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Kim J, Huang H, Gilbert ET, Arndt KC, English DF, Jia X. T-DOpE probes reveal sensitivity of hippocampal oscillations to cannabinoids in behaving mice. Nat Commun 2024; 15:1686. [PMID: 38402238 PMCID: PMC10894268 DOI: 10.1038/s41467-024-46021-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 02/06/2024] [Indexed: 02/26/2024] Open
Abstract
Understanding the neural basis of behavior requires monitoring and manipulating combinations of physiological elements and their interactions in behaving animals. We developed a thermal tapering process enabling fabrication of low-cost, flexible probes combining ultrafine features: dense electrodes, optical waveguides, and microfluidic channels. Furthermore, we developed a semi-automated backend connection allowing scalable assembly. We demonstrate T-DOpE (Tapered Drug delivery, Optical stimulation, and Electrophysiology) probes achieve in single neuron-scale devices (1) high-fidelity electrophysiological recording (2) focal drug delivery and (3) optical stimulation. The device tip can be miniaturized (as small as 50 µm) to minimize tissue damage while the ~20 times larger backend allows for industrial-scale connectorization. T-DOpE probes implanted in mouse hippocampus revealed canonical neuronal activity at the level of local field potentials (LFP) and neural spiking. Taking advantage of the triple-functionality of these probes, we monitored LFP while manipulating cannabinoid receptors (CB1R; microfluidic agonist delivery) and CA1 neuronal activity (optogenetics). Focal infusion of CB1R agonist downregulated theta and sharp wave-ripple oscillations (SPW-Rs). Furthermore, we found that CB1R activation reduces sharp wave-ripples by impairing the innate SPW-R-generating ability of the CA1 circuit.
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Affiliation(s)
- Jongwoon Kim
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA, USA
| | - Hengji Huang
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA, USA
| | - Earl T Gilbert
- School of Neuroscience, Virginia Tech, Blacksburg, VA, USA
| | - Kaiser C Arndt
- School of Neuroscience, Virginia Tech, Blacksburg, VA, USA
| | | | - Xiaoting Jia
- The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA, USA.
- School of Neuroscience, Virginia Tech, Blacksburg, VA, USA.
- Department of Materials Science and Engineering, Virginia Tech, Blacksburg, VA, USA.
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2
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Brooks-Russell A, Wrobel J, Brown T, Bidwell LC, Wang GS, Steinhart B, Dooley G, Kosnett MJ. Effects of acute cannabis inhalation on reaction time, decision-making, and memory using a tablet-based application. J Cannabis Res 2024; 6:3. [PMID: 38308382 PMCID: PMC10837858 DOI: 10.1186/s42238-024-00215-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 01/13/2024] [Indexed: 02/04/2024] Open
Abstract
BACKGROUND Acute cannabis use has been demonstrated to slow reaction time and affect decision-making and short-term memory. These effects may have utility in identifying impairment associated with recent use. However, these effects have not been widely investigated among individuals with a pattern of daily use, who may have acquired tolerance. The purpose of this study was to examine the impact of tolerance to cannabis on the acute effects as measured by reaction time, decision-making (gap acceptance), and short-term memory. METHODS Participants (ages 25-45) completed a tablet-based (iPad) test battery before and approximately 60 min after smoking cannabis flower. The change in performance from before to after cannabis use was compared across three groups of cannabis users: (1) occasional use (n = 23); (2) daily use (n = 31); or (3) no current use (n = 32). Participants in the occasional and daily use group self-administered ad libitum, by smoking or vaping, self-supplied cannabis flower with a high concentration of total THC (15-30%). RESULTS The occasional use group exhibited decrements in reaction time (slowed) and short-term memory (replicated fewer shapes) from before to after cannabis use, as compared to the no-use group. In the gap acceptance task, daily use participants took more time to complete the task post-smoking cannabis as compared to those with no use or occasional use; however, the level of accuracy did not significantly change. CONCLUSIONS The findings are consistent with acquired tolerance to certain acute psychomotor effects with daily cannabis use. The finding from the gap acceptance task which showed a decline in speed but not accuracy may indicate a prioritization of accuracy over response time. Cognitive and psychomotor assessments may have utility for identifying impairment associated with recent cannabis use.
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Affiliation(s)
- Ashley Brooks-Russell
- Injury and Violence Prevention Center, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, 13001 E. 17Th Place, Aurora, CO, 80045, USA.
| | - Julia Wrobel
- Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Tim Brown
- Driving Safety Research Institute, University of Iowa, Iowa City, IA, USA
| | - L Cinnamon Bidwell
- Institute of Cognitive Science, University of Colorado, Boulder, CO, USA
| | - George Sam Wang
- Department of Pediatrics, CU School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Benjamin Steinhart
- Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Gregory Dooley
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA
| | - Michael J Kosnett
- Department of Medicine, CU School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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3
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Kassim FM, Tod S, Rodger J, Hood SD, Lee JWY, Albrecht MA, Martin-Iverson MT. Nabilone Impairs Spatial and Verbal Working Memory in Healthy Volunteers. Cannabis Cannabinoid Res 2024; 9:199-211. [PMID: 36201240 DOI: 10.1089/can.2022.0099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: Memory impairments and psychosis-like experiences can be adverse effects of cannabis use. However, reports on the cognitive impact of cannabis use are not consistent. There are also limited studies on the psychotomimetic effects of cannabinoid compounds to reveal the association between cannabis and psychosis. Therefore, we investigated the effect of acute cannabinoid intoxication on verbal working memory (VWM) and spatial working memory (SWM) following oral doses of the synthetic cannabinoid agonist, nabilone (1-2 mg, oral). We further investigated the effect of nabilone on psychosis-like experiences (schizotypy scores) and associations of schizotypy with VWM and SWM. Methods: Healthy participants (n=28) completed spatial and digit span tasks across different delay conditions (0, 6, 12, and 18 sec) after receiving nabilone (1-2 mg, PO) or placebo in a randomized, double-blind, counterbalanced, crossover manner. A subset of participants completed a short battery of schizotypy measures (n=25). Results: Nabilone impaired VWM (p=0.03, weak effect size η2=0.02) and SWM (p=0.00016, η2=0.08). Nabilone did not significantly change overall schizotypy scores. Schizotypy scores were negatively correlated with working memory (WM) averaged across all delays and both modalities, under placebo (ρ=-0.41, p=0.04). In addition, there were significant negative correlations between occasions of cannabis use and overall WM averaged scores across drug treatments (ρ=-0.49, p=0.007) and under placebo (ρ=-0.45, p=0.004). The results showed that the drug effect in the less frequent cannabis users was more pronounced on the SWM (p<0.01) and VWM (p<0.01), whereas there appeared to be little drug effect in the frequent cannabis users. Conclusion: Low doses of synthetic cannabinoid impaired SWM and VWM, indicating that exogenous activation of the cannabinoid system influences cognitive performance. Further, the results replicated previous findings that schizotypy is correlated with deficits in WM. Clinical Trial Registry Name: Nabilone and caffeine effects on the perceptions of visually, auditory, tactile and multimodal illusions in healthy volunteers. Clinical Trial Registration Number: CT-2018-CTN-02561 (Therapeutic Goods Administration Clinical Trial Registry) and ACTRN12618001292268 (The Australian New Zealand Clinical Trials Registry).
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Affiliation(s)
- Faiz M Kassim
- Psychopharmacology Research Unit, Discipline of Pharmacology, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Sophie Tod
- Psychopharmacology Research Unit, Discipline of Pharmacology, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Jennifer Rodger
- Experimental and Regenerative Neurosciences, School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Brain Plasticity Group, Perron Institute for Neurological and Translational Science, Nedlands, Western Australia, Australia
| | - Sean D Hood
- Division of Psychiatry, Medical School, University of Western Australia, Perth, Western Australia, Australia
| | - Joseph W Y Lee
- Division of Psychiatry, Medical School, University of Western Australia, Perth, Western Australia, Australia
| | - Matthew A Albrecht
- Western Australian Centre for Road Safety Research, School of Psychological Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Mathew T Martin-Iverson
- Psychopharmacology Research Unit, Discipline of Pharmacology, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia
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Barnard IL, Onofrychuk TJ, Toderash AD, Patel VN, Glass AE, Adrian JC, Laprairie RB, Howland JG. High-THC Cannabis Smoke Impairs Incidental Memory Capacity in Spontaneous Tests of Novelty Preference for Objects and Odors in Male Rats. eNeuro 2023; 10:ENEURO.0115-23.2023. [PMID: 37973381 PMCID: PMC10714893 DOI: 10.1523/eneuro.0115-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 09/19/2023] [Accepted: 10/16/2023] [Indexed: 11/19/2023] Open
Abstract
Working memory is an executive function that orchestrates the use of limited amounts of information, referred to as working memory capacity, in cognitive functions. Cannabis exposure impairs working memory in humans; however, it is unclear whether Cannabis facilitates or impairs rodent working memory and working memory capacity. The conflicting literature in rodent models may be at least partly because of the use of drug exposure paradigms that do not closely mirror patterns of human Cannabis use. Here, we used an incidental memory capacity paradigm where a novelty preference is assessed after a short delay in spontaneous recognition-based tests. Either object or odor-based stimuli were used in test variations with sets of identical [identical stimuli test (IST)] and different [different stimuli test (DST)] stimuli (three or six) for low-memory and high-memory loads, respectively. Additionally, we developed a human-machine hybrid behavioral quantification approach which supplements stopwatch-based scoring with supervised machine learning-based classification. After validating the spontaneous IST and DST in male rats, 6-item test versions with the hybrid quantification method were used to evaluate the impact of acute exposure to high-Δ9-tetrahydrocannabinol (THC) or high-CBD Cannabis smoke on novelty preference. Under control conditions, male rats showed novelty preference in all test variations. We found that high-THC, but not high-CBD, Cannabis smoke exposure impaired novelty preference for objects under a high-memory load. Odor-based recognition deficits were seen under both low-memory and high-memory loads only following high-THC smoke exposure. Ultimately, these data show that Cannabis smoke exposure impacts incidental memory capacity of male rats in a memory load-dependent, and stimuli-specific manner.
