Stimulating the Human Olfactory Bulb to Evoke Smell Perception: A Case Report from Awake Brain Surgery

Introduction: Approximately one-third of patients with olfactory dysfunction would consider the option of an olfactory implant, a device that would sample odorants and translate this information into an electrical stimulation of the brain to produce an olfactory percept. However, the brain location for placement of such a device is to date still debated. Case Presentation: We describe the single-case of a patient with left-sided frontotemporal astrocytoma who reported perceiving a lemon smell after electrical stimulation in the olfactory bulb. Conclusion: The awake-brain surgery provides a unique opportunity to test how smell percepts are formed at the central level in humans. This information is critical in the emerging field of olfactory implants. The present case emphasizes the significant role of the olfactory bulb as a target structure for the placement of an olfactory prosthesis.