BIOPAC Blog

‘Tis the Season for Stress: Research Tools for Anxious Times

Holiday-related stress is as much of a seasonal tradition as family gatherings, frantic shopping forays, and over-indulgence in food and drink. Add to this potent mixture nearly two years of pandemic-induced tension and we have a volatile cocktail of emotions and anxiety awaiting us in November and December. What better time to study the causes and effects of stress?

Research has established strong links between stress and our moods and sense of well-being, not to mention overall mental and physical health. While certain types of stress during development can teach individuals to adapt to life’s many challenges, excessive and prolonged stress is shown to contribute to chronic disease and a range of psychological disorders. According to the American Psychological Association, which conducts an annual survey monitoring stress, the COVID pandemic has had an unprecedented impact on stress levels across all demographics, particularly among young people.

The pandemic is just one of many factors driving demand for new approaches to stress research. Thankfully, researchers now have access to a myriad of technologies to support any experiment design. In a recent webinar on techniques for measuring physiological changes related to stress, BIOPAC head of European Sales, Alex Dimov, outlined a range of stress-connected physiological responses that can be measured in the lab with available technologies. These include heart rate, heart rate variability (HRV), trans-radial-ulnar electrical bioimpedance velocimetry (TREV), cardiac output, blood pressure, EDA, pulse, respiration, EMG, EEG, and functional near infrared spectroscopy (fNIRS).

One of the challenges of measuring stress in a natural environment is finding the right data gathering tools to support the mobility of test participants. A 2019 study tackled this by examining a variety of techniques for measuring stress in day-to-day life using mobile phones and wearable sensors. Settings included the lab, automobile, office, school, and other daily life locations. Along with consumer products like smartphones, smartwatches, and fitness bands, researchers also employed wearable sensors, including the BioNomadix wireless PPG transmitter to measure blood volume pulse (BVP) using a photo plethysmogram (PPG) signal. Researchers found that the BIOPAC device provided a high level of accuracy (80%) when employed outside of the traditional lab environment.

Stress research technologies are not limited to data gathering. Stimulus presentation tools offer researchers options for both inducing and alleviating stress in the lab. A 2019 University of Wisconsin study investigating the role scents can play in reducing stress utilized EDA, heart rate, and respiratory rate to measure how rose scent reduced anxiety among students taking a difficult test. Respiratory rate was measured using a BIOPAC respiratory transducer while EDA data was collected with an EDA finger transducer. Data was collected and analyzed via the Biopac Student Lab System. While rose scent was delivered using scented lotion, it should be noted that BIOPAC offers a new modular scent delivery system that is capable of delivering up to eight scents per experiment, with more than 120 scent options.

With so many data gathering tools available, planning your next experiment should not leave you feeling on edge. Let your BIOPAC sales rep help you take the stress out of stress research.

BIOPAC offers a wide array of wired and wireless equipment that can be used in your research. To find more information on solutions for recording and analyzing signals such as ECG, heart rate, respiration, and more using any platforms mentioned in this blog post, you can visit the individual application pages on the BIOPAC website.

Hitting the Mark: Using Event Markers to Improve Data Quality

Life is a series of events—some are planned while others catch us completely by surprise. This holds true in the lab where the quality of experiments and data depend on accurately identifying, tracking, and sorting key events as they occur. Events like the introduction of stimuli and a test subject’s reaction directly impact data.

In this context, we define an “event” as piece of information associated with a specific time in a waveform. An event can capture points of interest within a file (e.g., subject moved, dose added) or on a particular channel (e.g., T-wave onset).

Whether intentional or not, critical events need to be easily located and identified by those running an experiment. Event marking provides the key to this by helping researchers eliminate outlier data while making it possible to locate data that is significant to the experiment. Today’s researchers benefit from data acquisition software that offers some form of event marking functionality to easily identify, label, and categorize such events. BIOPAC’s latest build of AcqKnowledge, for example, integrates extremely easy-to-use event marking tools that enable users to mark “quick events” with a simple tap of a function/hotkey for 17 different event categories, each containing multiple types of events.

“I’m struggling to think of any time you wouldn’t be using these,” said BIOPAC Technical Support Manager David Pollock as part of the recent webinar AcqKnowledge Bootcamp: Set Up Experiments to Facilitate Data Analysis. “They are critical to being able to interpret your data after you acquire it.”

