EMG Archives - BIOPAC Blog

Muscles in Motion: Electromyography in Physiological Research

When we think about the human muscular system, movement often comes to mind. Activities such as running, lifting, and maintaining posture all rely on coordinated skeletal muscle activity, while cardiac muscle drives circulation and smooth muscle supports essential functions like digestion. Yet muscles do more than move us from point A to B; they also reflect what is happening inside the body. Patterns of muscle activation can reveal information about physical effort, fatigue, coordination, and recovery, as well as emotional expression, stress, and cognitive engagement. Electromyography (EMG) is a widely used technique for measuring the electrical signals generated by muscles during contraction, providing researchers with a direct and objective means to study both physiological function and the links among the nervous system, behavior, and mental state. By capturing muscle activity that may be too subtle to observe visually, EMG enables precise investigation of processes ranging from motor control and performance to emotional and stress-related responses.

There are several types of EMG, each suited to different research needs. Surface EMG (sEMG) uses small sensors placed on the skin to detect activity from nearby muscles and is the most common approach in behavioral and human performance studies. Intramuscular EMG involves inserting a fine-needle electrode directly into a muscle to record activity from specific muscle fibers, often used in clinical or specialized research settings. Facial EMG (fEMG), a form of surface EMG, focuses on facial muscles. By measuring muscle activity associated with smiling or frowning, fEMG allows researchers to study emotional responses, even when those responses are subtle or not consciously expressed.

One of the key strengths of EMG is its ease of integration with other physiological measurements. In many studies, EMG is recorded alongside electrocardiography (ECG), which measures heart activity; electroencephalography (EEG), which records electrical activity in the brain; functional near-infrared spectroscopy (fNIRS), which tracks changes in brain oxygenation; and eye tracking, which monitors visual attention and gaze patterns. By synchronizing these signals in time, researchers can better understand how different systems in the body work together. For example, combining EMG with EEG can reveal how brain activity leads to muscle movement, while pairing EMG with ECG can show how physical effort relates to heart responses during stress or exercise. This multimodal approach is central to advancing research in areas such as emotion, cognition, and human performance.

EMG also has important real-world applications. In rehabilitation, it helps clinicians monitor muscle recovery after injury. In ergonomics, it provides objective data about muscle strain in the workplace. In sports science, EMG helps optimize training and performance by identifying how and when muscles are activated. Increasingly, EMG is also used in human–machine interfaces, such as systems that allow people to control prosthetic limbs using their muscle signals. Its ability to detect fine-grained changes in muscle activity makes EMG a valuable tool across both research and applied settings.

Best practices for EMG data quality begin with careful electrode placement and attention to potential sources of noise. For sEMG and fEMG, electrodes should be placed over the “belly” of the target muscle, aligned with the muscle fibers, and spaced consistently to capture clean, interpretable signals. Gently cleaning the skin and, when appropriate, lightly abrading the surface helps reduce impedance and improve signal quality. In fEMG studies, precise and repeatable placement over well-defined facial muscles is critical, as these muscles are small and closely spaced. To minimize noise and artifacts, researchers should secure electrodes and cables to prevent movement, ask participants to limit unnecessary body motion, and ensure proper grounding of the recording system. Electrical interference from nearby equipment, power lines, or poor cable management can also contaminate EMG signals, so shielded cables and a controlled recording environment are recommended. Finally, synchronizing EMG with other physiological signals using a common acquisition system helps prevent timing errors and reduces the need for later corrections, resulting in cleaner data and more reliable conclusions.

Recent studies demonstrate how EMG continues to expand into new and innovative areas. In a study published in Results in Engineering, a team of researchers from China developed a low-computational method for recognizing hand gestures from EMG signals to improve prosthetic device control. The researchers extracted key features from EMG recordings and used a lightweight machine-learning model, a multilayer perceptron (MLP), to classify gestures in real time. EMG data were collected using a four-channel BIOPAC data acquisition system running Biopac Student Lab (BSL) software. Surface Ag/AgCl electrodes were placed on four forearm muscles to capture relevant muscular activity. The study showed that accurate gesture recognition can be achieved without heavy computational requirements, making the system more practical for everyday use. This work highlights how EMG can support the development of more responsive, accessible assistive technologies.

Another study, conducted by a team of researchers from Mahidol University in Thailand and presented in the Institute of Electrical and Electronics Engineers (IEEE) proceedings, explored how combining EMG with motion sensors can improve ergonomic assessments. Focusing on occupational health, the study integrated surface EMG with data from an inertial measurement unit (IMU), a sensor that tracks movement and orientation. The researchers used the IMU to calculate Rapid Upper Limb Assessment (RULA) scores—a common method for evaluating postural risk—while EMG data collected via a BIOPAC four-channel research system provided insight into muscle activity. By combining these measures, the team found that posture alone did not always reflect actual muscle strain. The inclusion of EMG revealed additional muscle stress that might otherwise go unnoticed, suggesting that multimodal approaches can lead to more accurate workplace assessments and better injury-prevention strategies.

Researchers from Louisiana State University and the Pennington Biomedical Research Center in Baton Rouge, Louisiana, examined how training experience influences muscle activation and fatigue during resistance exercise performed with and without blood flow restriction (BFR) in young men. The study, published in Physiological Reports, compared trained and untrained participants while they completed knee extension exercises under low-, medium-, and high-load conditions. The team used sEMG to measure muscle excitation and total muscle activation in the vastus lateralis, with participants fitted with a portable BIOPAC BioNomadix Wireless EMG system. EMG signals were sampled at 2000 Hz and analyzed using a data acquisition system with AcqKnowledge software, allowing the researchers to quantify both peak muscle excitation and overall activation across repetitions. The results showed that low-load exercise with blood flow restriction produced lower peak muscle excitation but substantially greater total muscle activation compared to traditional high-load exercise, regardless of training status. These findings suggest that low-load BFR training may provide an effective alternative for stimulating muscle adaptations while reducing mechanical stress, with potential applications in rehabilitation and strength training programs.

