A study of people with cannabis use disorder in Australia found no evidence that they paid more attention to pictures of cannabis than people who did not suffer from cannabis use disorder. The paper was published in General psychiatry.
Cannabis use disorder is a mental health condition characterized by a problematic pattern of cannabis use that causes significant impairment and distress. This occurs when a person continues to use cannabis despite experiencing negative effects in their daily life.
People with this disorder may have difficulty controlling how often and how much they use cannabis. They may spend a lot of time consuming, using, or recovering from the effects of cannabis. Another common characteristic is craving, which refers to a strong desire or urge to use the substance. People with cannabis use disorders also tend to develop tolerance, requiring larger amounts of cannabis to achieve the same effects.
When people stop using cannabis, some people experience withdrawal symptoms such as irritability, trouble sleeping, and loss of appetite. This disorder can interfere with responsibilities at work, school, or home. It can also lead to social or interpersonal problems associated with cannabis use.
Study author Marianna Quinones Varela and her colleagues wanted to investigate how attentional biases toward cannabis-related photos (vs. neutral photos) differed among individuals with moderate to severe cannabis use disorder who were not seeking treatment or control participants, taking into account alcohol consumption in the past month. They also wanted to see if the strength of this attentional bias depended on the amount of cannabis used, cannabis craving, cannabis-related problems, and a number of other characteristics.
Study participants were 108 people recruited from the Melbourne metropolitan area (Australia) through flyers in the general community, university campuses, and online platforms. Participants were required to be between 18 and 55 years of age, have normal or corrected-to-normal vision, and be fluent in English. Participants with cannabis use disorder also had to report daily or near-daily cannabis use for at least the past 12 months and meet diagnostic criteria for moderate-to-severe cannabis use disorder.
Study participants completed assessments of anxiety (State-Trait Anxiety Index – Y Form), and depressive and psychotic symptoms (Community Assessment of Psychological Experiences). They also completed a clinical interview to ascertain the severity of their cannabis use disorder, reported their motivation to change their cannabis use habits (Reflection Ladder), and completed an assessment of problematic alcohol use (Alcohol Use Identification Test).
Attentional bias was measured using a task in which participants saw and responded to pictures. There were 10 pairs of cannabis and neutral images. The cannabis images included photos of cannabis, people using cannabis, and photos of cannabis paraphernalia. Neutral images included people and objects that matched cannabis images in terms of composition, complexity, brightness, and color.
For this task, we first briefly displayed cannabis and a neutral image side by side. One of those images was then replaced with an arrow, and participants had to indicate the direction of the arrow. The idea is that if participants show an attentional bias toward cannabis (i.e., images of cannabis attract more attention than neutral images), they will respond faster to arrows that replace images of cannabis because their gaze and attention are already directed to that location before the arrow appears (and thus they do not need to shift their gaze to see the arrow). Each participant completed 164 of these trials, lasting approximately 15 minutes in total.
This result did not support the prediction that participants with cannabis use disorder would have a stronger attentional bias towards pictures of cannabis compared to the control group. However, among participants suffering from cannabis use disorder, those with more severe symptoms tended to have very slightly faster reaction times when an arrow appeared on a cannabis image compared to a neutral image. However, this difference was very small, and it remained unclear whether it was a systematic difference or caused by random variation in participants’ responses.
“Although attentional bias may not be a strong feature of CUD (cannabis use disorder), this concept requires validation in larger samples using more direct measures of attentional bias,” the study authors concluded.
This study contributes to scientific knowledge about cannabis use disorder. However, it should be noted that reactions to photos of cannabis shown temporarily may not adequately reflect how people would react to cannabis in real-world situations. The study authors also note that the sample may not actually be representative of the general population of individuals with cannabis use disorder due to the fact that they selected participants with cannabis use disorder who did not suffer from other mental illnesses.
The paper, “Attention Bias in People with Moderate to Severe Cannabis Use Disorder,” was authored by Marianna Quinones Varela, Gary Chan, Madeline I. Fraser, Andrew Jones, Tom P. Freeman, Chandni Hindocha, Hannah Thomson, Eugene McTavish, Hannah Seal, Adam Clemente, Gianna Kuzin, Iselle Labuschagne, and Peter. Rendell, Gil Terret, Lisa-Marie Greenwood, Govinda Poudel, Chaosuo, Victoria Manning, and Valentina Lorenzetti.
