A new study found that marijuana or cannabis affects a person's ability to identify, process and empathize with emotions such as sadness, happiness and anger.
Led by psychology assistant professor Lucy Troup, researchers from the Colorado State University studied the effects of cannabis on human brain activities.
"We're not taking a pro or anti stance; but we just want to know, what does it do? It's really about making sense of it," said Troup.
The 70 volunteers were either medical or recreational marijuana users under the Colorado Amendment 64 or non-users (control group). The cannabis users ranged from chronic to moderate users.
The research team utilized an electroencephalogram (EEG) to measure the brain activities as they were shown photos of people's faces with various emotions. The technique measures the brain's electrical activities that are triggered by visual attention.
Cannabis users revealed a stronger response to the faces that showed negative emotions, especially to the angry faces compared to the participants in the control group. Cannabis users also showed a smaller response to the faces depicting positive expressions such as happiness compared to the ones in controls.
Apart from measuring the brain activities, the participants were also asked to focus on the emotion and explicitly identify it. The cannabis users and non-users scored the same.
However, when asked to focus on the gender of the face first and then identify the emotion later, the cannabis users had difficulty in implicitly identifying the emotions, suggesting a depressed ability to sense emotions. They scored lower than the non-users in this test. They were also found to have decreased ability to empathize.
The research was published in the PLOS One journal on Feb. 29. Findings suggested that cannabis affects the brain's emotional processing abilities.
In related news, researchers found in an earlier study published last January that among migraine patients who resorted to medical cannabis, migraine attacks dropped from 10.4 percent to just 4.6 a month.
The findings were considered clinically relevant. The same study found that inhaling cannabis was most effective in treating headaches compared to digesting it using edibles. Inhaling cannabis enabled the migraine-healing effect to come much sooner.
Photo : Tanjila Ahmed | Flickr