Taken together, these examples illustrate the versatility and effectiveness of EMG in neuroscience, psychophysiological research, and beyond. Whether used to study emotion, improve physical training and workplace safety, or develop assistive technologies, EMG provides a direct link between muscle activity and human behavior. When combined with other physiological measures, it offers a more comprehensive understanding of how the brain and body interact. As research tools and techniques continue to advance, EMG will remain an essential method for exploring brain-body connections. For additional information on how to design studies around EMG, best practices for gathering EMG data, and how to integrate EMG with other signals, check out our webinar on EMG acquisition and analysis.

If EMG will be part of your next physiological or psychophysiological research project, reach out to our knowledgeable staff, who are standing by to help you with each stage of the planning and design process.

2025: The Year in Review

As 2025 winds to a close, there is much to celebrate both here at BIOPAC and in the ever-expanding frontiers of research that our products engage with every day. Let’s take a quick look at where we have been over the past 12 months and what the future holds.

Popular Posts

Speaking of engagement, this is the time of year when we do a bit of self-assessment and revisit what topics our readers were most inspired by and most interested in. Apparently, many of our readers are closet gamers at heart, because our blog on research on game design and gaming impacts drove more eyes to our site than any other topic this year, followed by posts on cognitive neuroscience and aging and the human impact of isolation.

New Products and Updates

On the heels of the 2024 release of our flagship MP200 data acquisition and analysis system and a significant upgrade to AcqKnowledge software, 2025 concludes with another milestone: the imminent release of AcqKnowledge 6.0.2. This latest version features a host of improvements and additions, including full integration of MedelOpt+, which blends whole-head functional near-infrared spectroscopy (fNIRS) with electroencephalography (EEG) in a single, highly flexible device.

BIOPAC in the Lab

Every year, BIOPAC products continue to drive the most exciting research in physiology, psychology, and neurology, and 2025 was no different. Each month, we highlight breakthrough studies in which BIOPAC played a role in gathering and analyzing key data. These are usually centered around a theme and feature research published in the last few years. To close out the year, we like to spotlight a couple of significant studies from 2025 that didn’t get mentioned.

A collaborative study by researchers from the University of Georgia and Beijing Normal University examined how mothers and children coordinate their physiological responses during stressful interactions. Using BIOPAC data acquisition systems coupled with wireless ECG transmitters, the team simultaneously recorded cardiac activity from each participant pair as they completed structured challenge tasks. This setup provided the temporal precision needed to track changes in heart rate and moment-to-moment autonomic synchrony, revealing how caregivers and children influence one another biologically during shared stress. The study found that greater synchrony was linked to both emotional dynamics and regulatory behaviors during the tasks, highlighting the deep coupling between social relationships and physiological responses. The wireless BIOPAC configuration enabled naturalistic interaction while capturing high-quality dyadic data, a persistent challenge in synchrony research.

In its first full year of availability, the MP200 is already making waves in the research community. At Guangdong University of Science and Technology in China, researchers examined how head-shoulder posture and cervical muscle activation differ between college students with chronic neck pain (CNP) and healthy individuals. The team employed surface electromyography (sEMG) recorded with a BIOPAC MP200 data acquisition system and AcqKnowledge software. Researchers placed surface electrodes over targeted neck muscles to record raw EMG signals during various strength tests and physical tasks. Students with CNP demonstrated significantly poorer head and shoulder alignment, reduced neck extensor strength, and altered EMG activity, indicating neuromuscular dysfunction associated with pain. Findings showed the connection between altered posture and impaired muscle function in chronic neck pain. The study demonstrates the effectiveness of surface EMG to support clinical diagnosis and rehabilitation.

For more inspiration as we head into 2026, explore our webinar library for tips, tricks, and methods directly from experts across a range of research fields.

If you are planning to launch a study for 2026, now is the time to reach out to your nearest BIOPAC customer service representative for help finding the right tools to get started.

Healing Hands: EDA and Affective Touch

“Nothing eases suffering like human touch.” — Bobby Fischer

The gentle caress of a mother to her child. A reassuring pat on the shoulder from a friend. The touch of another human is one of the first forms of communication we experience in life, preceding the development of spoken language. Touch can have a remarkable effect on our emotional, psychological, and physiological states. It shapes our relationships with others and helps us build social connections.

The positive effects of touch are primarily associated with affective touch, characterized by comforting, caress-like stroking that activates C-tactile afferent (CT-afferent) neurons in the skin of mammals (including humans). Affective touch has attracted the interest of researchers seeking to decode how the sympathetic nervous system confronts and manages a variety of challenges, including pain regulation, stress management, and social interactions. The subject has drawn attention in the study of neurodevelopmental disorders, such as Autism Spectrum Disorders (ASD), where it is playing an essential role in understanding the sensory and social challenges facing individuals with atypical neurocognitive function.

