Name: Investigating Social Cognition in Infants and Adults Using Dense Array Electroencephalography (dEEG) (Video) | JoVE Journal
Uploaded: 2011-06-27T14:00:00.000+00:00
Duration: 12 min 48 s
Description: Learn dense array EEG protocols for studying social cognition in infants and adults. This method provides high temporal and spatial resolution for analyzing neural activity during social cognitive tasks.

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5 minutes

The manufacturer of the Geodesic Sensor Net is Electrical Geodesics, Inc (EGI). For contact information, please visit <a href="http://www.egi.com/company">http://www.egi.com/company</a>.

1. Preparing the Experimental Setup
<ol>
	<li>Prior to the participant's arrival at the lab, ensure that the Geodesic EEG System (GES) components and the experiment control computer and software (Net Station) are operating properly.</li>
	<li>Remove all unneeded and potentially distracting items from the experiment room.</li>
	<li>Set up the experiment room in accordance with the particular experimental paradigm being implemented. Here we use paradigms ranging from computer-based tasks administered via E-Prime presentation software to various parent-infant and experimenter-infant interaction paradigms.</li>
	<li>Ensure that the video cameras are charged and arrange the cameras at angles ideal for the current experimental setup.</li>
</ol>
2.	Exchanging Information
<ol>
	<li>Upon the participant's arrival at the lab, describe the Geodesic Sensor Net application protocol and explain the experiment. </li>
	<li>After ensuring that the participant has a good understanding of the experimental protocol, make sure that he or she (or his or her legal guardian) signs a consent form before proceeding with the experiment. </li>
	<li>For EEG studies, it is often useful to obtain from the participant certain information that may be expected to have an influence on the recorded electrical brain activity. For example, information about drowsiness, last meal, and last sleep might be of interest. In the Haley lab, such information is obtained by administering standardized questionnaires. To help the experiment proceed in a timely manner, it is advisable to have two experimenters present: one to administer the questionnaires, and one to carry out the HCGSN preparations detailed below.</li>
</ol>
3.	Preparing for HydroCel Geodesic Sensor Net Application
<ol>
	<li>Prepare the HydroCel Saline electrolyte solution of distilled water, potassium chloride, and baby shampoo, making sure to stir thoroughly until all of the potassium chloride is dissolved in the solution.</li>
	<li>Using a measuring tape, measure the circumference of the participant's head, recording the measurement in centimeters. </li>
	<li>Retrieve the appropriately sized HCGSN-i.e., the one that encompasses the range of head circumferences in which the participant's head circumference falls.</li>
	<li>Submerge the sensor end of the HCGSN in the electrolyte solution and allow it to soak for 5 minutes, being sure to keep the connector end away from all liquids. It is advisable to use a timer or stopwatch to guarantee accurate timing.</li>
	<li>Open the Net Station software on the control computer and begin an experimental control session to allow zero and gain measurements to be taken before connecting the HCGSN connector and collecting data.</li>
</ol>
4.	Applying the HydroCel Geodesic Sensor Net 
In order to allow for the valid and consistent analysis of collected EEG data, the net application procedure must be highly standardized. Such standardization is achieved by taking measurements of the participant's head (as described above) to ensure the accurate and consistent placement of electrodes from participant to participant. If optimal net positioning is not initially achieved, remove the net and reapply. 
<ol>
	<li>While waiting for the sensor net to finish soaking in the electrolyte solution, guide the participant into the experiment room and instruct him or her to sit on a chair. The chair should be without wheels to avoid unwanted movement during the sensor net application. In the case of an infant participant, have the infant's guardian sit on the chair with the infant sitting upright on his or her lap, holding the infant by the waist so that the infant's entire head is accessible and the infant remains still.</li>
	<li>Using a measuring tape and a china marker pencil, locate and mark the vertex by taking the following measurements: 
		<ol class="lalpha">
			<li>Ear to ear over the top of the head</li>
			<li>Nasion to inion over the top of the head</li>
		</ol>
	The vertex can be identified as the point at which these two measurements cross.</li>
	<li>Remove the sensor net from the electrolyte bucket and place it on a clean, dry towel. Gently pat the sensor net with the towel to remove excess electrolyte solution. </li>
	<li>Give the connector end of the HCGSN to the participant or to a second experimenter to hold during the net application.</li>
	<li>Pick up the HCGSN, putting both hands in the interior of the net. Hold the net such that your thumbs are pushed firmly (but gently) on either side of the central, most frontal electrode and your pinkie fingers are pushed firmly against the band connecting the most posterior row of electrodes. Be careful not to overstretch the net. Your remaining six fingers should be loose within the net to allow the center portion to fall limp.</li>
	<li>Crouch or kneel down so that you are at eye level with the participant.</li>
	<li>From back to front, pull the sensor net over the participant's head. It is often useful to have a second experimenter present when applying the sensor net on an infant participant, to distract the infant and minimize head movement.</li>
	<li>Using your fingertips, pull gently on the band of the net and adjust it so that the vertex electrode sits on the vertex point previously marked with the china marker pencil. Tighten the ear and chin straps. Inspect anatomical landmark locations and net symmetry to see whether the net is positioned correctly, and make the necessary adjustments.</li>
</ol>
5.	Measuring Electrode Impedances
EEG is measured as the potential difference (voltage) between the referenced site and the measured site. High impedance at the scalp-electrode interface causes a drop in measured voltage, attenuation of signal amplitude, and an increase in the presence of noise. While post-acquisition filtering in certain studies (e.g., conventional ERP studies) can get rid of this noise, high impedance generally compromises the fidelity of acquired EEG data. It is therefore important to make sure impedances are within the tolerable specifications before beginning to record EEG data. 
