The use of Biofeedback in Clinical Virtual Reality: The INTREPID Project

The applied technology for neuropsychology Lab develops innovative tools, applications, and services for psychology and neuroscience, exploring the opportunities offered by information and telecommunication technologies for clinical applications. The intrepid multisensory system has been developed for patients affected by generalized anxiety disorder. The innovation of the interpret project is the combination of virtual reality and biofeedback.

The patient is made aware of her reactions assessed using physiological parameters through the modification of the virtual reality environment in real time. The use of portable devices such as PDAs or smartphones allows the patient to perform at home. The same exercises learned in the therapist's office.

Virtual reality is used to enhance emotional processes of daily life by helping patients to face memories and situations associated with them. Each session performed with the therapist except the first one starts with a briefing about the course of symptoms the patient experienced at home during her everyday life and the possible difficulties encountered using mobile devices and running the home care scenario. After this step, the patient begins the virtual reality treatment.

First of all, she's connected with all the technological devices, including an head-mounted display, a joystick and biosensors that record her heart rates and skin conductance. At this point, the therapist turns on the biofeedback device and records the patient's physiological parameters for three minutes while the patient is in the rest condition. This serves as a baseline in order to compare the patient's activation during pre and post sessions.

After that, the patient can start exploring the virtual environment. The head mount and display helps her to feel part of the environment and thus enhances her sense of presence. That is the feeling of being inside the simulated experience, turning her head around.

The patient can have a look at the virtual environment while the images change coherently with her head movement up, down, right, left. The J pad is used to walk forward and backward. The virtual environment represents a tropical island rich in vegetation and surrounded by the ocean.

Following the audio narrative, the patient can explore the island starting from the beach, which is the arrival point reached by boat, following a foot foot path that guides her through the forest. She arrives at the starting point where different signs indicate the directions to the different target areas. Each of these areas includes a relaxing exercise during the training, following indications given by the voice guide, the patient tries to relax while her physiological parameters modify some elements of the virtual environment.

In real time in the island, there are four targets, areas, waves, fire, waterfall, and gazebo. The choice of the target area depends on the session the patient is attending. Session one and two are dedicated to the campfire exercise in which the narrative induces relaxation of arms and legs.

Physiological parameters control the fire intensity so that the reduction of activation results in reduction of the fire intensity until it goes out. In sessions three and four, the patient performs the exercise related to waves and learns how to relax the head and the trunk. In sessions five and six, she reaches the waterfall area and following the narrative tries to relax the whole body at the same time.

In this area, the reduction of the physiological arousal corresponds to a reduction of the stream, intensity of the waterfall until the water stops. At the end of the sixth section, the patient has to find some words or images that evokes stressful situations in her real life. These items are used to customize the last two sessions, exercise performed in the gazebo area.

During this exercise, the patient visualizes the item chosen as if she undergoes a stress in of ation program, applying the learned relaxation techniques, the patient experiences a reduction in size, fading or floating of the chosen items depending on the settings of the customization. Once the clinical exercise has been completed, the therapeutic session goes to the conclusion before the patient is disconnected from all the devices and other physiological measurement in rest condition must be run In order to strengthen the acquired results and to gain even more abilities to relax outside the therapist's office, the treatment is repeated day by day using the home care scenario. It consists of the same virtual environment running on a very portable device, the HTC promo mobile phone without the head mounted display and the joystick at her own home.

The patient spends some time at least once a day, performing the exercise trained. During the previous session performed with the therapist, she connects herself with the biosensors, which are connected via Bluetooths to the phone and listens to the relaxing narrative. At this point, she launches the application on the HTC and starts the session.