“This study is a first step in uncovering how we can mitigate risks of THC when used in medicine, and also is targeted at making cannabis safer for the general, non-therapeutic consumer,” said Dr. Tory Spindle.

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Can cannabis be modified to decrease certain side effects, specifically anxiety, that is caused by tetrahydrocannabinol (THC)? This is what a recent study published in Drug and Alcohol Dependence hopes to address as a team of researchers led by the Johns Hopkins University School of Medicine investigated whether adding d-limonene, which is a known cannabis oil, to THC could help alleviate common feelings of anxiety or paranoia that cannabis users traditionally experience. This study holds the potential to help improve medicinal cannabis while decreasing risks to users of recreational cannabis, as well.

For the study, the researchers enlisted 20 healthy adult participants with an average age of 26 years old who completed 10 six-hour sessions involving them using vaporized THC alone (15 mg or 30 mg), vaporized d-limonene alone (1 mg or 5 mg), both together, and finally a placebo. The sessions were double-blinded, meaning both the researchers and participants were unaware who was vaporizing which sample.

While all 20 participated in nine sessions, 12 participants conducted the tenth session comprised of the higher dose of THC and an even higher dose of d-limonene at 15 mg. The goal of the sessions was to ascertain the overall drug effects, specifically vital signs, mood, and cognitive functions, along with blood and urine samples during and after each session to measure THC and d-limonene levels.

Parkinson’s disease is a neurodegenerative movement disorder that progresses relentlessly. It gradually impairs a person’s ability to function until they ultimately become immobile and often develop dementia. In the U.S. alone, over a million people are afflicted with Parkinson’s, and new cases and overall numbers are steadily increasing.

There is currently no treatment to slow or halt Parkinson’s disease. Available drugs don’t slow disease progression and can treat only certain symptoms. Medications that work early in the disease, however, such as Levodopa, generally become ineffective over the years, necessitating increased doses that can lead to disabling side effects.

Without understanding the fundamental molecular cause of Parkinson’s, it’s improbable that researchers will be able to develop a medication to stop the disease from steadily worsening in patients.

In conventional functional MRI (fMRI), researchers monitor changes in blood flow to different brain regions to estimate activity. But this response lags by at least one second behind the activity of neurons, which send messages in milliseconds.

Park and his co-authors said that DIANA could measure neuronal activity directly, which is an “extraordinary claim”, says Ben Inglis, a physicist at the University of California, Berkeley.

The DIANA technique works by applying minor electric shocks every 200 milliseconds to an anaesthetized animal. Between shocks, an MRI scanner collects data from one tiny piece of the brain every 5 milliseconds. After the next shock, another spot is scanned. The software stitches together data from all the spots, to visualize changes in an entire slice of brain over a 200-millisecond period. The process is similar to filming an action pixel by pixel, where the action would need to be repeated to record every pixel, and those recordings stitched together, to create a full video.

The idea of growing functioning human brain-like tissues in a dish has always sounded far-fetched, even to researchers in the field. Towards the future goal, a Japanese and French research team has developed a technique for connecting lab-grown brain-mimicking tissue in a way that resembles circuits in our brain.

The work appears in Nature Communications.

It is challenging to study exact mechanisms of the brain development and functions. Animal studies are limited by differences between species in brain structure and function, and brain cells grown in the lab tend to lack the characteristic connections of cells in the human brain. What’s more, researchers are increasingly realizing that these interregional connections, and the circuits that they create, are important for many of the brain functions that define us as humans.