From Sword Art Online to Reality: BCI-Based Virtual Embodiment with Taiga Seri

Can we control a virtual body as naturally as our own—using only brain activity?

This question, inspired by the iconic series Sword Art Online, was set by Taiga Seri, a PhD researcher at Keio University. Answering this question led Taiga to the nomination for the International BCI Award, bringing all of us one step closer to a future once imagined in science fiction.

🧭 From Sci-Fi Inspiration to Scientific Direction

Taiga shares how a middle school encounter with immersive virtual reality concepts sparked his long-term vision: eliminating physical boundaries and enabling humans to interact, move, and connect in fully immersive digital worlds.

🧠 Building Intuitive Avatar Control

At the core of his research is a non-invasive, multimodal brain-computer interface that combines:

• EEG signals (including ERD and PMBR for movement and stopping)
• Eye-tracking data
• Real-time scene understanding (semantic segmentation)

This system allows users to:

• Walk using imagined movement
• Stop intentionally using brain signals
• Navigate environments through natural, unconscious gaze patterns

The goal is true embodiment, where users feel the avatar is their own body.

🧗 Challenges: From Concept to Reality

Taiga discusses key challenges, including:

• Achieving intuitive (not forced) control
• Measuring something as subjective as agency and ownership
• Integrating neuroscience with machine learning and computer vision
• Bridging the gap between current BCI performance and seamless real-world usability

🔬 A Breakthrough in Measuring "Agency"

One of the most innovative aspects of his work is the use of auditory event-related potentials (ERP) as a neural biomarker of agency.

His findings suggest:

• Higher control success → stronger sense of agency
• Intentional stopping increases agency beyond standard controls
• Brain-based control can, in some cases, rival traditional gaming interfaces

This opens new possibilities for objectively measuring embodiment in neurotechnology systems.

🚀 Applications & Future Directions

Taiga envisions applications across:

• Neurorehabilitation (e.g., stroke recovery)
• Gaming and immersive environments
• Remote human interaction without physical constraints

His long-term goal: 👉 A world where distance no longer limits human connection—where people can meet, interact, and experience reality together in shared virtual spaces.

💡 Career Insights for Aspiring Neurotech Innovators

Taiga shares valuable advice:

• Start with a clear vision—even if inspired by fiction
• Seek environments where you can build independently
• Combine disciplines (neuroscience + AI + engineering)
• Find your unique angle—something no one else is doing

🌱 Closing Reflection

This episode is a powerful reminder that today's neurotechnology breakthroughs often begin as yesterday's imagination.

As Taiga puts it: "Dream first. That dream will guide your science."

Chapters

00:00:02 - Brain-Controlled Avatars: The Future of BCI

00:03:22 - Bioinformatics and Neuro-Rehabilitation Research

00:08:58 - Diving into Virtual Worlds Without Moving

00:14:37 - Removing Spatial Limitations Through Immersive Technology

00:18:14 - Vision Shapes Your Path and Opportunities

00:24:55 - Multimodal Recording Opportunities in Neuroscience

00:31:03 - Stroke Rehabilitation Using Brain-Computer Interfaces

00:34:35 - Post-Movement Beta Rebound and EEG Activity

00:39:00 - ERD, PMBR, and Event-Related Synchronization Explained

00:41:03 - Embodiment: Ownership vs Agency in BCI

00:44:52 - Ownership vs Agency in Virtual Avatars

00:51:07 - Auditory ERP Measures Agency in Virtual Environments

00:58:15 - Unconscious Eye Movement for Direction Control

01:03:19 - Eye Gaze Tracking at Intersections vs Straight Roads

01:07:47 - Finding Neural Markers of Embodiment and Agency

01:14:41 - Investigating Embodiment Through Peripersonal Space

01:18:23 - Tips for Award Submissions and Finding Your Uniqueness

01:23:15 - Pursuing International Research Experience During PhD

01:26:09 - Dream Big to Fuel Your Future Success

The International BCI Award series is sponsored and organized by g.tec medical engineering. Submit your work for the BCI Award today! https://www.bci-award.com/Home (the submission deadline is September 1st).

About the Podcast Guest

Academic Title and Affiliation: Taiga Seri is a Doctoral Research Fellow supported by the Japan Society for the Promotion of Science (JSPS DC1 Research Fellowship). He is based in Japan and conducts his research at Keio University, within the Graduate School of Science and Technology, Department of Biosciences and Informatics, under the supervision of Professor Junichi Ushiba.

Research Interests and Goals: Taiga's work centers on the concept of embodiment—exploring how virtual avatars can be experienced not simply as external tools, but as true extensions of the self.

In his research, he combines multimodal brain-computer interfaces (BCIs) with innovative approaches such as auditory event-related potentials (ERPs) to both induce and measure this sense of embodiment.

Looking ahead, Taiga aims to translate these advances into clinical applications, particularly to support individuals with physical impairments in regaining activities of daily living.

As part of this vision, he plans to pursue postdoctoral research in laboratories specializing in invasive BCIs, expanding his expertise and challenging himself in new research environments beyond his current institution and country.

About the Podcast Host

The Neurocareers podcast is brought to you by The Institute of Neuroapproaches (https://www.neuroapproaches.org/) and its founder, Milena Korostenskaja, Ph.D. (Dr. K), a career coach for people in neuroscience and neurotechnologies. As a professional coach with a background in neurotech and Brain-Computer Interfaces, Dr. K understands the unique challenges and opportunities job applicants face in this field and can provide personalized coaching and support to help you succeed.

Here's what you'll get with one-on-one coaching sessions from Dr. K:

• Identification and pursuit of career goals
• Guidance on job search strategies, resume, and cover letter development
• Neurotech / neuroscience job interview preparation and practice
• Networking strategies to connect with professionals in the field of neuroscience and neurotechnologies
• Ongoing support and guidance to help you stay on track and achieve your goals

You can always schedule a neurocareer consultation/coaching session with Dr. K at https://neuroapproaches.as.me/neurocareer-consultation

Subscribe to our Nerocareers Newsletter to stay on top of all our cool neurocareers news at updates https://www.neuroapproaches.org/neurocareers-news