The benefits of event markers include:

Allowing researchers to differentiate stages of an experiment
Making it easy to eliminate outlier data
Allowing researchers to track and identify stimuli
Providing control over event tracking, thus eliminating errors

A Tale of Two Studies

A pair of recent studies illustrate how data acquisition software like AcqKnowledge can streamline event marking. The first sought to test the viability of various commercial-off-the-shelf ECG sensors for monitoring stress levels in participants. Test participants used a manual button to self-mark stress events triggered by mental arithmetic tasks, startle response tests, and a cold-water response test. A BIOPAC MP Research System data acquisition unit provided a clinical baseline for comparison with the pair of COTS ECG monitors. The limitations of self-reported events were revealed when participants were found to have accidentally activated the stress “clicker” about 60% of the time.

A similar 2018 John Hopkins University study avoided this problem through both automated and researcher-controlled event marking. When examining how military commanders maintain combat effectiveness while responding to a range of potentially stressful battlefield situations, researchers employed AcqKnowledge to record event marks at the onset and offset of various stimuli. Physiological data was fed to an AcqKnowledge-equipped computer via a BIOPAC DAQ connected to an STP100C digital interface module. Event markers generated by both AcqKnowledge and E-Prime allowed researchers to easily identify stimuli as well as each task the participants performed by name, start time, end time, and duration.

Not leveraging the power of event marking tools can result in key experimental events being lost in a flood of data, potentially corrupting results. Check out this video tutorial to learn more about event marking with AcqKnowledge.

Enhance Consistency with an Automated Lab Refresh

The global COVID-19 pandemic made in-person lab work impossible under many circumstances and difficult in the best of conditions. Now, as researchers and students begin to return to the lab, an opportunity presents itself for a fresh start. One way in which labs are refreshing their approach to research and education is by adding software and equipment that allows for the automation of procedures and analysis with the goal of increasing repeatability and reproducibility within experiments and research.

It’s been a challenging 18 months for science educators and those running research facilities. The global COVID-19 pandemic made in-person lab work impossible under many circumstances and difficult in the best of conditions. Now, as researchers and students begin to return to the lab, an opportunity presents itself for a fresh start. One way in which labs are refreshing their approach to research and education is by adding software and equipment that allows for the automation of procedures and analysis with the goal of increasing repeatability and reproducibility within experiments and research.

Crisis of reproducibility

The phrases “reproducibility crisis” and “replication crisis” became buzzwords in the scientific community in the 2010s, with that notoriety spilling over into both the scientific and mainstream media’s coverage of the sciences. Several high-profile scientific and sociological studies were called into question when researchers were unable to reproduce their results. In 2015, a group of psychology researchers under the moniker of the “Open Science Collaboration” found that they were only able to reproduce the findings of 68% of studies published in high-ranking peer-reviewed journals. A 2016 survey of 1,576 researchers by the journal Nature similarly found that 52% agreed that there was a “crisis” of reproducibility, though most said they still trusted published research.

The automated advantage

One step that researchers can take to ensure the reproducibility of their experiments and thereby boost the integrity of their data and conclusions is by automating procedures, workflow, and record keeping. These steps not only reduce the possibility for human error, but also provide a clear roadmap for future researchers to repeat processes in the lab to review and test results. The National Academies of Sciences, Engineering, and Medicine guide Reproducibility and Replicability in Science (National Academies Press, 2019) outlines several of the ways in which automation is being used to enhance reproducibility of research results, including record keeping, data analysis, data version control, and workflow management. The publication notes that “automated scientific workflows are essential in data-intensive and large-scale science missions that aim to be computationally reproducible.”

A 2019 study by researchers at the Indiana University School of Informatics, Computing, and Engineering employed these techniques to demonstrate “how automation can be used to address many of these factors contributing to the replication crisis.” The study focused on the controlled rearing of chicks, comparing automated and non-automated research methods. The study found that the automated tracking system allowed researchers to increase the amount of data collected from each test subject, which in turn “reduced measurement error by 60% and increased the effective size of experiments by about 300%.”