While studies on touch, and affective touch specifically, utilize a range of physiological signals to gather data, electrodermal activity (EDA) has proven particularly useful in this area. Also referred to as Galvanic Skin Response (GSR), EDA provides a direct window into the sympathetic nervous system, which is responsible for emotional or affect-related arousal. When someone experiences pleasant or meaningful touch (e.g., a gentle stroke or supportive hand), the brain triggers subtle changes in sweat gland activity manifested as shifts in skin conductance. These changes occur when people aren’t fully aware of their emotional response. This makes EDA a sensitive, objective marker of how the body reacts to social and tactile experiences. In studies of affective touch, researchers track EDA to see whether a touch feels calming, engaging, or stressful, and how these responses differ across individuals or clinical groups such as autistic youth. Because EDA reflects genuine physiological arousal tied to emotional processing, it helps scientists understand the underlying autonomic mechanisms that shape how we experience social touch.

Researchers at the University of Tours in France examined how children with ASD respond to gentle, affective touch to determine whether they exhibit physiological patterns that differ from those of their neurotypical peers under the same conditions. The team measured multiple aspects of the autonomic nervous system, including EDA and electrocardiogram (ECG). These signals were collected using a BIOPAC MP36 data acquisition and analysis system to capture subtle changes in sympathetic arousal. Researchers collected EDA data using two 8 mm Ag/AgCl cup electrodes placed on the second phalanges of the index and middle fingers of the right hand. ECG was collected via two disposable vinyl electrodes placed on the sternum and on the right shoulder. The study found that autistic children exhibited atypical EDA responses, showing either blunted or inconsistent autonomic reactions relative to controls, even when their outward behavior appeared typical. These results suggest that affective touch may not regulate internal arousal in autistic children the same way it does in others, providing an essential insight for therapies and sensory-based interventions that rely on touch.

In a similar study, a team from the University of Turin in Italy explored how autistic adults process affective touch by comparing their subjective ratings of pleasantness with their physiological responses. The researchers used a BIOPAC data acquisition research system with an EDA amplifier module to record EDA. At the same time, participants received gentle, slow stroking intended to activate the brain’s affective touch pathways. The goal was to determine whether autistic adults show a mismatch between what they say they feel and how their bodies respond. The findings revealed an apparent dissociation. While autistic participants often rated the touch similarly to neurotypical participants, their EDA responses differed significantly, indicating altered sympathetic arousal. This physiological-subjective mismatch provides compelling evidence that affective touch is processed differently in ASD, which may help explain challenges with social touch and sensory integration in everyday interactions.

Researchers from the University of Liverpool and Manchester Metropolitan University examined how brief, naturalistic social touch alters brain activity, autonomic physiology, and emotion recognition performance. Although this multimodal study did not focus on an autism-only sample, it is relevant to social-touch research more broadly and provides methodological examples that apply to ASD studies. To capture changes in prefrontal cortex function, the team employed a BIOPAC fNIRS imager system, with signals sent to a data acquisition unit. Further analysis of fNIRS signals was handled via fNIRS visualization software. Both EDA and photoplethysmography (PPG) were recorded at 2 kHz, using shielded Ag/AgCl electrodes on the index and fourth fingers and a PPG sensor on the middle finger, and were acquired and analyzed in AcqKnowledge. The results showed that social touch increased prefrontal activation, modulated cardiac and vascular dynamics captured via PPG, and produced measurable changes in sympathetic arousal, as indexed by EDA. Participants also demonstrated improved emotion-recognition accuracy following touch. Together, these findings suggest that social touch engages coordinated central and peripheral systems in ways that may support social cognition and emotional understanding.

These are just a few examples of how EDA is being used in research into affective touch. For additional information on integrating EDA in your study, see our multiple webinars on the subject.

Are you designing a study into affective touch or just planning a research project that will focus on EDA? Our customer service staff can help you streamline the process to produce best possible data.

Boom! Pow! Clang! Exploring Stress Resilience with Startle Response and PPI

We have all felt that electrical jolt that comes with hearing a sudden, unexpected loud noise—the clang of a dropped cooking pan, the blast of a car horn, or the pop of a balloon. The reaction is instantaneous and nearly uncontrollable as muscles tense, eyes blink, pupils dilate, and one’s heart seems to leap from the chest. The startle response—a rapid, automatic reaction to sudden stimuli like loud noises—has a practical purpose, helping protect us from outside threats. It can also pose a danger if the response occurs while engaging in precision activities, such as driving a vehicle or operating machinery.

Within the psychophysiological field, the startle response can reveal how our brains and bodies process stress, attention, and emotional regulation. In pursuit of ways to mitigate its detrimental effects, researchers often study this reflex alongside prepulse inhibition (PPI). In this latter process, a weaker sound presented just before the startling noise reduces the strength of the response. To capture data when studying these phenomena, scientists use physiological signals such as electromyography (EMG) to measure the tiny muscle contractions around the eye during a blink, electrocardiography (ECG) for heart rate changes, electrodermal activity (EDA) for skin conductance, and respiration to track stress responses. In addition, researchers often pair these physiological measures with brain imaging techniques, like functional magnetic resonance imaging (fMRI) or electroencephalography (EEG), as well as cognitive tasks to build a complete picture of how startle responses connect with brain function and behavior.

Studies of startle response and PPI intersect with a wide range of fields, from neuroscience and psychiatry to aviation, defense, and occupational health. Clinical investigations of altered startle and PPI patterns are helping scientists uncover biomarkers of vulnerability or resilience. These studies are providing new insight into potential treatments for conditions like schizophrenia, PTSD, anxiety, and neurodegenerative disorders.

In applied contexts, like pilot training or high-stress professions, startle measures are used to understand how sudden stress impacts performance and decision-making. A study conducted by researchers at the University of Zagreb in Croatia with U.S. partners aimed to determine whether stress resilience markers, including startle response and PPI, could predict pilot performance under sudden startle events. Seventeen military pilot cadets completed baseline testing of physiological and cognitive features—including startle reflex habituation, PPI, heart rate variability (HRV), and multitasking ability—followed by flight simulator sessions with induced startle events. Physiological signals such as ECG, EMG (eye-blink startle reflex), respiration, and EDA were recorded via their respective BIOPAC amplifiers connected to a data acquisition and analysis system. Regression modeling showed that startle habituation, autonomic recovery, and cognitive task performance provided an accurate prediction of flight performance. The findings suggest that psychophysiological measures can help identify pilots who are more resistant to startle-induced performance degradation. Such insights could offer practical applications in pilot screening, training design, and aviation safety.

A team of Spanish researchers wanted to see how short-term (acute) stress affects both PPI and higher-level thinking (working memory) in healthy young adults. They used the Maastricht Acute Stress Test (MAST) to induce stress in one group, while another group did a non-stressful control task. After this, all participants heard loud noises that triggered the eye-blink startle response. In some trials, a prepulse immediately preceded the loud noise, which typically reduces the blink reflex. The startle (eye-blink) was measured from the orbicularis oculi muscle using BIOPAC Ag/AgCl electrodes connected to an Electromyography amplifier that fed data to a data acquisition system running AcqKnowledge software. This allowed the researchers to precisely record the intensity of a blink and the degree to which prepulse inhibited it. The team also tested working memory using tasks like digit span backwards and letter-number sequencing, in addition to other cognitive tests. They found that stress made startle responses stronger and reduced PPI, thereby degrading the participants’ ability to filter out the loud noise when it was preceded by a quieter one. Stress also impaired performance on working memory tasks compared to the non-stressed group. In practical terms, these results suggest that acute stress doesn’t just make one more reactive; it can interfere with basic sensory gating and cognitive control. This has implications for stressful jobs or situations (e.g., emergency responders or pilots) and possibly for understanding disorders where PPI or working memory is impaired.

These are just a few examples of how research into startle response and PPI can improve our understanding of the brain’s basic filtering and stress-response systems. The knowledge these studies provide may eventually translate into practical tools for diagnosis, prevention, and performance optimization. For additional information on research applications, check out our webinar on Startle and PPI.

Are you struggling to find the right tools to plan your startle response and PPI study? Our team of customer service experts will put you on the right path to gathering the best data possible for your research project.

Mind Over Matter: Cognitive Neuroscience and Aging

“Age is an issue of mind over matter. If you don’t mind, it doesn’t matter.” — Mark Twain.

While American author and humorist Mark Twain suggested that mental attitude could make aging less daunting, modern science shows that the changes our bodies and brains undergo over time are very real. Yet researchers are discovering that aging doesn’t have to mean inevitable cognitive decline. In fact, the growing field of cognitive neuroscience is revealing ways to track, understand, and even influence how our brains change with age, offering hope that we can preserve mental acuity, independence, and quality of life well into our later years.

When studying how aging affects the brain, cognitive neuroscience researchers use a variety of tools. In addition to standard behavioral tests like the Stroop test, n-back test, and verbal fluency exercises, which track reaction times, accuracy, and problem-solving strategies, they also rely on neuroimaging and physiological measurements to gather deeper insights. Neuroimaging techniques include electroencephalography (EEG), which monitors real-time electrical activity in the brain; functional near-infrared spectroscopy (fNIRS), which measures blood oxygen levels in specific cortical regions during cognitive tasks; and magnetic resonance imaging (MRI), which provides detailed structural and functional maps of the brain.

Other physiological signals play an essential role in this field, including heart rate variability (HRV), a key indicator of the autonomic nervous system’s ability to balance various physiological functions and handle stress. Electrodermal activity (EDA) allows researchers to track arousal among participants undergoing cognitive exercises. Electromyography (EMG) measures muscle activation during fine and gross motor tasks. Eye tracking and electrooculography (EOG) provide researchers with data on how aging impacts attention and the ability to process visual cues. Respiration and blood pressure provide vital information on vascular health, which is often linked to cognitive performance.

Taiwanese researchers from National Yang Ming Chiao Tung University in Taipei turned to HRV and fNIRS to uncover how aging and, more specifically, mild cognitive impairment (MCI), affect both brain and heart responses during cognitive tasks. Healthy young adults, cognitively healthy older adults, and older adults with MCI were asked to perform cognitive function and executive tests. Researchers recorded the participants’ prefrontal cortex (PFC) activation through changes in oxyhemoglobin using fNIRS and autonomic responses via HRV. The team gathered ECG data using a BIOPAC data acquisition module running AcqKnowledge data acquisition and analysis software, and equipped with an ECG amplifier. The study found that older adults who did not exhibit MCI showed lower global and executive cognitive performance, reduced HRV, but increased prefrontal activation. The research team interpreted this to be the result of compensatory neural effort. However, older adults with MCI showed even greater cognitive decline, but no further differences in HRV or prefrontal activation. The findings suggest that HRV and PFC activation patterns could serve as biomarkers for distinguishing healthy aging from early pathological decline.

