Psilocybin and the Default Mode Network

You may have heard people speaking about the DMN in relation to psychedelic substances like psilocybin. But what does DMN mean, and why is it relevant to psychedelic retreats like Synthesis?

What is the Default Mode Network (DMN)?

DMN stands for Default Mode Network. It’s the name given to a network in the brain that has been shown to be crucial in normal, everyday consciousness.

The DMN is a loose connection of different brain areas and neuron groups, that communicate together to help us function in the world. High activity in the DMN is linked to mental processes such as our awareness of ourselves (roughly the same as the ego), social thinking (i.e. understanding what other people are feeling), and thinking about the past or future (see the original research here).

The DMN is at its lowest levels of activity when you are focussed on specific tasks such as trying to keep your vision on a moving object, or solving puzzles; activities that don’t involve autobiographical memory or self-reflection (see this research here). At times like these, another brain network called the Task Positive Network, or TPN, will be particularly active.

What is the relationship between the DMN and the Task Positive Network (TPN)?

The Task Positive Network, or TPN, is another brain network. It could be considered somewhat opposite to the DMN – when the DMN is active, the TPN is less active, and vice-versa. When people are focussed on attention-demanding tasks, typically their TPN will be more active, and DMN less active. When people are allowing their thoughts to wander, the DMN will typically be more active, and the TPN less active.

This is known as TPN/DMN synchronization, and it is disrupted in people with conditions like ADHD, who experience unusual difficulties in attention – or people with conditions like depression, who struggle to free themselves of negative thoughts. See the research on ADHD here and the research on depression here01103-6/fulltext).

The Default Mode Network and mental health

The DMN has been linked to several different mental health conditions. Both its hyperactivity and disrupted activity can contribute to symptoms. Here is what we know so far about the involvement of the DNM in various mental health conditions.

The DMN and depression

Hyperactivity in certain regions of the DMN has been correlated with excessive rumination, in people with severe depression. In other words, when parts of the DMN are overactive, it can contribute to forms of self-reflection that are inaccurate or excessively negative. These modes of thinking are symptomatic of depression.

Lower activity in other regions of the DMN has been correlated with overgeneral autobiographical memory (OGM), another symptom of depression. OGM is when an individual is more likely to remember general events rather than specific ones when prompted. It is also a symptom of PTSD and bipolar disorder, as well as depression.

It is clear that changes in the activity of specific parts of the DMN can both significantly contribute to, or reduce depressive symptoms.

The DMN and PTSD

Severe PTSD has been linked to lower overall connectivity within the DMN, but also a host of subtle changes in specific parts of the DMN; including the fact that some areas are much more active (you can read this research here).

The DMN and attention deficit hyperactivity disorder (ADHD)

Decreased connectivity in the DMN has been observed in people with ADHD (read the original study here). This has been linked to the attention-related deficits in people with ADHD. These typically result in the inability to control socially unacceptable behavior and the inability to concentrate on self-reflection for extended periods.

The DMN and autism

Similarly to ADHD, autism has been linked with decreased DMN connectivity (the original research is here). This could be connected to the difficulty that autistic people typically have in understanding social cues, seeing things from other people’s perspectives, and understanding their own emotional responses.

The DMN and chronic pain

Patients with chronic pain who are more likely to ruminate about their pain are also more likely to have higher DMN connectivity. This rumination could be linked to the severity of the patients’ experience of chronic pain (see the research here).

The DMN and schizophrenia

It has been shown that the DMN is more active in people with schizophrenia when they are trying to focus on attention-demanding tasks (this research can be seen here). Usually, the DMN would reduce in activity as the TPN takes over for these cognitive processes.

Recent research suggests that the failure of the DMN to be suppressed during attention-demanding tasks in schizophrenic people is linked to other cognitive deficits associated with the condition. If people with schizophrenia are suffering from cognitive symptoms such as paranoia, they are also more likely to have higher DMN activity when trying to complete focussed tasks (the original research is here).

How do you turn off the DMN?

Various different behaviors and techniques can be used to reduce the power of the DMN over your cognition.

Meditation has been shown to reduce DMN connectivity in people who have been practicing for many years (this research is here). This would make sense, considering most forms of directed meditation aim to reduce the influence of the self over resting thoughts. However, some forms of meditation (such as transcendental meditation) can increase the activation of the DMN – again, this makes sense as these forms of meditation do not attempt to reduce thoughts of the self (research on meditation can be read here).

Acupuncture has been shown to lower the activity of the DMN, possibly because the pain stimulus distracts the mind from thoughts of the past, future, and self. Read about this research here.

Some antidepressants and some forms of therapy have been shown to reduce the activity of the DMN in people with mental health conditions (read this research here).

Psychedelics are possibly the most immediate and profound way to reduce the control of the DMN over the mind. Neuroimaging studies have consistently shown that psychedelics like LSD and psilocybin significantly reduce DMN connectivity and that this correlates with the experiencing of ego-dissolution (or losing the sense of self). This “resetting” of the DMN could be linked to the antidepressant effects of psilocybin. This research can be found here and here.

Good to know: Synthesis does not currently cater to applicants with preexisting mental health diagnoses. However, if you wish to explore the possibilities of psychedelic-assisted treatments, which are currently being investigated for various conditions, you can apply to take part in a clinical trial.

How does psilocybin work on the DMN?

Psilocybin has a significant effect on the DMN. When you ingest psilocybin, either in the form of magic mushrooms or magic truffles, the usual connections in the DMN very rapidly dissolve and your brain becomes free of the control of the DMN (read this research here).

The rapid loss of DMN control has been correlated with the feelings of ego-dissolution that people can experience after taking a psychedelic substance. Ego-dissolution is defined as the loss of a sense of self that occurs during a psychedelic experience – and which helps people experience the boundaries between themselves and the world disappearing. Temporary ego-loss is considered to be the most profound effect of psychedelics, and the one that can induce the most powerful personal transformations.

Additionally, psilocybin releasing the control of the DMN during a trip means you are less likely to ruminate on the past – at least for the duration of your experience. This research is here.

Interestingly, researchers have found that although the DMN is reduced in power during the psychedelic experience, it comes back even stronger in the weeks following the experience. Scientists postulate that this “resetting” of the DMN could be beneficial for people suffering from depression, as reductions in depression scores following psilocybin treatment are directly correlated with the specific way in which the DMN puts itself back together.

So the release and “resetting” of the brain’s control mechanisms induced by a psilocybin experience is likely to be related to the profound healing and transformational benefits that psilocybin can produce.

The Synthesis retreat makes the most of psilocybin’s effects on the DMN, by helping participants explore the freedom from egoic control in a safe, comfortable, and guided environment.

Sign up to Synthesis here!