The Book in a Nutshell
In How to Change Your Mind, Michael Pollan explores the history of the science of psychedelics. The book unearths the early findings on the role of psychedelics in treating anxiety, depression, and addiction, as well exploring the cutting-edge research at the forefront of the psychedelic resurgence of the 21st century. In a compelling read, Pollan also documents his first-hand experience with psilocybin, LSD, and other psychedelics.
Book Summary: The Key Ideas
#1: The evolution in psychedelic studies. Following a flood of academic interest in the 1950s and 1960s, the study of psychedelics faded out from the mainstream for decades. Recently, as authorities look for alternative solutions to growing mental health problems, their study has experienced a resurgence of interest.
#2: The four hallmarks of mystical experiences. The uniqueness of psychedelics as a treatment is in their capacity to provoke “mystical experiences”. Such experiences are characterised by a noetic quality, ineffability, a sense of surrendering to a superior force, and enduring aftereffects.
#3: The neuroscience of psychedelics. Brain-scanning studies have revealed that the mind-wandering region of brain appears to become less active on psychedelics. At the same time, regions of our brain become less specialised and more connected, perhaps explaining how we produce mystical experiences.
#4: Psychedelics as a treatment. A growing pool of research suggests that psychedelics may be a useful intervention for cancer anxiety, treatment-resistant depression, alcoholism and other addictions.
Book Notes: The Key Ideas in Detail
The following are more detailed book notes on the key themes from How to Change Your Mind. These notes do not by any means cover the full breadth of the book. They are instead intended to serve as an introduction to some of the key ideas, from which to decide whether the book is worth further attention.
Key Idea #1: The Challenges of Studying Psychedelics
In the 1950s and 1960s, there was a flood of scientific interest in psychedelics as a potential treatment pathway for a range of health problems. But as cultural pressures and illegalisation took hold in subsequent decades, this research was cast aside by the mainstream.
In recent years, however, there has been a renaissance of interest. Against the backdrop of rising mental health problems, authorities are now looking for alternative solutions. Researchers are unearthing the wealth of historical research and building upon it with cutting-edge techniques such as functional magnetic resonance imaging (fMRI) of the brain.
Such studies were suppressed for decades not only because of cultural pressures, but because psychedelics are inherently tricky to study.
One problem is “expectancy effects”. If we’re told we’ll have a spiritual experience or experience temporary madness, there is a better chance we will “construct” that reality.
Similarly, set and setting play a critical role in moulding the experience of psychedelics. And of course, the study of subjective consciousness also relies on individual testimony. This makes it difficult to isolate a single variable in the experience of participants.
Key Idea #2: The Four Hallmarks of Mystical Experiences
Despite these challenges, central to the purported benefits of classic psychedelics are their non-addictive quality and the so-called “mystical experiences” they provoke.
Williams James believed there were four hallmarks to such mystical experiences:
- A noetic quality: This is the idea that the person feels they have been shown a fundamental truth about the universe. “Dreams cannot stand this test,” James wrote.
- Ineffability: Mystical experiences often defy expression and cannot be put into words (albeit a potentially convenient advantage when researching these experiences).
- Transiency: The traces of a mystical experience persist and recur for some time as we perceive the world around us thereafter. This is often referred to as the “afterglow”.
- Passivity: This is the sense of temporarily surrendering to a superior force.
In conjunction, these four hallmarks appear to have a remarkable effect on many individuals.
Key Idea #3: The Neuroscience of Psychedelics
The classic psychedelics (e.g. psilocybin and LSD) belong to a group of molecules known as tryptamines. This group of molecules has a particular affinity with a serotonin receptor, and they resemble serotonin such that they can activate this receptor.
Since the 2000s, researchers have explored the specific effects of this neurochemistry on neural activity via fMRI and MEG studies.
These studies point at two important findings:
Finding 1: The default-mode network (DMN) becomes less active on psychedelics. The DMN is the area of the brain which becomes active when we are doing nothing. It’s the mind-wandering pathway and it’s associated with mental constructs – most notably, our ego.
Strikingly, when psilocybin trips were reported to be most associated with a sense of loss of self, the degree of reduction in DMN activity was greatest. This provides neurological weight to the argument the psychedelics help us to dissolve our egos.
Interestingly, as DMN influence declines, we also score ourselves as closer to nature. To paraphrase Pollan, it’s therefore possible that hippies don’t gravitate to psychedelics; psychedelics create hippies!
Finding 2: Brain networks become less specialised and more connected on psychedelics. Psychedelics appear to increase the amount of “entropy” in the brain, reverting our brain to less constrained cognition. Brain scans show that new connections emerge on psychedelics and regions become less specialised.
It’s possible that the convergence of usually distinct networks explains the manifestation of mental experiences on psychedelics. If psychedelics increase creativity, this higher “entropy” might explain why.
There remains some debate about how the effects of psychedelic experiences on the brain might endure over the longer term. But some have argued that psychedelics may help to increase neuroplasticity (that’s our brain’s ability to change shape, size and activity in response to new stimulus).
Key Idea #4: Psychedelics as a Treatment
While there are noted difficulties with studying psychedelics, with mental health problems at a height not seen before, authorities are more willing to approve their study.
Research thus far has important and encouraging implications for a number of areas:
Cancer Anxiety: Studies looked at the use of psilocybin to treat cancer anxiety and found that some 80% of cancer patients showed significant reductions in anxiety and depression. The intensity of participants’ mystical experience closely correlated with the degree of reduction in anxiety and depression.
Individual testimonies suggest experiences provided participants with powerful feelings of connection with loved ones and allowed participants to diminish the relative importance of their illnesses in comparison.
Addiction: In a small study of smokers who received CBT followed by 2 to 3 doses of psilocybin, 80% were abstinent after 6 months and 67% after 1 year. Notably, that’s a better success rate than the best treatment currently available. Again, the most complete mystical experiences were linked with the best outcomes.
LSD has also been found to help reduce alcohol dependency. Subsequent studies with psilocybin and motivational therapies echoed these findings.
Pollan argues that a kind of “overview effect” may play an important role here. Experiences seemed to give participants a view their own lives that allowed them to let go of and/or change habits.
Depression: There is a hypothesis that depression may be linked with an overactive default-mode network, the brain region where rumination takes place. This might explain the early success of studies aiming to address treatment-resistant depression.
All in all, while research is ongoing, psychedelics appear to offer some strong and sustainable benefits for many participants. Pollan attributes a large portion of this success to the unique capacity of psychedelics to temporarily dissolve the ego.
For health problems like anxiety, addiction and depression, the capacity to evoke perspective-lending, awe-striking experiences may offer a new pathway to treating these problems in an affordable and natural way.