To better understand how learning processes develop and change with age, researchers from Tilburg University in the Netherlands investigated how younger adults and older adults differ in their brain and body responses while learning a visuomotor sequence task. To capture these responses, the team measured EEG, skin conductance (EDA), heart rate, HRV, breathing rate, and eye movements during the task. Physiological data were collected using BIOPAC’s BioNomadix wireless dual ECG/respiration amplifier and PPG/EDA amplifier, which continuously recorded three-lead ECG, respiration, and EDA at 2,000 Hz, with signals processed and analyzed in AcqKnowledge software. This setup allowed the researchers to precisely synchronize physiological activity with learning performance. Both younger and older adults improved with practice, but older adults needed more trials to reach the same precision. Brainwave activity showed apparent age differences, while measures like HRV, respiration, and skin conductance did not. This suggests that EEG is a more sensitive marker of age-related learning changes and could help guide training programs for older adults.

A long-term study by researchers from Radboud University Medical Center in the Netherlands, together with UK collaborators, tracked a group of healthy older adults over nearly 11 years to see how their brain blood-flow regulation changed by their 80s. Using transcranial Doppler ultrasound to measure blood velocity in the middle cerebral arteries, the team also monitored control signals including heart rate, blood pressure, and breathing gases. Physiological data were recorded with a BIOPAC data acquisition and analysis system, with end-tidal CO₂ (EtCO₂) measured using capnography via a BIOPAC carbon dioxide measurement amplifier. The researchers found a slight decline in CO₂ reactivity but, surprisingly, an improvement in dynamic cerebral autoregulation (the brain’s ability to maintain steady blood flow despite blood pressure changes). These effects were most apparent in participants who later reported memory complaints, suggesting that while aging may reduce vascular responsiveness, the autoregulatory system may help compensate for early cognitive challenges. The findings show how vascular health in the brain relates to aging and memory, providing valuable insight for detecting early risks of dementia and shaping preventive strategies.

These studies highlight how combining brain imaging with physiological measurements is helping scientists reveal the complex relationship between aging, cognition, and overall health. Through cognitive neuroscience, researchers are identifying early signs of decline and gaining a better understanding of how the brain and body adapt over time. Research is paving the way to more effective screening, personalized interventions, and lifestyle strategies that may help people maintain mental sharpness and independence well into older age. For more information on the tools and techniques being applied to cognitive neuroscience research, see our Webinars and visit our page on Cognitive State Analysis.

Are you planning a study on how aging affects the brain or just looking to expand your cognitive neuroscience toolbox? Our customer service team is ready to help you find what you need to obtain the best possible data.

Game On: Applying Physiological Data in Video Game Design and Research

Ever since players first started feeding quarters into arcade games and began plugging in home systems in the late twentieth century, researchers have looked for practical tools for both shaping video game design and measuring their effects on players. Physiological signals filled this niche area of research. Researchers began investigating the connection between physiological science and gaming in the 1980s and 1990s, when early studies explored the effects of video games on heart rate and arousal. These first studies focused on issues such as aggression and overstimulation, but research has since expanded to encompass the cognitive and emotional aspects of gameplay. An early research project by NASA, for example, examined how biofeedback could be applied to game design to enhance traditional game control methods while also improving players’ cognitive abilities.

Today, physiological monitoring is not only a method for psychological inquiry but also a vital asset in improving user experience (UX) research, game accessibility, and even driving therapeutic game development. As wearable sensors and game engines grow more sophisticated, the integration of physiological signals into game design is opening new frontiers for immersive, responsive, and health-conscious gaming. By analyzing real-time bodily signals, such as heart rate (HR), electroencephalography (EEG), electromyography (EMG), electrodermal activity (EDA), respiration, photoplethysmography (PPG), and electrooculography (EOG), researchers and developers can gain a deeper understanding of how players emotionally and physically respond to game elements.

A study published in the International Journal of Human-Computer Studies investigated whether players’ self-reported preferences for first-person shooter (FPS) game dynamics match their emotional reactions during both gameplay and viewing. Researchers recruited 24 active gamers and divided them into two groups: those who enjoyed the fast-paced action of FPS games and those who didn’t. While participants played an FPS game and later watched a recording of it, the team measured electrodermal activity (EDA), heart rate, and facial muscle responses, specifically expressions associated with frowning (corrugator supercilii) and smiling (zygomaticus major), to capture emotional arousal and valence. Physiological signal data were recorded using BIOPAC EDA, PPG, and EMG amplifiers, which were connected to a data acquisition and analysis system running AcqKnowledge software. Although both groups reported more positive feelings and higher excitement after actively playing rather than watching, the data revealed a deeper story: players who disliked the game showed more substantial rises in arousal during play. Those who favored the dynamics, however, showed steadier emotional responses across both conditions. Muscle activity patterns also differed. Those who enjoyed FPS dynamics exhibited sharper increases in frowning-related muscle activity during play than watchers, indicating nuanced emotional engagement. Overall, the study found that what people say they prefer does reflect in their bodies’ emotional reactions. Still, those preferences also shape whether playing or spectating feels more intense, highlighting how combining self-reports with physiological signals can deepen an understanding of game design and player experience.

A team of researchers from Bournemouth University’s Centre for Digital Entertainment investigated how players’ bodies react during intense engagement, or flow, in virtual reality (VR) games. The goal was to capture objective physiological signals, such as heart rate and eye-blink patterns, alongside subjective self-reports to see how well a game’s design induced flow versus boredom or anxiety. The researchers had participants play a custom VR “tower defense” game while monitored with BIOPAC equipment, including a two-channel Biopac Student Lab (BSL) data acquisition system and physiological modules to record HRV via ECG, as well as EOG and EEG signals. The team then utilized clustering and machine-learning classifiers to decode flow states with high accuracy. The research team also successfully identified that high flow correlated with fewer blinks and longer blink intervals, indicating a state of deep concentration. The study not only demonstrates the value of combining physiological and self-report data but also shows how wearable sensors can inform design decisions in VR games by providing real-time feedback on player experience.

