The Brain Speaks the Mind

Five years have passed since the launch of the BRAIN Initiative by the Obama administration in 2013, which was followed by similar national projects in the EU and Japan aimed at elucidating the brain. Fundamentally, the brain contains 100 billion nerve cells that form their own networks, enabling it to remember and think. While active research has long been conducted to understand these brain functions, much remains unknown. Even today, research continues from various perspectives, including medical sciences, engineering, physical sciences, and psychology. Furthermore, research is being conducted using various approaches and familiar tools like MRI, EEG (electroencephalography), MEG (magnetoencephalography), and cerebral blood flow to try to understand it.

In our laboratory, we also use these devices selectively depending on the research subject. For example, in disease investigation, we use MRI because it is necessary to examine the inside of the brain in detail (this level of detail is referred to as high spatial resolution). Conversely, when we want to detect fluctuations in things like emotion, we use EEG, as it requires real-time measurement and analysis (observing time in fine detail is referred to as high temporal resolution). Thus, the equipment used varies greatly depending on the nature of the research.

I will now introduce the Kansei evaluation device we created using these technologies. We are conducting research to capture "Kansei"—the output, or feeling, in response to information input from a person's sensory organs—using EEG, which has the fastest response time. To capture how someone feels, we must first analyze the characteristics of the brainwaves that appear when an emotion is felt. In other words, we collect brainwave data for various feelings—such as irritation, fondness, heat, or deliciousness—and analyze them. If the amount of data used for this analysis is small, the resulting brainwave characteristics for each emotion may work for Person A but not for Person B, leading to a system that lacks versatility. Therefore, I performed a characteristic analysis based on data from approximately 10,000 people collected over 15 years. In other words, by collecting brainwaves from 10,000 people experiencing various emotions like stress and identifying their characteristics, we can then measure the intensity of stress by observing the degree to which those characteristics are present. Although it took many years, collecting this vast amount of data has made it possible to perform highly accurate measurements.

Up to this point, the research has focused on humans, but we are also conducting animal experiments to study how to alter emotions. Humans have feelings (kanjo), but we cannot know what animals are feeling. There are devices like "Bowlingual" and "Meowlingual" that are marketed as being able to understand the feelings of dogs and cats, but whether they are accurate is unknown, as we are dealing with animals that cannot speak. Instead, we can understand their emotions (jodo). (I will omit the distinction between feelings [kanjo] and emotions [jodo] here.) We are currently investigating whether these emotions can be controlled by applying minute electrical stimulation to the brain. If we find that emotions in animals can be altered simply by applying a stimulation signal to the brain, it may also be possible in humans (this is called translational research).

Thus, we are researching the elucidation of feelings through EEG and whether external stimulation to the brain can alter emotions in animals. These topics represent only a portion of the research conducted in our laboratory, but they are part of the broader effort to understand the brain. We are also focusing on other areas, such as brain analysis for converting thoughts into text.