Effectiveness of a Projection-based Augmented Reality Exposure System in Treating Cockroach Phobia.

The measurement of attentional biases as a clinical evaluation tool in anxiety disorders is presented as a valuable instrument capable of evaluating changes in the automatic cognitive processes that are involved in their maintenance. However, the variability between the different methodologies used for its measurement has produced a lack of empirical consistency that supports the use of this tool with a clinical purpose. The appearance and implementation of eye tracking technology in experimental studies has made it possible to overcome this problem. Despite this, to our knowledge, there are still no studies that implement this technology in the clinical field as a tool for evaluating therapeutic effectiveness.

Specific phobia is the anxiety disorder with the highest prevalence and, specifically the animal subtype, is one of the most prevalent (3.8%), producing a significant interference and high comorbidity. Despite that in vivo exposure therapy is the treatment of choice for specific phobia, the high dropout rates and difficulties in its application pose major limitations for its therapeutic implementation. The emergence of technologies such as augmented reality (AR) has made it possible to overcome these barriers, offering new ways of applying exposure therapy. AR technology offers the capacity to interact with the stimulus in the real world, facilitating the therapeutic process and the generalization of its results. Some studies have tested the effectivity and efficacy of the AR technology in small animals exposure treatment revealing promising results. However, these studies used a version of AR that requires the use of a device placed on the participant's head (HDM-Head Mounted Display) which can cause dizziness and back pain in some participants and limits the therapist-patient communication. An improved version of the AR system based on projection helps to solve this problem, allowing a more natural interaction with the stimulus and the therapist and greater comfort. The preliminary efficacy of this system has been tested in a case study but, so far, there is no RCT evaluating the efficacy of this AR system. Therefore, in this work two objectives are pursued, firstly, to test and validate a projection-based AR system in the phobia of cockroaches treatment and, secondly, to evaluate the clinical potential of the eye-tracking technology as a specific measure to assess changes in cognitive processes.

The Randomized Clinical Trial (RCT) will be conducted following the Consolidated Standards of Reporting Trials (CONSORT: http://www.consort-statement.org) and the SPIRIT guidelines (Standard Protocol Items: Recommendations for Intervention Trials). Participants (N=96) will be randomized into three groups (after receiving a SP diagnosis - DSM-5): 1) Projection-based augmented reality therapy (P-ARET); 2) In vivo Exposure therapy (IVET); and 3) a waiting list control group (WL). Participants in the WL will be randomly assigned to one of the two treatment conditions after spending time on the waiting list (1 week) for ethical reasons. Outcome measures will be assessed at baseline, post-treatment and 1-, 6-, and 12-month follow-ups.

Inclusion criteria

• Being at least 18 years old
• Meeting DSM-5 diagnostic criteria for SP (animal subtype) to cockroaches
• Having a minimum of six-month duration of the phobia
• Sign an informed consent
• Presenting a score of at least 4 on the fear and avoidance scales of the diagnostic interview applied

Exclusion criteria

• Presence of another severe mental disorder that requires immediate attention
• Having current alcohol or drug dependence or abuse, psychosis or severe organic illness
• Currently being treated in a similar treatment program
• Being capable of inserting their hands in a plastic container with a cockroach (during the behavioral test)
• Receiving other psychological treatment during the study for cockroach phobia
• Start receiving pharmacological treatment during the study (or in case of being already taking them, change the drug or dose)