An automated refresh

BIOPAC’s AcqKnowledge data acquisition and analysis software allows labs of any size to gain the advantage of automation to improve both the efficiency and effectiveness of research. Features like Batch Processing and BIOPAC Basic Scripting help eliminate the potential for human error by consolidating multiple tasks into a single automated routine. A heightened level of standardization and consistency results in improved data quality. Adding a Basic Scripting license to AcqKnowledge 5.0.6 ensures results are reproducible regardless of who is carrying out the experiment.

The Right Tools: Streamlining Stimulus Presentation

Our nervous system processes information from a dizzying array of stimuli—visual, auditory, thermal, olfactory, and tactile, among others. How organisms respond to stimuli provides researchers with a wealth of information on how they adapt, learn, and live. The complex interaction between stimulus and response presents a myriad of challenges when it comes to creating effective stimuli in the research environment and accurately gathering data from subjects.

Today’s researchers have been gifted with a variety of stimulus presentation options to suit their individual needs. Complex experiments may call for robust solutions that integrate a wide range of stimulus presentation and data acquisition hardware and software, often from various industry leading manufacturers such as BIOPAC, E-Prime, and Cedrus. Such experiments can combine multiple stimuli with advanced stimulus controls and data gathering techniques.

Stimulus presentation, however, is not a one-size-fits-all proposition and some researchers may prefer a simpler solution that integrates visual stimulation presentation tools with powerful eye-tracking, as is available with BIOPAC’s screen-based Eye Tracking system. Additionally, AcqKnowledge now offers native integration and synchronization of stimulus presentation, eye tracking, and physiology data acquisition and analysis, all easily managed from a single application.

The seamless integration of stimulus presentation in data gathering and analysis allowed a team of researchers from the University of Connecticut and Emory University to monitor electrodermal activity (EDA) in subjects as they responded to pain stimuli induced by electrothermal grills. The goal of the study was to determine the viability of using such grills to induce pain without causing physical harm to research subjects. Researchers recorded and stored EDA signals from electrodes attached to the subjects’ fingers with a BioNomadix® wireless amplifier and MP160 data acquisition device connected to a computer running AcqKnowledge. A STMISOC programmable stimulus isolation adapter provided EP stimulation, allowing software-controlled adjustment of stimulus pulse width, repetition, and setup of an arbitrary pulse stimulus sequence via AcqKnowledge.

Using a single integrated system doesn’t necessarily equate sacrificing utility, nor does cross-platform integration need to be complicated. A group of researchers in Beijing recently explored the connection between fear response, conditioning, and memory that required the application of electrical shocks of varying intensity. A constant current STM200 stimulator delivered the shocks, in this case controlled by E-Prime software while data was collected by an MP150 running AcqKnowledge. In its current build, AcqKnowledge also integrates stimulus presentation and data acquisition, potentially streamlining the design of such an experiment.

Studies requiring the simultaneous introduction of multiple stimuli can raise the level of complexity for researchers, as it did in a recent study that examined a link between pleasant touch and scent with facial muscle activity and heart rate. Facial EMG and ECG data were collected using a BIOPAC MP Research System with a BioNomadix® wireless system connected to a computer running AcqKnowledge; current builds of the software provide full integration of scent delivery hardware.

BIOPAC’s new integrated stimulus presentation meshes seamlessly with Eye Tracking and data acquisition, providing researchers with an integrated solution to save valuable time and effort.

BIOPAC Systems, Inc. provides life science researchers and educators with data acquisition and analysis systems that inspire people and enable greater discovery about life.

Scaling Up: The Challenges of Large-Group Studies

When formulating an approach to a research study, planning experiments, and choosing the right technology for the job, size matters. Research studies with human subjects generally fall into three scale-related categories: individual, small-group, and large-group studies. When we discuss “size” in this context, we are talking about the number of subjects sampled together at one time and in one location.

Single-participant studies sample data from subjects separately while dyadic research gathers input from two subjects at the same time and place. It may be necessary, however, to take readings from three, four, or dozens of study subject simultaneously. In such cases, researchers often want to measure how the participants react to identical stimuli or the same external conditions such as those found in a classroom, courtroom, or theater setting. Researchers may also seek to measure how subjects react or interact with other members of the study group such as during business exchanges, in a meeting room environment, or in game sessions or other competitive settings.

These large-group studies present critical challenges that may not normally occur in single-participant studies. First, the stimuli to which the participants respond must be presented in a uniform and synchronous manner. Whether the stimuli are visual or auditory, thermal or olfactory, electrical or haptic, all study subjects must be able to respond to the same stimulus.

