Psychedelics are a class of drugs which have been at the centre of much scientific, social and political controversy in the 20th century. Some believe that these drugs “open” or “expand” the mind, allowing spiritual understanding or greater connection to others. Others think that they merely put a magnet next to the compass of the mind, setting it on a course to madness.

Some researchers believe that they could be a useful tool in psychological therapy. Many people have tried to use them to gain spiritual and transcendent experiences and most governments have banned their use.

The first thing to clarify: what are psychedelics? Psychedelics are drugs that affect the human brain, specifically their senses, perception, and cognition. The relationship between what a person’s senses tell them and what they perceive is how a person judges what is real and what isn’t, and by interfering with this relationship psychedelics create experiences such as hallucinations. Indeed, psychedelic drugs are part of a larger group of drugs: the hallucinogens.

Drugs have an effect on the brain by acting on the chemicals that different parts of the brain use to talk to each other. The fancy name for these chemicals is neurotransmitters (neuro=related to nerves and transmit=to send over, so neurotransmitters send stuff between nerves). The neurotransmitters dopamine and serotonin are frequently targeted by drugs designed to affect the brain. These neurotransmitters (or chemicals that are very similar) also have jobs outside the brain, for instance serotonin is used to coordinate the gut. Therefore all drugs that act on the brain can have some rather unpleasant or dangerous side effects.

Different psychedelics work in different ways, affecting different parts of the brain, a person’s senses and/or the way their brain interprets the information from those senses. Some psychedelics affect the information coming into a person’s brain from their senses. Others bind to the serotonin receptors in the brain and affect the release of other neurotransmitters (e.g. dopamine) and hormones (e.g. oxytocin and cortisol). The resulting disassociation between senses and interpretation or sudden release of chemicals in the brain results in experiences commonly known as ‘trips’.

LSD (lysergic acid diethylamide) is perhaps the most well-known ‘trip-inducing’ drug, causing effects such as dizziness, numbness, and rapid emotional shifts that can range from fear to euphoria. The transitions between these emotions can be so rapid that a person seems to experience several emotions at once. Other psychedelics such as Ayahuasca produce hallucinations - ayahuasca is noted for a profoundly altered state of awareness, and perceptions of otherworldly imagery, while DMT (dimethyltryptamine) hallucinations frequently involve altered environments as well as body and spatial distortions.

Psychedelic drugs can be both natural and man-made: ibogaine occurs naturally in the West African shrub iboga, while ayahuasca is a psychoactive tea made with several herbs including the vine banisteriopsis caapi.

There are other, more unexpected, trip-inducing drugs. For instance caffeine. Yes, Caffeine, the active ingredient of coffee. Admittedly you would have to take dangerous quantities of caffeine to notice anything and you would probably die in the process. And there is a limit to how much coffee even science writers can drink. Perhaps the most unexpected is nutmeg, which has been reported to induce hallucinations. However it does also produce some rather unpleasant side effects, so don’t put too much of it in your coffee.

The fact that these experiences are so odd, and that they are found in many plants, means that people have been using drugs for a very long time, especially in religion or when trying to see the future.

Some drugs can even induce hallucinations by not being taken. One of the symptoms of severe alcohol withdrawal (Delirium Tremens) is hallucinations.

People are all different and complicated. This means it can be difficult to predict how much a drug will help people and how bad the side effects of drugs can be. Therefore a drug must go through a lot of trials on lots of people before it can be accepted as a treatment. This is a very slow and expensive process which hinders research. It can also make drugs which have already existed for a long time difficult to study because they are difficult to patent. Without a patent the organisation which did the study can’t really make much money from selling the drug afterwards, so companies don’t have an incentive to fund these studies.

Another problem with studies on psychedelics is that people generally notice when you give them psychedelics. This may sound trivial but when it comes to drug research it can be a real headache because in order to be sure that it is the drug that is having the effect, you have to be sure the effect is real and not caused by the person expecting to have something happen to them.

This “expectation effect” is called the placebo effect. During most drug experiments, neither the participant nor the person giving the drug knows whether the participant has been given a drug, or an inactive dud (often called a placebo, since it only has a placebo effect). This is called a “double blind trial” because both participant and drug source are “blind” to what is in the treatment. Double blind trials are almost impossible to do on psychedelics because trips are rather unusual experiences, so it is pretty obvious if you have been given a real drug rather than a placebo. The upshot is that it is difficult to be certain that what we see in experiments is actually due to the drug, since the placebo effect can’t be easily accounted for.

Compared to other types of drug, hallucinogens haven’t really had that much work done on them. This means that it will be a long time before they can be accepted as treatments, even if they continue to be studied.

All that said, mental health problems can ruin, and sometimes end lives. They also remain difficult to treat. No wonder mental health problems cost £22.5 billion a year to treat in England alone. So perhaps any potential improvement to treatment is worth pursuing.

Other potential uses of psychedelic drugs, such as to gain religious experience or aiding self understanding are unlikely to receive as much funding as medical uses. This means we cannot study, and therefore be certain of, their effectiveness.

In summary it is difficult to answer Darius’ question “Could psychedelic drugs aid empathy and understanding?” because of the way that scientific experiments on drugs work.

References and further reading:

Hallucinogens as Medicine:

“Direct costs of mental health in England are now around £22.5 billion a year”:

Attempting to study the effects of LSD:

Placebo effect:

Use of narcotics in history:

Why am I hallucinating?

Caffeine overdose:

Alcohol withdrawal: