Can Psilocybin Prevent Dementia? Exploring Its Potential to Protect the Brain

Dementia is a devastating condition that slowly steals memory, thinking skills, and independence. It affects over 55 million people worldwide, and sadly, there are few effective treatments to stop or reverse it. At the same time, major depression—a condition marked by persistent sadness and loss of interest in life—affects around 280 million people globally. Surprisingly, these two conditions share a lot of similarities and are linked in interesting ways.

Studies have demonstrated that people who have suffered from major depression are much more likely to develop dementia later in life. In fact, having depression can increase the risk of dementia by up to 1.5 times. The risk is even higher for those that aren’t properly managing their depressive symptoms. This close correlation has led many scientists to believe that depression might not just be a separate illness, but could also be an early warning sign of dementia.

It leads us to ask an important question. Why are depression and dementia connected?

Our Ever Changing Brains

To answer our question, we need to understand that the brain has the capacity to change. Destructive habits and mental illness can have severe negative consequences on the brain, but the damage is not always irreversible. Our brains have an amazing ability to grow and heal. Deep inside the brain, in a region called the hippocampus—which controls memory and emotions—new brain cells are created throughout life in a process called adult hippocampal neurogenesis (AHN). Disrupting this process can lead to mood disorders like depression and increase the risk of memory problems. This sets the perfect stage for dementia to start rearing its ugly head.

Scientists have also identified another process that plays a role in the development of dementia. This one has to do with the brain’s immune system which few people are even aware of. There are cells within the brain called microglia that protect and cleanse it. However, when these cells become overactive, they can cause inflammation and damage.

This inflammation is common in both depression and neurodegenerative diseases like Alzheimer’s. In simple terms, when the brain can’t grow new cells and is constantly battling inflammation, it becomes more vulnerable to both depression and dementia.

This is where psychedelics like psilocybin are showing promise. Early research suggests that psilocybin could help the brain grow new cells and reduce harmful inflammation. By addressing these two critical problems—poor neurogenesis and chronic brain inflammation—psilocybin could potentially lower the risk of dementia, especially in people struggling with depression.

In this article, we’re going to review the conclusions of a narrative review called, Psilocybin for dementia prevention? The potential role of psilocybin to alter mechanisms associated with major depression and neurodegenerative diseases, and what it could mean for the millions of people suffering from dementia.

How the Brain Creates New Neurons (Neurogenesis)

Before we get into psilocybin’s potential to treat dementia and other neurodegenerative conditions, it’s important to understand the mechanisms through which the brain can change itself. The brain can be a fertile garden when it’s treated right and given the right nutrients. When we say nutrients, it doesn’t necessarily mean food too. Exercise, healthy relationships, and adequate sleep are just a few things that can lead to a healthier brain.

When this garden is healthy and thriving, it supports clear thinking and emotional balance. But when it slows down or becomes overrun with weeds (like inflammation), it can lead to problems like depression and memory loss.

When the AHN process mentioned in the previous section slows down and microglia become overactive, it creates the perfect storm for mental health issues and cognitive decline. This combination can worsen depression and may eventually contribute to neurodegenerative diseases like dementia.

Excitingly, early studies suggest that psilocybin might help by encouraging the growth of new neurons and calming overactive microglia. This means psilocybin could potentially repair the brain’s “garden,” making it more resilient against depression and dementia.

In the next section, we’ll explore how psilocybin directly impacts the brain and why it holds so much promise for mental health and cognitive protection.

Psilocybin's Role in Brain Health

Let’s draw the link between psilocybin and its potential to treat dementia. The factors that we identified as leading causes of dementia are counteracted by the effects of psychedelics like psilocybin. Many studies have demonstrated that psychedelics act as “psychoplastogens” meaning that they promote brain plasticity—the brain’s ability to adapt, grow, and form new connections. The image below shows how the depressed or dementia riddled brain’s neurons compare to those of a healthy person’s brain. Psychedelics restore what are called dendritic branches and spines to a healthy state.

Dendritic spines are tiny, branch-like structures on neurons that are essential for receiving and processing information from other brain cells. These spines play several vital roles:

Receiving Synaptic Inputs: They increase the surface area of neurons, allowing them to form more connections with other brain cells.

Signal Integration: Help process and combine signals from various sources, which is essential for learning and memory.

Plasticity and Adaptation: Their structure is dynamic, meaning they can change in response to new information or experiences, supporting learning and memory.

Signal Amplification: They can strengthen important signals, particularly those that reinforce long-term memory.

Maintaining Synaptic Health: Spines house important neurotransmitter receptors and signaling molecules necessary for brain communication.

Damage or loss of these spines can disrupt communication between brain cells, contributing to cognitive decline and mood disorders. It’s by promoting growth in these spines that psilocybin can help alleviate the symptoms of dementia.

This process has been observed in animal studies where psilocybin was shown to stimulate the growth of new neurons in the hippocampus. In one particular study involving mice, a single dose of psilocybin increased the number of new brain cells and improved fear extinction. The fear response is an interesting point because it suggests that psilocybin could help the brain recover from traumatic experiences (Du et al., 2023). From a psychiatric perspective, this could become a powerful tool for treating those who suffer from trauma and post traumatic stress disorder.