<ol>
	<li>Plug the connector end of the HCGSN into the interface cable and turn the lever to lock it in place. Turn on the camera.</li>
	<li>In the control room, open up a new session in Net Station, enter the participant's information, and click Begin Session. Because the video and dEEG signals are synched, a live video feed from the experiment room should appear on the screen.</li>
	<li>Select the Panels dropdown menu, open Impedance, and click the Measure button. A montage of the HCGSN sensor array will appear on the screen. Drag the window to the edge of the screen so that it opens up on the monitor in the experiment room.</li>
	<li>Using a disposable pipette, rake aside the participant's hair so that each electrode is seated directly on the participant's scalp.</li>
	<li>Refer to the Impedance Measurement window displaying the HCGSN montage on the monitor. Sensors that are not making good contact with the scalp will appear red. Make note of the electrode sensor numbers. Use the pipette and a small amount of the already prepared electrolyte solution to improve the impedance of these sensors. Electrodes on the montage will turn green as their impedance is improved.</li>
	<li>When impedances are satisfactory (i.e., when all electrodes on the montage are green), click the Save &amp; Close button on the Impedance Measurement window in the control room.</li>
	<li>In Net Station, open the Dense Waveform Display. Scroll through the waveforms and note any channels that are displaying high amplitude noise due to poor scalp contact.</li>
</ol>
6.	Taking Baseline Recordings
Before beginning the experimental paradigm, take some baseline dEEG recordings of the participant's resting electrical brain activity. Resting baseline recordings are important in continuous dEEG studies because there is a high degree of variability in electrical brain activity from participant to participant. As a result, most continuous dEEG studies must implement a within-subjects experimental design, analyzing the differences between each experimental condition and a pre-experiment baseline phase. For event-related EEG studies, a baseline phase may not be necessary.
<ol>
	<li>Leave the participant alone in the experiment room and instruct him or her to sit quietly and minimize movement. For infant participants, the parent/guardian should remain in the room with the infant sitting quietly in his or her lap. In the Haley lab, a movie titled Baby Mozart, an audio-visual combination of classical music and colourful moving designs, is played to ensure that infants remain calm and still. While an interactive baseline phase may not always be ideal, it can be used as a pre-baseline phase to calm the infant before taking baseline recordings.</li>
	<li>In Net Station, click the Record button to begin recording video and waveform data. On the Dense Waveform Display, event markers can be inserted to link behavioural events to electrical activity throughout the experiment. Insert a 'baseline' event marker on the waveform display. </li>
	<li>Record baseline for a standardized time period. In the Haley lab, the standard baseline phase lasts 2 minutes.</li>
</ol>
7.	Running the Experiment
In dEEG studies, it is essential to have at least two experimenters present throughout the study. One experimenter will be responsible for interacting with the participant and implementing the behavioural paradigm, while the second experimenter will monitor the Dense Waveform Display. 
<ol>
	<li>Implement the experimental paradigm.</li>
	<li>Monitor the Dense Waveform Display throughout the experiment to determine whether any channels are displaying increasing noise levels. Increasing noise may be reflective of increasing impedances. Acceptable impedance levels can be regained by using more electrolyte solution. This should be done at a break in the experimental protocol.</li>
</ol>
8.	Debriefing the Participant
<ol>
	<li>When the experiment is complete, carefully loosen and remove the HCGSN from the participant's head. Rinse, disinfect, and dry the net.</li>
	<li>Give the participant a towel with which to wipe off any excess electrolyte solution.</li>
	<li>Give the participant any remaining questionnaires that need to be completed.</li>
</ol>
9.	Analysis
The same EGI software used to acquire dEEG data is also used to analyze the data, allowing for a smooth and easy transition from data collection to data analysis. Because the HCGSN also picks up electrical noise originating from the environment, the data must first be filtered and cleaned before it can be analyzed. All of the necessary tools are included in Net Station.
<ol>
	<li>In Net Station, click on and open the Waveform Tools panel. Run the acquired data file through the filtering and artifact detection tools after setting the desired parameters. The artifact detection tool identifies spikes resulting from eye blinks or eye movements and detects bad channels. In many cases, additional hand-editing and artifact removal may be necessary (especially when working with infant populations, in which you cannot control eye blinks and movements).</li>
	<li>Segment the data so as to separate the different experimental conditions on the basis of the inserted event markers.</li>
	<li>Apply any desired analysis. In the Haley lab, frequency analysis is used to analyze how characteristic frequencies of brain activity varies between experimental conditions and between different brain regions. A decrease in wave power is potentially reflective of the increased activity of neurons in that region. </li>
</ol>
10.	Representative Data
<img src="/files/ftp_upload/2759/2759fig1.jpg" alt="EEG time series chart; electroencephalography analysis of baseline, demonstration, recall data." data-altupdatedat="1788235205000" data-alt="Figure 1"> 
Figure 1. Raw EEG waveforms showing the fluctuations in recorded voltage (μv) across time (s), at a single electrode (electrode 30). The waveforms represent data collected during the first 1000ms of each of 3 experimental phases: baseline, demonstration, and immediate recall.
<img src="/files/ftp_upload/2759/2759fig2.jpg" alt="Brain activity heat map comparison; EEG data, baseline, demonstration, immediate recall, analysis." data-altupdatedat="1788235205000" data-alt="Figure 2"> 
Figure 2. Raw data collected from the entire scalp (128-electrode montage) during three experimental phases (baseline, demonstration, immediate recall) of a participating infant. Data is presented as a topographical map and illustrates differences in surface-level brain electrical activity (μv) across brain regions and experimental phase of the puppet task.

