Investigating the role of serotonin in visual orientation processing using an 'ecstasy' (MDMA)-based research model.
Clare Dickson, Raimondo Bruno, John Brown
Neuropsychobiology 2009 DOI: 10.1159/000253556 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 56 |
| Population | Ecstasy users, cannabis users, ecstasy plus cannabis users, and drug-naive controls with no recent amphetamine use |
| Topics | MDMA Serotonin |
| Key findings | Ecstasy users had a greater tilt aftereffect at 40 degrees adaptation compared to non-users, and the extent of ecstasy use was positively associated with aftereffect magnitude at 15, 30, and 40 degrees but not at 60 degrees, supporting a role for serotonin in visual orientation processing via lateral inhibition. |
Abstract
A growing body of evidence suggests that regular 'ecstasy' (3,4-methylenedioxymethamphetamine) use causes lasting changes to central serotonergic functioning in humans, including in the occipital lobe. Serotonin may play a role in visual orientation processing, mediated in the occipital lobe, via lateral inhibition. The tilt aftereffect is an illusion apparent following adaptation to stimuli angled 5-50 degrees from vertical and thought to be affected by lateral inhibition between occipital neurons. A recent study identified an enhanced tilt aftereffect among ecstasy users, but only in a subset that were recently abstinent from amphetamines. The current study examined the effects of ecstasy use, cannabis use and their interacting effect on the magnitude of the tilt aftereffect among participants with no recent history of amphetamine consumption. Eleven ecstasy users, 15 cannabis users, 15 ecstasy plus cannabis users and 15 drug-naïve controls were compared on the magnitude of the tilt aftereffect elicited following adaptation to stimuli angled 15, 30, 40 or 60 degrees from vertical. At a 40 degrees adaptation condition, ecstasy users had a greater magnitude of the tilt aftereffect compared to those that had not taken the drug. Additionally, the extent of ecstasy use was positively associated with the magnitude of the tilt aftereffect generated following 15, 30 and 40 degrees adaptation conditions, but not at 60 degrees. Given that lateral inhibition mediates the tilt aftereffect following adaptation to 5-50 degrees , the findings of a relationship between ecstasy use and tilt magnitude at the 15-40 degrees but not 60 degrees adaptation conditions support a role for serotonin in visual orientation processing via lateral inhibition.
Comparable studies
Other observational and cohort studies on MDMA, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Subjective Reports of the Effects of MDMA in a Clinical Setting Individuals who took MDMA in a clinical setting | 1986 | Observational study | |
| Memory impairment in abstinent MDMA ("Ecstasy") users Abstinent MDMA users | 1998 | Observational cohort | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| The Psychological and Physiological Effects of MDMA on Normal Volunteers Older, more educated, drug-experienced individuals | 1986 | Observational cohort | |
| Cognitive performance in recreational users of MDMA or 'ecstasy': evidence for memory deficits Young people who were regular or novice MDMA users, or non-users | 1998 | Observational cohort | n = 30 |
Citations in the library
Cited by 8
- Human psychobiology of MDMA or ‘Ecstasy’: an overview of 25 years of empirical research Human Psychopharmacology: Clinical and Experimental July 1, 2013
- Investigating the Mechanisms of Hallucinogen-Induced Visions Using 3,4-Methylenedioxyamphetamine (MDA): A Randomized Controlled Trial in Humans PLoS One December 2, 2010
- Visuospatial working memory impairment in current and previous ecstasy/polydrug users Human Psychopharmacology Clinical and Experimental June 1, 2011
- Editorial: Preface and Overview Second International MDMA ‘Ecstasy’ Conference in Australasia: Monash University, Melbourne, Australia The Open Addiction Journal March 29, 2011
- The Role of Serotonin in Low Level Visual Processes, as Revealed by Using an “Ecstasy” (MDMA)-Based Research Model The Open Addiction Journal March 29, 2011
and 3 more in the library
Cites 4
- Positron emission tomographic evidence of toxic effect of MDMA (“Ecstasy”) on brain serotonin neurons in human beings The Lancet October 1, 1998
- Reorganization of ascending 5-HT axon projections in animals previously exposed to the recreational drug (+/-)3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") Journal of Neuroscience August 1, 1995
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- The pharmacology and clinical pharmacology of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"). Pharmacological Reviews September 2003