psychophysiology Archives - Page 3 of 7

Eye-Catching: Mobile Tech Enhances Immersive Experiments

Freed from the limitations of stationary eye tracking technology, mobile eye tracking enables researchers to study their subjects while they perform a wide range of immersive tasks in natural settings.

Sixteenth-century pediatrician Thomas Phaer mused that “the eyes are the windows to the soul.” These sensory organs and their movements certainly provide a wealth of information to researchers studying the interaction of mind and body. Eye tracking has long been a key tool of physiological and psychophysiological research, and recent developments in mobile eye tracking take this valuable data resource out of the confines of the lab and into the real world.

Freed from the limitations of stationary eye tracking technology, mobile eye tracking enables researchers to study participants while they perform a wide range of immersive tasks in natural settings. These self-contained devices come in a variety of form factors including wearable glasses that provide untethered eye tracking data acquisition in real time that can be combined with other physiological data collected during live experiments.

Today’s lightweight mobile devices can record a broad spectrum of eye tracking data, including pupil size and position, gaze path, vergence angle, and areas of interest (AOI). The latter connects stimuli to eye-movement metrics, providing data on the participant’s psychophysiological response to stimuli within their field of vision. In previous blog posts and webinars, we have explored how mobile eye tracking technology gathers this data. Numerous studies have been published that demonstrate its potential in physiological and psychophysiological research. Settings and applications include user experience, sports and physical therapy, public safety and law enforcement, driving and equipment operation, and work environments from the office to the factory floor.

Mobile eye tracking technology allowed researchers at The University of Sheffield to take their experiments to the city streets for a 2020 study into how different lighting affects cyclists navigating urban environments at night. Mobile eye tracking provided data on the gaze behavior of nocturnal cyclists in parallel with skin conductance response (SCR) to better understand how obstacle detection is influenced by variations in type, location, and level of lighting. Bicycles and their riders were equipped with a BIOPAC data acquisition unit and audio stimulation units along with a BioNomadix EDA transmitter and electrodes to record the participants’ SCR. Eye tracking data, including AOI, were synchronized with SCR data and analyzed using AcqKnowledge software to determine how the riders reacted to a variety of lighting conditions. Researchers concluded that lighting plays a significant role in riders’ comfort levels at night and that improved lighting could increase urban bicycle use.

Less intrusive by design, mobile eye tracking can provide indoor experiments with a heightened degree of immersion. A study at the University of British Columbia used mobile eye tracking glasses to create a more natural environment to investigate how the immersive effects of electronic gaming machines (EGM) impact gambling addiction. The study looked at how machine design triggered psychophysiological responses in participants by assigning various AOI to EGM screens. ECG data were recorded along with respiration effort via a BIOPAC respiration effort transducer and amplifier, which were fed to a data acquisition unit and synchronized with AOI data recorded via mobile eye tracking glasses. The study was able to successfully identify several key markers for game immersion using AOI that suggest behavioral links between immersion and gambling addiction.

Possible applications for mobile eye tracking in research continue to expand with the evolution of the technology. To learn more about recent developments in mobile eye tracking, check out our latest webinar on mobile eye tracking glasses with AcqKnowledge integration.

Learn more about how to integrate mobile eye tracking into your next research project by contacting your local BIOPAC sales representative.

Mind and Body: Signals to Enhance Your Psychophysiology Research

The human body and mind share an intrinsic link, both influencing and reflecting the health and general well-being of the other. Within the field of psychophysiology, researchers gain a wealth of insight into mental processes and disorders by studying physiological signals recorded from both the brain and body. Signals such as electrodermal activity (EDA), skin temperature (SKT), electroencephalogram (EEG), heart rate variability (HRV), and functional near-infrared spectroscopy (fNIRS) provide just a few of the tools helping us to better understand these mind-body interactions.

A wide range of research technologies has made these signals increasingly accessible in the lab as well as in everyday environments, allowing studies to place participants in increasingly naturalistic settings while gathering critical physiological data. In this way, researchers can provide a more accurate picture of how study participants react to stress and arousal, experience emotion, or interact within group environments.

