Although the sense of smell is often taken for granted, approximately 20% of the population experiences some degree of olfactory dysfunction, ranging from partial impairment (hyposmia) to complete loss (anosmia). These individuals find that their olfactory dysfunction not only handicaps them in their daily life, but also affects their physical and psychological health. Various paradigms exist for restoring the sense of smell, but these methods are not effective for all patients, leaving many to suffer a degraded quality of life. These patients are seeking solutions, including prosthetic technology. While implants and prostheses already exist for other sensory modality such as hearing, developing an olfactory prosthesis technology is more complex, as it must overcome the dual obstacles of the detection of odorous molecules and neural stimulation.
This book provides a comprehensive overview of the state-of-the art. Tackling existing challenges through an interdisciplinary approach, Olfactory Prosthesis: From Concept Towards Reality brings together researchers in nanotechnology to develop appropriate olfactory sensors, in microtechnology, medicine and neuroscience to develop neural stimulators capable of targeting the olfactory system, in biotechnology and machine learning to combine sensor and stimulator technologies, and in mechanical design and cognitive sciences to make these integrated devices usable in real life. Finally, the book presents an initial proof of concept for an olfactory substitution prosthesis.
The olfactory system.
Chapter 1: Neurobiology of the human sense of
smell.
Chapter 2: Human olfactory perception.
Chapter 3: Inter-individual
variability in human olfaction.- Olfactory deficits.
Chapter 4: Olfactory
deficits: causes, types and prevalence.
Chapter 5: Diagnosis of olfactory
deficits.
Chapter 6: Effects of olfactory deficits on quality of life and
needs of patients.- Therapies to cure olfactory deficits.
Chapter 7:
Existing therapies in olfactory deficits.
Chapter 8: Olfactory training.-
Chapter 9: Possible future technologies.- Olfactory sensor technologies.-
Chapter 10: Electronic noses.
Chapter 11: Biomimetic sensors (optical
sensors).
Chapter 12: Miniaturizable sensors (cMUT).- Olfactory stimulation
technologies.
Chapter 13: Stimulation electrode devices.
Chapter 14:
Electrical stimulation in the brain.
Chapter 15: Electrical stimulation in
the nasal cavity.- Substitution of olfaction with other senses.
Chapter 16:
Which senses can substitute olfaction?.
Chapter 17: The trigeminal system as
a substitution system.
Chapter 18: Designing a substitution system.- A proof
of concept to substitute olfaction and future directions.
Chapter 19:
Acceptability of a substitution device.
Chapter 20: A proof of concept to
substitute olfaction via the trigeminal system.
Chapter 21: Future
directions.
Moustafa Bensafi is a CNRS Research Director at the Lyon Neuroscience Research Center, where he leads pioneering research on the psychology and neurobiology of olfaction. His research bridges neuroscience, cognitive sciences, and clinical applications, addressing a critical gap in understanding how the brain interprets smells and their emotional significance. He earned his PhD on the affective processing of odors under the supervision of André Holley and Catherine Rouby, and further expanded his expertise during a post-doctorate at the University of California at Berkeley, before joining the CNRS in 2004. In 2008, Moustafa Bensafi was awarded the CNRS Bronze Medal, recognizing his outstanding early-career contributions to neuroscience. He is the author of over 150 scientific publications and the book "Brain and Smell". From 2021 to 2025, he coordinated the European ROSE project, a multidisciplinary effort to develop the first proof of concept for an olfactory prosthesis. He is a leading figure in olfactory cognition research, with a career marked by innovation, leadership, and a commitment to both scientific discovery and societal impact.
