Singular and combined effects of transcranial infrared laser stimulation and exposure therapy: A randomized clinical trial.

This RCT will test whether transcranial infrared laser stimulation (TILS) administered immediately following standard exposure therapy enhances the retention of fear extinction for naturally acquired pathological fear. A second aim is to investigate the efficacy of TILS as a stand-alone intervention for reducing pathological fear. Participants with elevated fear in any one of the following four domains: (a) fear of enclosed spaces, (b) fear of contamination, (c) fear of public speaking, or (d) fear of anxiety (i.e., anxiety sensitivity) will be recruited from introductory psychology classes and the greater Austin community. Participants displaying marked fear responding will be stratified on baseline fear responding and fear domain and randomized to one of four treatment arms: (1) Exposure + TILS, (2) Exposure + sham TILS, (3) TILS alone, or (4) Sham TILS alone. We anticipate that TILS will enhance exposure therapy outcome relative to sham TILS and that this enhancement effect will be most pronounced for (a) those displaying higher baseline fear responding, and (b) those showing greater fear reduction during exposure. Study rationale as well as additional predictions and clinical implications are discussed.