A recent study in behavioral economics measured psychophysiological reactions to various stimuli in the form of market and trading games in which multiple interactions took place between a set of “players.” Timing was critical to accurately measure the participants’ physiological responses to trades, losses, and gains. Both the presentation of stimuli and the recording of the participants’ reactions had to be precisely synchronized.

Methods for recording subjects’ response may include biopotential data such as ECG/EKG, EEG, EMG; transducer signals that can include electrodermal activity (EDA), respiration, and temperature; eye tracking; video recording; subjective response; or fNIRS, to name just a few examples. In the above study, participants were equipped with a photodiode that recorded responses during a decision-making experiment. Signals from the photodiodes were transmitted to a 16-channel BIOPAC MP150 Data Acquisition System (since replaced by the MP160 Data Acquisition System), allowing the simultaneous, synchronous recording of timing data from up to 16 subjects.

Synchronizing data is just one consideration when conducting multi-participant studies. Other logistical challenges arise when participants must interact with their surroundings. Another large-group study compared physical and psychological activity among seven-year-old elementary school children as they learned geometry through movement-based teaching methods. This presented several challenges, including the age of the subjects and the need for freedom of movement. Such problems are common to large-group studies that require multiple participants to move unimpeded by recording apparatuses. Typically, a researcher will choose between either a minimally invasive tethered device that can be wired to a data acquisition unit (e.g., BIOPAC ECG100D Smart Amplifier) or a wireless device (e.g., BIOPAC BN-ECG2 Wireless ECG Amplifier) that permits additional freedom of movement. In this study, the researchers used wearable devices to record the children’s energy expenditure, intensity of movements, EDA, body heat flux, and skin temperature.

While large-group studies present an array of unique challenges to gathering data, these challenges can be overcome through careful planning and by choosing the right tools for the job. BIOPAC offers a wide range of scalable technologies, software, and accessories for conducting research with individual subjects, pairs, or large groups that can be adapted to an array of scenarios and research settings.

Helping Students Learn Biomedical Engineering

Students entering the rigorous Biomedical Engineering (BME) discipline learn a gamut of separate physiological signals to best study healthcare applications of new technology. Simply put, as new, advanced medical devices make their way into the market, biomedical engineers are on the front lines of discovering how to best utilize these devices and corresponding software to better serve in healthcare. Well-equipped and prepared biomedical engineers study a number of signals, movements, and physiological concepts in their research, including some of the following:

Data Acquisition & Analysis Systems	Respiratory System & Pulmonary Function
Spectral Analysis & Histograms	Bioimpedance (Cardiac Output & Blood Flow)
Amplifiers, Transducers, and Calibration	Biomechanics—Angle, Acceleration, Distance, Velocity
ECG, EDA (GSR), EEG, EGG, EMG, and EOG	Physiological Control Systems
Force, Pressure, Strain, Flow, Temperature, Sound, Light	Chart, Overlap, Scope, and X/Y Displays
Brain Computer Interface	Blood Pressure & Heart Sounds
Signal Analysis & Processing	Compartmental Modeling
Filters (FIR & IIR)	Gait Analysis
Instrumentation Design

Related scientific citations are available for BME research in nearly all these areas of interest, but for students and educators, simplified practical labs can lay the groundwork for more advanced BME areas of interest, such as Gait Analysis or Brain Computer Interface (BCI). Inherent in the design of BME education is the fusion between virtual software-based analysis and physical laboratory applications—a dichotomy that favors software-based learning and research more and more. Educating students in biomechanics, biomeasurement, and biomaterials is crucial to set them up for success in the BME field, whether they go into research, education, health services, or industry. Trained biomedical engineers utilizing virtual tools in lieu of a larger laboratory instrumentation setup can save upwards of $80,000 in hardware costs for their institution. Skills taught with virtual tools are better suited to the real world “new world” of software-based analysis and signal processing.

Physiological Signal Processing Labs—colloquially known as “breadboards”—are an excellent tool to further biomedical engineering education, through both basic lessons and the physical construction of the signal processing lab device, a foray into the physical engineering side of the BME vocations. Recorded signals are analyzed and processed via Biopac Student Lab Software—a leader in BME education for university laboratories and undergraduate studies.