One recent study used EDA and heart rate (HR) to examine the role of emotion in student success within computer-based learning environments (CBLE). As discussed in previous posts, a range of signals can be used to measure the body’s physiological response to emotion, otherwise known as “affect.” By gaining a better understanding of learners’ emotional responses to CBLE stimuli, researchers in this study hope to apply their data to improvements in CBLE design. EDA data was gathered from participants via SS57LA EDA leads while HR signals were collected with SS2LB shielded lead sets, both of which were connected to a BSL MP36 data acquisition and analysis system. Participants were shown imagery designed to evoke a negative emotional reaction before being asked to read a complex academic paper. The study was able to establish a link between the participants’ emotions and their comprehension of the reading material.

In another study, researchers used EDA and skin conductance response (SCR) to measure participants’ reactions to conditioned stimuli (CS) and unconditioned stimuli (US). The goal was to determine if fear-inducing memories could be modified either pharmacologically or through behavior modification to overcome fear. An MP36R System with AcqKnowledge software allowed analysis of SCR signals gathered via SS3LA finger transducers across a range of experiments designed to trigger fear-inducing memories. While the overall results were inconclusive, the SCR signals provided valuable feedback regarding the participants’ response to stimuli.

While EDA is a common thread through many of these psychophysiology studies, other signals provide researchers with a more complete and nuanced data set from which to draw their conclusions. Researchers exploring the factors influencing musical preferences combined EDA data with ECG and facial electromyography (fEMG) signals to assess how listeners reacted to familiar and unfamiliar musical stimuli. Data from all three signals were fed to an MP36 data acquisition and analysis system. The study found a strong correlation between musical preferences and familiarity with material as reflected by the subjects’ emotional responses.

These examples only scratch the surface of how psychophysiological research is being aided by an array of signals, all made accessible with available technology. To learn more about how to implement these signals in your next study, see BIOPAC’s Psychophysiology Applications webpage.

Contact your BIOPAC sales representative to learn more about the wide range of data-gathering tools available to help you construct your next psychophysiology study.

The Year in Review: Top Physiology and Neuroscience Research Stories 2022

Another calendar year has come and gone. COVID-19 remains a reality, but we continue to adapt to the ongoing pandemic and find new ways to overcome the challenges it poses at work, at school, at home, and in the lab. And speaking of research, 2022 proved to be a banner year for innovation and breakthroughs in the sciences, particularly in the physiological and neurological fields. Here is a quick round-up of some of the research stories that caught our attention.

Brain Implant Allows Locked-in Patient to Communicate

A man in his late 30s has been given the ability to communicate for the first time since being left in a completely locked-in state by amyotrophic lateral sclerosis (ALS). The patient, who was unable to move or even open his eyes, can communicate again thanks to a brain-computer interface (BCI) comprising two microelectrode arrays implanted in his motor cortex. The procedure was carried out by a team of researchers at the University of Tübingen in Germany. “This study answers a long-standing question about whether people with complete locked-in syndrome (CLIS) – who have lost all voluntary muscle control, including movement of the eyes or mouth – also lose the ability of their brain to generate commands for communication,” wrote Dr. Jonas Zimmermann, one of the co-authors of the study resulting from the procedure.

First Scan of Dying Human Brain Provides Insight into Near-death Experience

An EEG recording from a dying 87-year-old patient has provided researchers with the first glimpse of the neurophysiological phenomena that occur shortly after cardiac arrest. While survivors of so-called near-death experiences have anecdotally reported intense and surreal experiences that include panoramic memory review, out-of-body experiences, and other hallucinatory phenomena, little is understood about what causes such occurrences. While experiments have been carried out on animal subjects showing a hypoactive state of brain activity under such conditions, this new data provided researchers with the first evidence “that the human brain may possess the capability to generate coordinated activity during the near-death period.”

