What first captured my curiosity about the relationship between psychedelics and intelligence was an interesting correlation found with psychedelics and openness to experience. It turns out, psilocybin produced long-term increases in the personality trait known as openness to experience (MacLean, Johnson, & Griffiths 2011). Interestingly, out of all the personality traits studied in the five-factor model for personality, it is openness to experience that is most strongly linked to intelligence (Ashton, Lee, Vernon, & Jang 2000). More specifically, crystallized intelligence, although there is a small correlation to fluid intelligence as well. Openness to experience is a necessary quality for making the choice to engage in a more diverse range of experiences, and so you will build a larger library of experiences and notice more patterns in the world because you have actually observed more of the world in general. This could also provide behavioral changes that lead to self-stimulating of one’s intellect, a sort of constant training of your mind due to being more willing to engage in potentially challenging unknowns in the world, confronting novelty, which should aide in learning of new information. Beyond this, a possible mechanism for cognitive disruption is explored as a new study has found psychedelics to attenuate this mechanism which is involved in various forms of cognitive dysfunction such as age-related cognitive decline, stress induced cognitive impairment, depression related symptoms, and alcohol-induced cognitive impairment.
So is there anything to this?
Do psychedelics increase intelligence?
Psychedelics appear to help with PTSD (Feduccia & Mithoefer 2018). PTSD has been associated negatively with IQ (Saltzman, Weems, & Carrion 2006), something which I have explored thoroughly in my post Dynorphin Theory.
Dynorphin may help to explain the reduced IQ observed in PTSD. PTSD is associated with dynorphin (Bailey, Cordell, Sobin, & Neumeister 2013). Stress and depression have also been linked to dynorphin (Knoll, & Carlezon Jr. 2010).
The research linked here has noted that premorbid IQ being lower might make PTSD worse, but even if lower premorbid IQ were found, this may be due to early life stress or prior trauma limiting IQ and even promoting more severe stress reactions in adulthood. It was found that exposure to domestic violence suppressed IQ (Koenen, Moffitt, Caspi et al 2003) and recently traumatized individuals showed cognitive impairment (Brandes, Ben-Schachar, Gilboa et al 2002). Prior trauma is a risk factor for experiencing further trauma. So it seems likely that prior trauma may be at play here with premorbid IQ scores.
A study on cops found that their openness to experience was reduced after experiencing a traumatic event (Leigh Wills, & Schuldberg 2016), which is significant because openness to experience is the only Big 5 trait linked to intelligence (Schretlen, van der Hulst, Pearlson, & Gordon 2010). I’ve explained before that negative experiences seem to reduce openness in a way that becomes obvious in context. Imagine that you experience an abusive relationship. You will become more aversive towards potential abusive relationships, which fall under the umbrella of “relationships”. You may become less willing to expose your vulnerable side in relationships and essentially this is one of the many issues with PTSD, an unwillingness to be vulnerable, to take risks. It’s really worth reading the full post on this concept. The relevance here is that openness may be a promoter for engagement with novel (and potentially risky/unknown) experiences. Novel experiences promote learning because these are the very situations needing to be learned (you don’t learn the already learned stuff).
Dynorphin mediates alcohol-related spatial learning and memory impairment (Kuzmin, Chefer, Bazov et al 2013). This occurs by disrupting glutamate neurotransmission in the hippocampus. Another study found stress-induced learning and memory impairment was mediated by dynorphin (Carey, Lyons, Shay et al 2009). This one is interesting because it is not limited to spatial cognition. Occlusal disharmony, a jaw problem that can cause neck stiffness and psychiatric depression, was shown to cause memory and learning impairments mediated by dynorphin activity in the amygdala (Yamada, Ono, Kubo et al 2013). It may be that pain aversion is mediated by dynorphin as well (Massaly, Copits, Wilson-Poe et al 2019), which would explain this effect of the occlusal disharmony on learning and memory. Stress was negatively correlated to academic performance in high IQ students (Malik & Balda 2006). There is also research showing up to 14 points IQ reduction during periods of scarcity and stress (Mullainathan 2014). There is also evidence that age-related cognitive decline involves dynorphin as well (Ménard, Herzog, Schwarzer, & Quirion 2014).
Dynorphin is known to impair plasticity in the hippocampus (Wagner, Terman & Chavkin 1993) and psychedelics have been shown to induce plasticity (Ly, Greb, Cameron et al 2018) and neurogenesis (Catlow, Jalloh, & Sanchez-Ramos 2016).
Here’s where it gets interesting.
A study from 2019 found that psychedelics attenuate kappa-opioid receptor (KOR)-mediated depressant effects (Sakloth, Leggett, Moerke et al 2019). This could mean that psychedelics attenuate reduced plasticity induced by dynorphin, correcting glutamate neurotransmission, and restoring cognitive ability.
UPDATE: 8 months after this post, researchers posed this very same question! Can Psychedelic Drugs Attenuate Age-Related Changes
in Cognition and Affect? (Aday, Bloesch, & Davoli 2019). The arguments are mostly similar, referencing research on neuroplasticity.
This may also help explain the various problems that psychedelics are proposed to fix, such as addiction, depression, anxiety, and PTSD.
