Repair,Regeneration,and Replacement,Revisited (Redux)

Introduction: Human-Centered AI

On February 14, 2012, the University of Arizona’s Repair, Regeneration, and Replacement Revisited ¹ lecture envisioned a future where technological innovation could help delay the effects of aging and disease. ¹ Now, 13 years later, the global health landscape has undergone significant transformation, marked by advances in regenerative medicine, prosthetics, wearable health technologies, and data-driven personalized care.

Thirteen years after the forward-looking 2012 lecture, this editorial assesses progress across four key medical advancements. These four technologies share key commonalities in their integration with artificial intelligence (AI) and their potential to revolutionize health care and human enhancement, in the fields of regenerative medicine, human-machine interfaces, personalized health monitoring, and memory engineering merged with AI. We reflect on achievements and ongoing challenges, highlighting recent breakthroughs and future directions in these four technologies and offer a tour of Tomorrowland today. By emphasizing interdisciplinary collaboration and technological integration, we advocate for continued innovation to address the pressing burden applying medical advancements to aging populations and long-term disease.

The lecture highlighted humanity’s evolving relationship with death, divided into three ages: ²

• 1. Disaster (300 000 BCE—12 000 BCE): In early human history, external threats such as predation, environmental disasters, and violence were the primary causes of death.

• 2. Disease (12 000 BCE—2009 CE): As societies developed and populations grew, infectious diseases like the plague and smallpox emerged as dominant threats.

• 3. Decay (2009—the present): Today, long-term, degenerative conditions—such as cardiovascular disease, diabetes, and cancer—constitute the leading causes of death. The transition to this age was marked by the 2009 global crossover, where more people died from noncommunicable diseases than infectious ones.

Faced with this new reality, today we must ask: How should we delay decay? The lecture proposed three possible approaches: accepting decay as the natural order (too passive), disobeying decay by seeking to conquer it (too hubristic), or delaying decay through scientific, technological, and collaborative efforts. The third option, rooted in humility and grounded in interdisciplinary innovation, offers the most promising path forward.

As we revisit the ideas presented in 2012, we contend that four medical technologies, which share key commonalities in their integration with AI, offer the potential to revolutionize health care and human enhancement. These emerging technologies include (1) regenerative medicine, (2) human-machine interfaces, (3) personalized health monitoring, and (4) memory engineering merged with AI. These four key medical technologies have led to breakthroughs in multiple areas, including organ transplants, stem cell therapies, smart prosthetics, and health apps. While these breakthroughs will help people with many health conditions, diabetes, which affects more than 800 million adults, worldwide, is a disease where data support diagnosis and treatment. Diabetes stands to be a major beneficiary of these technological advances. ³

We foresee a convergence of these four emerging medical technologies with human-centered AI that (1) prioritizes the needs, values, and well-being of humans and (2) focuses on creating systems that are transparent, ethical, and aligned with human goals, by serving as a collaborative tool rather than as a replacement for human input. Human-centered design, supported by AI, applied to regenerative medicine, human-machine interfaces, personalized health monitoring, and memory engineering is poised to significantly advance the human condition in 2025 and beyond. Innovation in medical technology is emerging that will lead to empathy-driven solutions that prioritize user needs and experiences. Technology combined with human-centered design will solve challenges posed by long-term degenerative conditions (such as diabetes), enhance human capabilities, and improve quality of life.

Regrowth, Replacement, and Repair: Where Are We Now?

Four areas where regrowth, replacement, and repair are making strides include (1) transplants, (2) stem cells, (3) matrices/scaffolds, and (4) heart regeneration. These areas of tissue repair and regeneration of damaged tissue promise to eventually lead to artificial organs. ⁴

Transplants

While traditional organ transplants remain vital, xenotransplantation—using organs from genetically modified pigs—has emerged as a game-changer. In 2022, a successful pig heart transplant in a human patient demonstrated the potential for overcoming donor shortages.^5,6 Meanwhile, advancements in bioengineered organs, such as lab-grown kidneys, continue to push the boundaries of what is possible. ⁷

Stem Cells

The field of stem cell research has progressed dramatically, particularly with the development of induced pluripotent stem cells (iPSCs). Unlike embryonic stem cells, iPSCs avoid ethical concerns and can be reprogrammed from adult cells. Recent clinical trials have demonstrated their efficacy in repairing damaged heart tissue and regenerating cartilage.^8,9 Stem cells are being used for treating type 1 diabetes. ¹⁰

Moreover, the integration of CRISPR-based gene editing has enabled more precise control over stem cell differentiation.

