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Garel N, Thibault Lévesque J, Sandra DA, Lessard-Wajcer J, Solomonova E, Lifshitz M, Richard-Devantoy S, Greenway KT. Imprinting: expanding the extra-pharmacological model of psychedelic drug action to incorporate delayed influences of sets and settings. Front Hum Neurosci 2023; 17:1200393. [PMID: 37533588 PMCID: PMC10390742 DOI: 10.3389/fnhum.2023.1200393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 06/22/2023] [Indexed: 08/04/2023] Open
Abstract
Background Psychedelic drug experiences are shaped by current-moment contextual factors, commonly categorized as internal (set) and external (setting). Potential influences of past environments, however, have received little attention. Aims To investigate how previous environmental stimuli shaped the experiences of patients receiving ketamine for treatment-resistant depression (TRD), and develop the concept of "imprinting" to account for such time-lagged effects across diverse hallucinogenic drugs. Methods Recordings of treatment sessions and phenomenological interviews from 26 participants of a clinical trial investigating serial intravenous ketamine infusions for TRD, conducted from January 2021 to August 2022, were retrospectively reviewed. A broad literature search was undertaken to identify potentially underrecognized examples of imprinting with both serotonergic and atypical psychedelics, as well as analogous cognitive processes and neural mechanisms. Results In naturalistic single-subject experiments of a 28-year-old female and a 34-year-old male, subjective ketamine experiences were significantly altered by varying exposures to particular forms of digital media in the days preceding treatments. Higher levels of media exposure reduced the mystical/emotional qualities of subsequent psychedelic ketamine experiences, overpowering standard intention-setting practices and altering therapeutic outcomes. Qualitative data from 24 additional patients yielded eight further spontaneous reports of past environmental exposures manifesting as visual hallucinations during ketamine experiences. We identified similar examples of imprinting with diverse psychoactive drugs in past publications, including in the first-ever report of ketamine in human subjects, as well as analogous processes known to underly dreaming. Conclusions/interpretation Past environmental exposures can significantly influence the phenomenology and therapeutic outcomes of psychedelic experiences, yet are underrecognized and understudied. To facilitate future research, we propose expanding the contextual model of psychedelic drug actions to incorporate imprinting, a novel concept that may aid clinicians, patients, and researchers to better understand psychedelic drug effects. Clinical trial registration ClinicalTrials.gov, identifier NCT04701866.
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Affiliation(s)
- Nicolas Garel
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| | | | - Dasha A. Sandra
- Department of Psychology, McGill University, Montreal, QC, Canada
| | | | - Elizaveta Solomonova
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- Neurophilosophy Lab, Department of Philosophy, McGill University, Montreal, QC, Canada
| | - Michael Lifshitz
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC, Canada
| | - Stéphane Richard-Devantoy
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, LaSalle, QC, Canada
| | - Kyle T. Greenway
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC, Canada
- Department of Medicine, Centre for Psychedelic Research, Imperial College London, London, United Kingdom
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Picard-Deland C, Allaire MA, Nielsen T. Postural balance in frequent lucid dreamers: a replication attempt. Sleep 2022; 45:6581922. [PMID: 35522289 PMCID: PMC9272189 DOI: 10.1093/sleep/zsac105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/15/2022] [Indexed: 11/14/2022] Open
Abstract
Abstract
Study Objectives
Early research suggests that the vestibular system is implicated in lucid dreaming, e.g. frequent lucid dreamers outperform others on static balance tasks. Furthermore, gravity-themed dreams, such as flying dreams, frequently accompany lucid dreaming. Nonetheless, studies are scarce.
Methods
We attempted to: (1) replicate previous findings using more sensitive static balance measures and (2) extend these findings by examining relationships with dreamed gravity imagery more generally. 131 participants (80 F; Mage=24.1 ± 4.1 yrs) estimated lucid dreaming frequency then completed a 5-day home log with ratings for dream lucidity awareness, control, and gravity sensations (flying, falling). They then performed balance tasks on a sensitive force plate, i.e. standing on one or both feet, with eyes open or closed. Center of pressure (CoP) Displacement and CoP Velocity on each trial measured postural stability.
Results
Findings partially support the claim of a vestibular contribution to lucid dreaming. Frequent lucid dreamers displayed better balance (lower CoP Velocity) than did other participants on some trials and lucid dreaming frequency was globally correlated with better balance (lower CoP Velocity). Lower CoP Velocity was related to flying sensations in men’s dreams and with more dream control in women’s dreams. However, body height—possibly due to its relationship to sex—and levels of sleepiness confound some of these effects.
Conclusion
While findings only provide a partial replication of previous work, they nonetheless support an emerging view that the vestibular system underlies basic attributes of bodily self-consciousness, such as feelings of self-agency and self-location, whether such consciousness occurs during wakefulness or dreaming.