Beyond game design, a primary area of research focus has been on the long-term psychological, neurological, and physiological impact that games have on players. A study published in the Journal of Media Psychology explored how experiences with violent video games might reduce prosocial behavior, such as the motivation to help others, through physiological changes. Researchers recruited 155 Chinese college students who reported their exposure to violent games (in terms of violence, bloodiness, and duration) and completed simple self-reports measuring their willingness to help and the time they took to help others in controlled scenarios. Researchers used a BIOPAC data acquisition unit running AcqKnowledge software to record relevant physiological data. A three-lead ECG amplifier, respiration module, and respiration belt were used to record ECG and breathing signals across baseline, violent-film task, and during recovery periods. Researchers calculated the reduction in respiratory sinus arrhythmia (RSA), a marker of parasympathetic nervous system engagement. They found that higher levels of violent-game experience predicted less RSA reduction during stress, which in turn was linked to reduced prosocial behavior. The study’s findings suggest that playing violent video games may impair physiological readiness to respond in an empathetic manner to others, showing RSA reduction to be a key influence. The study’s findings demonstrate how physiological and psychophysiological signals provide a deeper understanding of the impacts of video games, while also guiding design decisions.

Physiological signals help researchers identify moments of excitement, stress, immersion, or frustration. Such insights are increasingly being used to refine gameplay mechanics, balance difficulty, and enhance player engagement through adaptive or personalized game experiences. They also reveal the short- and long-term effects gameplay has on both individuals and society. For more ideas on how to apply these signals in your research, visit our Webinars page for information on wearable devices, mobile data acquisition, and other helpful topics.

Are you planning a research project related to video games? Reach out to our customer service specialists to get all the help you need in mapping out and equipping your study team.

Facing Fear: Measuring What Scares Us

In many countries, October ushers in the season of ghosts, goblins, and all manner of frightening things that inhabit our deepest fears. While the popularity of Halloween reflects the thrills many derive from a good scare, facing one’s fears is not always fun and games. Our fears can protect us from danger, but they can also hamper individuals from performing the simplest tasks and negatively impact one’s quality of life and mental health.

The study of fear conditioning and fear learning sheds light on how humans and animals develop responses to threatening stimuli. Research often relies on psychophysiological measurements—techniques that capture the body’s physical responses to fear. Key among these measurements are skin conductance response (SCR), electrodermal activity (EDA), heart rate variability (HRV), respiration, and electromyography (EMG).

SCR and EDA track changes in sweat gland activity, providing a direct measure of emotional arousal when a person experiences fear. HRV and respiration rate reveal the autonomic nervous system’s reaction to stress, indicating shifts between sympathetic (fight-or-flight) and parasympathetic (rest-and-digest) states. EMG measures muscle activity, especially facial muscles, to detect subtle expressions or physical tension associated with fear. Understanding these mechanisms has practical applications in understanding and treating anxiety disorders, phobias, and post-traumatic stress disorder (PTSD). By analyzing the body’s automatic fear responses, scientists can develop targeted therapies to help individuals recondition or dampen these reactions.

A study published in the Journal of Behavior Therapy and Experimental Psychiatry used a range of indices to assess learned fear (unconditioned stimulus expectancy or US-expectancy) in individuals. These included both self-reporting and measurements of autonomic response such as skin conductance. Researchers using E-Prime Stimulus Presentation Systems, paired various neutral visual stimuli with unconditioned stimuli in the form of electrical shocks delivered via a constant voltage stimulator coupled with a BIOPAC STM100C amplifier. After a brief break, both neutral stimuli were administered without shock. Skin conductance response data was gathered and analyzed during each phase with a BIOPAC data acquisition and analysis system and software. Results showed a positive correlation between US-expectancy ratings and skin conductance response.

Researchers at the University of Bologna in Italy took a different approach to measuring the psychophysiological mechanisms of fear learning by focusing on HRV. In their study, published in the journal Psychophysiology, they explained that “understanding transient dynamics of the autonomic nervous system during fear learning remains a critical step to translate basic research into treatment of fear-related disorders.” Researchers gathered SCR and electrocardiogram (ECG) data. As with the previous study, mild electrical shocks were applied as unconditioned stimuli and paired with neutral or conditioned stimuli (CS). SCR signals were acquired using a skin conductance transducer attached to the participants’ fingertips connected to a BIOPAC EDA amplifier. ECG data was collected using disposable surface electrodes connected to an ECG100C amplifier. EDA and ECG signals were processed with a BIOPAC data acquisition and analysis system running AcqKnowledge software, which calculated HRV from the ECG data. Researchers concluded that “learned fear elicited a transient heart rate deceleration in anticipation of noxious stimuli.” They added that the study’s findings “provide a proximal measure of the involvement of cardiac vagal dynamics into the psychophysiology of fear learning and extinction, thus offering new insights for the characterization of fear in mental health and illness.”

Another study published in the journal Psychophysiology examines fear learning by applying a broad range of physiological signals and responses to determine which provides the “optimal measurement of human trace fear conditioning.” For this study, researchers compared SCR, pupil size response, heart period response (via ECG), respiration amplitude response, and electromyography (EMG) to measure participants’ responses to electrical current, audio, and visual stimulation. EDA data was gathered via a BIOPAC EDA amplifier, while ECG, EMG, and respiration data were fed to BIOPAC ECG100C, EMG100C, and RSP100C amplifiers, respectively. All data was processed using BIOPAC data acquisition and analysis systems and software. Results of the experiment suggested that startle eye-blink response through EMG provided the most sensitive metric for measuring fear conditioning.