Matrices and Scaffolds

Biodegradable scaffolds have evolved into multifunctional platforms that release growth factors, enhance cell adhesion, and integrate sensors to monitor tissue regeneration in real time. Innovations such as 3D-printed vascularized scaffolds have accelerated the creation of functional tissues for transplantation. Clinical trials involving wound healing matrices for diabetic foot ulcers have shown promising outcomes, supporting limb preservation efforts.^11-13

Heart Regeneration

The delivery of cardiac progenitor cells via bioengineered patches has improved outcomes in heart failure patients. The field is moving toward combining cell therapy with electrical stimulation and biomaterial support to enhance myocardial repair.

Hardware Upgrades (Human-Machine Interfaces): What has Changed in 13 Years?

Human-machine interfaces are being developed to bridge biological and artificial systems through sophisticated input/output mechanisms, adaptive control systems, and a focus on enhancing human capabilities. Six examples of these interfaces include (1) bipedalism/biomechanics, (2) advanced prosthetics, (3) wearable robotics, (4) brain-computer interfaces (BCIs), (5) memory engineering, and (6) artificial hearts.

Bipedalism and Biomechanics

Insights into human biomechanics continue to inform prosthetic design, with real-time gait analysis helping refine personalized solutions. Robotic systems now mimic natural limb movement with greater precision, reducing the energy expenditure associated with prosthetic use.

Advancements in biomechanics have led to the design of innovative footwear that enhances mobility and prevents falls by improving gait and balance.^14-16 In addition, such footwear redistributes pressure on the feet, reducing the risk of foot ulcers in individuals with diabetes. These advancements showcase how interdisciplinary collaborations between medicine, engineering, and design can lead to practical solutions that address the challenges posed by long-term, degenerative conditions.^17,18

Advanced Prosthetics

Hugh Herr’s work in powered prosthetics has advanced with the development of biohybrid limbs that integrate living tissue and electronic components. Recent innovations include prosthetic devices that restore a sense of touch by relaying sensory feedback directly to the brain. ¹⁹

Wearable Robotics

Exoskeletons are no longer limited to research labs; they are being commercially deployed to assist individuals with mobility impairments and spinal cord injuries. In 2024, Food and Drug Administration (FDA)-approved exoskeletons became widely available in rehabilitation centers, showing significant improvements in walking speed and muscle activation. Artificial muscles constructed from shape-memory alloys now offer lightweight, responsive alternatives to traditional pneumatic systems.^20,21

Brain-Computer Interfaces

Breakthroughs in neural interface technology have enabled quadriplegic patients to control prosthetic limbs and computers using thought alone. Companies such as Neuralink and Blackrock Neurotech are pioneering minimally invasive brain implants, with recent trials demonstrating improved motor function and communication. ²² Brain areas outside the motor cortex have been demonstrated to be very promising, especially “cognitive” and “integration” areas, demonstrated first in humans in 2015. ²³ These areas have recently been shown to be useful in “silent speech” decoding in 2024. ²⁴ Somatosensation is known to be critical, perhaps as important as motor function, in making effective BCI’s. The first “naturalistic” artificial sensation in a human was by intracortical microstimulation and was reported in 2018. ²⁵

Noninvasive approaches to BCI’s will greatly expand the possibilities, with functional ultrasound being the most promising approach, as recently reported in a nonhuman primate model in 2023 ²⁶ and in humans in 2024. ²⁷

With these advances, one can imagine a human-based avatar—one we could control at a distance. ¹ This has been accomplished in a number of ways. Most notably, the multi-institutional “Braingate” collaboration described piloting a drone using a BCI. ²⁸

Memory Engineering

The concept of memory engineering, initially discussed as speculative, has gained traction with advances in AI-driven memory augmentation. Digital life-logging devices now allow individuals to record daily events continuously, creating a “superhighway of information” rather than the fragmented recall of memory. This technology raises both exciting possibilities and ethical concerns, as enhanced recall may alter our understanding of personal identity and experience. ²⁹ Recent research explores applications in neurorehabilitation for Alzheimer’s and dementia, offering hope for improving memory retention and cognitive function. ³⁰ Indeed, the Ray Ban Meta glasses, released last year, allow for basic interaction with the community in real-time. While this was pioneered 12 years ago using Google Glass, ³¹ the form factor has become more socially acceptable, latency continues to reduce, and battery life continues to improve.