<ol><li>Willis, W. G., Weiler, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Neural+substrates+of+childhood+attention-deficit+%2F+hyperactivity+disorder%3A+Electroencephalographic+and+Magnetic+Resonance+Imaging+evidence%5BTitle%5D)+AND+%22Developmental+Neuropsychology%22%5BJournal%5D)">Neural substrates of childhood attention-deficit / hyperactivity disorder: Electroencephalographic and Magnetic Resonance Imaging evidence.</a> Developmental Neuropsychology. 27, 135-182 (2005).</li>
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<li>Nyström, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+infant+mirror+neuron+system+studied+with+high+density+EEG%5BTitle%5D)+AND+%22Social+Neuroscience.+Special+Issue%3A+The+Mirror+Neuron+System%22%5BJournal%5D)">The infant mirror neuron system studied with high density EEG.</a> Social Neuroscience. Special Issue: The Mirror Neuron System. , 3-3 (2008).</li>
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No conflicts of interest declared.

The Hydrocel Geodesic Sensor Net from EGI constitutes a non-invasive and easy-to-apply method of obtaining dEEG data from both adult and infant participants. This technology combines high temporal and spatial resolution with an increased opportunity for mobility, making it ideal for use in complex behavioural paradigms to investigate cognitive activities that may be reflected only in subtle changes in electrical activity. Given increasing interest in investigating the development of infant cognition and the relative scarcity of brain imaging techniques suitable for use in the infant population, the use of the HCGSN is likely to increase, leading us to a deeper understanding of infant cognition.

investigating social cognition in infants and adults using dense array electroencephalography (deeg)

Investigating Social Cognition in Infants and Adults Using Dense Array Electroencephalography (dEEG)