Fear is just one of the emotions that can be studied through the body’s affective response to stimuli. Read more about the relationship between affect and emotion or watch our webinar on Emotion and Objective Physiological Measures.

Are you facing the reality of putting together your own fear-based study? Don’t be afraid to contact your local BIOPAC customer service representative for help finding the right tools for the job.

Going for Gold: Physiology Research Powers Olympic Athletes

As the world’s top athletes gather for the 2024 Olympic Games in Paris, they hope that years of rigorous preparation and training to ensure peak performance will pay off with a trip to the winner’s podium. Physiology research plays a critical role in these preparations, providing athletes and their coaches with valuable insights into how to best optimize training regimens and enhance athletic performance. With the introduction of new sports in the competition, understanding the specific physiological demands of each sport is critical. Advanced tools and techniques, like those developed by BIOPAC, allow researchers to study the body’s responses to different types of movement, providing tailored training programs that cater to the unique needs of each athlete.

A range of physiological signals is pivotal in sports and exercise research. Electromyography (EMG) is used to analyze muscle activation patterns, helping athletes refine their movements for efficiency and power. Electrodermal activity (EDA) provides insights into stress and arousal levels, which are essential for mental preparation and focus. Monitoring respiration rates and patterns can optimize breathing techniques, while electrocardiography (ECG) and heart rate variability (HRV) assess heart health and endurance capacity. By integrating these physiological signals, researchers and coaches can develop comprehensive training strategies that improve performance and minimize injury risk, giving athletes the best chance at Olympic gold.

One of the newest sports introduced at the Paris Olympics is breaking or competitive breakdancing. Olympic breaking competitions will feature teams of male and female competitors facing off with opposing teams in one-on-one dance battles. Dance, whether competitive or recreational, has been the subject of extensive study as researchers have examined this intersection of music and rhythmic bodily movement. A study published in 2021 in the journal Nature examined how younger and older adults timed bodily movement to both metronomic rhythms and music. The study compared participants’ responses to auditory cues from a metronome and music with finger tapping, toe tapping, and dance steps. The pace of whole-body stepping movements was recorded using BIOPAC heal-toe strike sensors attached to participants’ shoes with data fed to a data acquisition and analysis system running AcqKnowledge software. The study found that whole-body movement with musical accompaniment positively influenced participants’ ability to time movements accurately with encouraging implications for the treatment of rhythmically impaired individuals, such as those with developmental disorders.

Surfing debuted at the 2020 Olympics in Tokyo and is returning for the Paris games where it will be joined by two new aquatic additions, kiteboarding and kayak cross. The surfing competition for 2024 will be held in the French territory of Tahiti. Physiology studies have played a key role in preparing competitive surfers for the ultimate test of their skills. A study published in a 2021 issue of Nature investigated how surfers’ paddling cycles affect fatigue. Paddling is a primary component of a surfer’s ability to catch the best waves during competition. Researchers measured participant velocity as they paddled in a pool while tethered to a cable that measured propulsive force. Velocity data was recorded using a BIOPAC data acquisition and analysis system running AcqKnowledge. Untethered velocity was also measured using a cable-based speedometer device with data also transferred to the data acquisition system. According to the researchers, the data gathered should help in the development of “a powerful and endurable metabolic base while reducing energy cost during surfing paddling,” which could play a key role in future training programs.

Boxing’s inclusion in the Olympics dates back to the original games in Ancient Greece. Modern trainers look to research conducted in the physiology lab to enhance their fighters’ competitive edge. A 2023 study by a group of researchers in Pakistan used EMG to measure muscle activity when comparing the effectiveness of two types of punches: the jab and the cross. Researchers used a force plate to measure the impact force of each type of punch, while electrodes attached to the participants’ biceps and triceps recorded EMG data via a BIOPAC data acquisition system. While both punches delivered similar force, the triceps carried most of the workload during the jab. The research may provide insight into how to best manage fatigue during competitive bouts.

These are just a few examples of how sports physiology research powered by BIOPAC tools and techniques is preparing today’s athletes to compete at the highest levels. For additional information on how BIOPAC can help your sports-related study, see our webinars on exercise physiology using our BioNomadix and Research Ring wireless recording tools and product lines.

Are you planning sports or exercise study? BIOPAC’s regional sales reps are standing by to assist you in finding the right tools for the best results possible.

Speak Up: Physiological Signals for Speech Research

In the symphony of human communication, speech is the principal instrument. Behind every uttered word lies a complex interplay of physiological and psychological signals, each telling a unique story about the speaker’s state of mind and physical well-being. The critical data provided by these signals has become a pivotal focus in both speech research and therapy, offering useful insights into the mechanisms of verbal communication and its disorders while enhancing speech ability and overall health.

Electromyography (EMG), a technique used to measure muscle activity, plays an invaluable role in speech research by revealing the interaction of facial muscles involved in articulation. By monitoring EMG signals from muscles such as the lips, tongue, and jaw, researchers can elucidate the precise movements and coordination required for speech production, shedding light on the underlying mechanisms of speech disorders like dysarthria or apraxia.

A French study published in the 2024 edition of Science Reports used EMG to establish the role tongue reflex plays in speech posture control. The presence of a tongue reflex in maintaining tongue posture, the proper positioning of the tongue in the mouth, has been a matter of debate among speech researchers. The study team employed an unorthodox recording technique that involved attaching EMG electrodes to the base of the tongue “to record activation of the anterior genioglossus, which is responsible for the control of the anterior part of the tongue.” A robotic arm was used to rapidly stretch the tongue while researchers measured muscular reflex EMG data during the formation of various vowel sounds, which were fed to a BIOPAC EMG amplifier for signal amplification and filtering. According to the research team, the study results “represent the first physiological demonstration in humans that the tongue is driven by reflex in response to a sudden stretch.”