Artificial Hearts

The total artificial heart has seen miniaturization and efficiency improvements, with devices like SynCardia now offering portable options.^32,33 Researchers are developing next-gen systems using biocompatible materials and wireless power transfer to reduce complications.

Optional Extras and Apps: The Personalized Health Revolution

The personalized health revolution paradigm combines elements of four themes that support the use of wearable devices to allow continuous monitoring of physiologic processes. These themes include (1) the quantified self-movement to promote multimodal monitoring to support precision medicine health care, (2) smart fabrics and medical tattoos to capture physiologic data in new ways, (3) telemedicine and home monitoring to facilitate two-way communication between patients and clinicians, and (4) data privacy and ethics to provide assurance that data collected in new ways and transmitted wirelessly to the cloud in the form of protected health information will remain private. ³⁴

Quantified Self Movement

The wearables market has expanded dramatically since 2012, with continuous glucose monitors (CGMs), smartwatches, and fitness trackers offering real-time insights into metabolic health, cardiac function, and sleep quality. Companies like Dexcom and Apple have led the charge in integrating these technologies into everyday life.^35-37

Smart Fabrics and Medical Tattoos

Smart fabrics embedded with sensors can now monitor muscle activity, hydration levels, and temperature. Stretchable medical tattoos, capable of tracking vital signs, represent the next step in discreet health monitoring. Advances in flexible electronics and wireless charging have made these technologies more practical for daily use.^38,39

Telemedicine and Home Monitoring

The COVID-19 pandemic accelerated the adoption of telehealth, making virtual consultations and remote monitoring commonplace. Digital health platforms now integrate predictive analytics, allowing for early detection of conditions like atrial fibrillation and diabetic complications.^40,41

Data Privacy and Ethics

As more health data are collected, ethical concerns around privacy and security have intensified. Regulatory frameworks such as the General Data Protection Regulation (GDPR) and the Health Insurance Portability and Accountability Act (HIPAA) have guided the responsible use of patient data, but continued vigilance is required. Blockchain-based systems are being explored to give patients greater control over their medical information. ⁴² Mentioning many of the social contract theorists like Hobbes, Locke, and Rousseau, the last lecture called for a “social cyber contract.”^1,43 That contract or concorde is clearly still under development.

Memory Engineering Merged With AI

Boundaries between human and nonhuman are becoming increasingly blurred, because of AI systems capable of socializing and expressing emotions. Two examples of memory engineering involve (1) enhanced computing performance and (2) a convergence of technology and humanity.

Enhanced Computing Performance

Artificial Intelligence systems with robust memory capabilities can efficiently analyze vast amounts of medical records and data from wearable devices to develop personalized treatment plans and assist clinicians in making informed decisions. Multiple simultaneously collected data streams can now be processed in real time to provide useful information to support a precision medicine paradigm. ⁴⁴

The Convergence of Technology and Humanity: Present and Future

As we advance technologically, the question of what constitutes our identity becomes central. Are we simply the sum of our memories, or is there a deeper essence that defines us? The integration of memory augmentation and brain-computer interfaces challenges traditional views of selfhood. The ability to implant and retrieve memories raises profound questions about authenticity and human experience. If our memories are no longer summarized but stored in exhaustive detail, how might this impact our emotional resilience, decision-making, or sense of self-worth? The original lecture imagined a time when one would not be “strolling down memory lane” but rather being hit with a “superhighway of memories.” If we are the sum of our memories, what if they were never summarized? Learning how to “forget” may be just as important as learning what to remember. ¹

Steve Jobs’ vision of the intersection between technology and the liberal arts remains relevant today. Emerging technologies, such as augmented reality, brain-computer interfaces, and digital twins, exemplify this fusion. By fostering collaboration between engineers, clinicians, ethicists, and policymakers, we can create innovations that are both technically sound and ethically grounded.

Conclusion: A Renewed Call for Collaborative Progress

Thirteen years after the initial lecture, the vision of delaying decay through technological innovation is more attainable than ever. From regenerative medicine breakthroughs to personalized health monitoring, the future of health care for diabetes and other diseases lies in our ability to combine cutting-edge technology with empathy and ethical responsibility.

Looking ahead, the challenge will be to ensure equitable access to these innovations, particularly in underserved communities. As we continue to build on the foundation laid in 2012, we must remain committed to interdisciplinary collaboration and patient-centered care. By doing so, we can address the global burden of aging and long-term disease while improving the quality of life for future generations.