July 4, 2014
Researchers Work To Understand How Psychedelics Affect The Brain
Alan McStravick for redOrbit.com - Your Universe Online
Researchers from the UK and Germany have opened the door on the little understood subject of just how psychedelic substances work within and affect our brain and our perception of consciousness. With the combination of heightened visual and auditory perception, a description that often accompanies a mind-expanding drug trip has been 'dream-like'. According to the results of a study recently published in the journal Human Brain Mapping, that description is more accurate than we knew.
During an experience with a psychedelic drug a user will often come out describing the experience as having been one that expands their consciousness. This expansion can be from enhanced associations, vivid imagination and dream-like states. As the study results indicate, psilocybin produced a higher than normal level of activity in the more primitive brain network that is linked to our emotional thinking. Specifically, the hippocampus and the anterior cingulate cortex were highly active at the same time. This brain activity is very similar to patterns observed in other studies of people who are asleep and in a period of dream state.
Also of interest was the fact that those individuals experiencing the effects of psilocybin presented diminished, disjointed and uncoordinated activity in the brain network linked to higher-level thinking. Basically, while under the influence, individuals have a far lower perception of their own self-consciousness.
"What we have done in this research is begin to identify the biological basis of the reported mind expansion associated with psychedelic drugs," said Dr. Robin Carhart-Harris from the Department of Medicine, Imperial College London, in a recent statement. "I was fascinated to see similarities between the pattern of brain activity in a psychedelic state and the pattern of brain activity during dream sleep, especially as both involve the primitive areas of the brain linked to emotions and memory. People often describe taking psilocybin as producing a dreamlike state and our findings have, for the first time, provided a physical representation for the experience in the brain."
To arrive at their study results the researchers focused on examining the variation in the amplitude of fluctuations in what is called the blood-oxygen level dependent (BOLD) signal. The BOLD signal tracks activity levels in the brain. It was through this method the team learned that high-level thinking associated with particular brain networks became unsynchronized and disorganized under the chemical that gives mushrooms their psychedelic properties. In particular, one area that is responsible for what the researchers explain as 'holding it all together' is significantly impacted. This same area is linked in helping humans to perceive their sense of self.
While at the same time we seem to lose ourselves in the psychedelic experience, areas of the brain associated with memory, emotion, arousal and creativity go into overdrive. The psilocybin actually brings these multiple regions into a state of synchronicity.
Serving as lead author on the study, Dr. Enzo Tagliazucchi of Germany's Goethe University explained, “A good way to understand how the brain works is to perturb the system in a marked and novel way.” Continuing he said, “Psychedelic drugs do precisely this and so are powerful tools for exploring what happens in the brain when consciousness is profoundly altered.” Tagliazucchi claimed this study presented a first in brain research and the results have been particularly enlightening in how psychedelic drugs expand the mind. “It really does provide a window through which to study the doors of perception.”
Echoing his colleagues’ sentiment, Carhart-Harris added, “Learning about the mechanisms that underlie what happens under the influence of psychedelic drugs can also help to understand their possible uses. We are currently studying the effect of LSD on creative thinking and we will also be looking at the possibility that psilocybin may help alleviate symptoms of depression by allowing patients to change their rigidly pessimistic patterns of thinking.” Discussing the history of psychedelic study and use, Carhart-Harris continued, “Psychedelics were used for therapeutic purposes in the 1950's and 1960's but now we are finally beginning to understand their action in the brain and how this can inform how to put them to good use.”
The initial collection of data was performed at Imperial College London in 2012. The original team was able to infer a variety of changes in the brain associated with drug intake. This latest study was made possible by the recruitment of professors Dante Chialvo and Tagliazucchi, experts in the field of mathematical modeling of brain networks, to investigate how psilocybin alters brain activity to produce unusual psychological effects.
The new study employed the use of the measurement of entropy. Originally designed as a means to quantify energy loss in mechanical systems, entropy can also be used to determine the range of randomness occurring in a system. Through the use of entropy measurement, the team noted the more primitive brain networks experienced a remarkable increase. This was indicative of a marked increase in the overall number of patterns of activity that became possible under the influence of psilocybin. As the team explains, participants injected with psilocybin had a much larger range of potential brain states available to them. This coordinated but randomized system activity could possibly be explained as being the biophysical counterpart of 'mind expansion' that is often reported by users of psychedelic drugs.
Before this study researchers claimed the brain typically operated with an optimal number of dynamic networks active. This idea, they believe, may have provided an evolutionary advantage to humans as it would explain the tight balance we hold between the stability and flexibility of the state of consciousness. We are able to navigate our day-to-day lives best when our brains are able to traverse the thing but necessary path between order and disorder. This most recent study, with the first ever understanding of actual brain processes during a period of psychedelic drug use, suggests that psilocybin is able to shift the fulcrum upon which our brain activity balances, thus manipulating this critical operating point.