For example, the Biopac Student Lab Breadboard Lab Set covers lessons on constructing and running the following signal processes:

Square Wave Oscillator
Instrumentation Amplifier
Active Filter: High Pass
Active Gain Block & Low Pass
Notch Filter for 50/60 Hz Rejection
QRS Detection: Band Pass Filter
QRS Detection: Absolute Value Circuit
QRS Detection: Low Pass Filter and Overall System Test

BIOPAC also offers Biomedical Engineering curriculum for EMG-controlled robotic labs, modeling, filtering, FFT, as well as a “Best Practices for Good Data” on-demand training series on fundamentals of physiological signal processing and support for an array of BME research applications.

The benefits of this approach to BME Education help “…viscerally engage the student in an inquiry-based learning environment.”¹ Upon construction of their own Signal Processing lab, students verify signal processing models against mathematical simulations and test the models against measured signals sourced on their own bodies.

BIOPAC offers a wide array of wired and wireless equipment that can be used in your research. To find more information on solutions for recording, teaching, and analyzing Biomedical Engineering data, you can visit our product category for BME on the BIOPAC website.

¹ Alan Macy, R&D Director, BIOPAC Systems, Inc.

fNIRS and the Brain: How cognition is defined and recorded

As the most crucial organ of the human body that quintessentially defines humanity, the brain is still our greatest puzzle to solve. Medical doctors, neuroscientists, physiological scientists, and others have been trying to understand how its functions affect our actions, dating all the way back to the dark days of phrenology. In our study of the brain, the popular research is directed towards conscious thought, thinking, or the scientific term, cognition. In physical terms, the brain is separated into different areas of grey matter for different tasks, and like an electricity operator supplies a power grid with different levels of electricity on demand, regions of the brain gearing up for critical thought are saturated with fresh, oxygenated blood to boost performance: again a sign of an active cognitive state.

In modern scientific research, one of the popular means to measure this oxygenation is through Spectroscopy—more specifically, a unique field called functional near infrared spectroscopy. How does fNIRS work in measuring human cognition? These measurements are performed with optical diodes and sensors measuring a near infrared wave pattern.

Dedicated fNIRS software displaying tissue oxygenation — A graphical display of oxygenation in the prefrontal cortex

Near infrared light is sent through the skull in a spectrum that can pass through bone and tissue, and the sensors record the plots of photons absorbed by tissue or reflected back. Naturally with such a delicate subject such as the human brain, this process is both safe for the participant and painless.

The practical benefits of this spectroscopic measurement are numerous—continuous and real time values on changes in hemoglobin levels in the prefrontal cortex (measured as oxyhemoglobin [Hb] and deoxygenated hemoglobin [HbO₂]) as subjects perform different tasks, either in a stationary recording position or in a mobile experiment environment. fNIRS technology offers standalone and field-deployable technology able to determine localized brain activity. Modern recording tools such as the fNIR103M offer a wireless recording platform, so research subjects can react naturally in real-world situations outside of the lab environment while continuously recording spectroscopic data.

fNIRS is a popular signal to record simultaneously with other physiological signals such as heart rate, ECG, HRV, EMG, respiration, and more to get a clear picture of a subject’s physiological reactions. Application areas for this signal typically include pain assessment, geriatrics, attention, sports science, Human-Computer Interface, virtual reality, stress, workload assessment, and learning. Thousands of scholarly citations have been written featuring functional near-infrared spectroscopy, as studies visualize how the brain works through cognitive problems and processes. To further your physiological research, BIOPAC’s AcqKnowledge software can record multiple physiological signals at once and provide automated analysis tools for event related potentials and ensemble averaging. fNIRS easily integrates with other physiological and neurobehavioral methods of assessing brain activity, including eye tracking, pupil reflex, respiration, and electrodermal activity.

BIOPAC Systems, Inc. provides life science researchers and educators with data acquisition and analysis systems that inspire people and enable greater discovery about life. Visit us at www.biopac.com. We invite you to look at our fNIRS webinars from BIOPAC. BIOPAC also offers a line of wired and wireless fNIRS imagers for research and education.

