Simulating Hallucinations in Virtual Reality

By Roland Piquepaille

When psychiatrists are facing mentally disturbed people, they often find difficult to understand their patients' hallucinations. This is why a multidisciplinary team of the University of Queensland in Australia has written a special software to help them and their patients. In "VR tool re-creates hallucinations," Technology Research News says that the hallucination simulation software is a three-dimensional environment, something like the game Quake. This prototype system runs on a "large virtual reality system that includes three projectors and a 9-meters-wide by and 2.5-meters-high screen curved to provide a 150-degree field of view." The researchers are now porting this software on PC platforms in order to be used in individual clinicians' offices. Commercial applications should be ready within five years.

Researchers [at the Advanced Computational Modelling Centre (ACMC)] from the University of Queensland in Australia have written software designed to allow psychiatrists to gain an understanding of the reality of patient hallucinations. "The idea is to get [medical students] to understand what it is like from the patient's point of view," said Geoffery Ericksson, the research fellow at the University of Queensland.

The hallucination simulation software is a three-dimensional environment something like the game Quake, said Ericsson. The researchers interviewed a patient to get descriptions of a set of real-life hallucinations, then depicted them in the software.

How did these researchers design the system?

The researchers used photographs of room layouts and equipment from a local psychiatric unit to build the virtual reality model. They also used photographs to generate textures of wall and floor coverings. The prototype software runs on a university virtual reality system that includes three projectors and a 9-meters-wide by and 2.5-meters-high screen curved to provide a 150-degree field of view.

[Note: Here is a rendering of the VR environment at the VISAC (Visualisation and Advanced Computing) Laboratory.]

The user is able to navigate around the environment using a mouse and keyboard, and can trigger hallucinations via hotkeys or clicking. Hallucinations also automatically occur when the user gets near certain objects.

Visual hallucinations include an abyss appearing where the floor should be, random flashes of light, the user's image in a mirror getting thinner and bleeding from the eyes, and an initially comforting but increasingly abusive Virgin Mary.

Below are examples of what you could see in this environment. All the images below belong to the creators of the project, "A Virtual Environment to Simulate the Experience of Psychosis" (Credit: Jasmine Banks and her colleagues, University of Queensland).

    

These two images from a comforting and an abusive Virgin Mary were the most challenging hallucinations in this psychosis simulation. In the process, the Virgin Mary can say such things as "you're worthless" and "go and kill yourself."

    

And in this prototype development of a living room model, you can see a wall painting of Montmartre before and after morphing (or in this case suffering from hallucinations).

What will be the next steps?

The researchers' next step is to increase their library of hallucinations by interviewing more patients. Eventually the software will have enough fodder that clinicians will be able to re-create the hallucinations of a particular patient by simply piecing together existing hallucinations from the library, said Ericsson. The researchers are also looking to begin critical trials to test the software's utility in cognitive behavioral therapy.

The software will be used this year as a part of teaching courses, said Ericsson. If subsequent studies show that virtual reality is helpful in cognitive behavioral therapy, a commercial tool could be ready within five years, and widely available in 20 years, said Ericsson.

For more information, you can read the research paper published by the Journal of Network and Computer Applications in its January 2004 issue under the name "Constructing the hallucinations of psychosis in Virtual Reality." From the archives, you have access to the full text of the paper. Alternatively, here is a direct link, but the URL is so long that it might easily disappear.

Sources: Technology Research News June 14, 2004; University of Queensland; Journal of Network and Computer Applications, Volume 27, Issue 1, January 2004