Is it possible to measure non-material things like thoughts or emotions using scientific methods?

The breakthrough is the first to demonstrate how a person’s intention to say specific words can be gleaned from brain signals and turned into text fast enough to keep pace with natural conversation.Neuroscientists decoded people’s thoughts using brain scans. The method captured the gist of what three people thought, but only if they wanted it to

Researchers tried to compare the electrical activity inside our brains while gazing out upon the same scene, and running some statistical analysis designed to actually tell us whose brain activity indicates more richness(6).

 One of the newest frontiers in the science of the mind is the attempt to measure consciousness’s “complexity,” or how diverse and integrated electrical activity is across the brain. Philosophers and neuroscientists alike hypothesize that more complex brain activity signifies “richer” experiences.

The idea of measuring complexity of brain processes stems from information theory — a mathematical approach to understanding how information is stored, communicated, and processed.

The approach to understanding richness is to look at how it changes in different mental states. Recent studies have found that measures of complexity are lowest in patients under general anesthesia, higher in ordinary wakefulness, and higher still in psychedelic trips, which can notoriously turn even the most mundane experiences — say, my view of the parking lot outside my office window — into profound and meaningful encounters.

Increasing richness isn’t just like cranking up the colour saturation of a picture or getting a bigger hard drive. It seems to imply an increase in the depth of how we experience the world. Complexity is what you see in the equations, richness is what that feels like in the mind.

Although measuring brain complexity is still in relative infancy, the nascent ability to gauge something like richness is a pretty incredible development — not only for neuroscience but for how we think about well-being more broadly. With innovations like these, we can go beyond the blurry questions of happiness, which doesn’t have an accepted neurological measure that can translate across social and cultural differences, and ask more targeted questions, like whether our experiences are richer. As these approaches mature, scientists might develop a deeper understanding of all the different, tractable ways that consciousness can change for the better.

Recent improvements to electroencephalography (EEG, those skull caps with a bunch of electrodes that measure the brain’s electrical activity) made it possible to look deeper inside the workings of the brain, opening the way for neuroscientist Giulio Tononi and biologist Gerald Edelman’s 1998 paper: Consciousness and Complexity.

Their publication was the first to propose a direct measure of the complexity of brain activity, an idea that matured into Integrated Information Theory, or IIT. According to IIT, consciousness arises where the underlying neural activity is both “integrated” and “differentiated.” Integration refers, roughly, to how synchronized electrical activity is across the brain. Differentiation is the diversity of that activity. You can think of them in terms of weaving a tapestry. Integration is how many different threads are woven in, while differentiation is the variety of colors used. Together, these two determine the complexity of a given state of consciousness. That, in turn, approximates its richness

The brain is constantly buzzing with electrical activity. Here's how scientists study the signals (7):  Electricity is the language of the brain. Continuously, electrical impulses, also known as action potentials, are buzzing around between your ears. Your neurons, and the synaptic junctions where neurons meet, are bathed in a chemical bath — in the form of neurotransmitters like dopamine — that mediate the electrical activity in their neighboring cells. This is the reductive basis of neurological communication, and somewhat mysteriously, these interactions underpin every thought, feeling, or action you have ever experienced.

But as scientists have learned more about the brain, they’ve noticed that large-scale states of brain activity are also important in its overall function. Different regions of the brain are known to synchronize as they fire neurons in tandem at different frequencies. These neural oscillations, or brain waves, are thought to facilitate communication between different regions of the brain. That means that scientists need to look at all scales of brain activity, both at the cellular level and within these larger networks, in grappling with the task of understanding consciousness: If we focus too closely on, say, the individual firing of neurons, then we risk missing the bigger picture, like mistaking a single drop of water for the entirety of the ocean.

One of the most widely-used methods for generating data on the brain while people carry out certain cognitive or behavioural tasks is functional magnetic resonance imaging, or fMRI. This non-invasive neuroimaging technique is a go-to for cognitive neuroscientists, largely because of the practical ease with which it can generate data. But fMRI doesn’t actually measure electrical activity in the brain; rather, it measures the indirect consequence of neural activity. Namely, where oxygenated blood is flowing.

 Meanwhile, blood oxygenation, also known as the hemoglobin response, is thought to be most tightly coupled with specific synaptic events that play a significant role in neurological communication. 

Much like a digital camera or computer screen, an fMRI brain scan can be defined in units of spatial resolution, but with images in 3D, rather than 2D. These volumetric pixels are called voxels; in a typical scan a voxel might cover 3 cubic millimeters of tissue, a volume that would carry approximately 630,000 neurons.