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Affiliation(s)
- Ilne L Barnard
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5E5, Canada
| | - Timothy J Onofrychuk
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5E5, Canada
| | - Aaron D Toderash
- Department of Computer Science, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5C9, Canada
| | - Vyom N Patel
- Department of Computer Science, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5C9, Canada
| | - Aiden E Glass
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5E5, Canada
| | - Jesse C Adrian
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5E5, Canada
| | - Robert B Laprairie
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5E5, Canada
- Department of Pharmacology, College of Medicine, Dalhousie University, Halifax, Nova Scotia, B3H 4R2, Canada
| | - John G Howland
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, S7N5E5, Canada
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Wesley MJ, Lile JA. Combining noninvasive brain stimulation with behavioral pharmacology methods to study mechanisms of substance use disorder. Front Neurosci 2023; 17:1150109. [PMID: 37554294 PMCID: PMC10405288 DOI: 10.3389/fnins.2023.1150109] [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: 01/23/2023] [Accepted: 07/06/2023] [Indexed: 08/10/2023] Open
Abstract
Psychotropic drugs and transcranial magnetic stimulation (TMS) are effective for treating certain psychiatric conditions. Drugs and TMS have also been used as tools to explore the relationship between brain function and behavior in humans. Combining centrally acting drugs and TMS has proven useful for characterizing the neural basis of movement. This combined intervention approach also holds promise for improving our understanding of the mechanisms underlying disordered behavior associated with psychiatric conditions, including addiction, though challenges exist. For example, altered neocortical function has been implicated in substance use disorder, but the relationship between acute neuromodulation of neocortex with TMS and direct effects on addiction-related behaviors is not well established. We propose that the combination of human behavioral pharmacology methods with TMS can be leveraged to help establish these links. This perspective article describes an ongoing study that combines the administration of delta-9-tetrahydrocannabinol (THC), the main psychoactive compound in cannabis, with neuroimaging-guided TMS in individuals with problematic cannabis use. The study examines the impact of the left dorsolateral prefrontal cortex (DLPFC) stimulation on cognitive outcomes impacted by THC intoxication, including the subjective response to THC and the impairing effects of THC on behavioral performance. A framework for integrating TMS with human behavioral pharmacology methods, along with key details of the study design, are presented. We also discuss challenges, alternatives, and future directions.
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Affiliation(s)
- Michael J. Wesley
- Department of Behavioral Science, College of Medicine, University of Kentucky, Lexington, KY, United States
- Department of Psychiatry, College of Medicine, University of Kentucky, Lexington, KY, United States
- Department of Psychology, College of Arts and Sciences, University of Kentucky, Lexington, KY, United States
| | - Joshua A. Lile
- Department of Behavioral Science, College of Medicine, University of Kentucky, Lexington, KY, United States
- Department of Psychiatry, College of Medicine, University of Kentucky, Lexington, KY, United States
- Department of Psychology, College of Arts and Sciences, University of Kentucky, Lexington, KY, United States
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6
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Kim J, Huang H, Gilbert E, Arndt K, English DF, Jia X. Tapered Drug delivery, Optical stimulation, and Electrophysiology (T-DOpE) probes reveal the importance of cannabinoid signaling in hippocampal CA1 oscillations in behaving mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.08.544251. [PMID: 37333172 PMCID: PMC10274863 DOI: 10.1101/2023.06.08.544251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Understanding the neural basis of behavior requires monitoring and manipulating combinations of physiological elements and their interactions in behaving animals. Here we developed a thermal tapering process (TTP) which enables the fabrication of novel, low-cost, flexible probes that combine ultrafine features of dense electrodes, optical waveguides, and microfluidic channels. Furthermore, we developed a semi-automated backend connection allowing scalable assembly of the probes. We demonstrate that our T-DOpE ( T apered D rug delivery, Op tical stimulation, and E lectrophysiology) probe achieves in a single neuron-scale device (1) high-fidelity electrophysiological recording (2) focal drug delivery and (3) optical stimulation. With a tapered geometry, the device tip can be minimized (as small as 50 μm) to ensure minimal tissue damage while the backend is ~20 times larger allowing for direct integration with industrial-scale connectorization. Acute and chronic implantation of the probes in mouse hippocampus CA1 revealed canonical neuronal activity at the level of local field potentials and spiking. Taking advantage of the triple-functionality of the T-DOpE probe, we monitored local field potentials with simultaneous manipulation of endogenous type 1 cannabinoid receptors (CB1R; via microfluidic agonist delivery) and CA1 pyramidal cell membrane potential (optogenetic activation). Electro-pharmacological experiments revealed that focal infusion of CB1R agonist CP-55,940 in dorsal CA1 downregulated theta and sharp wave-ripple oscillations. Furthermore, using the full electro-pharmacological-optical feature set of the T-DOpE probe we found that CB1R activation reduces sharp wave-ripples (SPW-Rs) by impairing the innate SPW-R-generating ability of the CA1 circuit.
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7
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Cuttler C, Petrucci AS, LaFrance EM. Cognitive test performance in chronic cannabis flower users, concentrate users, and non-users. Sci Rep 2023; 13:8068. [PMID: 37202444 DOI: 10.1038/s41598-023-35217-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 05/15/2023] [Indexed: 05/20/2023] Open
Abstract
Extremely high-potency cannabis concentrates are becoming increasingly available and popular among consumers. While prior research indicates these products are perceived to have greater detrimental effects relative to cannabis flower, few studies have examined their relative objective effects, and no existing studies have compared the cognitive test performance of sober flower users, concentrate users, and non-users. A total of 198 healthy adults (98 non-users, 46 exclusive flower users, and 54 concentrate users) were administered a battery of tests of memory, psychomotor speed, attention, and executive functioning under sober laboratory-controlled conditions. Significant group differences were detected on tests of verbal free recall and episodic prospective memory, with both the flower users and concentrate users demonstrating significantly worse performance than non-users. Concentrate (but not flower) users performed worse than non-users on a measure of source memory, but contrary to our hypothesis, there were no significant differences between flower and concentrate users on any of the cognitive tests. Results indicate that, under sober conditions, individuals who regularly use concentrates are no more cognitively impacted than those who exclusively use flower. These null findings may reflect the tendency for concentrate users to self-titrate and use significantly lower quantities of concentrates than flower.
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Affiliation(s)
- Carrie Cuttler
- Department of Psychology, Washington State University, PO Box 644820, Pullman, WA, 99164-4820, USA.
| | - Aria S Petrucci
- Department of Psychology, Washington State University, PO Box 644820, Pullman, WA, 99164-4820, USA
| | - Emily M LaFrance
- Department of Psychology, Washington State University, PO Box 644820, Pullman, WA, 99164-4820, USA
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Springer SD, Spooner RK, Schantell M, Arif Y, Frenzel MR, Eastman JA, Wilson TW. Regular recreational Cannabis users exhibit altered neural oscillatory dynamics during attention reorientation. Psychol Med 2023; 53:1205-1214. [PMID: 34889178 PMCID: PMC9250753 DOI: 10.1017/s0033291721002671] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Cannabis is the most widely used illicit drug in the United States and is often associated with changes in attention function, which may ultimately impact numerous other cognitive faculties (e.g. memory, executive function). Importantly, despite the increasing rates of cannabis use and widespread legalization in the United States, the neural mechanisms underlying attentional dysfunction in chronic users are poorly understood. METHODS We used magnetoencephalography (MEG) and a modified Posner cueing task in 21 regular cannabis users and 32 demographically matched non-user controls. MEG data were imaged in the time-frequency domain using a beamformer and peak voxel time series were extracted to quantify the oscillatory dynamics underlying use-related aberrations in attentional reorienting, as well as the impact on spontaneous neural activity immediately preceding stimulus onset. RESULTS Behavioral performance on the task (e.g. reaction time) was similar between regular cannabis users and non-user controls. However, the neural data indicated robust theta-band synchronizations across a distributed network during attentional reorienting, with activity in the bilateral inferior frontal gyri being markedly stronger in users relative to controls (p's < 0.036). Additionally, we observed significantly reduced spontaneous theta activity across this distributed network during the pre-stimulus baseline in cannabis users relative to controls (p's < 0.020). CONCLUSIONS Despite similar performance on the task, we observed specific alterations in the neural dynamics serving attentional reorienting in regular cannabis users compared to controls. These data suggest that regular cannabis users may employ compensatory processing in the prefrontal cortices to efficiently reorient their attention relative to non-user controls.
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Affiliation(s)
- Seth D. Springer
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
- College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Rachel K. Spooner
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
- College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Mikki Schantell
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
- College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Yasra Arif
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
- College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Michaela R. Frenzel
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
- College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Jacob A. Eastman
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
- College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Tony W. Wilson
- Institute for Human Neuroscience, Boys Town National Research Hospital, Boys Town, NE, USA
- College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
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Scheyer A, Yasmin F, Naskar S, Patel S. Endocannabinoids at the synapse and beyond: implications for neuropsychiatric disease pathophysiology and treatment. Neuropsychopharmacology 2023; 48:37-53. [PMID: 36100658 PMCID: PMC9700791 DOI: 10.1038/s41386-022-01438-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/10/2022] [Accepted: 08/18/2022] [Indexed: 11/09/2022]
Abstract
Endocannabinoids (eCBs) are lipid neuromodulators that suppress neurotransmitter release, reduce postsynaptic excitability, activate astrocyte signaling, and control cellular respiration. Here, we describe canonical and emerging eCB signaling modes and aim to link adaptations in these signaling systems to pathological states. Adaptations in eCB signaling systems have been identified in a variety of biobehavioral and physiological process relevant to neuropsychiatric disease states including stress-related disorders, epilepsy, developmental disorders, obesity, and substance use disorders. These insights have enhanced our understanding of the pathophysiology of neurological and psychiatric disorders and are contributing to the ongoing development of eCB-targeting therapeutics. We suggest future studies aimed at illuminating how adaptations in canonical as well as emerging cellular and synaptic modes of eCB signaling contribute to disease pathophysiology or resilience could further advance these novel treatment approaches.
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Affiliation(s)
| | - Farhana Yasmin
- Northwestern Center for Psychiatric Neuroscience, Chicago, IL, USA
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Saptarnab Naskar
- Northwestern Center for Psychiatric Neuroscience, Chicago, IL, USA
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Sachin Patel
- Northwestern Center for Psychiatric Neuroscience, Chicago, IL, USA.