THE BIG 3: Crucial Signals for Interdisciplinary Psychophysiology Research

This guest post was written by Michael Hogan, BIOPAC’s Southeast Regional Representative. Contact him at michaelh@biopac.com

Even trained psychologists can be daunted by the interdisciplinary applications involved with recording objective physiological data. However, it is not necessary to learn the intricacies of bio-medical engineering, physics, statistics and underlying physiological mechanisms of the body just to incorporate these objective measures into your research. With just a few key signals of interest, and a simple hardware and software setup, a trained researcher can record and interpret the objective physiological responses of participants in a physiology study.

How to get started? Begin with a protocol you are already studying and incorporate “THE BIG 3”

ECG: Electrocardiography is a biopotential, meaning direct measurement of the electrical voltage potential changes of the heart as it completes its “cardiac cycle.” Since we can record these voltage changes and graphically represent them as a waveform through analog to digital conversion, we are able to identify changes in the behavior of the heart in response to the presented stimulus. We can then establish a recurring reference point in the “R-Peak” of the QRS complex, we are able to measure the distance between these R-Peaks and establish an R-to-R interval, this measure tells us the time in-between cycles or “beats” of the heart. From one beat to the next, we can establish the participant’s heart rate. Once we have established a heart rate, we are able to extract valuable measures, such as Heart Rate Variability: how the heart rate changes over an observed set of time intervals or in response to the correlated stimulus.

Respiration: The respiration cycle is what is known as a transduced physiological signal. This means we utilize a mechanical apparatus to create a voltage potential in response to the inhalation and exhalation phases of the respiratory cycle. These voltage changes can then be measured and graphically represented as a waveform for further analysis. The respiratory cycle waveform can tell us the following:
- Respiratory rate: the number of cycles that occur within a given time interval or changes in response to a stimulus.
- Amplitude: What is the change in magnitude of the cycle, shallow vs. deep breathing.
- Respiratory Sinus Arrythmia (RSA): When collected along with an ECG signal, this analysis accounts for the changes in the participant’s heart rate as a response to the inhalation and exhalation phases of the respiratory cycle. For example, the heart rate elevates when the participant inhales and decreases when the participant exhales.

EDA: Electrodermal Activity has been adopted as the newest nomenclature for Galvanic Skin Response “GSR.” To this day EDA is touted as the best measure of sympathetic nervous system “activation.” As a derivative physiological measure, we pass a small, imperceptible current (0.5 V) into the participant’s body and measure the change from this known value as the participant responds.

As the autonomic nervous system responds to stimuli, it stimulates the eccrine glands to produce sweat. The sweat produced lowers the impedance to the current passing into the participant. We can then measure the change and extract meaningful data regarding how the participant responded to the chosen stimulus.

Skin Conductance Response (SCR): The magnitude of the response that occurred as a result of the stimulus from its onset to its peak.
Skin Conductance Level (SCL): How long it took for the response to occur following the chosen stimulus from its onset to its peak.
Recovery time: How long it takes the response to diminish and return to “baseline/normal” values.

With these “BIG 3” physiological measures we can perform hundreds of research protocols and objectively correlate patterns of behavior. Once these measures have been employed, we can integrate other measures for more comprehensive studies, such as:

EEG and fNIR for cognitive processing and learning metrics
Non Invasive Blood Pressure (NIBP) for stress and cardiovascular metrics
Facial EMG, fEMG, or Facial Coding Software for affective emotional states metrics

Visit us at www.biopac.com or click the following links for information on:

Signal-Specific Webinars
Detailed Application Notes
Signal Specific Analysis Video Tutorials
Physiological Recording Knowledge Base
Signal guides for ECG and EDA

BIOPAC Systems, Inc. provides life science researchers and educators with data acquisition and analysis systems that inspire people and enable greater discovery about life.

EEG on the Go

Not to spike our own signal about it, but we really love recording EEG. In fact, over 6,500 research & scientific citations have been published recording EEG with BIOPAC equipment. So, let’s think about EEG. Why do we love this signal and when should you be recording it? One strong reason: EEG is perfect for on the go research such as in the field studies or wireless recording of mobile subjects. Let’s dive into advanced applications of electroencephalography that researchers are using right now.

EEG is a powerful tool in the medical and research communities for measuring brain function and regional brain activity. The correlation of specific brain waves with sleep phases, emotional states, psychological profiles, and types of mental activities is the subject of thousands of scientific articles and citations. Several scientific journals are dedicated expressly to the study of EEG-related research, and what secrets this physiological signal holds. Since the discovery of EEG as a physiological signal in the 1920s, the scalp has been the traditional recording place of this signal. Flash forward several decades, and noninvasive surface EEG recording can be performed wirelessly on human participants, increasing subject mobility and freedom of motion.