The other key factor contributing to dementia and depression that we touched on was the overactive microglia. Luckily, psilocybin is showing promise in toning done that hyperactivity as well. In human studies, psilocybin lowered levels of inflammatory markers like TNF-α and IL-6, which are linked to depression and neurodegenerative diseases (Mason et al., 2023). By calming this overactivity and consequently the inflammation that would result from it, psilocybin might protect the brain from long-term damage.

By promoting neuron growth and reducing inflammation, psilocybin addresses two of the biggest factors that contribute to both depression and dementia. This dual action makes it an exciting candidate for further research in preventing and possibly slowing the progression of dementia.

Additional Studies

Animal studies have shown that mid-dose psilocybin enhances learning and memory through 5HT2A receptor activation, promoting neuroplasticity. Interestingly, lower doses stimulate hippocampal neurogenesis, while higher doses may inhibit this process. Observational studies in hu+mans have reported sustained improvements in creativity and attention over several weeks of microdosing.

High-dose studies in patients with depression and anxiety have demonstrated long-lasting mood improvements and meaningful psychological experiences, highlighting the profound impact psychedelics can have on mental health. Functional MRI studies further support this, showing enhanced connectivity between brain regions responsible for emotion and cognition following psilocybin administration.

We’ve touched on dementia and depression, but another neurodegenerative disease affecting millions is Alzheimer’s. Unsurprisingly, psychedelics have shown promise in treating Alzheimer’s as well. Like dementia, Alzheimer’s is partly a result of reduced cognitive

Furthermore, psychedelics’ anti-inflammatory properties, driven by 5HT2A receptor activation, offer neuroprotective benefits by mitigating oxidative stress and supporting mitochondrial function. These effects could be instrumental in slowing cognitive decline and enhancing brain resilience.

Case Study: The Patient Experience in Psilocybin Research

Let’s explore another case study looking to assess psilocybin’s effectiveness in treating neurodegenerative diseases. Dr. Garcia-Romeu’s from John Hopkins University’s Center for Psychedelic and Consciousness Research undertook a study to gain insight into how psilocybin therapy could benefit individuals with Mild Cognitive Impairment (MCI) or early-stage Alzheimer’s and related dementias (ADRDs). Participants underwent a rigorous six-hour screening, including a physical exam, blood tests, an EKG, and comprehensive mental health assessments. Baseline measurements of anxiety, depression, and cognitive function were also recorded.

The preparation phase took place over a span of three to four weeks, involving weekly counseling sessions with study facilitators. These sessions were focused on understanding the participant’s life experiences, traumas, relationships, and spiritual beliefs. You might notice that this was quite a long preparation phase, but as demonstrated in countless other studies, establishing intentions prior to a psychedelic experience can have a significant impact on the effectiveness of the experience.

Participants then engage in dosing sessions, starting with a 15mg psilocybin capsule under close supervision. If well-tolerated, a second session with a 25mg dose follows. Experiences vary widely, from vivid sensory perceptions and autobiographical memories to profound emotional and spiritual insights. Facilitators provide continuous support, helping participants navigate challenging emotions and reinforcing their sense of safety.

The final integration phase helps participants process their psychedelic experiences and apply insights to their daily lives. Over two to three months, participants are closely monitored, with follow-up assessments extending six months to evaluate psychosocial symptoms and overall quality of life.

These studies are ongoing at Johns Hopkins, but the results have been promising so far with over 80% of patients reported increased life satisfaction. One thing that we at Mind Mend like about the design of this study is that it puts a lot of emphasis on the key stages of psychedelic use:

Preparation
Journey
Integration

Regardless of what the goal is with psychedelic use, following a proper protocol like this is always a good idea. If you want to learn more about the ins and outs of proper and responsible psychedelic use, we encourage you to check out our microdosing and macrodosing guides for psilocybin.

The Path Forward

Decades of unsuccessful treatments for dementia highlight an urgent need for innovative therapies. Psychedelics, with their ability to enhance neuronal connectivity, stimulate neurogenesis, restore brain plasticity, and reduce inflammation, offer a promising therapeutic avenue. Evidence from animal models and human studies underscores their neuroprotective and cognitive-enhancing potential, particularly for neurodegenerative diseases like Alzheimer’s.

There’s a lot still to be determined and fleshed out though. For example, one key aspect that’s still up for debate is the ideal dosing strategy—whether micro or macro. Adding to that, frequency of dosing is another factor since some studies have shown that some patients can see dramatic improvements after a single dose while others require several doses over months to experience similar improvements. Rigorous, long-term clinical studies will be essential to evaluate the safety, efficacy, and lasting impact of psychedelics on cognitive function in both healthy and cognitively impaired populations.

We’re standing at the threshold of transformative advancements in brain health with this renewed interest in psychedelics. With dedicated research, these compounds may revolutionize how we approach cognitive decline, offering hope for improved cognition, mood, and overall mental well-being.