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA.
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10
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Syed SA, Schnakenberg Martin AM, Cortes-Briones JA, Skosnik PD. The Relationship Between Cannabinoids and Neural Oscillations: How Cannabis Disrupts Sensation, Perception, and Cognition. Clin EEG Neurosci 2022:15500594221138280. [PMID: 36426543 DOI: 10.1177/15500594221138280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Disruptions in neural oscillations are believed to be one critical mechanism by which cannabinoids, such as delta-9-tetrahyrdrocannabinol (THC; the primary psychoactive constituent of cannabis), perturbs brain function. Here we briefly review the role of synchronized neural activity, particularly in the gamma (30-80 Hz) and theta (4-7 Hz) frequency range, in sensation, perception, and cognition. This is followed by a review of clinical studies utilizing electroencephalography (EEG) which have demonstrated that both chronic and acute cannabinoid exposure disrupts neural oscillations in humans. We also offer a hypothetical framework through which endocannabinoids modulate neural synchrony at the network level. This also includes speculation on how both chronic and acute cannabinoids disrupt functionally relevant neural oscillations by altering the fine tuning of oscillations and the inhibitory/excitatory balance of neural circuits. Finally, we highlight important clinical implications of such oscillatory disruptions, such as the potential relationship between cannabis use, altered neural synchrony, and disruptions in sensation, perception, and cognition, which are perturbed in disorders such as schizophrenia.
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Affiliation(s)
- Shariful A Syed
- Department of Psychiatry, 12228Yale University School of Medicine, New Haven, CT, USA.,VA Connecticut Healthcare System, West Haven, CT, USA
| | - Ashley M Schnakenberg Martin
- Department of Psychiatry, 12228Yale University School of Medicine, New Haven, CT, USA.,VA Connecticut Healthcare System, West Haven, CT, USA
| | - Jose A Cortes-Briones
- Department of Psychiatry, 12228Yale University School of Medicine, New Haven, CT, USA.,VA Connecticut Healthcare System, West Haven, CT, USA
| | - Patrick D Skosnik
- Department of Psychiatry, 12228Yale University School of Medicine, New Haven, CT, USA.,VA Connecticut Healthcare System, West Haven, CT, USA
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11
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Murray CH, Huang Z, Lee R, de Wit H. Adolescents are more sensitive than adults to acute behavioral and cognitive effects of THC. Neuropsychopharmacology 2022; 47:1331-1338. [PMID: 35110688 PMCID: PMC9117219 DOI: 10.1038/s41386-022-01281-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/16/2022] [Accepted: 01/19/2022] [Indexed: 11/09/2022]
Abstract
Increased cannabis availability has contributed to increased use with concomitant incidence of adverse effects. One risk factor for adverse drug reactions may be age. There is preclinical evidence that acute effects of delta-9-tetrahydrocannabinol (THC), the primary active constituent of cannabis, are greater during adolescence, but this has not been fully studied in humans. The present study sought to determine whether adolescent men and women are more sensitive than adults to acute THC. Adolescents aged 18-20 (N = 12) and adults aged 30-40 (N = 12), with less than 20 total lifetime uses of THC-containing products, received capsules of THC (7.5, 15 mg) and placebo across three study sessions in randomized order under double blind conditions. During each session, subjective, cardiovascular, behavioral, and EEG measures were obtained. Behavioral measures included Simple Reaction Time, Stop Task, Time Production and N-back and EEG measures included P300 amplitudes during an auditory oddball task and eyes-closed resting state. THC affected subjective state and heart rate similarly in both age groups. However, adolescents were more sensitive to performance impairing effects, exhibiting dose-dependent impairments on reaction time, response accuracy, and time perception. On EEG measures, THC dose-dependently decreased P300 amplitude in adolescents but not adults. Adolescents were more sensitive to behavioral and cognitive effects of THC, but not to cardiovascular effects or subjective measures. Thus, at doses that produce comparable ratings of intoxication, adolescents may exhibit greater cognitive impairment and alterations in brain function.
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Affiliation(s)
- Conor H. Murray
- grid.170205.10000 0004 1936 7822Department of Psychiatry and Behavioral Neuroscience, University of Chicago, 5841 S Maryland Ave, Chicago, IL 60637 USA
| | - Zhengyi Huang
- grid.170205.10000 0004 1936 7822Department of Psychiatry and Behavioral Neuroscience, University of Chicago, 5841 S Maryland Ave, Chicago, IL 60637 USA
| | - Royce Lee
- grid.170205.10000 0004 1936 7822Department of Psychiatry and Behavioral Neuroscience, University of Chicago, 5841 S Maryland Ave, Chicago, IL 60637 USA
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, 5841 S Maryland Ave, Chicago, IL, 60637, USA.
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The effects of acute Cannabis smoke or Δ9-THC injections on the trial-unique, nonmatching-to- location and five-choice serial reaction time tasks in male Long-Evans rats. Neurobiol Learn Mem 2022; 192:107624. [DOI: 10.1016/j.nlm.2022.107624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 04/08/2022] [Accepted: 04/24/2022] [Indexed: 11/18/2022]
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13
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Binkowska AA, Jakubowska N, Krystecka K, Galant N, Piotrowska-Cyplik A, Brzezicka A. Theta and Alpha Oscillatory Activity During Working Memory Maintenance in Long-Term Cannabis Users: The Importance of the Polydrug Use Context. Front Hum Neurosci 2021; 15:740277. [PMID: 34733146 PMCID: PMC8558244 DOI: 10.3389/fnhum.2021.740277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 09/23/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Impairments in various subdomains of memory have been associated with chronic cannabis use, but less is known about their neural underpinnings, especially in the domain of the brain's oscillatory activity. Aims: To investigate neural oscillatory activity supporting working memory (WM) in regular cannabis users and non-using controls. We focused our analyses on frontal midline theta and posterior alpha asymmetry as oscillatory fingerprints for the WM's maintenance process. Methods: 30 non-using controls (CG) and 57 regular cannabis users-27 exclusive cannabis users (CU) and 30 polydrug cannabis users (PU) completed a Sternberg modified WM task with a concurrent electroencephalography recording. Theta, alpha and beta frequency bands were examined during WM maintenance. Results: When compared to non-using controls, the PU group displayed increased frontal midline theta (FMT) power during WM maintenance, which was positively correlated with RT. The posterior alpha asymmetry during the maintenance phase, on the other hand, was negatively correlated with RT in the CU group. WM performance did not differ between groups. Conclusions: Both groups of cannabis users (CU and PU), when compared to the control group, displayed differences in oscillatory activity during WM maintenance, unique for each group (in CU posterior alpha and in PU FMT correlated with performance). We interpret those differences as a reflection of compensatory strategies, as there were no differences between groups in task performance. Understanding the psychophysiological processes in regular cannabis users may provide insight on how chronic use may affect neural networks underlying cognitive processes, however, a polydrug use context (i.e., combining cannabis with other illegal substances) seems to be an important factor.
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Affiliation(s)
| | - Natalia Jakubowska
- SWPS University of Social Sciences and Humanities, Warsaw, Poland.,Polish-Japanese Academy of Information Technology, Warsaw, Poland
| | | | | | | | - Aneta Brzezicka
- SWPS University of Social Sciences and Humanities, Warsaw, Poland
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14
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Richard CD, Poole JR, McConnell M, Meghdadi AH, Stevanovic-Karic M, Rupp G, Fink A, Schmitt R, Brown TL, Berka C. Alterations in Electroencephalography Theta as Candidate Biomarkers of Acute Cannabis Intoxication. Front Neurosci 2021; 15:744762. [PMID: 34671242 PMCID: PMC8520987 DOI: 10.3389/fnins.2021.744762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 09/15/2021] [Indexed: 01/25/2023] Open
Abstract
The trend toward cannabis legalization in the United States over the past two decades has unsurprisingly been accompanied by an increase in the number of cannabis users and use patterns that potentially pose wider risks to the public like driving under the influence. As such, it is becoming increasingly important to develop methods to accurately quantify cannabis intoxication and its associated impairments on cognitive and motor function. Electroencephalography (EEG) offers a non-invasive method for quantitatively assessing neurophysiological biomarkers of intoxication and impairment with a high degree of temporal resolution. Twelve healthy, young recreational cannabis users completed a series of neurocognitive tasks with concurrent EEG acquisition using the ABM STAT X24 EEG headset in a within-subject counterbalanced design. The 1-h testbed consisted of resting state tasks and tests of attention and memory. Spectral densities were computed for resting state tasks, and event-related potentials (ERPs) were obtained for the attention and memory tasks. Theta band power (3–5 Hz) was decreased during cannabis intoxication compared to placebo during resting state tasks, as were average P400 and late positive potential (LPP) amplitudes during attention and memory tasks. Cannabis intoxication was also associated with elevated frontal coherence and diminished anterior–posterior coherence in the Theta frequency band. This work highlights the utility of EEG to identify and quantify neurophysiological biomarkers from recordings obtained during a short neurocognitive testbed as a method for profiling cannabis intoxication. These biomarkers may prove efficacious in distinguishing intoxicated from non-intoxicated individuals in lab and real-world settings.
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Affiliation(s)
| | - Jared R Poole
- Advanced Brain Monitoring, Carlsbad, CA, United States
| | | | | | | | - Greg Rupp
- Advanced Brain Monitoring, Carlsbad, CA, United States
| | - Abigail Fink
- Advanced Brain Monitoring, Carlsbad, CA, United States
| | - Rose Schmitt
- National Advanced Driving Simulator, The University of Iowa, Iowa City, IA, United States
| | - Timothy L Brown
- National Advanced Driving Simulator, The University of Iowa, Iowa City, IA, United States
| | - Chris Berka
- Advanced Brain Monitoring, Carlsbad, CA, United States
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15
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Acute effects of high-potency cannabis flower and cannabis concentrates on everyday life memory and decision making. Sci Rep 2021; 11:13784. [PMID: 34215784 PMCID: PMC8253757 DOI: 10.1038/s41598-021-93198-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 06/22/2021] [Indexed: 11/15/2022] Open
Abstract
Statewide legislation has increased public access to high-potency cannabis flower and concentrates, yet federal restrictions limit researchers’ access to relatively low-potency whole-plant cannabis. The goal of this study was to examine the acute effects of high-potency cannabis on cognition using a novel methodology. We further sought to compare cognitive effects of high-potency cannabis flower with and without cannabidiol (CBD), as well as cannabis concentrates to cannabis flower. 80 cannabis users were randomly assigned to stay sober or use their funds to purchase one of three high-potency cannabis products: (1) high-potency flower (≥ 20% THC) without CBD, (2) high-potency flower with CBD, (3) high-potency concentrates (≥ 60% THC) with CBD. Participants were observed over Zoom videoconferencing while inhaling their product or remaining sober and then were administered tests of everyday life memory (prospective, source, temporal order, and false memory) and decision making (risky choice framing, consistency in risk perception, resistance to sunk cost, and over/under confidence) over Zoom. High-potency cannabis flower with CBD impaired free recall, high-potency flower without CBD and concentrates had detrimental effects on source memory, and all three products increased susceptibility to false memories. CBD did not offset impairments and concentrates were self-titrated producing comparable intoxication and impairment as flower.
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16
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Kloft L, Monds LA, Blokland A, Ramaekers JG, Otgaar H. Hazy memories in the courtroom: A review of alcohol and other drug effects on false memory and suggestibility. Neurosci Biobehav Rev 2021; 124:291-307. [PMID: 33587958 DOI: 10.1016/j.neubiorev.2021.02.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 01/26/2021] [Accepted: 02/04/2021] [Indexed: 12/25/2022]
Abstract
Alcohol and other psychoactive drugs are oftentimes implicated in legal cases. A pertinent question herein is whether such substances might adversely affect testimonies of victims, eyewitnesses, or suspects by propelling the formation of false memory and increasing susceptibility to suggestion. In the current review, we amassed all available evidence on the effects of intoxication on false memory formation and suggestibility, including the substances alcohol, benzodiazepines, cannabis, stimulants, hallucinogens, and antipsychotics. Our review indicated that alcohol and cannabis under certain conditions increased the susceptibility to false memories and/or suggestion with effect sizes ranging from medium to large. When intoxicated during an event, alcohol is most likely to increase this susceptibility at high intoxication levels or after a delay, whereas cannabis exerts detrimental effects during acute intoxication but not necessarily once sober. For other substances, ecologically valid research separating different memory phases is needed. Overall, differences between substances regarding false memory effects exist, suggesting that a nuanced approach is needed when dealing with intoxicated individuals in a legal context.
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Affiliation(s)
- Lilian Kloft
- Faculty of Psychology and Neuroscience, Maastricht University, the Netherlands.
| | - Lauren A Monds
- Faculty of Medicine and Health, The University of Sydney, Australia
| | - Arjan Blokland
- Faculty of Psychology and Neuroscience, Maastricht University, the Netherlands
| | | | - Henry Otgaar
- Faculty of Psychology and Neuroscience, Maastricht University, the Netherlands; Faculty of Law, Catholic University of Leuven, Belgium
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17
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Zhornitsky S, Pelletier J, Assaf R, Giroux S, Li CSR, Potvin S. Acute effects of partial CB 1 receptor agonists on cognition - A meta-analysis of human studies. Prog Neuropsychopharmacol Biol Psychiatry 2021; 104:110063. [PMID: 32791166 DOI: 10.1016/j.pnpbp.2020.110063] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/05/2020] [Accepted: 08/05/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND Impairment in cognition is frequently associated with acute cannabis consumption. However, some questions remain unanswered as to which deficits are most prominent and which demographic groups are most vulnerable. METHODS A literature search yielded 52 experimental studies of acute administration of partial CB1 receptor agonists (i.e. cannabis, THC, and nabilone) that assessed cognitive dysfunction in 1580 healthy volunteers. Effect size estimates were calculated using the Comprehensive Meta-Analysis for the following six cognitive domains: attention, executive functions, impulsivity, speed of processing, verbal learning/memory, and working memory. RESULTS There were small-to-moderate impairments across all cognitive domains. Deficits in verbal learning/memory and working memory were more prominent, whereas attention and impulsivity were the least affected. Meta-regression analysis revealed that the greater the male ratio is in a sample, the greater the negative effect of cannabinoids on speed of processing and impulsivity. Analysis of route of administration showed that the deficits in speed of processing were smaller in the oral, relative to smoking, vaping, and intravenous administration studies. A publication bias was observed. DISCUSSION Verbal learning/memory and working memory are most prominently affected by acute administration of partial CB1 receptor agonists. The results are consistent with the residual cognitive effects that have been documented among chronic cannabis users.
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Affiliation(s)
- Simon Zhornitsky
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, United States of America
| | - Julie Pelletier
- Department of Psychiatry, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Roxane Assaf
- Department of Psychiatry, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada; Centre de recherche de l'Institut Universitaire en Santé Mentale de Montréal, Montreal, QC, Canada
| | - Sarah Giroux
- Department of Psychology, Université de Montréal, Montréal, QC, Canada
| | - Chiang-Shan R Li
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, United States of America; Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06520, United States of America; Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06520, United States of America
| | - Stephane Potvin
- Department of Psychiatry, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada; Centre de recherche de l'Institut Universitaire en Santé Mentale de Montréal, Montreal, QC, Canada.
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18
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Muzaffar A, Ullah S, Subhan F, Nazar Z, Hussain SM, Khuda F, Khan A, Khusro A, Sahibzada MUK, Albogami S, El-Shehawi AM, Emran TB, Javed B, Ali J. Clinical Investigation on the Impact of Cannabis Abuse on Thyroid Hormones and Associated Psychiatric Manifestations in the Male Population. Front Psychiatry 2021; 12:730388. [PMID: 34925083 PMCID: PMC8678041 DOI: 10.3389/fpsyt.2021.730388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 11/01/2021] [Indexed: 12/03/2022] Open
Abstract
Cannabis abuse is a common public health issue and may lead to considerable adverse effects. Along with other effects, the dependence on cannabis consumption is a serious problem which has significant consequences on biochemical and clinical symptoms. This study intends to evaluate the harmful effects of the use of cannabis on thyroid hormonal levels, cardiovascular indicators, and psychotic symptoms in the included patients. This prospective multicenter study was conducted on cannabis-dependent patients with psychotic symptoms (n = 40) vs. healthy control subjects (n = 40). All participants were evaluated for psychiatric, biochemical, and cardiovascular physiological effects. Patients were selected through Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV criteria and urine samples, exclusively for the evaluation of cannabis presence. Serum thyroid stimulating hormone (TSH), T3, and T4 levels were measured using the immunoassay technique. Patients were assessed for severity of depressive, schizophrenic, and manic symptoms using international ranking scales. Various quantifiable factors were also measured for the development of tolerance by cannabis. Among the patients of cannabis abuse, 47.5% were found with schizophrenia, 20% with schizoaffective symptoms, 10% with manic symptoms, and 22.5% with both manic and psychotic symptoms. In the group-group and within-group statistical analysis, the results of thyroid hormones and cardiovascular parameters were non-significant. The psychiatric assessment has shown highly significant (p < 0.001) difference of positive, negative, general psychopathology, and total scores [through Positive and Negative Syndrome Scale (PANSS) rating scales] in patients vs. the healthy control subjects. The study revealed that cannabis abuse did not significantly alter thyroid hormones and cardiovascular parameters due to the development of tolerance. However, the cannabis abuse might have a significant contributing role in the positive, negative, and manic symptoms in different psychiatric disorders.
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Affiliation(s)
- Anum Muzaffar
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Sami Ullah
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Fazal Subhan
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Zahid Nazar
- Department of Psychiatry, Lady Reading Hospital MTI Peshawar, Peshawar, Pakistan
| | | | - Fazli Khuda
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Abuzar Khan
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Ameer Khusro
- Research Department of Plant Biology and Biotechnology, Loyola College, Chennai, India
| | | | - Sarah Albogami
- Department of Biotechnology, College of Science, Taif University, Taif, Saudi Arabia
| | - Ahmed M El-Shehawi
- Department of Biotechnology, College of Science, Taif University, Taif, Saudi Arabia
| | - Talha Bin Emran
- Department of Pharmacy, BGC Trust University Bangladesh, Chittagong, Bangladesh
| | - Binish Javed
- Atal Bihari Vajpayee Institute of Medical Sciences, Dr. Ram Manohar Lohia Hospital, New Delhi, India
| | - Javed Ali
- Department of Pharmaceutics, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India
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19
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Curran T, Devillez H, YorkWilliams SL, Bidwell LC. Acute effects of naturalistic THC vs. CBD use on recognition memory: a preliminary study. J Cannabis Res 2020; 2:28. [PMID: 33526107 PMCID: PMC7819319 DOI: 10.1186/s42238-020-00034-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 08/20/2020] [Indexed: 11/10/2022] Open
Abstract
The ratio of ∆9-tetrahydrocannabinol (THC) to cannabidiol (CBD) varies widely across cannabis strains. CBD has opposite effects to THC on a variety of cognitive functions, including acute THC-induced memory impairments. However, additional data are needed, especially under naturalistic conditions with higher potency forms of cannabis, commonly available in legal markets. The goal of this study was to collect preliminary data on the acute effects of different THC:CBD ratios on memory testing in a brief verbal recognition task under naturalistic conditions, using legal-market Colorado dispensary products. Thirty-two regular cannabis users consumed cannabis of differing THC and CBD levels purchased from a dispensary and were assessed via blood draw and a verbal recognition memory test both before (pretest) and after (posttest) ad libitum home administration in a mobile laboratory. Memory accuracy decreased as post-use THC blood levels increased (n = 29), whereas performance showed no relationship to CBD blood levels. When controlling for post-use THC blood levels as a covariate, participants using primarily THC-based strains showed significantly worse memory accuracy post-use, whereas subjects using strains containing both THC and CBD showed no differences between pre- and post-use memory performance. Using a brief and sensitive verbal recognition task, our study demonstrated that naturalistic, acute THC use impairs memory in a dose dependent manner, whereas the combination of CBD and THC was not associated with impairment.
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Affiliation(s)
- Tim Curran
- Department of Psychology and Neuroscience, UCB 345, University of Colorado Boulder, Boulder, CO, 80309-0345, USA.
| | - Hélène Devillez
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO, 80309-0345, USA
| | - Sophie L YorkWilliams
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO, 80309-0345, USA
| | - L Cinnamon Bidwell
- Department of Psychology and Neuroscience, Institute of Cognitive Science, University of Colorado Boulder, Boulder, CO, 80309-0345, USA
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20
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Soriano D, Vacotto M, Brusco A, Caltana L. Neuronal and synaptic morphological alterations in the hippocampus of cannabinoid receptor type 1 knockout mice. J Neurosci Res 2020; 98:2245-2262. [DOI: 10.1002/jnr.24694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 05/28/2020] [Accepted: 06/27/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Delia Soriano
- Universidad de Buenos Aires. Facultad de Medicina. 1° Unidad Académica del Departamento de Histología, Embriología, Biología Celular y Genética. Buenos Aires. Argentina. Buenos Aires Argentina
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis (IBCN) CONICET‐Universidad de Buenos Aires Buenos Aires Argentina
| | - Marina Vacotto
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis (IBCN) CONICET‐Universidad de Buenos Aires Buenos Aires Argentina
| | - Alicia Brusco
- Universidad de Buenos Aires. Facultad de Medicina. 1° Unidad Académica del Departamento de Histología, Embriología, Biología Celular y Genética. Buenos Aires. Argentina. Buenos Aires Argentina
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis (IBCN) CONICET‐Universidad de Buenos Aires Buenos Aires Argentina
| | - Laura Caltana
- Universidad de Buenos Aires. Facultad de Medicina. 1° Unidad Académica del Departamento de Histología, Embriología, Biología Celular y Genética. Buenos Aires. Argentina. Buenos Aires Argentina
- Instituto de Biología Celular y Neurociencia Prof. E. De Robertis (IBCN) CONICET‐Universidad de Buenos Aires Buenos Aires Argentina
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21
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Dunn AL, Michie PT, Hodgson DM, Harms L. Adolescent cannabinoid exposure interacts with other risk factors in schizophrenia: A review of the evidence from animal models. Neurosci Biobehav Rev 2020; 116:202-220. [PMID: 32610181 DOI: 10.1016/j.neubiorev.2020.06.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 06/23/2020] [Accepted: 06/24/2020] [Indexed: 12/18/2022]
Abstract
Many factors and their interaction are linked to the aetiology of schizophrenia, leading to the development of animal models of multiple risk factors and adverse exposures. Differentiating between separate and combined effects for each factor could better elucidate schizophrenia pathology, and drive development of preventative strategies for high-load risk factors. An epidemiologically valid risk factor commonly associated with schizophrenia is adolescent cannabis use. The aim of this review is to evaluate how early-life adversity from various origins, in combination with adolescent cannabinoid exposure interact, and whether these interactions confer main, synergistic or protective effects in animal models of schizophrenia-like behavioural, cognitive and morphological alterations. Patterns emerge regarding which models show consistent synergistic or protective effects, particularly those models incorporating early-life exposure to maternal deprivation and maternal immune activation, and sex-specific effects are observed. It is evident that more research needs to be conducted to better understand the risks and alterations of interacting factors, with particular interest in sex differences, to better understand the translatability of these preclinical models to humans.
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Affiliation(s)
- Ariel L Dunn
- School of Psychology, Faculty of Science, University of Newcastle, Callaghan, NSW 2308, Australia; Priority Centre for Brain and Mental Health Research, University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Patricia T Michie
- School of Psychology, Faculty of Science, University of Newcastle, Callaghan, NSW 2308, Australia; Priority Centre for Brain and Mental Health Research, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia.
| | - Deborah M Hodgson
- School of Psychology, Faculty of Science, University of Newcastle, Callaghan, NSW 2308, Australia; Priority Centre for Brain and Mental Health Research, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia.
| | - Lauren Harms
- Priority Centre for Brain and Mental Health Research, University of Newcastle, Callaghan, NSW 2308, Australia; School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW 2308, Australia; Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia.
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22
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Liao WT, Chang CL, Hsiao YT. Activation of cannabinoid type 1 receptors decreases the synchronization of local field potential oscillations in the hippocampus and entorhinal cortex and prolongs the interresponse time during a differential-reinforcement-of-low-rate task. Eur J Neurosci 2020; 52:4249-4266. [PMID: 32510690 DOI: 10.1111/ejn.14856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 05/01/2020] [Accepted: 05/30/2020] [Indexed: 01/04/2023]
Abstract
Marijuana intoxication impairs neurocognitive functions. Common side effects of consuming cannabis include time distortion and memory loss. However, the underlying neurophysiological mechanisms involved in these effects remain unclear. We hypothesized that communication between the hippocampal CA1 region and medial entorhinal cortex (MEC) is essential for the transmission of temporal-associated information. We used a differential-reinforcement-of-low-rate (DRL) task, which requires subjects to press a lever at an optimal time point, to correlate the distributions of interresponse time (IRT) with local field potentials (LFPs) recorded in the CA1 and MEC under the effects of a cannabinoid type 1 (CB1) receptor agonist. We used a DRL 10-s schedule and trained the rats to withhold for 10 s before pressing a lever. Our data showed that the percentage of 12.4- to 14-s IRT events rose after activation of CB1 receptors in the MEC. In addition, gamma amplitude synchronization and CA1 theta phase-MEC gamma amplitude coupling decreased during the 6- to 14-s IRT events. These results suggest that activation of CB1 receptors in the MEC disrupt the functional connectivity between the CA1 and the MEC. This inefficient communication may result in increased IRT during a DRL schedule. Overall, we postulate that marijuana intoxication impairs the communication between the CA1 and MEC and influences behavioral performances that require precise timing ability.
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Affiliation(s)
- Wan-Ting Liao
- Department of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Chao-Lin Chang
- Department of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Yi-Tse Hsiao
- Department of Veterinary Medicine, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
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23
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Daniju Y, Bossong MG, Brandt K, Allen P. Do the effects of cannabis on the hippocampus and striatum increase risk for psychosis? Neurosci Biobehav Rev 2020; 112:324-335. [PMID: 32057817 DOI: 10.1016/j.neubiorev.2020.02.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 01/17/2020] [Accepted: 02/10/2020] [Indexed: 11/19/2022]
Abstract
Cannabis use is associated with increased risk of psychotic symptoms and in a small number of cases it can lead to psychoses. This review examines the neurobiological mechanisms that mediate the link between cannabis use and psychosis risk. We use an established preclinical model of psychosis, the methylazoxymethanol acetate (MAM) rodent model, as a framework to examine if psychosis risk in some cannabis users is mediated by the effects of cannabis on the hippocampus, and this region's role in the regulation of mesolimbic dopamine. We also examine how cannabis affects excitatory neurotransmission known to regulate hippocampal neural activity and output. Whilst there is clear evidence that cannabis/cannabinoids can affect hippocampal and medial temporal lobe function and structure, the evidence that cannabis/cannabinoids increase striatal dopamine function is less robust. There is limited evidence that cannabis use affects cortical and striatal glutamate levels, but there are currently too few studies to draw firm conclusions. Future work is needed to test the MAM model in relation to cannabis using multimodal neuroimaging approaches.
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Affiliation(s)
- Y Daniju
- Department of Psychology, University of Roehampton, London, UK
| | - M G Bossong
- Department of Psychiatry, UMC Utrecht Brain Center, University Medical Center Utrecht, the Netherlands
| | - K Brandt
- Department of Psychology, University of Roehampton, London, UK
| | - P Allen
- Department of Psychology, University of Roehampton, London, UK; Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK; Icahn School of Medicine at Mount Sinai Hospital, New York, USA.
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24
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Doss MK, Weafer J, Gallo DA, de Wit H. Δ 9-Tetrahydrocannabinol During Encoding Impairs Perceptual Details yet Spares Context Effects on Episodic Memory. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2020; 5:110-118. [PMID: 31668830 PMCID: PMC6954333 DOI: 10.1016/j.bpsc.2019.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/25/2019] [Accepted: 08/20/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND With the growing acceptance of cannabis use, it is crucial to understand the drug's effects on episodic memory accuracy and distortion. We investigated the impact of the administration of Δ9-tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, on a context-based memory illusion. METHODS In a double-blind, placebo-controlled, within-subjects design, healthy infrequent cannabis users (N = 24) memorized object pictures that were superimposed over scenes (e.g., gray cat on beach) after pretreatment with placebo or THC (15 mg oral). Two days later under sober conditions, memory for the object pictures was tested by asking participants to discriminate between previously seen objects or perceptually similar lures (e.g., different gray cat). Context reinstatement was manipulated by presenting objects on their original or different scenes (e.g., beach or forest). RESULTS THC impaired memory for perceptual details of objects compared with placebo, and the context illusion was obtained in each condition: context reinstatement increased high-confidence false recognition along with correct recognition of previously seen objects. Although THC did not interact with these context effects overall, post hoc analyses showed that THC magnified the context illusion when objects were semantically congruent with their encoding contexts but abolished the context illusion when objects were incongruent with their encoding contexts. CONCLUSIONS These results are consistent with the hypothesis that THC impairs the encoding of specific object information more than item-context associations. As a result, THC may spare the distorting effects of context reinstatement on memory. In fact, THC may increase these distorting effects under conditions when objects are semantically congruent with context.
