The effects of the laughing gas on humans have always gained attention from both the public and from scientists. How it actually modifies the brain though has remained much of a mystery. Researchers from the Massachusetts Institute of Technology (MIT) have attempted to shed light on the changes it brings on one’s brainwaves, and concluded that it might perhaps be turned into an anaesthetic in the future; but that might also be tricky. The findings have been published in the journal Clinical Neurophysiology.
Photo credits: Jose-Luis Olivares/MIT.
Nitrous oxide is used either at the end of the surgery when more potent anesthetics start to fade from the system, or in combination with the main anesthetics to reduce the dose.
The MIT researchers set out to find out about its effects on patients. The latter’s brain activity under anesthetics was analysed using an electroencephalogram (EEG). The changes in electrical activity occurring as the neurones in their brains communicated with each other was measured.
Upon observing patients’ brains under the effect of anesthetic doses of nitrous oxide three minutes after administration, the researchers recorded “large-amplitude slow-delta waves”. The latter would move from the front to the back of the brain every 10 seconds. This effect normally occurs in people in deep sleep stages. However, the brain waves seen were about two times larger than those experienced in normal sleep.
“We literally watched it and marveled, because it was totally unexpected,” said one of the authors, Emery Brown, professor of Medical Engineering at MIT. “Nitrous oxide has control over the brain in ways no other drug does.”
The researchers were amazed to come across such a finding.
“It’s hard to imagine that in 2015 you can just anecdotally observe this.”, said Brown.
According to the interpretation of the authors, the gas might be obstructing signals from the brain that normally operate to keep the person awake. The gas is known to bind to receptors in some regions of the brain thereby interrupting the latter from receiving the signals associated with consciousness. This is indicated by slower brainwaves.
However, they cannot as yet understand as to why the brainwaves observed only happen in the first three minutes. As a matter of fact, the patients still continued breathing the gas even after the three minutes. Brown has suggested that if they could extend this three-minute deep slow-wave brain activity, they might use the gas as a potent anesthetic, specially that nitrous oxide generates fewer side-effects.