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Affiliation(s)
- Claudia Picard-Deland
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM – Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada
- Department of Neuroscience, Université de Montréal, Montréal, Québec, Canada
| | - Max-Antoine Allaire
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM – Hôpital du Sacré-Coeur de Montréal, Montréal, Québec, Canada
- Department of Psychology, Université de Montréal, Montréal, Québec, Canada
| | - Tore Nielsen
- Corresponding author. Tore Nielsen, Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM—Hôpital du Sacré-Cœur de Montréal, 5400 Gouin Blvd West, Montreal, Quebec, Canada H4J 1C5.
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Picard-Deland C, Nielsen T. Targeted memory reactivation has a sleep stage-specific delayed effect on dream content. J Sleep Res 2021; 31:e13391. [PMID: 34018262 DOI: 10.1111/jsr.13391] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/13/2021] [Accepted: 04/29/2021] [Indexed: 12/29/2022]
Abstract
Although new learning is known to reappear in later dream scenarios, the timing of such reappearances remains unclear. Sometimes, references to new learning occur relatively quickly, 1 day post-learning (day-residue effect); at other times there may be a substantive delay, 5-7 days, before such references appear (dream-lag effect). We studied temporal delays in dream reactivation following the learning of a virtual reality (VR) flying task using 10-day home sleep/dream logs, and how these might be influenced by targeted memory reactivation (TMR). Participants were exposed twice to a VR task in the sleep laboratory; once before and once after a 2-hr opportunity to nap (n = 65) or to read (n = 32). Auditory cues associated with the VR task were replayed in either wake, rapid eye movement (REM) sleep, slow-wave sleep (SWS) or were not replayed. Although we previously showed that TMR cueing did not have an immediate effect on dream content, in the present study we extend these results by showing that TMR in sleep has instead a delayed effect on task-dream reactivations: participants dreamed more about the task 1-2 days later when TMR was applied in REM sleep and 5-6 days later when it was applied in SWS sleep, compared to participants with no cueing. Findings may help explain the temporal relationships between dream and memory reactivations and clarify the occurrence of day-residue and dream-lag phenomena.
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Affiliation(s)
- Claudia Picard-Deland
- Dream and Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Montréal, QC, Canada.,Department of Neuroscience, Université de Montréal, Montréal, QC, Canada
| | - Tore Nielsen
- Dream and Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Montréal, QC, Canada.,Department of Psychiatry and Addictology, Université de Montréal, Montréal, QC, Canada
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Picard-Deland C, Aumont T, Samson-Richer A, Paquette T, Nielsen T. Whole-body procedural learning benefits from targeted memory reactivation in REM sleep and task-related dreaming. Neurobiol Learn Mem 2021; 183:107460. [PMID: 34015442 DOI: 10.1016/j.nlm.2021.107460] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/20/2021] [Accepted: 05/12/2021] [Indexed: 10/21/2022]
Abstract
Sleep facilitates memory consolidation through offline reactivations of memory traces. Dreaming may play a role in memory improvement and may reflect these memory reactivations. To experimentally address this question, we used targeted memory reactivation (TMR), i.e., application, during sleep, of a stimulus that was previously associated with learning, to assess whether it influences task-related dream imagery (or task-dream reactivations). Specifically, we asked if TMR or task-dream reactivations in either slow-wave (SWS) or rapid eye movement (REM) sleep benefit whole-body procedural learning. Healthy participants completed a virtual reality (VR) flying task prior to and following a morning nap or rest period during which task-associated tones were readministered in either SWS, REM sleep, wake or not at all. Findings indicate that learning benefits most from TMR when applied in REM sleep compared to a Control-sleep group. REM dreams that reactivated kinesthetic elements of the VR task (e.g., flying, accelerating) were also associated with higher improvement on the task than were dreams that reactivated visual elements (e.g., landscapes) or that had no reactivations. TMR did not itself influence dream content but its effects on performance were greater when coexisting with task-dream reactivations in REM sleep. Findings may help explain the mechanistic relationships between dream and memory reactivations and may contribute to the development of sleep-based methods to optimize complex skill learning.
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Affiliation(s)
- Claudia Picard-Deland
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada; Department of Neuroscience, Université de Montréal, Montréal, Québec, Canada
| | - Tomy Aumont
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada; Department of Biomedical Sciences, Université de Montréal, Montréal, Québec, Canada
| | - Arnaud Samson-Richer
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada
| | - Tyna Paquette
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada
| | - Tore Nielsen
- Dream & Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, CIUSSS-NÎM - Hôpital du Sacré-Coeur de Montréal, Québec, Canada; Department of Psychiatry and Addictology, Université de Montréal, Montréal, Québec, Canada.
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Carr M, Haar Horowitz A, Amores J, Maes P. Towards engineering dreams. Conscious Cogn 2020; 85:103006. [PMID: 32854064 DOI: 10.1016/j.concog.2020.103006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Michelle Carr
- Sleep and Neurophysiology Laboratory, University of Rochester, Rochester, NY, USA.
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