Biomembrane Research May Advance Understanding of Memory in Computers and Humans

Drawing inspiration from the living realm, scientists at the U.S. Department of Energy’s Oak Ridge National Lab are applying biological concepts to next-generation computers with implications for both human health and cutting-edge computing. Researchers were able to demonstrate that an artificial cell membrane could imitate one of the hallmarks of biological memory and learning—long-term potentiation (LTP). The study, published in the Proceedings of the National Academy of Sciences, shows for the first time that a cell membrane by itself, without the benefit of proteins or other embedded biomolecules, can carry out LPT over several hours. The pure lipid membrane, which was formed using lipid-covered water droplets, represents the first nanoscale structure in which memory can be encoded. The discovery opens the door to neuromorphic computing, which imitates the way the human brain stores and processes information and is more efficient than traditional computing.

This is just a sampling of the exciting developments catching our attention in the sciences this year. For more explorations of the intersection of cutting-edge technology, physiology, and neuroscience, join BIOPAC at the T4 Human Physiology Conference in summer 2023. And have a happy New Year!

To learn more about BIOPAC’s role in exciting breakthroughs in neuroscience and physiology, and how we can assist you in achieving your research and teaching goals, contact your local sales representative today.

Human Factors: Physiological Signals Enhance Ergonomics Research

Ergonomics plays a role in almost every aspect of human interaction with the world around us—how we work, entertain ourselves, rest, and relax. Simply put, ergonomics (sometimes termed “human factors and ergonomics” or simply “human factors”) refers to the way in which physiological and psychological principles are applied to design, particularly in ways that benefit a user’s physical and psychological well-being and productivity.

In practice, ergonomics addresses more than our physical interactions but also encompasses our mental, emotional, and interpersonal states. What unites these different applications of ergonomic theory is that they can be studied and better understood with many of the same tools and signals applied in other areas of physiological and psychophysiological research. These can include ECG, EOG, fNIRS, EEG, and EMG, to name just a few.

Ergonomics can be broken down into three primary domains. Physical ergonomics relates to how the body interacts with the physical environment, from the design of tools we use every day to the physical environments in which we live and work. Cognitive ergonomics focuses on how our mental abilities are influenced by the systems and tasks with which we are presented. Organizational ergonomics (also known as macroergonomics) explores how to optimize organizational structures, policies, and processes within various social settings, including work environments.

One example of how physiological signals are being applied in physical ergonomics research involves the application of electrooculogram (EOG) signals to analyze eye movements, particularly saccades, as a measurement of eye fatigue caused by exposure to digital screens. The ubiquity of such screens in both our work and recreational environments makes such research critical to maintaining user well-being and productivity. This 2018 study utilized EOG electrodes connected via SS2LB leads to an MP36 data acquisition unit running BSL software to record and analyze EOG signals. Researchers were able to determine the optimal reading and viewing distance to minimize eye fatigue and discomfort, improving user health and productivity.

Cognitive ergonomics come into play when discussing the ease-of-use for a product. This is particularly important when dealing with how less technologically savvy groups interact with new technology, a challenge is explored in a 2019 study into how to develop a home heart monitor that would be easy for older users to operate. The study compared user interaction with device hardware, a mobile app, and a cloud-based software platform while using a BIOPAC research-level system as a control. Researchers created the signal baseline with an ECG amplifier connected to a data acquisition and analysis unit, comparing these results to the quality of the signal the user was able to obtain using the self-administered home devices and applications. This approach accurately assesses both the user-friendliness and quality of data obtained by several telemedicine systems.

These examples offer just a small sample of the ways in which physiological signals are being applied in the study of ergonomics. For an in-depth exploration of the topic, watch our webinar series on Ergonomics and Fatigue.

To learn more about using BIOPAC hardware and software to enhance your ergonomics study or design research, contact your local sales representative.

Workflow: Research Smarter with Automated Routines

You have probably heard the saying “why work harder when you can work smarter?” While this may seem like a cliché, there is no denying that smart work, or what might be more accurately termed “efficient effort,” not only alleviates worker stress but in doing so minimizes human error while creating opportunities for increased productivity and creativity.

In an earlier post on lab automation, we discussed how increased workloads and human error have contributed to a crisis of reproducibility and repeatability in the research community. To summarize, repeatability and reproducibility provide the foundation upon which the scientific method is built. The results of academic research only retain value for the wider scientific community when the conditions that produce such results can be repeated and shared amongst other researchers.

