Over the past century, public health interventions have nearly doubled the average lifespan. This welcome development has been compromised by commensurate rises in the incidence of cancer, Alzheimer’s and many other diseases of age. However, advances in genetic engineering, neurotechnology and drug development now look set to increase our “healthspan” too.
The 21st century has seen an acceleration in our ability to decode cognitive states from both invasive brain implants and, increasingly, non-invasive techniques. It is also becoming possible to manipulate those brain states in more targeted ways using a wide spectrum of methods, from electrical to chemical.
Human genome editing is a fast-growing field, poised to bring unprecedented disruption in medicine, as well as new possibilities for human enhancement. Today, most gene editing is not applied to living embryos or directly done on patients, but ex vivo as is practiced, for example, in cancer immunotherapy. But much of the work being done today is with a different vision: to deliver the genome editor into the patient’s body, where it will find the right cells and perform its task.
In the past few decades, research has begun to suggest that there is an underlying biology of ageing that drives the diseases of ageing. One consequence of this is that, rather than accept the ageing process as a natural consequence of life, an increasing body of research is beginning to treat it specifically as a risk factor for disease, and target it for treatment. Experiments have identified ways to delay, stop and even in some cases reverse the process. A range of interventions, from small-molecule drugs to stem cell injections, is now under investigation. The goal is to use these insights to develop an entirely new kind of public health programme based on radical health extension.
Even though there is no standard definition of consciousness, in the medical context, methods have had to be devised to verify its presence or absence, to define whether a patient is in a vegetative state, and whether they can be expected to return to normal conscious state. In this arena, the lack of agreement on what consciousness is does not prevent us adopting technologies and conceptual advances that help make decisions. As with many medical applications, these technologies will start in a clinical setting, but the insights they yield will eventually benefit the broader population.