Electrocardiography (ECG), which measures the electrical activity of the heart, offers insights into the intricate relationship between emotion and speech. Research has shown that changes in heart rate variability (HRV) correlate with emotional arousal and cognitive load during speech tasks. By integrating ECG data with speech analysis, researchers can explore the complex connection between emotional states and linguistic expression, paving the way for emotion-aware speech synthesis systems or interventions for social communication disorders.

A 2023 study by researchers at Vanderbilt University used ECG to examine the relationship between respiratory sinus arrhythmia (RSA) on the persistence of stuttering and, specifically, the role emotional regulation plays in stuttering. Researchers measured potential differences in RSA in preschool-age children with persistent stuttering, children who recovered from stuttering, and children who do not stutter. RSA, an index of parasympathetic nervous system activity, was measured during the viewing of both neutral (baseline) and emotionally stimulating video clips and during subsequent speaking tasks. To obtain RSA for each study participant, ECG data was gathered via a BIOPAC data collection and analysis system running AcqKnowledge. A low RSA baseline is often associated with difficulty regulating emotion and, according to the study’s main hypothesis, plays a role in speech disorders like stuttering. The study’s findings supported this hypothesis, with some caveats, but the overall result demonstrated that emotional regulation could provide a promising avenue for speech therapy.

Electroencephalography (EEG), a noninvasive method for recording brain activity, offers insight into neural underpinnings of speech processing and comprehension. By analyzing EEG signals, researchers can map the spatiotemporal dynamics of neural networks involved in language processing, from phonological encoding to semantic integration. EEG-based studies offer insights into the neural signatures of speech disorders like aphasia or developmental language disorders, informing targeted therapeutic interventions and neurorehabilitation strategies. EEG has presented challenges with regard to artifacts created by participant movement during speech, but recent studies have shown promise in EEG as a speech research tool.

This is just an introduction to the signals that are being used to provide researchers with a better understanding of speech and speech pathology. For additional information on how BIOPAC products are being integrated into the study of speech, see our application note on Speech Motor Control.

Are you planning a research project focusing on speech? Our regional sales representatives are ready to help you find the right tools for your study.

Keep Your Eye on the Ball: Eye Tracking in Exercise Research

When a coach tells a player to keep their eye on the ball, they are addressing the importance of attention and focus to success, both figuratively and literally. Whether hitting a baseball, shooting a basket, or maintaining focus in an exercise routine, how we process visual information is linked to physical and mental performance, and eye tracking is the key to unlocking this relationship.

Modern eye tracking technology is revolutionizing how researchers understand human behavior, perception, and performance during physical activity. With the rise of wearable and mobile technology, eye tracking has been freed from the confines of the lab, offering real-world insights into our exercise habits and mindset. Thanks to innovators like BIOPAC partner Argus, researchers can now access eye tracking information recorded directly from the putting green, ski slope, and even the mountain biking trail.

One of the primary applications of eye tracking in exercise research lies in understanding visual attention and gaze behavior. By tracking where individuals look while engaging in physical activity, researchers can better understand how attentional focus influences performance. For instance, studies have revealed that elite athletes exhibit more focused and efficient gaze patterns, directing their attention to critical cues that enhance their performance. A 2023 study by researchers at North Carolina State University assessed the viability of using an array of mobile physiological measurement tools, including eye tracking, to measure performance optimization techniques for rock climbers. Tools included BIOPAC monitors and transmitters for wireless tracking of skeletal muscle electromyography (EMG) and eye tracking glasses to record gaze. The study affirmed that such technologies could accurately monitor multiple athletic performance metrics in even the most challenging environments.

Beyond performance enhancement, eye tracking technology holds promise in understanding the psychological aspects of exercise behavior. By examining visual attention during exercise-related stimuli such as advertisements or motivational cues, researchers can unravel the underlying mechanisms driving exercise motivation and adherence.

The same principles of eye tracking research used in fitness and physical performance-related exercise studies can be applied in other fields, such as those that examine job performance in highly stressful and physically demanding occupations, like law enforcement. A study published in the 2023 edition of the Journal of Motor Behavior explored the relationship between gaze control and decision-making by police officers in highly stressful situations. The goal was to assess how a participant’s levels of experience and training affected tactical decisions. Participants wore eye tracking glasses during a simulated traffic incident. The participants’ respiration and electrocardiogram (ECG) signals were monitored via a BIOPAC BioNomadix dual-signal wireless transmitter. Gaze-tracking data, ECG, and respiration data were fed into a BIOPAC data acquisition system for analysis. The study found that higher levels of training “led to increased processing efficiency and effective attentional control.”

The integration of eye tracking technology into exercise physiology and psychology research offers a nuanced understanding of human behavior and performance during physical activity. With wearable and mobile solutions, this technology not only expands the possibilities of research but also holds the potential for personalized programs and the enhancement of exercise experiences for individuals across a wide range of circumstances. For more information on integrating mobile eye tracking into your exercise study, see our webinars on Recording Great Data from Exercising Subjects and Eye Tracking Glasses and AcqKnowledge Integration.

Are you planning to employ eye tracking in your next exercise study? Contact our experts for assistance in selecting the best tools for gathering and analyzing exercise data with eye tracking.