There are several best practices that can contribute to ensuring repeatability and reproducibility of research by maintaining the conditions under which lab work is conducted. These include, among other factors, consistency in the location or research environments, the tools used for measurement as well as other equipment used in experiments, and the routines and processes used to gather and analyze data.

As discussed in the previous blog post, automation of data gathering and analysis has been one of the best ways to ensure consistency and repeatability while helping to eliminate human error, as outlined in a 2019 article on improving reproducibility in synthetic biology through automation:

“The successful implementation of automation technology can help to improve both the throughput and reproducibility of experiments, although the high cost and lack of flexibility of traditional lab automation has so far hindered their wide-spread adoption in academia. Recently though, there have been advances in automation technology that, when combined with new protocol sharing methods and protocol management systems, may allow for researchers to gain the benefits of automation.”

—Jessop-Fabre and Sonnenschein

Before when discussing how to automate routines for data acquisition and analysis, the focus has been on the use of scripts to string together processes. While this achieves the goal of creating laboratory conditions that are more readily repeatable, scripting requires a specific skill set. This brings us back to the notion of working smarter, not harder.

Previous versions of BIOPAC’s own AcqKnowledge data gathering and analysis software offered a powerful Scripting tool as an add-on licensed feature. The latest version of AcqKnowledge supports a new licensed feature with Scripting called Workflow. Workflow takes all the functionality of scripts and places it in an easy-to-use, drag-and-drop interface that requires no prior scripting knowledge.

Workflow is the embodiment of the “work smarter, not harder” philosophy, allowing users to create automated routines to process and analyze data under consistent and repeatable conditions. By speeding signal conditioning and preparation for analysis, Workflow boosts efficiency. The ability to save and share workflows makes it easier for colleagues and reviewers to replicate research conditions. BIOPAC CEO, Frazer Findlay hosted a recent webinar in which he provided a detailed introduction to creating automated routines with Workflow.

For additional information on the latest version of BIOPAC’s AcqKnowledge software as well as other research tools and how they can help streamline your lab work, contact your local sales representative.

Skin Deep: Using EDA to Measure Affective Response

We say something “gets under our skin” when it elicits an unpleasant or irritating emotional response. This connection between our skin and emotion runs deeper than a simple idiomatic expression, however. Along with performing several critical functions—protective, regulatory, and sensory—our skin provides a window into our physiological and emotional states as we respond to a range of stimuli. Electrodermal Activity (EDA) is the mechanism providing these insights.

EDA, also known as galvanic skin response (GSR), measures eccrine activity resulting from the sympathetic nervous system’s response to environmental stimulation. As a function of the autonomic nervous system, it is an involuntary response to a range of sensory inputs, including touch, sight, sound, odor, and taste. EDA regulates the rate of sweat produced by sweat glands in the extremities, particularly in the fingertips, palms, and soles of the feet.

EDA increases in conjunction with the level of stress or nervousness experienced by an individual. For this reason, it provides researchers with a valuable means of measuring affective response to external stimuli. As we explored in a previous post, affect is the measurable physiological expression of emotion. While there are numerous physiological signals that researchers can employ to measure affect, EDA in particular functions as an indicator of arousal. For this reason, EDA has become one of the most relied upon signals employed by researchers exploring psychophysiological phenomena.

A recent Slovakian study published in Adaptive Human Behavior and Physiology illustrates how EDA is commonly employed in such research. Researchers studying the influence of gender differences on reaction to violent imagery used skin conductivity response (SCR), the mechanism behind EDA, to measure levels of arousal when participants were shown images of war and sports. The goal of the study was to test the “male warrior hypothesis” (MWH). The theory suggests that men have evolved psychological mechanisms to form aggressive alliances with the goal of acquiring or protecting reproductive resources in war and that team sports stimulate that same impulse. EDA was measured using BIOPAC electrodes and leads feeding data to an MP36 data acquisition unit. While the study found that visual perception of team sports and war imagery stimulated different levels of excitement as measured by EDA in men and women, it was inconclusive in showing that sports provide a substitute for war in the sample of participants.