Dense array electroencephalography (dEEG), which provides a non-invasive window for measuring brain activity and a temporal resolution unsurpassed by any other current brain imaging technology1,2, is being used increasingly in the study of social cognitive functioning in infants and adults. While dEEG is enabling researchers to examine brain activity patterns with unprecedented levels of sensitivity, conventional EEG recording systems continue to face certain limitations, including 1) poor spatial resolution and source localization3,4,2) the physical discomfort for test subjects of enduring the individual application of numerous electrodes to the surface of the scalp, and 3) the complexity for researchers of learning to use multiple software packages to collect and process data. Here we present an overview of an established methodology that represents a significant improvement on conventional methodologies for studying EEG in infants and adults. Although several analytical software techniques can be used to establish indirect indices of source localization to improve the spatial resolution of dEEG, the HydroCel Geodesic Sensor Net (HCGSN) by Electrical Geodesics, Inc. (EGI), a dense sensory array that maintains equal distances among adjacent recording electrodes on all surfaces of the scalp, further enhances spatial resolution4,5,6 compared to standard dEEG systems. The sponge-based HCGSN can be applied rapidly and without scalp abrasion, making it ideal for use with adults7,8, children9,10,11, and infants12, in both research and clinical4,5,6,13,14,15 settings. This feature allows for considerable cost and time savings by decreasing the average net application time compared to other dEEG systems. Moreover, the HCGSN includes unified, seamless software applications for all phases of data, greatly simplifying the collection, processing, and analysis of dEEG data.
The HCGSN features a low-profile electrode pedestal, which, when filled with electrolyte solution, creates a sealed microenvironment and an electrode-scalp interface. In all Geodesic dEEG systems, EEG sensors detect changes in voltage originating from the participant's scalp, along with a small amount of electrical noise originating from the room environment. Electrical signals from all sensors of the Geodesic sensor net are received simultaneously by the amplifier, where they are automatically processed, packaged, and sent to the data-acquisition computer (DAC). Once received by the DAC, scalp electrical activity can be isolated from artifacts for analysis using the filtering and artifact detection tools included in the EGI software. Typically, the HCGSN can be used continuously for only up to two hours because the electrolyte solution dries out over time, gradually decreasing the quality of the scalp-electrode interface.
In the Parent-Infant Research Lab at the University of Toronto, we are using dEEG to study social cognitive processes including memory, emotion, goals, intentionality, anticipation, and executive functioning in both adult and infant participants.

Dense array electroencephalography is being used increasingly to study social cognitive functions in infants and adults. Here we present an established methodology that represents a significant improvement on conventional methodologies for studying EEG in infants and adults.

Dense array electroencephalography (dEEG), which provides a non-invasive window for measuring brain activity and a temporal resolution unsurpassed by any ...

