Kim P. C. Kuypers

Kim P. C. Kuypers
Maastricht University | UM · Department of Neuropsychology and Psychopharmacology

PhD

About

140
Publications
68,817
Reads
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3,166
Citations
Citations since 2017
74 Research Items
2336 Citations
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Introduction
My main topics of interest are MDMA and psychedelics, and their effects on (social) cognition, creativity, hormones, and underlying brain mechanisms. Together with a team of researchers, we conduct psychedelic research. This research includes 3 pillars: (1) placebo-controlled experimental studies focused at understanding the underlying neurobiology of acute and longer-term effects of psychedelic substances on empathy and flexible cognition (2) naturalistic studies focused on understanding the acute and longer-term effects of psychedelics on well-being, empathy and flexible cognition in a naturalistic setting (3) survey studies focused on understanding amongst other motives of drug use
Additional affiliations
November 2015 - present
Maastricht University
Position
  • Coordinator
Description
  • Course: 'Hormones, the Brain and Behavior, an introduction to behavioral neuroendocrinology', Elective course for 3rd year psychology students and mental health students at Maastricht Universtity
January 2014 - present
Maastricht University
Position
  • Coordinator
Description
  • Course: 'Discover Psychology', 'Drugs and the Brain' for 1st year bachelor students psychology at FPN, Maastricht University
March 2013 - present
Maastricht University
Position
  • Professor (Assistant)
Description
  • Research into the behavioral effects of psychedelic drugs and novel psychoactive substances

Publications

Publications (140)
Preprint
Full-text available
Patients characterized by stress-related disorders such as depression display elevated circulating concentrations of pro-inflammatory cytokines and a hyperactive HPA axis. Psychedelics are demonstrating promising results in treatment of such disorders, however the mechanisms of their therapeutic effects are still unknown. To date the evidence of ac...
Article
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Rationale Delta-9-tetrahydrocannabinol (THC), an active component of cannabis, can cause anxiety in some users during intoxication. Cannabidiol (CBD), another constituent of cannabis, has anxiolytic properties suggesting that cannabis products containing CBD in addition to THC may produce less anxiety than THC-only products. Findings to date around...
Article
ADHD in adulthood is often overlooked, which negatively affects the individual’s well-being. First-line pharmacological interventions are effective in many ADHD patients, relieving symptoms rapidly. However, there seems to be a proportion of individuals who discontinue, or fail to respond to these treatments. For these individuals, alternative trea...
Article
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Although several studies and reports have shown the potential analgesic use of serotonergic psychedelics in cancer pain, phantom limb pain and cluster headache, evidence supporting their use for chronic pain is still limited. The past years have seen a considerable renewal of interest toward the therapeutic use of these compounds for mood disorders...
Article
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Anxiety disorders are the most common type of psychiatric disorders among Western countries. Evidence-based treatment modalities including pharmacological and cognitive-behavioral therapy result in deficient treatment responses. Historical and recent research suggests psychedelic drugs may be efficacious in alleviating anxiety-related symptoms amon...
Article
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Psilocybin microdosing involves repeated self-administration of mushrooms containing psilocybin at doses small enough to not impact regular functioning. Microdose practices are diverse and include combining psilocybin with substances such as lion's mane mushrooms (Hericium erinaceus; HE) and niacin (vitamin-B3). Public uptake of microdosing has out...
Article
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Modern clinical research on psychedelics is generating interesting outcomes in a wide array of clinical conditions when psychedelic-assisted psychotherapy is delivered to appropriately screened participants and in controlled settings. Still, a number of patients relapse or are less responsive to such treatments. Individual and contextual factors (i...
Article
Background Current first-line treatment for social anxiety disorder (SAD), one of the most prevalent anxiety disorders, is limited in its efficacy. Hence, novel treatment approaches are urgently needed. The current review suggests a combination of meditation-based interventions and the administration of a psychedelic as a future alternative treatme...
Article
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Background Synthetic cannabinoids (SCs) are the largest class of novel psychoactive substances (NPS) and are associated with an increased risk of overdosing and adverse events such as psychosis. JWH-018 is one of the earliest SCs and still widely available in large parts of the world. Controlled studies to assess the safety and behavioural profiles...
Article
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Due to differences in potency, efficacy, and affinity for CB1 receptors, similarities and differences in psychoactive effect profiles of natural cannabis and synthetic cannabinoids (SCs) cannot reliably be derived from equipotent dose comparisons. Instead, the current study proposes to compare the intrinsic psychoactive effects of natural cannabis...