This is likely part of the mechanism for how psychedelics attenuate addiction rapidly. This study suggests that psychedelics do not attenuate the abuse potential of methamphetamine, but only the dynorphinergic problems of stimulant use. Psilocybin has been shown to ‘cure’ tobacco addiction with one dose in 80% of subjects (Johnson, Garcia-Romeu, Cosimano, & Griffiths 2014). This is exciting because another study found nicotine to upregulate dynorphin/kappa-opioid receptor (KOR) system (Tejeda, Natividad, Orfila et al 2012) and dynorphin has been proposed as a core element to models of addictions to many drugs (Shippenberg, Zapata, & Chefer 2007). The attenuation of KOR-mediated activity by psychedelics found in the 2019 study may reveal a core mechanism to this attenuation of addiction. I’ve explored the relationship between nicotine and dynorphin in more depth in my article Nicotine Disorder.
My understanding of addiction is as follows:
The research seems to indicate that dynorphin may mediate the experience of dysphoria in stress (Land, Bruchas, Lemos et al 2008), cannabis (Valverdre & Maldonado 2001), physical pain and injury (Massaly, Copits, Wilson-Poe et al 2019). So here we begin at trauma but it quickly becomes clear how suffering in general will trap your behavior into security-seeking and low openness to experience. The result? The drug of choice is the only secure space left after raising the threshold for suffering so high. No longer can you take uncomfortable risks or try new things.
“Traumatic experiences may reduce the range of experiences a person is willing to engage with when the expectation is that these experiences would be potentially negative or risky. Prior to the trauma, experiences would have been good-good-good and there isn’t a clear reason to be cautious if bad things don’t seem to happen. This unwillingness to engage in unpredictable and novel situations might lead to a decline in cognition simply due to cognitive neglect. It also seems to be the case that the more negative someone is feeling, the more they would desire a reward that is highly predictable because they care more about ending the suffering than they would about exploring new things. Suffering adds a dimension of motivating one towards seeking distraction, in which we must quell the pain and boredom is of less priority than security. So not only would dynorphin promote specific aversions in the case of PTSD, but it would also invoke general malaise that becomes a high priority issue, detracting from one’s curiosity and reprioritizing our behavioral biases towards security. In this case, people may favor their comfort foods, as opposed to trying a new food that is potentially dislikable. The disappointment of disliked novel food would only stack with the prior stressors and make things worse so it is good to ensure successful reward acquisition rather than take a risk. For those who’s lives are generally good, they will build a tolerance towards repetitious rewards and begin to desire something more fulfilling: novel rewards for which we have no tolerance built towards.
This may be the role dynorphin plays in addiction. The benefits of the drug become the most predictable reward that is capable of attenuating suffering. Alongside that, dynorphin is generally upregulated by elevated dopamine levels which are involved in most, if not all, addictive drugs. Eventually your willingness to seek rewards other than the drug shrink down as suffering becomes more ubiquitous.”
So in essence it could be that psychedelics would decrease cognitive issues mediated by dynorphin activity. Psychedelics would relieve the depressed state, enhance neurogenesis, enhance openness, and broaden access to previously inhibited memories that had reduced access due to dynorphin and thus expanding crystallized intelligence. In some sense dynorphin may function to sculpt relevance and priority in a way that reduces our choices and thoughts to simple compulsions and linear thinking.
Psychedelics may not necessarily boost you beyond your natural genetic cognitive limitations, but instead function to erase the limiting factors like compulsive neurotic ruminations and distracting concerns as well as abolish the state of hopelessness we acquire throughout our lives. I suspect that in a post-scarcity utopian society we would never experience the “fall back to reality” while dosed on psychedelic drugs but instead remain elated in that state. For children, their security that is provided by parents combined with their naivety about the nature of reality can act as a sort of post-scarcity utopian simulation. A care free existence before the ubiquitous background suffering that emanates from our dystopian capitalistic world kicks in and the ignorance of naivety fades into oblivion. Serotonin signals resource security which I have written about in Serotonism, which may provide some obscure level of evidence towards this notion about post-scarcity utopias and the psychedelic state.
In some sense dynorphin may signal how bad living circumstances are, where a pool of dynorphin is inhibiting the less powerful motivations. Dynorphin may inhibit the motivations that are considered wasteful to resources. The more survivalist the situation, the more you must reduce extraneous behaviors, limiting creativity and cognitive flexibility, thus Pavlovian states like addiction and PTSD become dominant. Imagine that there is pool of dynorphin liquid and motivations can become actions or at the very least considerations when they surface above the pool. More dynorphin means less and less considerations can be made, a loss of openness. With addiction we find excessive rewards to increase the volume of this dynorphin pool by upregulating it. With stimulants you are increasing all motivations, and many now surface above the dynorphin pool. But as you fail to reach goals and rewards are not granted, the pool rises to stop these failing motivations. When you stop the stimulant you are severely inhibited and depressed.
Each person and their individual lives had built up pools of dynorphin that inhibit their dreams and ambitions. Sometimes life changes but we are stuck with mentalities that source from troubled childhoods or poor living conditions in the past. For these people psychedelics can simulate a sudden surge of security that drains this pool of dynorphin. As the drug wears off the environmental circumstances bring the pool back up to match. But perhaps we can escape the childhood echoes that restrain our dreams, enhancing our proneness to becoming a dreamer again. To become hopeful, to see all the possibilities updated to our most current circumstance.
With this, maybe psychedelics can help us remove the blockades that our dystopian society pushes into our minds, so that we may someday experience some kind of true utopia.
. . .
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