The overall goal of this video is to demonstrate a protocol for investigating social cognition in infants or adults using dense array electroencephalography. This is accomplished by first preparing the experimental setup for data collection and preparing the hydro cell sensor net for application. Second, the hydro cell geodesic sensor net is applied and electrode impedances are measured.Next baseline recordings are taken and the experiment is implemented. The final step of the procedure is to analyze the data. Ultimately, results can be obtained that show distinct neural activity associated with social cognitive processes through analysis of scalp surface electrical activity with high temporal resolution.Hi, my name is Kemi, a research assistant in Dr.David Haley's parent infant developmental psychobiology laboratory. Today, Joanna and I will be demonstrating this study protocol. Hi, I'm Joanna.This method can be used to answer key questions in the field of developmental neuroscience, such as how the brain uses cognition to process social stimuli. The main advantage of this technique over existing brain imaging methods and over conventional EEG systems is the high temporal resolution, the improved spatial resolution, and the ease of application of the sensor net. Hi, I'm David Haley.We use the EEG system to study brain activity in parents and infants during social and cognitive tasks Prior to the participant's arrival at the lab, ensure that the experiment control computer, the net station software, and the geodesic EEG system components are operating properly. Also, be sure to remove all unneeded and potentially distracting items from the experiment room. Set up the room in accordance with the experimental paradigm being implemented.These can range from computer-based tasks to various parent, infant and experimental infant interaction paradigms. As will be demonstrated in this video, ensure that the video cameras are charged and arrange the cameras at angle's ideal for the current experimental setup. When the participant arrives at the lab, describe the GDS sensor net application protocol and explain the details of the experiment to him or her.Ensure that the participant or his or her legal guardian has a good understanding of the experimental protocol and obtain written and informed consent before proceeding with the experiment. For EEG studies, it is often useful to obtain certain information from the participant that may be expected to have an influence on the recorded electrical brain activity. Such information can be obtained by administering standardized questionnaires to help the experiment proceed in a timely manner.It is advisable to have two experimenters present, one to administer the questionnaires and one to carry out the hydro cell geoge sensor net preparations as described in the following section of this protocol. To begin, prepare a hydro cell saline electrolyte solution of one liter of distilled water, 11 grams of potassium chloride, and five milliliters of baby shampoo, making sure to stir thoroughly until all of the potassium chloride is dissolved in the solution. Next, using a measuring tape, measure the circumference of the participant's head.Recording the measurement in centimeters, retrieve the appropriately sized hydro cell geodesic sensor net. Choose a size that encompasses the range of head circumferences in which the participant's measurement falls. Submerge the sensor end of the sensor net in the prepared electrolyte solution and allow it to soak for five minutes.Being sure to keep the connector end away from the liquid. It is advisable to use a timer or stopwatch to guarantee accurate timing. Now, open the net station software on the control computer and begin an experimental control session.Allow zero and gain measurements to be taken before connecting the sensor net connector and collecting data while waiting for the sensor net to finish soaking in the electrolyte, bring the participant into the experiment room and have him or her sit in a sturdy chair without wheels. For infant participants, have the infant's guardian sit on the chair with the infant sitting upright on his or her lap, such that the infant's entire head is accessible. Using a measuring tape and a China marker pencil, take measurements from ear to ear over the top of the head and mark the midpoint.Then measure from the NA to the inion over the top of the head. And again, mark the midpoint. The vertex can be identified as the midpoint at which the midpoints of these two measurements cross.Once it is finished soaking, remove the sensor net from the electrolyte solution and place it on a clean, dry towel. Gently pat the sensor net with the towel to remove excess electrolyte solution. Then give the connector end of the sensor net to a second experimenter to hold during the net application.Now, pick up the sensor net, putting both hands in the interior of the net. Hold the net such that your thumbs are pushed firmly but gently on either side of the central most frontal electrode, and your pinky fingers are pushed firmly against the band connecting the most posterior row of electrodes. Be careful not to overstretch the net.Your remaining six fingers should be loose within the net to allow the center portion to fall limp, crouch, or kneel down to be at eye level with the participant from back to front, pull the sensor net over the participant's head. It is often useful to have an additional experimenter present when applying the sensor net on an infant participant. To distract the infant and minimize movement using your fingertips, pull gently on the band of the net and adjust it such that the vertex electrode sits on the vertex point marked with the China marker pencil.Tighten the ear and chinstraps inspect anatomical landmark locations to see whether the net is positioned correctly and make any necessary adjustments. Before starting the behavioral experiment, the electrode impedances need to be measured. Plug the connector end of the sensor net into the interface cable.Turn the lever to lock it in place and turn on the camera. Then in the control room, open up a new session in the net station software. Enter the participant's information and click begin session.Because the video and EEG signals are synced, a live video feed from the experiment room should appear on the screen. Now, select the panel's dropdown menu, open impedance and click on the measure button. A montage of the hydro cell go dsic sensor net array will appear on the screen.Drag this window to the edge of the screen so that it opens up on the monitor in the experiment room. Assure that each electrode is seated directly on the participant's scalp. Refer to the impeded measurement window, displaying the array montage on the monitor.Sensors that are not making good contact with the scalp will appear red. Make note of these electrode sensor numbers. Now use the pipette and apply a small amount of the previously prepared electrolyte solution to improve the impedance of these sensors.Electrodes on the montage will turn green as their impedance is improved once impedances are satisfactory. For all electrodes, click the save and close button on the impedance measurement window in the control room. Now in net station, open the dense waveform display.Scroll through the waveform and note any channels that are displaying high amplitude noise due to poor scalp contact. Return to the experiment room and readjust the positioning of any noisy electrodes so that they're making direct contact with the scalp. More electrolyte solution may be needed.Resting baseline recordings are important in dense array EEG studies because there is a high degree of variability in electrical brain activity between participants. Therefore, before beginning the experimental paradigm, some baseline EEG recordings of the participant's resting electrical brain activity should be taken for infant participants. The parent or guardian should remain in the room with the infant sitting quietly in his or her lap.A movie such as Baby Mozart can be played to ensure that infants remain calm and still during this baseline phase. Baby Mozart is an audio visual combination of classical music and colorful moving designs that can be shown on the monitor in the experiment room. Now in net station, click the record button to begin recording video and waveform data on the dense waveform display event markers can be inserted to link behavioral events to electrical activity throughout the experiment.Insert a baseline event marker on the waveform display record baseline for standardized time period of about two minutes. In dense array EEG studies, it is essential to have at least two experimenters present throughout the study. One experimenter will be responsible for interacting with the participant and implementing the behavioral paradigm.The second experimenter will remain in the control room and is responsible for monitoring the video feed and inserting event markers on the dense waveform display when a relevant event occurs. Now begin the behavioral experiment using a face-to-face interaction paradigm for the infant participant. Here, an imitation paradigm is implemented in which the experimenter presents the infant with a number of discreet actions using a rabbit puppet.Be sure to monitor the dense waveform display throughout the experiment to determine whether any channels are displaying increasing noise levels. When the experiment is complete, carefully loosen and remove the sensor net from the participant's head. Provide a towel with which to wipe off any excess electrolyte solution.Then rinse, disinfect, and dry the net. Finally, give the participant any remaining questionnaires that need to be completed as part of the protocol. These raw EEG wave forms show the fluctuations in recorded voltage at a single electrode during the first 1000 milliseconds of each of the three experimental phases.Baseline demonstration and immediate recall differences. In surface level brain electrical activity across brain regions can also be visualized as a topographical map of voltage amplitudes. Amplitudes are represented over the entire surface of the head during the three phases of the mitten shake paradigm and units of the color spectrum are in microvolts.After watching this video, you should have a good understanding of how to study social cognition in adults and infants using high density EEG. We have demonstrated this through preparation and application of the sensor net and through acquisition and analysis of EEG data.