Article
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Background Resistance training (RT) can offer beneficial physiological and psychological effects. The regular continuation of this exercise can be accomplished by improving the recovery and mood after a workout. Frequency-specific microcurrent (microstimulation) might offer a solution here as it has been shown to improve physical injuries, mood sta...
Preprint
Full-text available
Anxiety disorders are the most common type of psychiatric disorders among Western countries. Evidence-based treatment modalities including pharmacological and cognitive-behavioral therapy result in relatively low response rates (average range: 51 - 58%). Historical and recent research suggests psychedelic drugs may be efficacious in alleviating anx...
Article
Full-text available
Research has shown that patients with a social anxiety disorder (SAD) show social performance deficits. These deficits are a maintaining factor in SAD, as mending social behavior improves interpersonal judgments and reduces social anxiety. Thus finding ways to enhance social behavior is evidently of importance in the treatment of SAD. This double-b...
Article
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The use of psychedelic substances at sub-sensorium ‘ microdoses’, has gained popular academic interest for reported positive effects on wellness and cognition. The present study describes microdosing practices, motivations and mental health among a sample of self-selected microdosers ( n = 4050) and non-microdosers ( n = 4653) via a mobile applicat...
Article
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Background: Naturalistic and placebo-controlled studies have suggested that ayahuasca, a traditional Amazonian beverage, could be helpful in the treatment of psychopathologies like depression and anxiety disorders by changing otherwise disturbed cognitive and emotional processes. To better understand its full therapeutic potential, one way is to st...
Article
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Clinical studies suggest the therapeutic potential of psychedelics, including ayahuasca, DMT, psilocybin, and LSD, in stress-related disorders. These substances induce cognitive, antidepressant, anxiolytic, and antiaddictive effects suggested to arise from biological changes similar to conventional antidepressants or the rapid-acting substance keta...
Article
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Ayahuasca is a plant concoction containing N,N-dimethyltryptamine (DMT) and certain β-carboline alkaloids from South America. Previous research in naturalistic settings has suggested that ingestion of ayahuasca can improve mental health and well-being; however, these studies were not placebo controlled and did not control for the possibility of exp...
Article
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Introduction Kratom (Mitragyna speciosa) is a tropical plant traditionally used as an ethnomedicinal remedy for several conditions in South East Asia. Despite the increased interest in its therapeutical benefits in Western countries, little scientific evidence is available to support such claims, and existing data remain limited to kratom's chronic...
Chapter
Microdosing psychedelics, the repeated use of small doses of substances such as psilocybin and lysergic acid diethylamide, has gained popular and scientific attention in recent years. While some users claim microdosing psychedelics has therapeutic value, to date only a handful of (placebo-controlled) experimental studies in human volunteers have be...
Article
Full-text available
Creativity is an essential cognitive ability linked to all areas of our everyday functioning. Thus, finding a way to enhance it is of broad interest. A large number of anecdotal reports suggest that the consumption of psychedelic drugs can enhance creative thinking; however, scientific evidence is lacking. Following a double-blind, placebo-controll...
Chapter
There is increasing evidence of the potential therapeutic value of the psychedelic brew ayahuasca for disorders like depression, PTSD, and anxiety. While the focus has been on ayahuasca’s capacity to reduce symptoms of these disorders, including enhancing mood state and well-being, little attention has been paid to the (higher-order) cognitive proc...
Article
Kratom (Mitragyna speciosa) is a tree native to Southeast Asia with long history of traditional medicinal use. The aim of this study was to investigate the nature of self-reported exported experiences as shared on YouTube™ videos. A total of 500 videos with 19,478,180 views and 134, 863 comments emerged from the data scrape extracted via the YouTub...
Article
Background Smoking mixtures containing synthetic cannabinoids (SCs) have become very popular over the last years but pose a serious risk for public health. Limited knowledge is, however, available regarding the acute effects of SCs on cognition and psychomotor performance. Earlier we demonstrated signs of impairment in healthy volunteers after admi...
Article
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Parkinson's disease (PD) is a prevalent neurodegenerative disease for which only symptomatic treatments, mainly focused on motor symptoms. In contrast, conventional pharmacological treatments do not address cognitive impairment and emotional dysfunction. Together with potential treatment side effects, these can cause distress, lower the quality of...
Article
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There is a popular interest in microdosing with psychedelics such as LSD. This practice of using one-tenth of a full psychedelic dose according to a specific dosing schedule, anecdotally enhances mood and performance. Nonetheless, controlled research on the efficacy of microdosing is scarce. The main objective of the present dose-finding study was...