A study conducted at the University of Ottawa and published in the Journal of Behavior Therapy and Experimental Psychiatry used EDA to examine whether response-focused emotion regulation (RF-ER) strategies provided an effective way to control evoked emotions—specifically, does smiling make one feel better in times of heightened stress? EDA data was gathered from participants using a BIOPAC skin conductance transducer and amplifier connected to a BIOPAC data acquisition unit while participants were shown images designed to evoke both arousal and negative responses. Participants were asked to either suppress their emotional response to images or employ expressive dissonance (e.g., smile when disturbed). The results of the study shed doubt on previously held assumptions that RF-ER strategies were effective in controlling emotion.

These are just a sampling of the ways in which EDA is being used in psychophysiological research. For additional information on the background, tools, and techniques for using EDA in your studies, visit our EDA Resource Directory, read our EDA Introductory Guide. and watch Electrodermal Activity: Intro to Recording and Analysis or any of our EDA webinars.

For additional information on how BIOPAC can assist you with your research using EDA and a range of other physiological signals, contact your local sales representative.

Balancing Act: HRV Provides Critical Marker for Psychophysiological Health

Two college wrestlers square off on the mat awaiting the signal that will begin their match. To the casual observer, the outcome seems impossible to predict. Their coach, however, knows one competitor has a clear advantage—a heart rate variability level (HRV) that is higher than his opponent’s. Examining HRV data provides more than insight into athletic performance, it offers a window into a broad spectrum of functions that influence psychophysiological health.

In simple terms, HRV is the natural variation in the intervals between each heartbeat over time. Unlike a ticking clock, our hearts do not beat at a constant rate. As such, variations in heart rate can provide a wide range of valuable information on our bodily systems. This is because HRV represents a balancing act between our sympathetic and parasympathetic nervous systems, which together make up the autonomic nervous system. As we have discussed in previous posts, the autonomic nervous system controls nearly all the body’s involuntary functions.

The sympathetic nervous system is activated in times of stress or danger (i.e., the fight-or-flight response), during which our bodies sweat, our heart rates increase, and the interval between beats decreases. Conversely, the parasympathetic nervous system acts as a sort of switch, shutting down the sympathetic nervous system and activating a relaxed state (i.e., rest and digest). To do this, it releases acetylcholine, a neurotransmitter that makes the heart beat slower and at greater intervals.

When these two systems are in balance, they produce higher HRV through a more variable heart rate. Greater variability has been associated with the body’s ability to switch between these systems. Thus, HRV is used as a health marker, such that high HRV is associated with better cardiovascular health, mental focus, emotional health, stress management, and ability to recover from exercise, while low HRV is associated with inflammation, chronic fatigue, increased stress, depression, and chronic pain.

HRV has also been connected to willpower and is a predictor of persistence and self-control. HRV increases during periods of self-regulation sometimes called the “pause and plan response.” As such, HRV has been particularly useful in research into the mechanism associated with addiction. A 2019 study used HRV to explore how chronic pain patients treated with opioids could regulate drug cravings and depression through dispositional mindfulness. Electrocardiogram (ECG) data were sampled with a BIOPAC data acquisition unit while HRV was calculated with AcqKnowledge software.

Because HRV plays such a critical role in physical and psychological health, several studies have investigated how to self-regulate HRV, including examining how it is affected by posture. A 2020 study used a 2-channel BSL data acquisition unit to gather ECG data to calculate HRV for a variety of bodily positions to determine their impact.

A similar study examined the link between HRV and resilience, i.e., the individual’s ability to return to stable physical and psychological equilibrium after experiencing stress. HRV calculations were made from data gathered via a BIOPAC ECG100C ECG amplifier, RSP100C respiratory amplifier, and EDA/GSR amplifier. The study identified possible trends connecting resilience factors and HRV levels during specific stress-inducing simulations.

Calculating HRV with BIOPAC hardware and software solutions provides researchers with a myriad of psychophysiological insights for their lab work. Learn more about HRV from our Knowledge Base entry, as well as application notes on data preparation for analysis and statistical and geometric measures.

For additional information on how BIOPAC can assist you with a wide range of research and educational applications, contact your local sales representative.