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Affiliation(s)
- Manoj K Doss
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University, Baltimore, Maryland; Department of Psychology, University of Chicago, Chicago, Illinois.
| | - Jessica Weafer
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois; Department of Psychology, University of Kentucky, Lexington, Kentucky
| | - David A Gallo
- Department of Psychology, University of Chicago, Chicago, Illinois
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois
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Chow RM, Marascalchi B, Abrams WB, Peiris NA, Odonkor CA, Cohen SP. Driving Under the Influence of Cannabis: A Framework for Future Policy. Anesth Analg 2019; 128:1300-1308. [PMID: 31094805 DOI: 10.1213/ane.0000000000003575] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Marijuana is the most widely consumed illicit substance in the United States, and an increasing number of states have legalized it for both medicinal and recreational purposes. As it becomes more readily available, there will be a concurrent rise in the number of users and, consequently, the number of motor vehicle operators driving under the influence. This article examines the cognitive and psychomotor effects of cannabis, as well as current policy concerning driving under the influence of drugs. The authors performed a MEDLINE search on the epidemiology of cannabis use, its cognitive and psychomotor effects, and policies regarding driving under the influence of drugs. Twenty-eight epidemiological studies, 16 acute cognitive and psychomotor studies, 8 chronic cognitive and psychomotor studies, and pertinent state and federal laws and policies were reviewed. These search results revealed that marijuana use is associated with significant cognitive and psychomotor effects. In addition, the legalization of marijuana varies from state to state, as do the laws pertaining to driving under the influence of drugs. Marijuana is a commonly found illicit substance in motor vehicle operators driving under the influence of drugs. Current evidence shows that blood levels of tetrahydrocannabinol do not correlate well with the level of impairment. In addition, although acute infrequent use of cannabis typically leads to cognitive and psychomotor impairment, this is not consistently the case for chronic heavy use. To establish the framework for driving under the influence of cannabis policy, we must review the current published evidence and examine existing policy at state and federal levels.
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Affiliation(s)
- Robert M Chow
- From the Department of Anesthesiology, Yale School of Medicine, New Haven, Connecticut
| | | | - Winfred B Abrams
- Physical Medicine & Rehabilitation, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Nathalie A Peiris
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Charles A Odonkor
- Physical Medicine & Rehabilitation, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Steven P Cohen
- Department of Anesthesiology, Neurology and Physical Medicine and Rehabilitation, Johns Hopkins School of Medicine, Baltimore, Maryland
- Department of Anesthesiology and Physical Medicine & Rehabilitation, Walter Reed National Military Medical Center, Uniformed Services University of the Health Sciences, Bethesda, Maryland
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Kloft L, Otgaar H, Blokland A, Garbaciak A, Monds LA, Ramaekers JG. False memory formation in cannabis users: a field study. Psychopharmacology (Berl) 2019; 236:3439-3450. [PMID: 31250074 PMCID: PMC6892757 DOI: 10.1007/s00213-019-05309-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/18/2019] [Indexed: 12/20/2022]
Abstract
RATIONALE Cannabis use is widespread and has previously been associated with memory impairments. However, the role of cannabis in relation to false memory production, i.e., memories of events that were not experienced, is less well-understood. OBJECTIVE The aim of the current field study was to examine the impact of cannabis use on false memory production. METHODS The Deese/Roediger-McDermott (DRM) paradigm was used to induce false memories. In this paradigm, participants study word lists that are associatively related to a non-presented word, termed the critical lure. In a later memory test, true recognition rates and false alarm rates toward critical lures and unrelated items are assessed. Memory performance was compared between three groups: regular cannabis consumers who were acutely intoxicated (n = 53), regular cannabis consumers who were sober (n = 50), and cannabis-naïve controls (n = 53). The participants were approached in Dutch coffee shops (cannabis outlets) and cafes and asked to participate in our study. After collecting general information on their cannabis use, they were subjected to the DRM procedure. RESULTS Although false memory rates for critical lures did not statistically differ between groups, both intoxicated and sober cannabis consumers falsely recognized more unrelated items than control participants. Also, individuals without a history of cannabis use demonstrated higher memory accuracy compared with the intoxicated group. CONCLUSION It is concluded that cannabis intoxication and history of cannabis use induce a liberal response criterion for newly presented words for which the level of association with previously learned words is low and uncertainty is high.
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Affiliation(s)
- Lilian Kloft
- Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands.
| | - Henry Otgaar
- Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands ,Faculty of Law, Catholic University of Leuven, Leuven, Belgium
| | - Arjan Blokland
- Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Alicja Garbaciak
- Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Lauren A. Monds
- Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Johannes G. Ramaekers
- Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
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Enhancing effects of acute exposure to cannabis smoke on working memory performance. Neurobiol Learn Mem 2018; 157:151-162. [PMID: 30521850 DOI: 10.1016/j.nlm.2018.12.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/27/2018] [Accepted: 12/01/2018] [Indexed: 12/29/2022]
Abstract
Numerous preclinical studies show that acute cannabinoid administration impairs cognitive performance. Almost all of this research has employed cannabinoid injections, however, whereas smoking is the preferred route of cannabis administration in humans. The goal of these experiments was to systematically determine how acute exposure to cannabis smoke affects working memory performance in a rat model. Adult male (n = 15) and female (n = 16) Long-Evans rats were trained in a food-motivated delayed response working memory task. Prior to test sessions, rats were exposed to smoke generated by burning different numbers of cannabis or placebo cigarettes, using a within-subjects design. Exposure to cannabis smoke had no effect on male rats' performance, but surprisingly, enhanced working memory accuracy in females, which tended to perform less accurately than males under baseline conditions. In addition, cannabis smoke enhanced working memory accuracy in a subgroup of male rats that performed comparably to the worst-performing females. Exposure to placebo smoke had no effect on performance, suggesting that the cannabinoid content of cannabis smoke was critical for its effects on working memory. Follow-up experiments showed that acute administration of either Δ9-tetrahydrocannabinol (0.0, 0.3, 1.0, 3.0 mg/kg) or the cannabinoid receptor type 1 antagonist rimonabant (0.0, 0.2, 0.6, 2.0 mg/kg) impaired working memory performance. These results indicate that differences in the route, timing, or dose of cannabinoid administration can yield distinct cognitive outcomes, and highlight the need for further investigation of this topic.
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Doss MK, Weafer J, Gallo DA, de Wit H. Δ 9-Tetrahydrocannabinol at Retrieval Drives False Recollection of Neutral and Emotional Memories. Biol Psychiatry 2018; 84:743-750. [PMID: 29884456 DOI: 10.1016/j.biopsych.2018.04.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/05/2018] [Accepted: 04/26/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND It is well established that the main psychoactive constituent of cannabis, Δ9-tetrahydrocannabinol (THC), impairs episodic memory encoding and modulates emotional processing, but little is known about the impact of THC during the retrieval of emotional episodic memories. With the rise of cannabis to treat medical conditions, including those characterized by emotional and episodic memory disturbances, there is an urgent need to determine the effects of THC on memory accuracy and distortion. Here, we report the first study investigating the effects of THC during retrieval of neutral and emotional episodic memories. METHODS Using a double-blind, placebo-controlled, within-subjects design, healthy volunteers (N = 23) viewed negative, neutral, and positive pictures (emotional memory task) and lists of semantically related words (false memory task). Forty-eight hours later, participants ingested a capsule containing either THC (15 mg) or placebo and completed tasks to test their memories for the previously studied pictures and words. RESULTS THC during retrieval did not reduce the number of correct responses to studied items. Instead, it robustly increased false recollection on both the emotional memory and false memory tasks. This effect was found for both neutral and emotional items. CONCLUSIONS These findings show that THC has adverse effects during memory retrieval, distorting both neutral and emotional memories. Coupled with THC's known effects during encoding, these new retrieval findings are important in light of the spreading acceptance of cannabis.
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Affiliation(s)
- Manoj K Doss
- Department of Psychology, the University of Chicago, Chicago, Illinois.
| | - Jessica Weafer
- Department of Psychiatry and Behavioral Neuroscience, the University of Chicago, Chicago, Illinois
| | - David A Gallo
- Department of Psychology, the University of Chicago, Chicago, Illinois
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, the University of Chicago, Chicago, Illinois
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29
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Cannabis users exhibit increased cortical activation during resting state compared to non-users. Neuroimage 2018; 179:176-186. [PMID: 29894828 PMCID: PMC6693493 DOI: 10.1016/j.neuroimage.2018.06.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/18/2018] [Accepted: 06/08/2018] [Indexed: 12/16/2022] Open
Abstract
Studies have shown altered task-based brain functioning as a result of cannabis use. To date, however, whether similar alterations in baseline resting state and functional organization of neural activity are observable in cannabis users remains unknown. We characterized global resting state cortical activations and functional connectivity via electroencephalography (EEG) in cannabis users and related these activations to measures of cannabis use. Resting state EEG in the eyes closed condition was collected from age- and sex-matched cannabis users (N = 17; 6 females; mean age = 30.9 ± 7.4 years) and non-using controls (N = 21; 9 females; mean age = 33.1 ± 11.6 years). Power spectral density and spectral coherence were computed to determine differences in cortical activations and connectivity between the two groups in the delta (1-4Hz), theta (4-7 Hz), alpha (8-12 Hz), beta (13-30 Hz), and gamma (31-50 Hz) frequency bands. Cannabis users exhibited decreased delta and increased theta, beta, and gamma power compared to controls, suggesting increased cortical activation in resting state and a disinhibition of inhibitory functions that may interrupt cognitive processes. Cannabis users also exhibited increased interhemispheric and intrahemispheric coherence relative to controls, reduced mean network degree, and increased clustering coefficient in specific regions and frequencies. This increased cortical activity may indicate a loss of neural refinement and efficiency that may indicate a "noisy" brain. Lastly, measures related to cannabis use were correlated with spectral power and functional connectivity measures, indicating that specific electrophysiological signals are associated with cannabis use. These results suggest that there are differences in cortical activity and connectivity between cannabis users and non-using controls in the resting state that may be related to putative cognitive impairments and can inform effectiveness of intervention programs.
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31
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Mahedy L, Field M, Gage S, Hammerton G, Heron J, Hickman M, Munafò MR. Alcohol Use in Adolescence and Later Working Memory: Findings From a Large Population-Based Birth Cohort. Alcohol Alcohol 2018; 53:251-258. [PMID: 29329371 PMCID: PMC5913665 DOI: 10.1093/alcalc/agx113] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 12/07/2017] [Indexed: 11/14/2022] Open
Abstract
Aims The study aimed to examine the association between adolescent alcohol use and working memory (WM) using a large population sample. Methods Data from the Avon Longitudinal Study of Parents and Children were used to investigate the association between alcohol use at age 15 years and WM 3 years later, assessed using the N-back task (N ~ 3300). A three-category ordinal variable captured mutually exclusive alcohol groupings ranging in order of severity (i.e. low alcohol users, frequent drinkers and frequent/binge drinkers). Differential dropout was accounted for using multiple imputation and inverse probability weighting. Adjustment was made for potential confounders. Results There was evidence of an association between frequent/binge drinking (compared to the low alcohol group) and poorer performance on the 3-back task after adjusting for sociodemographic confounding variables, WM at age 11 years, and experience of a head injury/unconsciousness before age 11 years (β = −0.23, 95% CI = −0.37 to −0.09, P = 0.001). However, this association was attenuated (β = −0.12, 95% CI = −0.27 to 0.03, P = 0.11) when further adjusted for baseline measures of weekly cigarette tobacco and cannabis use. Weaker associations were found for the less demanding 2-back task. We found no evidence to suggest frequent drinking was associated with performance on either task. Conclusions We found weak evidence of an association between sustained heavy alcohol use in mid-adolescence and impaired WM 3 years later. Although we cannot fully rule out the possibility of reverse causation, several potential confounding variables were included to address the directionality of the relationship between WM and alcohol use problems.
