Monash University human-computer interaction researchers have developed a playful water-inspired extended reality system using floatation tanks to help reduce aquaphobia.

The study, published as part of the Proceedings of the CHI Conference on Human Factors in Computing Systems this year, was led by researchers from the Faculty of Information Technology's Exertion Games Lab.

The research combined a water-based virtual reality (VR) landscape with the controlled environment of a water-filled floatation tank to help participants overcome the fear of water. The results showed participants experienced less anxiety regarding water while experiencing the extended reality system.

The experience involves floating in a tank while a VR headset delivers a virtual auditory and visual environment. The participant's heart rate (measured using a sensor), breathing (sensed via the headset's microphone), and slight head movements (sensed via the headset) control interactions within the virtual environment.

The lead author of the research paper, human-computer interaction researcher Ph.D. Candidate Maria Montoya, said people who fear being in water are often unable to enjoy recreational activities in water and can even develop a fear of drowning.

"We believe there is an opportunity for interactive systems to bring people closer to water in fun and accessible ways," Montoya said.

"Similar to virtual reality exposure therapy, which progressively engages people to face fearful situations, the extended reality (XR) system we developed offers rewards with playful experiences through an entertaining interactive story to encourage participants to be in the floatation tank for increasingly longer periods of time."

The XR experience provides an interactive journey where the participant is guided through three main virtual water worlds by a virtual character called a "water spirit." The water spirit is a guide that provides the participant with verbal assurances that they are doing fine and are safe and encourages them to enjoy the experience.

The "journey" in this VR experience is similar to exposure therapy's "step-by-step" progressive exposure of participants to a fearful situation.

In the third and final stage of the XR experience, the participant moves skyward, and the water spirit guides them to navigate through cyclones and encourages them to control their heart rate to stop the rain and storms.

The researchers enabled hands-free interactions by using the headset's sensors and microphone to encourage body relaxation suitable for people with a fear of being in the water. This helped the participants to not be concerned with performing any strenuous or complex movements while they were in water.

The study worked with twelve participants who had a self-reported fear of being in water. The procedure consisted of six steps including recording the baseline heart rate of the participants while they lay on a yoga mat before entering the water, floating in the tank without technology and then adding the XR experience with a headset while the participants were floating in the water.

Co-author of the research, Exertion Games Lab Director Professor Florian "Floyd' Mueller, said the study results confirmed that the XR system helped to reduce the participants' fear of being in water.

"Our heart rate variability index showed the participants tended to be less anxious while they were being entertained by the XR system compared to when they were floating in the tank without any technology," Professor Mueller said.

"We hope that our research and findings might help psychologists, mental health professionals, health care workers and other human-computer interaction researchers to explore extended reality as a viable means to develop interventions to manage aquaphobia and possibly other phobias."