.1

Investigating Numerical Cognition More/Less in Infants

수치적 인식: 많음 또는 적음

Source: Laboratories of Nicholaus Noles and Judith Danovitch&#8212;University of Louisville
One of the goals of the modern education system is to teach ...

교육

JoVE Science Education

심리학

발달 심리학

Mutual Exclusivity: How Children Learn the Meanings of Words

Source: Laboratories of Nicholaus Noles and Judith Danovitch&#8212;University of Louisville
Humans are different from other animals in many ways, but perhaps the most important differentiating factor is their ability to use language. Other animals can communicate and even understand and use language in limited ways, but trying to teach human language to a chimp or a dog takes a great deal of time and effort. In contrast, young humans acquire their native language easily, and they learn linguistic rules without explicit instruction, which is an accomplishment that even the smartest animals cannot match.&#160;
One advantage young humans have over animals is that the human brain is especially adapted to learn new words. With only a few exposures, young children can learn new words and remember them. Perhaps more impressively, children can use what they already know to guide their future learning. For example, children treat objects as if they have only one label. So, if a child has learned the word hammer, they won&#8217;t assume an unfamiliar tool has the same name. This is the principle of mutual exclusivity.1-2
This video demonstrates children&#8217;s ability to use mutual exclusivity to match words to objects in their environment.

상호 배타성 아이들이 단어의 의미를 배우는 방법

Source: Laboratories of Nicholaus Noles and Judith Danovitch&#8212;University of Louisville
Humans are different from other animals in many ways, but ...

How Children Solve Problems Using Causal Reasoning

Source: Laboratories of Judith Danovitch and Nicholaus Noles&#8212;University of Louisville
Imagine a young child hears an adult say, &#8220;I want to watch the news,&#8221; then watches the adult press a button on the remote control. A moment later, the television screen turns on. The next day, the child wants to turn on the television screen to watch cartoons. How does the child know what to do? Is it enough to say, &#8220;I want to watch cartoons,&#8221; or is pushing the button on the remote control necessary, too? Solving this problem requires children to use the information they observed (i.e., the adult&#8217;s behaviors) to come up with a solution. In their daily lives, children encounter many situations where they need to decode cause-and-effect from complex or ambiguous observations in order to accomplish a goal.
In order to examine children&#8217;s capacity for causal reasoning, psychologists set up tasks using causal scenarios to observe how children draw conclusions and test new hypotheses about the relationships between different types of objects. In these tasks, children are shown interactions involving individual objects or sets of objects. Then, they are asked to identify and use the links between the causes and the effects to solve a problem.
This video demonstrates how to measure children&#8217;s causal reasoning about novel objects based on the methods developed by Gopnik and Sobel1 and Gopnik, Sobel, Schulz, and Glymour.2

아이들이 인과적 추론을 사용하여 문제를 해결하는 방법

Source: Laboratories of Judith Danovitch and Nicholaus Noles&#8212;University of Louisville
Imagine a young child hears an adult say, &#8220;I want to ...

Categories and Inductive Inferences

Source: Laboratories of Nicholaus Noles and Judith Danovitch&#8212;University of Louisville
It might be possible for the human brain to keep track of each individual person, place, or thing encountered, but that would be a very inefficient use of time and cognitive resources. Instead, humans develop categories. Categories are mental representations of real things that can be used for a variety of purposes. For example, individuals can use the perceptual features of animals to place them into a given category. So, upon seeing a furry, four-legged, tail-wagging, barking animal, a person can determine that it is a dog. This is one of many examples where people use perceptual similarity to fit new experiences into their existing mental representations.
However, category membership is much more than skin deep, especially for representations of animals. Frank Keil demonstrated this by using a simple, yet powerful technique that focused on the differences between natural kinds and artifacts. Natural kinds include animals and other living things, while artifacts consist largely of nonliving things, such as tables or gold bricks. In his study, Keil told children stories about natural kinds and artifacts that underwent transformations causing them to cross categorical boundaries. For example, he described a step-by-step process by which a raccoon was transformed into a creature that resembled a skunk in every way. At the end of the story, the raccoon was black with a white stripe, and it had implanted glands that made it smell like a skunk, too. He asked the children to determine whether the resulting animal was a raccoon or a skunk. He used a similar method to describe the transformation of a tire-an artifact-into a shoe. Children&#39;s responses revealed interesting developmental changes into how people think about artifacts and natural kinds.
This video demonstrates Frank Keil&#39;s transformation study.1

How Children Categorize Objects and Make Inductive Inferences

범주 및 귀납적 추론

Source: Laboratories of Nicholaus Noles and Judith Danovitch&#8212;University of Louisville
It might be possible for the human brain to keep track of each ...

Piaget's Stage 1 of Cognitive Development

The sensorimotor stage, the initial phase of Jean Piaget&#39;s theory of cognitive development, spans the first two years of a child&#39;s life. During this period, infants actively engage with their surroundings, building cognitive awareness through direct interaction with the world. This interaction is primarily based on sensory perception and motor actions, allowing infants to gradually understand basic physical properties and predict how objects interact within their environment.
Exploration Through Sensory-Motor Coordination
Infants primarily explore objects using their senses, often mouthing them to discern their texture and edibility. As their motor skills develop, particularly their ability to grasp, infants experiment with objects by shaking, banging, or dropping them to observe cause-and-effect relationships, such as the sound produced when an object strikes a surface. This stage is characterized by gradually improving the ability to combine sensory input with motor responses, enhancing the infant&#39;s capacity to interact with their environment purposefully.
Development of Object Permanence
Piaget theorized that, early in the sensorimotor stage, infants lack object permanence &#8212; the understanding that objects continue to exist even when they are no longer visible. Infants under five months generally assume that an object ceases to exist once it is out of sight. However, between five and eight months, they begin developing object permanence, considered a major cognitive milestone in infancy. Piaget investigated object permanence by presenting an infant with a toy and then hiding it under a blanket. He believed that if the infant grasped that the toy was still there, they would attempt to uncover it. Infants search for hidden objects, reflecting their emerging ability to mentally represent objects and recognize their continued existence beyond immediate visibility.
Stranger Anxiety and Schema Formation
Around the same time as object permanence develops, infants begin to exhibit stranger anxiety, a natural response of fear or discomfort when confronted with unfamiliar individuals. According to Piaget, this response arises because infants cannot yet assimilate the image of an unfamiliar person into an established mental schema, causing distress and prompting defensive reactions such as crying, clinging to caregivers, or averting their gaze. Stranger anxiety signifies the infant&#39;s growing cognitive differentiation between familiar and unfamiliar stimuli, a crucial aspect of early social development within the sensorimotor stage.

Piaget&#39;s first stage of cognitive development is the sensorimotor stage, which spans from birth to approximately two years.
During this stage, infants ...

Experience is Instrumental in Tuning a Link Between Language and Cognition: Evidence from 6- to 7- Month-Old Infants' Object Categorization

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