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Affiliation(s)
- Liam Mahedy
- Population Health Sciences, Bristol Medical School, University of Bristol, Oakfield Grove, Bristol BS8 2BN, UK
| | - Matt Field
- Department of Psychological Sciences, University of Liverpool, Bedford Street South, Liverpool L69 7ZA, UK.,UK Centre for Tobacco and Alcohol Studies, University of Liverpool, Liverpool, UK
| | - Suzanne Gage
- Department of Psychological Sciences, University of Liverpool, Bedford Street South, Liverpool L69 7ZA, UK
| | - Gemma Hammerton
- Population Health Sciences, Bristol Medical School, University of Bristol, Oakfield Grove, Bristol BS8 2BN, UK
| | - Jon Heron
- Population Health Sciences, Bristol Medical School, University of Bristol, Oakfield Grove, Bristol BS8 2BN, UK
| | - Matt Hickman
- Population Health Sciences, Bristol Medical School, University of Bristol, Oakfield Grove, Bristol BS8 2BN, UK
| | - Marcus R Munafò
- School of Experimental Psychology, University of Bristol, Priory Road, Bristol, BS8 1TU, UK.,MRC Integrative Epidemiology Unit (IEU), University of Bristol, Oakfield Grove, Bristol BS8 2BN, UK.,UK Centre for Tobacco and Alcohol Studies, School of Experimental Psychology, University of Bristol, Priory Road, Bristol BS8 ITU, UK
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32
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Vredeveldt A, Charman SD, den Blanken A, Hooydonk M. Effects of cannabis on eyewitness memory: A field study. APPLIED COGNITIVE PSYCHOLOGY 2018; 32:420-428. [PMID: 30069079 PMCID: PMC6055797 DOI: 10.1002/acp.3414] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 03/14/2018] [Accepted: 03/22/2018] [Indexed: 11/06/2022]
Abstract
Eyewitnesses to crimes are regularly under the influence of drugs, such as cannabis. Yet there is very little research on how the use of cannabis affects eyewitness memory. In the present study, we assessed the effects of cannabis on eyewitness recall and lineup identification performance in a field setting. One hundred twenty visitors of coffee shops in Amsterdam viewed a videotaped criminal event, were interviewed about the event, and viewed a target-present or target-absent lineup. Witnesses under the influence of cannabis remembered significantly fewer correct details about the witnessed event than did sober witnesses, with no difference in incorrect recall. Cannabis use was not significantly associated with lineup identification performance, but intoxicated witnesses were significantly better at judging whether their lineup identification was accurate. Theoretical and practical implications of the findings are discussed.
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Affiliation(s)
- Annelies Vredeveldt
- Department of Criminal Law and Criminology, Faculty of LawVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Steve D. Charman
- Department of PsychologyFlorida International UniversityMiamiUSA
| | - Aukje den Blanken
- Department of Criminal Law and Criminology, Faculty of LawVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Maren Hooydonk
- Department of Criminal Law and Criminology, Faculty of LawVrije Universiteit AmsterdamAmsterdamThe Netherlands
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33
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Cengel HY, Bozkurt M, Evren C, Umut G, Keskinkilic C, Agachanli R. Evaluation of cognitive functions in individuals with synthetic cannabinoid use disorder and comparison to individuals with cannabis use disorder. Psychiatry Res 2018; 262:46-54. [PMID: 29407568 DOI: 10.1016/j.psychres.2018.01.046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 11/26/2017] [Accepted: 01/24/2018] [Indexed: 02/05/2023]
Abstract
The use of synthetic cannabinoid has been increasing throughout the world and has become a major public health problem. The present study aims to investigate the attention, memory, visuospatial and executive functions in individuals with synthetic cannabinoid use disorder and compare the results with findings obtained from individuals with cannabis use disorder and healthy volunteers with no substance use. Fifty-two patients with synthetic cannabinoid use disorder, 45 patients with cannabis use disorder and 48 healthy control group males were included in the study. The neuropsychological test battery was designed to involve ten studies evaluating a large series of cognitive functions. Impairments in attention, memory, executive and visuospatial functions were identified in individuals with synthetic cannabinoid use disorder and these impairments were found to be significantly greater than in individuals with cannabis use disorder and healthy controls. In line with the data obtained from this study; the evaluation of each cognitive function with more comprehensive test batteries and supporting these evaluations with sensitive brain imaging studies are important topics for future research.
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Affiliation(s)
- Hanife Yilmaz Cengel
- Research, Treatment and Training Center for Alcohol and Substance Dependence (AMATEM), Bakirkoy Training and Research Hospital for Psychiatry, Neurology and Neurosurgery, Istanbul, Turkey.
| | - Muge Bozkurt
- Research, Treatment and Training Center for Alcohol and Substance Dependence (AMATEM), Bakirkoy Training and Research Hospital for Psychiatry, Neurology and Neurosurgery, Istanbul, Turkey
| | - Cuneyt Evren
- Research, Treatment and Training Center for Alcohol and Substance Dependence (AMATEM), Bakirkoy Training and Research Hospital for Psychiatry, Neurology and Neurosurgery, Istanbul, Turkey
| | - Gokhan Umut
- Research, Treatment and Training Center for Alcohol and Substance Dependence (AMATEM), Bakirkoy Training and Research Hospital for Psychiatry, Neurology and Neurosurgery, Istanbul, Turkey
| | - Cahit Keskinkilic
- Department of Neuropsychology, Bakirkoy Training and Research Hospital for Psychiatry Neurology and Neurosurgery, Istanbul, Turkey
| | - Ruken Agachanli
- Research, Treatment and Training Center for Alcohol and Substance Dependence (AMATEM), Bakirkoy Training and Research Hospital for Psychiatry, Neurology and Neurosurgery, Istanbul, Turkey
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34
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Blasiman RN, Was CA. Why Is Working Memory Performance Unstable? A Review of 21 Factors. EUROPES JOURNAL OF PSYCHOLOGY 2018; 14:188-231. [PMID: 29899806 PMCID: PMC5973525 DOI: 10.5964/ejop.v14i1.1472] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 08/25/2017] [Indexed: 01/05/2023]
Abstract
In this paper, we systematically reviewed twenty-one factors that have been shown to either vary with or influence performance on working memory (WM) tasks. Specifically, we review previous work on the influence of intelligence, gender, age, personality, mental illnesses/medical conditions, dieting, craving, stress/anxiety, emotion/motivation, stereotype threat, temperature, mindfulness training, practice, bilingualism, musical training, altitude/hypoxia, sleep, exercise, diet, psychoactive substances, and brain stimulation on WM performance. In addition to a review of the literature, we suggest several frameworks for classifying these factors, identify shared mechanisms between several variables, and suggest areas requiring further investigation. This review critically examines the breadth of research investigating WM while synthesizing the results across related subfields in psychology.
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35
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Sherif MA, Cortes-Briones JA, Ranganathan M, Skosnik PD. Cannabinoid-glutamate interactions and neural oscillations: implications for psychosis. Eur J Neurosci 2018; 48:2890-2902. [PMID: 29247465 DOI: 10.1111/ejn.13800] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 12/06/2017] [Accepted: 12/07/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Mohamed A. Sherif
- Department of Psychiatry; Yale University School of Medicine; VA Connecticut Healthcare System Building 5, Suite C-214 950 Campbell Avenue West Haven CT 06516 USA
| | - Jose A. Cortes-Briones
- Department of Psychiatry; Yale University School of Medicine; VA Connecticut Healthcare System Building 5, Suite C-214 950 Campbell Avenue West Haven CT 06516 USA
| | - Mohini Ranganathan
- Department of Psychiatry; Yale University School of Medicine; VA Connecticut Healthcare System Building 5, Suite C-214 950 Campbell Avenue West Haven CT 06516 USA
| | - Patrick D. Skosnik
- Department of Psychiatry; Yale University School of Medicine; VA Connecticut Healthcare System Building 5, Suite C-214 950 Campbell Avenue West Haven CT 06516 USA
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36
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Renard J, Rushlow WJ, Laviolette SR. Effects of Adolescent THC Exposure on the Prefrontal GABAergic System: Implications for Schizophrenia-Related Psychopathology. Front Psychiatry 2018; 9:281. [PMID: 30013490 PMCID: PMC6036125 DOI: 10.3389/fpsyt.2018.00281] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/11/2018] [Indexed: 12/14/2022] Open
Abstract
Marijuana is the most commonly used drug of abuse among adolescents. Considerable clinical evidence supports the hypothesis that adolescent neurodevelopmental exposure to high levels of the principal psychoactive component in marijuana, -delta-9-tetrahydrocanabinol (THC), is associated with a high risk of developing psychiatric diseases, such as schizophrenia later in life. This marijuana-associated risk is believed to be related to increasing levels of THC found within commonly used marijuana strains. Adolescence is a highly vulnerable period for the development of the brain, where the inhibitory GABAergic system plays a pivotal role in the maturation of regulatory control mechanisms in the central nervous system (CNS). Specifically, adolescent neurodevelopment represents a critical period wherein regulatory connectivity between higher-order cortical regions and sub-cortical emotional processing circuits such as the mesolimbic dopamine (DA) system is established. Emerging preclinical evidence demonstrates that adolescent exposure to THC selectively targets schizophrenia-related molecular and neuropharmacological signaling pathways in both cortical and sub-cortical regions, including the prefrontal cortex (PFC) and mesolimbic DA pathway, comprising the ventral tegmental area (VTA) and nucleus accumbens (NAc). Prefrontal cortical GABAergic hypofunction is a key feature of schizophrenia-like neuropsychopathology. This GABAergic hypofunction may lead to the loss of control of the PFC to regulate proper sub-cortical DA neurotransmission, thereby leading to schizophrenia-like symptoms. This review summarizes preclinical evidence demonstrating that reduced prefrontal cortical GABAergic neurotransmission has a critical role in the sub-cortical DAergic dysregulation and schizophrenia-like behaviors observed following adolescent THC exposure.