Article
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"Microdoses" of lysergic acid diethylamide (LSD) are used recreationally to enhance mood and cognition. Increasing interest has also been seen in developing LSD into a medication. Therefore, we performed a pharmacokinetic-pharmacodynamic study using very low doses of LSD. Single doses of LSD base (5, 10, and 20 µg) and placebo were administered in...
Article
Despite preclinical evidence for psychedelic-induced neuroplasticity, confirmation in humans is grossly lacking. Given the increased interest in using low doses of psychedelics for psychiatric indications, and the importance of neuroplasticity in the therapeutic response, this placebo-controlled within-subject study investigated the effect of singl...
Article
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Background Lysergic acid diethylamide (LSD) is an ergot alkaloid derivative with psychedelic properties that has been implicated in the management of persistent pain. Clinical studies in the 1960s and 1970s have demonstrated profound analgesic effects of full doses of LSD in terminally ill patients, but this line of research evaporated after LSD wa...
Article
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Microdosing psychedelics is the repeated use of small doses of, for example, lysergic acid diethylamide (LSD) and psilocybin, typically for a few weeks. Despite the popular and scientific attention in recent years, and claims by users that it has therapeutic value in affective disorders like depression, little scientific knowledge is available to b...
Article
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There is growing interest in the therapeutic utility of psychedelic substances, like psilocybin, for disorders characterized by distortions of the self-experience, like depression. Accumulating preclinical evidence emphasizes the role of the glutamate system in the acute action of the drug on brain and behavior; however this has never been tested i...
Article
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Depression is a major public health problem that affects approximately 4.4% of the global population. Since conventional pharmacotherapies and psychotherapies are only partially effective, as demonstrated by the number of patients failing to achieve remission, alternative treatments are needed. Mindfulness meditation (MM) and psilocybin represent t...
Article
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Background: It has been suggested that the outcome of the psychedelic experience is dependent on set and setting. While scientific research into the therapeutic potential of psychedelics is growing, it is clear that in clinical populations an optimal set and setting will not always be attainable. It was aimed to assess under which emotional and env...
Article
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Mephedrone (4-MMC, mephedrone) is a synthetic cathinone derivative included in the class of new psychoactive substances. It is commonly used simultaneously with alcohol (ethanol). The aim of the present study was to evaluate the interactions on subjective, cardiovascular and hormone effects and pharmacokinetics between mephedrone and alcohol in hum...
Article
Background: The repeated use of small doses of psychedelics such as psilocybin and lsd over a period of time (microdosing, md) has gained popularity and scientific attention in recent years. Retrospective reports from users suggest clinical potential. AIM: To answer the question whether md with psychedelics could theoretically provide symptom reli...
Article
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Background: There is a growing interest in the use of psychedelic substances for health related purposes, including symptom relief for disorders like anxiety, depression, and pain. Although the focus of recent clinical trials has been on high doses of these substances, anecdotal evidence suggests that low (micro) doses are also effective, and may b...
Article
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Background 5-methoxy-N,N-dimethyltryptamine (hereinafter referred to as 5-MeO-DMT) is a psychedelic substance found in the secretion from the parotoid glands of the Bufo alvarius toad. Inhalation of vapor from toad secretion containing 5-MeO-DMT has become popular in naturalistic settings as a treatment of mental health problems or as a means for s...
Article
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Novel psychoactive substances (NPS) are compounds designed to mimic the effects of existing recreational drugs (classical psychoactive substances [CPS]), while eluding established legal frameworks. Little is known about their effects and potential harms, rendering the increasing number of NPS a challenge to policy makers and researchers alike. Quan...
Article
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Background In the past few years, the issue of ‘microdosing’ psychedelics has been openly discussed in the public arena where claims have been made about their positive effect on mood state and cognitive processes such as concentration. However, there are very few scientific studies that have specifically addressed this issue, and there is no agree...
Article
Anecdotal evidence suggests that cocaine use will help overcome creative 'blocks' by enhancing flexible thinking. Given that cocaine is likely to enhance dopamine (DA) levels, which in turn are positively associated with divergent thinking (DT); is a possibility that is tested in the present study. Furthermore, the impact of cocaine is tested on co...
Article
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Background: Microdosing with psychedelics has gained considerable media attention where it is portrayed as a performance enhancer, especially popular on the work floor. While reports are in general positive, scientific evidence about potential negative effects is lacking aside from the prevalence and motives for use. The present study addressed th...
Article
Introduction Each year, synthetic drugs are occurring in high numbers in the illicit drug market. But data on their pharmacology and toxicology are scarcely available. Therefore, a controlled study was performed to evaluate pharmacokinetic parameters of 4‐fluoroamphetamine (4FA) in humans and to compare it with its effects. Methods Twelve subjects...
