Scientists have developed a prototype for an app that’s been designed for cannabis users so that they can determine whether or not they’re actually high.

The app, called “Am I Stoned”, has been created by researchers from the University of Chicago to assess the effects of cannabis on cognitive ability.

Co-authors Elisa Pabon, a doctoral student, and Harriet de Wit, professor in the department of psychiatry and behavioural neuroscience, presented the app yesterday at the Emerging Biology conference in California.

The app, which has been supported by the National Institute on Drug Abuse Grant, provides users with a series of tasks to test the impact of cannabis use on memory, reaction time and attention span.

Pabon and de Wit decided to try the app out on people who regularly use cannabis in order to examine its impact in a “nonlaboratory setting”.

They had volunteers take a pill containing either 0, 7.5 or 15 milligrams of THC (Tetrahydrocannabinol), which is the main psychoactive component of cannabis.

After two and three hours, the participants then partook in a series of tasks, both on a computer and on an iPhone.

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One of the tasks on the iPhone involved tapping two dots as fast as possible with fingers on the non-dominant hand for 20 seconds.

Pabon and de Wit found that the performance of the individuals who had consumed the pills containing THC was impaired for three out of the four computer tasks and one of the iPhone tasks.

The researchers have stated that further research is needed so that they can make alterations to the app.

“The tasks included in the application need to be optimised in a way that avoids floor or ceiling effects, practice effects, and baseline variation,” Pabon told Gizmodo.

“Additionally, the tasks should be short and efficient but also long enough to be effective at catching drug effect.”

Pabon and de Wit stated in their research that the 24 participants of the study were aware of the quality of their performances during the computer and iPhone tasks.