Clinical trials

The purpose of this study is to investigate the effects of increasing brain energy on cognition. The hypothesis is that by using a special kind of light, in combination with a nutritional supplement, it may be possible to increase energy production in the brain, which may lead to improvements in cognition.

The investigators have previously shown that non-invasive methods of brain stimulation such as the administration of transcranial infrared light to the prefrontal cortex (PFC) can result in improvements to cognition and emotion as well as brain oxygenation. This method is called transcranial photobiomodulation (tPBM). The investigators hypothesize that tPBM can improve cognition and brain oxygenation in adults with attention deficit hyperactivity disorder (ADHD). The investigators will investigate the effects of repeated tPBM sessions on cognitive functioning in adults with ADHD. Specifically, the investigators hypothesize that participants that receive tPBM will show improvements in response control, sustained attention, and working memory, as well as improvements in prefrontal hemodynamics and a reduction in ADHD symptoms.

The investigators have previously shown that the administration of low-level infrared light is a safe and non-invasive procedure which improves cognition and emotion, as well as enhances brain metabolic activity. Based on previous studies, the investigators hypothesize that this methodology, called low-level light therapy or photobiomodulation, could be used to improve behavioral symptoms in individuals with autism spectrum disorder (ASD).

Inattentiveness and impulsivity in healthy adults and individuals with attention deficit hyperactivity disorder (ADHD) diminish these individuals' quality of life. Cortical hypometabolism has been hypothesized to contribute to inattentiveness in ADHD. Transcranial photobiomodulation (tPBM) is a safe and non-invasive modality for activation of the prefrontal cortex. tPBM in healthy adults has been shown to augment brain oxygenation, cognition, and mood. The cognition-enhancing effect of tPBM on sustained attention in adults with ADHD remains unstudied. The investigators will evaluate whether tPBM administration to adults with and without ADHD can improve their attention. Each participant will be screened for eighteen criteria based on the Diagnostic and Statistical Manual (DSM-IV, text revised), using the validated instrument Adult ADHD Self-Report Scale (ASRS-v1.1). Blinded participants will be randomized into (I) Active-tPBM or (II) Sham-tPBM groups. After undergoing an 8-minute administration of Sham or 1064 nm tPBM to the lateral and medial right prefrontal cortex, each participant will complete a 14-minute, computer-based Conner's continuous performance task-3 (CPT-3). The investigators will examine whether adults with and without ADHD who receive Active-tPBM improve in measures of inattention, impulsivity, sustained attention, or vigilance compared to the Sham-tPBM group. Cognitive assessments of attention like the CPT-3 may evaluate the efficacy of tPBM to increase cortical metabolism in healthy adults and individuals with conditions like ADHD. The investigators anticipate their investigation will be a starting point for more sophisticated studies that focus on the implications of tPBM on cognition.

The investigators have previously shown that safe, non-invasive methods of brain stimulation such as the administration of transcranial infrared light can result in improvements to cognition and emotion. The investigators hypothesize that transcranial photobiomodulation (tPBM) can be used in conjunction with attention bias assessment and modification to reduce anxiety symptoms in individuals with sub-clinical anxiety.