Few brain scanning methods have better spatial resolution than fMRI, barring intracranial recordings like electrocorticography (ECoG) that can isolate activity from single cells. But these invasive techniques, where electrodes are placed directly on the brain, are limited to animal models or specific clinical contexts where patients suffer from conditions like epilepsy that require a high level of precision when locating seizures. By contrast, fMRI strikes a good balance between precision and coverage.

However, you can measure the quantity of thought activity in a brain  but what about the quality of those thoughts? 

What are good thoughts? That is a measure which is highly subjective. Of Course there are some guidelines that originated in the cultures and societies we live in.  Thoughts that are useful to everyone around are good and selfish ones are bad. But that good and selfish are again subjective in nature. So the measurements become  somewhat hazy and still in experimental stages. 

Now let us deal with emotions and feelings.

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Emotions are intense, instinctual responses that arise from the brain’s subcortical regions, serving as our immediate reaction to stimuli. Feelings, on the other hand, are our subjective interpretations of these emotions, shaped by personal experiences, thoughts, and social conditioning, and are processed in the neocortical regions of the brain. Understanding the “difference between feelings and emotions” provides valuable insights into human behavior, offering a window into the complexity of our internal worlds and how these worlds influence our external actions.

Human feelings cannot be expressed properly on a numerical scale. There are no units of measurement for feelings. However, such data is extensively collected in the modern world—by governments, corporations, and international organizations (like my happiness is X out of 10). Humans somehow manage to choose their numerical answers in a systematic way as though they sense within themselves—and can communicate—a reliable numerical scale for their feelings. How remains an unsolved puzzle.

Human feelings measured in integers (my happiness is an 8 out of 10, my pain 2 out of 6) have no objective scientific basis. They are “made-up” numbers on a scale that does not exist. Yet such data are extensively collected—despite criticism.

Researchers show that a single feelings integer has greater predictive power than does a combined set of economic and social variables. There is also a clear inverse relationship between feelings integers and subsequent get-me-out-of-here actions (in the domain of neighbourhoods, partners, jobs, and hospital visits). And  this feelings-to-actions relationship takes a generic form, is consistently replicable, and is fairly close to linear in structure. Therefore, it seems that human beings can successfully operationalize an integer scale for feelings even though there is no true scale. How individuals are able to achieve this is not currently known. The implied scientific puzzle—an inherently cross-disciplinary one—demands attention.

The  transformation from emotions to feelings involves a complex interplay between the brain’s limbic system, responsible for emotion generation, and the neocortex. The process is bidirectional; not only do emotions lead to feelings, but our thoughts and feelings can also influence our emotional state . For instance, merely thinking about a sad event can evoke the emotional state of sadness, demonstrating the power of cognitive processes in emotional regulation.

Given their subjective nature, feelings pose a challenge to measure. Unlike emotions, which can be quantified through physiological responses, feelings are often assessed through self-report measures, such as interviews, surveys, and questionnaires. Tools like the Self-Assessment Manikin (SAM) provide a non-verbal pictorial assessment technique that measures the pleasure, arousal, and dominance dimensions of feelings in response to stimuli . These self-report methods rely on individuals’ introspection and ability to articulate their feelings, highlighting the introspective and complex nature of feelings as opposed to the observable nature of emotions (2).

Emotions are associated with physiological responses that can be objectively measured, such as changes in heart rate, skin conductance, or brain activity. These physical reactions are innate and serve as the body’s way of preparing for a response to various stimuli (3).

Feelings, on the other hand, are psychological experiences. They are the conscious awareness and interpretation of emotions, often complex and multifaceted, reflecting the individual’s personal narrative. Because feelings are subjective, they are typically measured through self-report methods, such as surveys or interviews, which rely on personal introspection and articulation.

Another difference is the duration and intensity of emotions compared to feelings. Emotions are intense but brief, lasting for seconds to minutes, and are immediately triggered by specific events or stimuli . They are powerful but fleeting, reflecting the body’s immediate reaction to its environment.

Feelings, conversely, develop over a longer period and can last for hours, days, or even longer. They are less intense but more enduring, as they incorporate the emotion’s initial impact along with cognitive appraisal, making them more nuanced and reflective of the individual’s ongoing mental state.

How emotions are measured: They are measured in an objective way. 

Objective methods for researching emotions primarily focus on the physiological aspects, offering quantifiable data on the body’s response to emotional stimuli. These methods include:

• Electroencephalography (EEG): EEG measures electrical activity in the brain and is used to observe the neural underpinnings of emotional responses. It is particularly effective in studying the speed and patterns of brain activity associated with different emotions.
• Functional Magnetic Resonance Imaging (fMRI): fMRI provides insights into the areas of the brain activated by emotional stimuli, highlighting the neural circuits involved in emotional processing . This technique is invaluable for mapping the brain regions responsible for emotions and understanding their interconnections.
• Electrocardiography (ECG) and Skin Conductance: These methods measure the heart rate and skin conductance level changes associated with emotional arousal, offering direct indicators of the physiological impact of emotions . They are widely used in studies aiming to quantify the intensity of emotional responses.

Feelings are measured in a subjective way. 

• Surveys and Questionnaires: Standardized instruments such as the Positive and Negative Affect Schedule (PANAS) enable researchers to assess the subjective experience of emotions and feelings over time. Such tools are essential for correlating physiological measures with personal experiences of emotion.
• Self-Assessment Manikin (SAM): SAM is a non-verbal pictorial assessment tool that measures emotional reactions to stimuli in terms of pleasure, arousal, and dominance . It provides a visual scale for respondents, making it accessible for diverse populations, including those with verbal or cognitive limitations.
• Experience Sampling Methods (ESM): ESM involves asking participants to report their feelings and emotions at random intervals over time, offering insights into the dynamic nature of emotional experiences in real-life contexts . This method captures the fluctuating nature of feelings and emotions as they occur naturally.

In addition to the methodologies previously mentioned for objectively measuring emotions, Facial Expression Analysis stands out as a significant tool in understanding emotional responses. This method leverages advancements in technology to analyze the minute movements of facial muscles, correlating them with a range of emotions. Innovations in machine learning and computer vision have led to the development of sophisticated systems capable of accurately identifying and quantifying emotional expressions.

While these methodologies provide powerful tools for researching emotions and feelings, they also present challenges, particularly in ensuring accuracy and reliability in measuring subjective experiences. Additionally, ethical considerations must be addressed, especially in studies that might induce emotional distress in participants.

Studies also should delve deeper into the cultural dimensions of emotions and feelings. While emotions are often considered universal, the ways in which they are experienced, expressed, and interpreted can vary significantly across different cultural contexts (8). Research exploring these variations can provide valuable insights into the socio-cultural factors that shape emotional experiences, contributing to more culturally sensitive approaches in psychology, marketing, and international relations.

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And it is generally acknowledged that hormones are implicated in socioemotional behaviour. Emotion regulation on levels of hormones (i.e., testosterone, cortisol, oxytocin, estradiol, estrogen, progesterone, and vasopressin) are also being studied (9). Can we say how people express their emotions by just measuring their hormonal levels? Difficult because we can say they are responsible for certain emotions. But the biochemical reaction and interaction scenario  in a human body is highly complex. By just measuring one or two  hormones, it is difficult to  predict what interactions in a body are causing what effects.

But it is generally acknowledged that human socioemotional behaviours (e.g., attention, motivation, and trust) are influenced by a number of hormones.  There is considerable evidence from both non-human and human studies that endogenous hormone levels are associated with socioemotional behaviors, and that exogenous manipulation of hormone levels (i.e., drug administration to increase hormone levels or to block the effect of hormones) may lead to behavioural changes in humans such as changes in stress responses, aggressive behavior, and decision making. For example, research indicates that administration of testosterone leads to increased vigilance and motivation to act, while administration of oxytocin promotes search for proximity to others . As such, the existing evidence provides support for the notion that acute changes in hormone levels affect subsequent behaviour. Furthermore, the association between behaviour and hormones appears to be bidirectional as behavioural changes may also affect subsequent hormone levels, with several studies demonstrating that psychological states (e.g., feeling powerful, feeling stressed) and physical behaviours (e.g., aggressive behaviour) alter hormone levels in humans.

Yes, scientists are trying and experimenting with these methods to measure thoughts and emotions. Only time will tell how much they succeed in these difficult to analyse situations of brain and hormonal activity, their actions and interactions. 

Footnotes:

1. https://www.pnas.org/doi/full/10.1073/pnas.2210412119

2. https://imotions.com/blog/learning/best-practice/difference-feeling...

3. Critchley, H. D. (2005). Neural mechanisms of autonomic, affective, and cognitive integration. Journal of Comparative Neurology, 493(1), 154-166 ↩

4. https://www.sciencedaily.com/releases/2019/03/190325110227.htm

5. https://www.theguardian.com/science/2019/jul/30/neuroscientists-dec...

6. https://www.vox.com/future-perfect/2023/12/15/24001424/consciousnes...

7. https://www.discovermagazine.com/mind/how-do-scientists-measure-bra...

8. Matsumoto, D., & Hwang, H. S. (2012). Culture and emotion: The integration of biological and cultural contributions. Journal of Cross-Cultural Psychology, 43(1), 91-118

9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9216322/