Trauma cue-induced affect, craving, and automatic cognitons in cannabis users with trauma histories

Abstract

There is an elevated prevalence of cannabis use among trauma-exposed individuals. Moreover, posttraumatic stress disorder (PTSD) and cannabis use disorder (CUD) are highly comorbid. Frequent pairing of trauma cues with cannabis use may lead to classically conditioned cannabis craving on future trauma cue exposure. Similarly, through strong memory associations formed between trauma cues, negative affect, cannabis use, and relief outcomes, trauma cue exposure should theoretically elicit both negative affect and automatic cannabis-relevant cognitions (e.g., cannabis approach bias) that promote cannabis use. Theoretically, these conditioning processes should be particularly strong in those with PTSD and could serve as mechanisms underlying PTSD-CUD comorbidity. In this dissertation, I conducted a scoping review and four experimental studies to test predictions arising from these classical conditioning and associative learning models among trauma-exposed substance/cannabis users. Study 1 mapped existing research on experimental trauma/substance cue exposure in substance users with trauma histories/PTSD, identifying gaps, methodological challenges, and common responses elicited by trauma cue reactivity paradigms (CRPs). Four subsequent empirical studies focused on testing effects of trauma cue exposure, PTSD, and their interactions on relevant cognitive and affective outcomes in cannabis users with trauma histories. Study 2 showed a single-session trauma CRP (semi-structured personalized trauma interview) elicited greater cannabis craving and negative affect (particularly in those with more PTSD symptoms) compared to a neutral interview. Study 3 investigated effects of trauma cue exposure (semi-structured interview) and PTSD symptom severity on cannabis approach bias, revealing a positive association between PTSD symptoms and this automatic cognitive bias. Study 4 tested another trauma CRP (online expressive writing); trauma vs. neutral writing and likely PTSD were both independently associated with greater negative affect and cannabis expectancy craving. Study 5 examined effects of trauma cue exposure (expressive writing) and likely PTSD on the accessibility of cannabis-related information in memory; trauma (vs. neutral) writing elicited greater cannabis accessibility. Collectively, my studies contribute to understanding mechanisms underlying co-occurring PTSD-CUD, suggesting contributions from both trauma cue-elicited automatic and controlled cognitive processes, as well as conditioned negative affect. My dissertation also contributes methodologically by validating two single-session CRPs (interview; expressive writing) for future use in this field.