Cognitive State Analysis

Multi-rhythm analysis is a very popular means to monitor subject fatigue, stress, confusion, engagement, and workload. These measurements are often taken as background cognitive state monitoring during experiments testing subject actions or responses.

Stimulus Presentation

Introducing an outside stimulus to measure deviance from baseline can produce significant findings when recording EEG, making stimulus delivery events a popular application for EEG recording.

Spectral Analysis

The power spectrum of the EEG indicates the power of each frequency component present in the source time domain waveform. For individual time epochs derived from EEG Signals, BIOPAC’s AcqKnowledge software estimates the power spectrum of that epoch to extract mean power, median frequency, spectral edge, and peak frequency.

ERP Analysis

Event-Related Potential Analysis consists of a workflow to present visual and auditory stimuli through one computer, while your data collection software records stimuli event markers (EEG) and psychological responses on another. This workflow is popular in EEG research as it aids in identifying similarities in different stimuli responses.

Evoked Responses

Evoked Responses include haptic, auditory, visual, and somatosensory evoked responses. Evoked Response studies typically measure response to stimuli and test multiple physiological responses, including but typically not limited to an EEG-based response.

EEG Filtering

EEG Filtering allows recording of single- or multi-channel montages with on-line calculation channels for Delta, Theta, Alpha, and Beta wave activity. Users can employ various transformations to filter the data off-line for further analysis.

The best way to run these specific advanced EEG analyses is with AcqKnowledge software, which can fully automate several of these functions. For more information on BIOPAC’s wide range of tools for recording, displaying, and analyzing EEG signals from human and animal subjects, including automated EEG analysis, seizure detection, evoked responses and many others, visit BIOPAC’s EEG Analysis page or view BIOPAC’s full line of electrodes, amplifiers, and wearable, wireless transmitters and loggers.

Remote Learning and Ventilator Testing: Our COVID-19 Response in 2020

A common thread uniting the world community is near-universal agreement that 2020 has been the most challenging year in decades. From young to old, life as we know it has been upended. Virtually everything we have come to take for granted, from employment, to education, socializing with friends, or buying toilet paper has been put on pause as we grapple with an implacable enemy that recognizes no political or demographic boundaries. We have had to quickly adapt and adopt common sense mitigation strategies until we prevail in the nearly year-long battle against COVID-19. And with a vaccine imminent, we are collectively answering that challenge.

When the first stay-at-home orders hit California in March of this year, BIOPAC Systems, along with hundreds of other offices in the Santa Barbara area, shut down to protect our employees. As small businesses made masks, and automakers retooled assembly lines to produce ventilators, we assessed how to best use our own resources in this pandemic.

We brought together our senior team of engineers and applied existing BIOPAC technologies for one early tool that has been instrumental in saving lives.The Ventilator Ventilation System can be used in ventilator prototyping, large-scale production testing for new ventilator manufacturing, and field testing for existing ventilators. Critical pressure and airflow measurements are tracked through the system. Test automation and workflow management is available through scripting. Technician instructions, procedures and prompts ensure the correct procedure is performed and a pass/fail audit trail is documented.

The BIOPAC Ventilator Validation Kit was used at Ford Motor Company, Virgin Orbital, NASA/STARK Industries and with others to increase their ventilator production capacity and, in Ford’s case, meet their goal of producing 50,000 ventilators for U.S. Hospitals.

As educators also struggled with changes to their classrooms with nearly all U.S. universities going to virtual learning or hybrid classroom environments, we sought to safely preserve some of the in-person learning experience.

In June, the Biopac Student Lab Practical Lab Learning Kit was released, or BSL Home. This single-channel data acquisition system preserved the lab experience even for students learning physiology from their homes; Lessons on EMG, ECG, EEG, EOG, respiration, biofeedback, and aerobic exercise are pre-configured and included with a handheld device that includes integrated hardware and software.

Watch: Live Demo: BSL Home in Action

BIOPAC offers a wide array of wired and wireless equipment that can be used in your research. To find more information on the Ventilator Validation Kit or the BSL Home Practical Lab Kit, please visit the BIOPAC website.

Photo by Long Truong on Unsplash