investigating-social-cognition-infants-adults-using-dense-array

Research

JoVE Journal

Neuroscience

In recent years, there has been increasing interest in estimating the cortical sources of scalp measured electrical activity for cognitive neuroscience experiments. This article describes how high density EEG is acquired and how recordings are processed for cortical source estimation in children from the age of 2 years at the London Baby Lab.

Cortical Source Analysis of High-Density EEG Recordings in Children

High-density electroencephalography (dEEG) is being used increasingly to study brain development and plasticity in the early years of life. Here we present an application of sophisticated analysis techniques that builds on traditional EEG recording to understand the oscillatory dynamics of rapid auditory processing in the infant brain.

Infant Auditory Processing and Event-related Brain Oscillations

Stereotactic Electroencephalography (SEEG) is an operative technique used in epilepsy surgery to help localize seizure foci. It also affords a unique opportunity to investigate brain function. Here we describe how SEEG can be used to investigate cognitive processes in human subjects.

Investigating the Function of Deep Cortical and Subcortical Structures Using Stereotactic Electroencephalography: Lessons from the Anterior Cingulate Cortex

This protocol presents a novel methodology for the neural decoding of intent from freely-behaving infants during unscripted social interaction with an actor. Neural activity is acquired using non-invasive high-density active scalp electroencephalography (EEG). Kinematic data is collected with inertial measurement units and supplemented with synchronized video recording.

A Novel Experimental and Analytical Approach to the Multimodal Neural Decoding of Intent During Social Interaction in Freely-behaving Human Infants

This novel protocol is designed to assess the neural bases of social interaction in infants. The paradigm is designed to tease apart how various social inputs such as language, joint attention, and face-to-face interaction relate to infant neural activation. Infant EEG power is recorded during both social and nonsocial conditions.

A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG

Here, we show how to apply amplitude-integrated electroencephalography to monitor cerebral function in neonates.

Application of an Amplitude-integrated EEG Monitor (Cerebral Function Monitor) to Neonates

This protocol describes key steps involved in assessing the sensitivity of the brain of one person to the stimulus processing of a close other by selecting pairs of partners, recording their electroencephalogram (EEG) simultaneously and computing their event-related brain potentials (ERPs).

 How to Find Effects of Stimulus Processing on Event Related Brain Potentials of Close Others when Hyperscanning Partners

This protocol describes how synchronized electroencephalography, electrocardiography, and behavioral recordings were captured from infant-caregiver dyads in a home setting.

Home-Based EEG Hyperscanning for Infant-Caregiver Social Interactions

The procedure described in this protocol shows that testosterone administration and folk beliefs about testosterone may be associated with directly opposed social behaviors.

Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making

The assessment and treatment of pain in infants is difficult because infants cannot verbally report their experience. In this video we describe quantitative electrophysiological methods and analysis techniques that can be used to measure the response to noxious events from the infant nervous system.

Electrophysiological Measurements and Analysis of Nociception in Human Infants

Learn dense array EEG protocols for studying social cognition in infants and adults. This method provides high temporal and spatial resolution for analyzing neural activity during social cognitive tasks.

Investigating Social Cognition in Infants and Adults Using Dense Array Electroencephalography (_dEEG)

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