Article
Introduction: Synthetic cannabinoid mixtures have been easily accessible for years, leading to the belief that these products were natural and harmless, which contributed to their popularity. Nevertheless, there are many reports of users ending up in hospital due to severe side effects such as tachycardia, aggression, and psychosis. Controlled stud...
Article
Full-text available
Creative thinking and empathy are crucial for everyday interactions and subjective well-being. This is emphasized by studies showing a reduction in these skills in populations where social interaction and subjective well-being are significantly compromised (e.g., depression). Anecdotal reports and recent studies suggest that a single administration...
Article
This study summarizes the literature about alcohol- and drug-related public violence in Europe. The proportion of all public violent incidents linked to alcohol was about 50 percent in the UK and ranged from 26 percent to 43 percent in Germany, Austria and the Netherlands. Public violence related to drugs is much lower (1.5–18.0 percent). Relativel...
Article
Full-text available
Psychedelic substances have regained interest as therapeutic agents in the treatment of stress-related disorders. The effects seem to be of persisting nature even after a single dose. Also in lower than ‘regular’ recreational doses, so-called micro-doses, without the typical effects on consciousness, users report beneficial effects on cognitive pro...
Article
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The phenethylamine 4-fluoroamphetamine (4-FA) is a so-called novel psychoactive substance with a chemical structure resembling that of amphetamine and MDMA. Since 4-FA users report their subjective experience ranges between the effects induced by amphetamine and MDMA, and it is known that both substances can produce an altered state of consciousnes...
Article
Received: February 22, 2018 Accepted: November 05, 2018 Published online: January 04, 2019 Issue release date: March 2019
Article
Full-text available
Rationale Ayahuasca is a psychotropic plant tea from South America used for religious purposes by indigenous people of the Amazon. Increasing evidence indicates that ayahuasca may have therapeutic potential in the treatment of mental health disorders and can enhance mindfulness-related capacities. Most research so far has focused on acute and sub-a...
Article
Full-text available
Background: New psychoactive substances (NPS) are chemical analogues designed to mimic the effects of various classic recreational drugs of abuse including MDMA, LSD, and cannabis. NPS use is associated with concern about the acute and longer-term effects particular substances might have, with abuse and addiction as potential consequences. Impulsi...
Article
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Availability of novel psychoactive substances (NPS) exponentially increased over the last years. Risk evaluations of NPS are hampered by the lack of pharmacological studies in humans on health parameters. The aim of the present study was to evaluate safety and neurocognitive function of healthy volunteers (N = 12) who received single doses of 100 a...
Article
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Background: Prospective memory is the ability to recall intended actions or events at the right time or in the right context. While cannabis is known to impair prospective memory, the acute effect of cocaine is unknown. In addition, it is not clear whether changes in prospective memory represent specific alterations in memory processing or result...
Article
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Background: A substantial number of people worldwide suffer from mental health problems during their lifetime. First-line treatments are not effective for everybody. Recent studies suggest that psychedelic drugs have high therapeutic potential for a variety of mental disorders. Aims: This survey study aimed to assess the tendency of psychedelic us...
Article
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Rationale: Violence and drug use are significant public health challenges that are strongly linked. It is known that alcohol plays a major role in the causation of unnatural deaths and that stimulants like cocaine and amphetamine are often implicated in aggressive acts or violence. However, a clear causal relationship between these substances and...
Article
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Empathy has been typically studied by means of paradigms including static representations of socially relevant stimuli and it has been acknowledged that there is need for more ecologically valid, dynamic measures. The present study aimed to study implicit ('arousal') and explicit ('concern') emotional empathy in response to positive and negative em...
Article
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Background Preclinical data have suggested involvement of the endocannabinoid (eCB) system in MDMA-induced memory impairment. Clinical research has shown that blockade of the 5-HT2 receptor nulls memory impairment during MDMA intoxication. Interestingly, studies have demonstrated that the eCB and the 5-HT system interact. It was hypothesized that M...
Article
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Our creativity is challenged daily when facing new situations asking for novel solutions. Creativity, a multicomponent construct includes flexible divergent and rigid convergent thinking. Psychedelic drugs like psilocybin can enhance creativity and affect state of mind (mood, empathy, openness). Of note, flexible thinking is disturbed in psychopath...
Article
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Background: MDMA has been shown to induce feelings of sociability, a positive emotional bias and enhanced empathy. While previous research has used only visual emotional stimuli, communication entails more than that single dimension and it is known that auditory information is also crucial in this process. In addition, it is, however, unclear what...