Elevating Virtual Reality Experiences with Olfactory Integration: A Preliminary Review

Meryck Felipe Brito da Silva; Igor Henrique Sanches; Joyce Villa Verde Bastos Borba; Ana Carolina de Amorim Barros; Francisco Lucas Feitosa; Rodrigo Mendes de Carvalho; Arlindo Rodrigues Galvão Filho; Carolina Horta Andrade

doi:10.5753/jbcs.2024.4632

Authors

Meryck Felipe Brito da Silva Advanced Knowledge Center for Immersive Technologies https://orcid.org/0000-0003-4969-3015
Igor Henrique Sanches Advanced Knowlegde Center for Immersive Technologies https://orcid.org/0000-0002-8772-2801
Joyce Villa Verde Bastos Borba Advanced Knowlegde Center for Immersive Technologies https://orcid.org/0000-0002-2663-5173
Ana Carolina de Amorim Barros Advanced Knowlegde Center for Immersive Technologies https://orcid.org/0009-0008-7736-129X
Francisco Lucas Feitosa Advanced Knowlegde Center for Immersive Technologies https://orcid.org/0009-0006-0619-4514
Rodrigo Mendes de Carvalho Advanced Knowlegde Center for Immersive Technologies https://orcid.org/0009-0008-5187-0395
Arlindo Rodrigues Galvão Filho Advanced Knowledge Center for Immersive Technologies https://orcid.org/0000-0003-2151-8039
Carolina Horta Andrade Advanced Knowlegde Center for Immersive Technologies https://orcid.org/0000-0003-0101-1492

DOI:

https://doi.org/10.5753/jbcs.2024.4632

Keywords:

Virtual Reality, Artificial Intelligence, Olfactory, Brain–Computer Interface, Olfactory Virtual Realism

Abstract

Virtual reality (VR) provides immersive audio-visual experiences but often overlook olfactory senses, which are crucial for human perception and cognition. Smell enhances object recognition, visual spatial attention, and evaluation methods for spatial attention deficits. The sense of smell relies on the olfactory nerve to create a direct link between external stimuli and the limbic system, a brain network involved in regulating emotions such as sadness, anger, joy, and fear, as well as controlling physiological responses like the startle reflex, vocal intonation, pain perception, and memory processes. Artificial intelligence (AI) is essential for integrating odors into VR, enhancing contextual understanding and synchronizing smells with plot developments. Current multi-modal approaches highlight the need for integrated models combining images, texts, and smells. Olfactory cues can enhance memory retention and recall, benefiting educational and training applications. Incorporating scents into immersive technologies creates more realistic and engaging experiences, crucial for fields like healthcare, military training, and education. In this preliminary review, we will explore Olfactory Virtual Reality (OVR) technologies, AI applications, available devices, and future perspectives in the field. Additionally, we will discuss the challenges facing this technology, including issues of delay, size, and the limited range of available odors. A new wearable interface featuring miniaturized odor generators (OGs) and AI algorithms enables rapid responses and low power consumption, achieving latency-free mixed reality. OVR research shows promising applications in treating Post-Traumatic Stress Disorder (PTSD), alleviating anxiety, and enhancing immersion. Recent advancements, such as compact OGs and computer-controlled olfactory stimulation, represent significant progress in multisensory communication technology.

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