Use of a Novel EEG-Based Objective Test, the Cognalyzer®, in Quantifying the Strength and Determining the Action Time of Cannabis Psychoactive Effects and Factors that May Influence Them Within an Observational Study Framework.

INTRODUCTION: Current methods to detect recent delta-9-tetrahydrocannabinol (THC) use cannot objectively quantify its psychoactive effects (PE). The Cognalyzer®, an electroencephalography (EEG)-based method, detects and quantifies the strength of THC-induced PE on a scale from 0 to 100%. This study assesses the relationship between the magnitude of Cognalyzer® PE predictions and reported subjective drug effects for 4-h post-cannabis inhalation. METHODS: Seventy-five participants were enrolled in the study. Prior to ad libitum cannabis inhalation, an EEG recording episode was completed. Immediately after inhalation, the Drug Effects Questionnaire (DEQ) was administered and another EEG recording performed. For 25 participants, the study ended. For 50 participants, assessments were repeated at 30-min intervals for 4 h. EEG files were blinded and analyzed using two versions of the Cognalyzer® algorithm. The relationship between the Cognalyzer® PE level results and the DEQ was assessed using generalized linear models and multiple regression. RESULTS: There were significant PE increases from pre-cannabis for up to 3.5 h. Mean reports of feeling drug effects were > 0 at all post-inhalation time points (p ≤ 0.024). Furthermore, there were significant relationships between the Cognalyzer® PE and self-reported perception of drug effects (p ≤ 0.001). Subgroup analysis showed that Cognalyzer® PE levels were impacted by cannabis use history, subjective ratings of drug effects, oral fluid THC concentration and the cannabis product inhaled. CONCLUSION: The findings show that the Cognalyzer® can be used to objectively determine the strength of cannabis psychoactive effects that cannabis products create on consumers and how it changes depending on their experience with cannabis. The Cognalyzer® can be used to conduct scientific consumer research to generate trustworthy informational material about the psychoactive experience of cannabis products. For clinical research, the Cognalyzer® can be used to study the pharmacodynamics of cannabinoids or delivery systems, such as nano-emulsifications.

Sensitivity, Specificity and Accuracy of a Novel EEG-Based Objective Test, the Cognalyzer®, in Detecting Cannabis Psychoactive Effects.

INTRODUCTION: Current standards for identifying recent cannabis use are based on body fluid testing. The Cognalyzer® is a novel electroencephalography (EEG) measurement device and algorithm designed to objectively characterize brainwave alterations associated with cannabis. The objective of this study was to assess the accuracy, sensitivity and specificity levels of the Cognalyzer® to characterize brainwave alterations following cannabis inhalation. METHODS: Seventy-five participants, aged 19-55 years, were enrolled, and oral fluid samples were collected pre-cannabis inhalation. EEG and subjective drug effects questionnaire (DEQ) were administered pre- and post-ad libitum cannabis inhalation. Fifty participants remained in the clinic for 4 h post-inhalation. Blinded analyses of the EEG files were conducted by Zentrela Inc. using two versions (V1 and V2) of the Cognalyzer® algorithm. Pre- vs. post-inhalation comparison status was characterized by the Cognalyzer® and summarized for: sensitivity, specificity, accuracy, percent false positive, percent false negative and positive and negative predictive value. The null hypothesis was tested using McNemar's test. Cognalyzer® results pre- and post-inhalation were combined with the oral fluid tetrahydrocannabinol (THC) concentration to evaluate potential to improve current drug testing. RESULTS: The two versions of the Cognalyzer® algorithm had similar diagnostic results. Diagnostic outcomes were improved when participants with missing EEG recordings or electrode placement errors were removed. The Cognalyzer® accuracy was 85.5% and 83.9%, sensitivity was 87.1% and 88.7%, and specificity was 83.9% and 79.0% for algorithm V1 and V2, respectively. Combining Cognalyzer® results with oral fluid concentrations reduced false-positive oral fluid test results by up to 49%. CONCLUSION: The Cognalyzer® characterized brainwave alterations associated with cannabis inhalation with high levels of accuracy in a population of participants with varied cannabis inhalation histories, relative to the comparison standard of pre- vs. post-inhalation status. The Cognalyzer® allows the results to be generalized to the larger population addressing a limitation in currently accepted standards.