Why do cannabis users sometimes have difficulty speaking? Landmark study reveals how the drug impacts motor neurons
They found compounds inhibit information that reaches these neurons
They found compounds inhibit information that reaches these neurons
Marijuana users can sometimes have difficulty speaking, breathing and swallowing food as a result of muscle weakness.
Now researchers in Spain have conducted a landmark study to shed light on how marijuana reduces the activity of motor neurons that lead to these symptoms.
Motor neurons are nerve cells found in the cerebral cortex of the brain stem, and are responsible for giving orders to muscles in the body.
Researchers at the University of Cadiz, led by Professor Bernardo Moreno, used synthetic analogues of the psychoactive compounds of marijuana to see how they affected these neurons.
They looked, in particular, at movements of the tongue and how they responded to the drug.
'During the investigation, we used an animal model in which we studied the alterations produced by synthetic cannabinoids on the activity of the motor neurons,' the researchers wrote. 'In doing so, we discovered that these psychoactive compounds inhibit the information that reaches these neurons via the synapses. 'In other words, cannabinoids hinder the transmission of information between neurons.' All of this could lead to problems speaking, breathing and swallowing food. But the same reaction could also explain the beneficial effects that marijuana has on people suffering from neurodegenerative diseases such as multiple sclerosis. The scientists say that by reducing motor neuron activity, people with multiple sclerosis may have temporary relief from their symptoms. Last week, scientists at the Yale University School of Medicine said they had discovered how cannabis flicks a switch in the brain that turns on hunger. Research into how the drug affects our brains has revealed it actually suppresses the circuitry controls appetite and allows us to feel full. The researchers bred mice that had differences in their nerve signalling and monitored their brain activity after they were exposed to the drug. The study, published in the journal Nature, revealed that mice who had been exposed to cannabis felt hunger, or the munchies. This was because the brain circuitry that normally made them feel full was instead being used to make them feel hungry, it was found.