Silent Partner: Autonomic Function Testing in Research

Like the inner workings of an intricate machine, most of our bodily functions operate with little or no conscious effort. That task falls to the autonomic nervous system, a sort of control system that regulates a wide range of processes, including digestion, heart rate, respiration, urination, and sexual arousal, to name a few. The autonomic nervous system also controls physiological responses to stimuli—the fight-or-flight response, and critical reflex actions like vomiting, swallowing, coughing, and sneezing.

The ability to effectively and accurately test autonomic function allows clinicians to diagnose and treat a range of ailments. Such tests can non-invasively evaluate the severity and distribution of autonomic failure, for example. Beyond these clinical applications, autonomic function testing provides valuable insight into how the body regulates and manages various critical functions and how the autonomic nervous system affects our physical and psychological health.

Autonomic function testing has been employed to examine the impact childhood trauma has on cognitive function as it relates to adolescent depression. A 2020 study published in Development and Psychopathology looked at whether economic deprivation and threat influenced cognitive processes and autonomic nervous system function connected to the severity of depression. Researchers measured study participants’ electrodermal activity (EDA), respiratory sinus arrhythmia (RSA), and electrocardiogram (ECG) data via an MP150 system. EDA was gathered using a BioNomadix wireless BN-PPGED amplifier set, while ECG and respiration (RSP) recordings were obtained with a BioNomadix wireless BN-RSPEC amplifier set. The study’s findings supported the assumption that a history of trauma and economic deprivation can lead to risk factors for youth depression.

Continuing with the theme of applying autonomic function testing to measure the effects of trauma, a 2021 study publish in Neurobiology of Stress examines autonomic function related to sex differences among individuals with posttraumatic stress disorder (PTSD). Skin conductance, blood pressure (BP), heart rate (HR), and high-frequency heart rate variability (HF-HRV) were recorded with an MP150 data acquisition system among male and female emergency personnel following trauma exposure. The results, which showed notable sex differences in autonomic functioning among trauma-exposed individuals, have implications for predicting cardiovascular risk in those with PTSD.

These are just a few examples of how autonomic function testing is being used outside of the clinical setting to shed new light on several research areas. Check out Part 1 and Part 2 of our webinars demonstrating how to use BIOPAC equipment and software in autonomic function research.

For additional information on how BIOPAC can assist you with a wide range of research and educational applications, contact your local sales representative.

Guilt Trips: Taking Measure of Our Moral Compass

“So full of artless jealousy is guilt, It spills itself in fearing to be spilt”
—Gertrude, William Shakespeare’s “Hamlet”

In Act 4 of Shakespeare’s famous tragedy, Hamlet’s mother Gertrude points out that the harder one tries to conceal guilt, the easier it is to expose. Little does she realize that she may have hit upon how future researchers approach the study of guilt in the lab. For practical purposes, it is a primary motivator in moral action and impacts how an individual responds to certain stimuli.

Psychologists have developed a myriad of tests to gauge guilt in a clinical setting such as the Test of Self-Conscious Affect (TOSCA), a multiple-choice test that tracks responses to various moral scenarios. While such techniques have been useful in linking guilt with conditions such as depression and anxiety, they have also shown their limitations in providing a deeper understanding of guilt’s influence on behavior, development, and psychological health.

In a recent BIOPAC webinar, UCSB professor Dr. Hongbo Yu addressed these limitations. Scenario-based tasks, he points out, are non-committal in examining the causes of guilt and do a poor job of measuring behavioral tendencies linked to guilt. Interaction-based research methods, however, allow participants to experience emotions in real-time, allow direct control of the causes of guilt in the lab, and allow for direct measurement of responses to stimuli.

As discussed in prior posts on affect, the body’s physiological manifestation of emotion, there is a range of methods and physiological signals available to researchers for measuring affect and gaining a better understanding of emotional states like guilt. Dr. Yu utilized eye-tracking, electrodermal activity (EDA), and functional magnetic resonance imaging (fMRI) in his examples. These are just a few of the signals currently being used in the lab to measure guilt.

