Poster No:
478
Submission Type:
Abstract Submission
Authors:
Justine Chen1, Ruizhe Zhang1, Nathan Chabin2, Jalen Grayson1, Alisa Padon3, Lynn Silver3, Dara Ghahremani1
Institutions:
1UCLA, Los Angeles, CA, 2Pitzer College, Pomona, CA, 3Public Health Institute, Oakland, CA
First Author:
Co-Author(s):
Introduction:
Exposure to marketing for legal substances has a significant impact on subsequent substance use, with underage youth especially susceptible to influence. Guidelines for regulating cannabis advertisements are needed to protect underage youth in districts where cannabis is legal. We sought to determine whether neural responses to cannabis advertisements are related to individuals' self-reports of wanting to use cannabis. Based on our prior work, we categorized cannabis ads by those that had high or low appeal to youth based on the Content Appealing to Youth index (Padon et al., 2017, 2018). We hypothesized that, compared to adults, youth would show greater differentiation in neural responses to ads with high vs. low CAY indices in regions responsive to reward and arousal (e.g., ventral striatum and amygdala, respectively), and that responses in these regions would be related to self-reports of liking the ad and wanting to use cannabis.
Methods:
We presented cannabis ads to youth and adults in California (N=77; 38 female; age range: 16-36 years old; M=23.7, SD=6.1) during fMRI scanning. We prepared non-cannabis control ads that closely matched cannabis ads on appearance. After each ad presentation (20 s), participants rated how much they liked the ad before presentation of the next trial (30 cannabis trials, 30 control trials; mixed event-related/blocked design). After the scan, participants viewed each cannabis ad again and indicated how much it made them want to use cannabis. Thirty percent of those scanned used cannabis regularly (>3x/week). Preprocessing was conducted using FMRIPREP, and univariate whole-brain voxel-wise statistics were conducted using FSL's FEAT (voxel height: Z>3.1, cluster: P<0.05; FLAME1). The relationship between neural responses to individual ads and the desire to use cannabis (as well as liking the ad) was assessed using a priori ROI analyses (ventral striatum, amygdala) conducted at the trial level, with parameter estimates for each trial determined using the "Least Squares - Separate" approach (Mumford et al., 2012). Post-hoc ROI analyses were also conducted on clusters that emerged from whole-brain analyses.
Results:
Whole-brain analyses revealed that both adolescents and adults showed greater activation in bilateral occipito-temporal cortex and right middle frontal gyrus (rMFG) for ads with high vs. low appeal to youth. A priori ROI analyses showed a significant interaction effect of age and brain activation on desire to use ratings for bilateral ventral striatum (R: F(1,2185)=11.5, p<0.001; L: F(1,2184)=17.4, p<0.001) and left amygdala (F(1,2192)=6.1, p<0.05). Post-hoc ROI analyses revealed a similar effect in bilateral occipito-temporal cortex (R: F(1,2230)=98.3, p<0.01; L: F(1,2232)=9.7, p<0.01), but no effects were found for rMFG. In all interactions, youth exhibited a positive relationship between brain activation and desire to use while older adults showed no relationship.
Additionally, a priori ROI analyses showed a significant interaction effect of age and brain activation in several ROIs on ad liking ratings: left ventral striatum (F(1,2206)=6.0, p<0.05) and bilateral amygdala (R: F(1,2213)=5.9, p<0.05; L: F(1,2218)=4.2, p<0.05). Bilateral occipito-temporal cortex also showed a significant age interaction in post-hoc analyses (R: F(1,2208)=8.0, p<0.01; L: F(1,2191)=4.7, p<0.05).
Conclusions:
These results indicate that neural responses to cannabis ads within regions that comprise arousal- and reward-related circuitry (i.e., amygdala and ventral striatum, respectively) and also regions that serve high level visual processing, are related to both likability of the ad and, importantly, desire to use cannabis – especially among youth. The findings suggest that marketing material for cannabis can be suggestive to youth by way of activating limbic circuitry. Because these findings are unique to youth, strategies for cannabis marketing policies could potentially take this into account when forming guidelines for advertisers.
Disorders of the Nervous System:
Psychiatric (eg. Depression, Anxiety, Schizophrenia) 1
Emotion, Motivation and Social Neuroscience:
Reward and Punishment
Higher Cognitive Functions:
Decision Making 2
Keywords:
MRI
Other - Cannabis
1|2Indicates the priority used for review
By submitting your proposal, you grant permission for the Organization for Human Brain Mapping (OHBM) to distribute your work in any format, including video, audio print and electronic text through OHBM OnDemand, social media channels, the OHBM website, or other electronic publications and media.
I accept
The Open Science Special Interest Group (OSSIG) is introducing a reproducibility challenge for OHBM 2025. This new initiative aims to enhance the reproducibility of scientific results and foster collaborations between labs. Teams will consist of a “source” party and a “reproducing” party, and will be evaluated on the success of their replication, the openness of the source work, and additional deliverables. Click here for more information.
Propose your OHBM abstract(s) as source work for future OHBM meetings by selecting one of the following options:
I do not want to participate in the reproducibility challenge.
Please indicate below if your study was a "resting state" or "task-activation” study.
Task-activation
Healthy subjects only or patients (note that patient studies may also involve healthy subjects):
Healthy subjects
Was this research conducted in the United States?
Yes
Are you Internal Review Board (IRB) certified?
Please note: Failure to have IRB, if applicable will lead to automatic rejection of abstract.
Yes, I have IRB or AUCC approval
Were any human subjects research approved by the relevant Institutional Review Board or ethics panel?
NOTE: Any human subjects studies without IRB approval will be automatically rejected.
Yes
Were any animal research approved by the relevant IACUC or other animal research panel?
NOTE: Any animal studies without IACUC approval will be automatically rejected.
Not applicable
Please indicate which methods were used in your research:
Functional MRI
Behavior
For human MRI, what field strength scanner do you use?
3.0T
Which processing packages did you use for your study?
FSL
Other, Please list
-
fMRIPrep
Provide references using APA citation style.
Mumford, J. A. (2012). Deconvolving BOLD activation in event-related designs for multivoxel pattern classification analyses. NeuroImage, 59(3), 2636–2643. https://doi.org/10.1016/j.neuroimage.2011.08.076
Padon, A. A. (2017). Youth-Targeted E-cigarette Marketing in the US. Tobacco regulatory science, 3(1), 95–101. https://doi.org/10.18001/TRS.3.1.9
Padon, A. A. (2018). Assessing Youth-Appealing Content in Alcohol Advertisements: Application of a Content Appealing to Youth (CAY) Index. Health communication, 33(2), 164–173. https://doi.org/10.1080/10410236.2016.1250331
No