An Event-Related Potential Study on the Effects of Cannabis on Emotion Processing

Abstract

The effect of cannabis on emotional processing was investigated using event-related potential paradigms (ERPs). ERPs associated with emotional processing of cannabis users, and non-using controls, were recorded and compared during an implicit and explicit emotional expression recognition and empathy task. Comparisons in P3 component mean amplitudes were made between cannabis users and controls. Results showed a significant decrease in the P3 amplitude in cannabis users compared to controls. Specifically, cannabis users showed reduced P3 amplitudes for implicit compared to explicit processing over centro-parietal sites which reversed, and was enhanced, at fronto-central sites. Cannabis users also showed a decreased P3 to happy faces, with an increase to angry faces, compared to controls. These effects appear to increase with those participants that self-reported the highest levels of cannabis consumption. Those cannabis users with the greatest consumption rates showed the largest P3 deficits for explicit processing and negative emotions. These data suggest that there is a complex relationship between cannabis consumption and emotion processing that appears to be modulated by attention.

The relationship between cannabis use and measures of anxiety and depression in a sample of college campus cannabis users and non-users post state legalization in Colorado

“…While there were other measures included in our questionnaire packet, the hypotheses of this study focus on the CES-D and STAI survey scores. Scores on the R-CUE were used to determine cannabis use and user profiles and groupings (casual and chronic) were consistent with previous research (e.g., Degenhardt, Hall & Lynskey, 2003; Morgan et al, 2012; Troup et al, 2016); a participant was considered a chronic user if they used once a week or more, less use was considered casual. Eight groups in total were created based on frequency for creating categories of cannabis use, and cutoffs for categorizing anxiety and depression: pre-depressed users, non-depressed users, pre-depressed non-users, non-depressed non-users, pre-anxious users, non-anxious users, pre-anxious non-users, and non-anxious non-users.…”

“…It should also be noted that this study serves as a population pilot for future research using ecological approaches to the possible contributions cannabis use has to pre-mood/anxiety disorder symptoms within the population; therefore, our sample size will be smaller than typical ecological research. Based on our previous research (Troup et al, 2016) we expected to see a significant relationship between cannabis use and scores on mood and anxiety measures, with individuals who are heavy cannabis users showing a significantly higher incidence of anxiety and depression scores consistent with the cut offs described by the STAI and CES-D in the literature. Further, exploratory analysis will allow us to look more closely at these relationships as drivers for future research directions.…”

“…However, to reduce complexity in the data our analysis focused on the CES-D and STAI. Finally, they completed the R-CUE, a self-reported cannabis use questionnaire developed to address cannabis use in Colorado post legalization (Troup et al, 2016). The R-CUE is a measure of cannabis use patterns developed specifically for research in our laboratory post cannabis legalization in Colorado.…”

“…However, mood and anxiety disorders (with the exception of PTSD in 11 states) are currently not an approved condition in any of these states, although Canada has mood and anxiety disorders as approved medical conditions in their Medical Marijuana Access Division (https://medicalmarijuana.ca/for-patients/who-is-eligible). Recent research in our lab (Troup et al, 2016) investigated the residual effects on cannabis and emotion processing in an event-related potential paradigm. We looked at explicit, implicit and empathic response to negative and positive emotional expressions and the effect this had on the P300 Event Related Potential (ERP).…”

“…Cannabis use patterns were determined using the Recreational-Cannabis Use Evaluation (R-CUE), a questionnaire developed specifically for assessing cannabis use in post-legalization Colorado. Cannabis use led to a reduced P300 in cannabis users in implicit and empathic emotional processing for negative emotional expressions (Troup et al, 2016). …”