One of the practical applications of guilt research is detecting when a subject is concealing the truth, as one would with a polygraph test. A recent study conducted by researchers at the University of Wisconsin-Madison’s Department of Psychology sought to gauge deception among research participants taking the Concealed Information Test (CIT). The goal was to improve upon traditional polygraph test signals such as heart rate and respiratory rate. Respiration data was gathered using a respiration transducer belt while ECG signals were collected with BIOPAC electrodes. In addition, researchers gathered EDA data using a transducer and finger electrodes. The study found that the EDA signal was significantly more effective in accurately measuring physiological responses during the test procedure.

A 2018 study by researchers at Liverpool Hope University looked at the link between guilt and aggression in children by examining activity in the autonomic nervous system during so-called “bad behavior.” The study measured respiratory sinus arrhythmia (RSA) and skin conductance in children 4–8 years old while they imagined engaging in antisocial activities. EDA and ECG signals were gathered via wireless amplifiers and fed to an MP150 data acquisition unit (superseded by the MP160) running AcqKnowledge software. The study found a linkage between physiological responses to aggression and guilt that may provide a better understanding of the mechanisms behind guilt and related behavior in early and middle childhood.

These are just a few examples of how physiological signals can be applied to measuring guilt in research. BIOPAC offers a wide range of data acquisition, stimulus presentation, and VR options suitable for creating custom guilt research environments in the lab.

For additional information, contact your BIOPAC representative to learn more about the range of signals that can be utilized to gather data on guilt and other emotional states in the lab.

Measuring Moods: Signals for Insight into Emotion

“Do you ever look at someone and wonder what is going on inside their head?”

Joy, an anthropomorphized manifestation of happiness, delivers this line at the opening of Pixar’s 2015 animated hit “Inside Out,” a film that explores the emotional struggles of its young protagonist. She could have been speaking for generations of researchers who have plumbed the depths of the human psyche for a better understanding of the mechanisms behind our feelings, moods, and emotions.

When today’s researchers talk about emotion, they typically do so in terms of affect, the underlying physiological and psychological experience of feelings and emotions as a reaction to stimuli. Affect and emotion are not the same thing, per se, but are fundamentally connected. While the feelings we describe as fear, joy, love, hate, etc. remain abstract, affect is more concrete. BIOPAC co-founder and head of R&D describes it as “the measurable quality or manifestation of emotion in the human body.”

This manifestation can be measured in the human nervous system’s response to stimuli. Depending on the nature of the stimuli and how this sensory data is interpreted by the central nervous system, an array of physiological responses can take place: heart rate changes, the stomach and muscle groups tense, skin temperature responds, triggering sweat glands, among others.

The signals corresponding to these reactions provide researchers with valuable data to help them better understand affect and emotion. These signals—electroencephalogram (EEG), electrodermal activity (EDA), electromyogram (EMG), heart rate, and respiratory rate, to name a few—can be recorded and measured using a range of currently available sensing technologies.

As an example, a 2019 study published through the Queensland University of Technology used respiration signals as a means of classification for human emotions such as happiness, sadness, surprise, disgust, fear, and anger. In the study, breathing signals, including airflow rate and volume, were acquired and recorded using a BIOPAC MP36 data acquisition unit while participants were shown seven film clips, each associated with a different emotion. The study concluded that the respiratory data was 80% effective in accurately classifying affective responses to the film stimuli.

A team of researchers at the Khwaja Fareed University of Engineering and Information Technology in Pakistan took their investigation into the connection between physiological signals and emotion a step further. They used a similar approach by measuring participant response to movie clips, however this time, four types of physiological signals were acquired, including ECG, EMG, respiration, and skin conductivity (SC). The data was acquired with a wide range of signal sensors and analyzed via a BIOPAC MP160 DAQ System.

Signal sensing technology also allows researchers to study emotion in multiple participants simultaneously, as was the case in a 2020 dyadic study of how a parent’s stress and emotional suppression affects their children. The study measured physiological responses of both parents and children using ECG and impedance cardiography (ICG) via a BIOPAC MP150 data acquisition unit.

The mysteries of human emotion are being unlocked through a growing understanding of the affective response to stimuli. For more information on how physiological signals can be gathered and analyzed for this purpose, see our app note on emotional state physiology as well as our webinar Emotion and Objective Physiological Measures.

Contact BIOPAC for the latest information on how we can help you measure affect in the lab.