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Affiliation(s)
- Justine Renard
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Walter J Rushlow
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada.,Department of Psychiatry, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Steven R Laviolette
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada.,Department of Psychiatry, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
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37
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Ruggiero RN, Rossignoli MT, De Ross JB, Hallak JEC, Leite JP, Bueno-Junior LS. Cannabinoids and Vanilloids in Schizophrenia: Neurophysiological Evidence and Directions for Basic Research. Front Pharmacol 2017; 8:399. [PMID: 28680405 PMCID: PMC5478733 DOI: 10.3389/fphar.2017.00399] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/06/2017] [Indexed: 01/14/2023] Open
Abstract
Much of our knowledge of the endocannabinoid system in schizophrenia comes from behavioral measures in rodents, like prepulse inhibition of the acoustic startle and open-field locomotion, which are commonly used along with neurochemical approaches or drug challenge designs. Such methods continue to map fundamental mechanisms of sensorimotor gating, hyperlocomotion, social interaction, and underlying monoaminergic, glutamatergic, and GABAergic disturbances. These strategies will require, however, a greater use of neurophysiological tools to better inform clinical research. In this sense, electrophysiology and viral vector-based circuit dissection, like optogenetics, can further elucidate how exogenous cannabinoids worsen (e.g., tetrahydrocannabinol, THC) or ameliorate (e.g., cannabidiol, CBD) schizophrenia symptoms, like hallucinations, delusions, and cognitive deficits. Also, recent studies point to a complex endocannabinoid-endovanilloid interplay, including the influence of anandamide (endogenous CB1 and TRPV1 agonist) on cognitive variables, such as aversive memory extinction. In fact, growing interest has been devoted to TRPV1 receptors as promising therapeutic targets. Here, these issues are reviewed with an emphasis on the neurophysiological evidence. First, we contextualize imaging and electrographic findings in humans. Then, we present a comprehensive review on rodent electrophysiology. Finally, we discuss how basic research will benefit from further combining psychopharmacological and neurophysiological tools.
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Affiliation(s)
- Rafael N Ruggiero
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Matheus T Rossignoli
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Jana B De Ross
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Jaime E C Hallak
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil.,National Institute for Science and Technology-Translational Medicine, National Council for Scientific and Technological Development (CNPq)Ribeirão Preto, Brazil
| | - Joao P Leite
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
| | - Lezio S Bueno-Junior
- Department of Neuroscience and Behavioral Sciences, Ribeirão Preto Medical School, University of São PauloRibeirão Preto, Brazil
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Abstract
Distracted driving has been identified as a major concern in highway safety. Research to-date, however, has largely focused on distraction related to external events or intentional engagement in non-driving activities. Internal distraction (“mind wandering”) is now being recognized as a significant source of driver distraction that requires rigorous study. There are substantial challenges in detecting, measuring, and addressing mind wandering while driving. Panelists with expertise in driver distraction in general, and mind wandering in particular, will discuss both scientific and pragmatic issues in addressing this problem. Each panelist will present a brief perspective on the problem from the point of view of their experience and expertise. This will be followed by an open discussion period.
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Spronk DB, De Bruijn ERA, van Wel JHP, Ramaekers JG, Verkes RJ. Acute effects of cocaine and cannabis on response inhibition in humans: an ERP investigation. Addict Biol 2016; 21:1186-1198. [PMID: 26037156 DOI: 10.1111/adb.12274] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Substance abuse has often been associated with alterations in response inhibition in humans. Not much research has examined how the acute effects of drugs modify the neurophysiological correlates of response inhibition, or how these effects interact with individual variation in trait levels of impulsivity and novelty seeking. This study investigated the effects of cocaine and cannabis on behavioural and event-related potential (ERP) correlates of response inhibition in 38 healthy drug using volunteers. A double-blind placebo-controlled randomized three-way crossover design was used. All subjects completed a standard Go/NoGo task after administration of the drugs. Compared with a placebo, cocaine yielded improved accuracy, quicker reaction times and an increased prefrontal NoGo-P3 ERP. Cannabis produced opposing results; slower reaction times, impaired accuracy and a reduction in the amplitude of the prefrontal NoGo-P3. Cannabis in addition decreased the amplitude of the parietally recorded P3, while cocaine did not affect this. Neither drugs specifically affected the N2 component, suggesting that pre-motor response inhibitory processes remain unaffected. Neither trait impulsivity nor novelty seeking interacted with drug-induced effects on measures of response inhibition. We conclude that acute drug effects on response inhibition seem to be specific to the later, evaluative stages of response inhibition. The acute effects of cannabis appeared less specific to response inhibition than those of cocaine. Together, the results show that the behavioural effects on response inhibition are reflected in electrophysiological correlates. This study did not support a substantial role of vulnerability personality traits in the acute intoxication stage.
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Affiliation(s)
- Desirée B. Spronk
- Department of Psychiatry; Radboud University Medical Centre; Nijmegen The Netherlands
- Donders Institute for Brain, Cognition and Behaviour; Radboud University Nijmegen; Nijmegen The Netherlands
| | - Ellen R. A. De Bruijn
- Department of Clinical Psychology, Leiden Institute for Brain and Cognition; Leiden University; Leiden The Netherlands
| | - Janelle H. P. van Wel
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience; Maastricht University; Maastricht The Netherlands
| | - Johannes G. Ramaekers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience; Maastricht University; Maastricht The Netherlands
| | - Robbert J. Verkes
- Department of Psychiatry; Radboud University Medical Centre; Nijmegen The Netherlands
- Donders Institute for Brain, Cognition and Behaviour; Radboud University Nijmegen; Nijmegen The Netherlands
- Pompestichting for Forensic Psychiatry; Nijmegen The Netherlands
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Sherif M, Radhakrishnan R, D'Souza DC, Ranganathan M. Human Laboratory Studies on Cannabinoids and Psychosis. Biol Psychiatry 2016; 79:526-38. [PMID: 26970363 DOI: 10.1016/j.biopsych.2016.01.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 01/14/2016] [Accepted: 01/14/2016] [Indexed: 10/22/2022]
Abstract
Some of the most compelling evidence supporting an association between cannabinoid agonists and psychosis comes from controlled laboratory studies in humans. Randomized, double-blind, placebo-controlled, crossover laboratory studies demonstrate that cannabinoid agonists, including phytocannabinoids and synthetic cannabinoids, produce a wide range of positive, negative, and cognitive symptoms and psychophysiologic deficits in healthy human subjects that resemble the phenomenology of schizophrenia. These effects are time locked to drug administration, are dose related, and are transient and rarely necessitate intervention. The magnitude of effects is similar to the effects of ketamine but qualitatively distinct from other psychotomimetic drugs, including ketamine, amphetamine, and salvinorin A. Cannabinoid agonists have also been shown to transiently exacerbate symptoms in individuals with schizophrenia in laboratory studies. Patients with schizophrenia are more vulnerable than healthy control subjects to the acute behavioral and cognitive effects of cannabinoid agonists and experience transient exacerbation of symptoms despite treatment with antipsychotic medications. Furthermore, laboratory studies have failed to demonstrate any "beneficial" effects of cannabinoid agonists in individuals with schizophrenia-challenging the cannabis self-medication hypothesis. Emerging evidence suggests that polymorphisms of several genes related to dopamine metabolism (e.g., COMT, DAT1, and AKT1) may moderate the effects of cannabinoid agonists in laboratory studies. Cannabinoid agonists induce dopamine release, although the magnitude of release does not appear to be commensurate to the magnitude and spectrum of their acute psychotomimetic effects. Interactions between the endocannabinoid, gamma-aminobutyric acid, and glutamate systems and their individual and interactive effects on neural oscillations provide a plausible mechanism underlying the psychotomimetic effects of cannabinoids.
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Affiliation(s)
- Mohamed Sherif
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Rajiv Radhakrishnan
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Deepak Cyril D'Souza
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Mohini Ranganathan
- Schizophrenia and Neuropharmacology Research Group, VA Connecticut Healthcare System, West Haven; Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, New Haven, Connecticut; Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut.
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Skosnik PD, Cortes-Briones JA, Hajós M. It's All in the Rhythm: The Role of Cannabinoids in Neural Oscillations and Psychosis. Biol Psychiatry 2016; 79:568-77. [PMID: 26850792 DOI: 10.1016/j.biopsych.2015.12.011] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 11/04/2015] [Accepted: 12/03/2015] [Indexed: 02/08/2023]
Abstract
Evidence has accumulated over the past several decades suggesting that both exocannabinoids and endocannabinoids play a role in the pathophysiology of schizophrenia. The current article presents evidence suggesting that one of the mechanisms whereby cannabinoids induce psychosis is through the alteration in synchronized neural oscillations. Neural oscillations, particularly in the gamma (30-80 Hz) and theta (4-7 Hz) ranges, are disrupted in schizophrenia and are involved in various areas of perceptual and cognitive function. Regarding cannabinoids, preclinical evidence from slice and local field potential recordings has shown that central cannabinoid receptor (cannabinoid receptor type 1) agonists decrease the power of neural oscillations, particularly in the gamma and theta bands. Further, the administration of cannabinoids during critical stages of neural development has been shown to disrupt the brain's ability to generate synchronized neural oscillations in adulthood. In humans, studies examining the effects of chronic cannabis use (utilizing electroencephalography) have shown abnormalities in neural oscillations in a pattern similar to those observed in schizophrenia. Finally, recent studies in humans have also shown disruptions in neural oscillations after the acute administration of delta-9-tetrahydrocannabinol, the primary psychoactive constituent in cannabis. Taken together, these data suggest that both acute and chronic cannabinoids can disrupt the ability of the brain to generate synchronized oscillations at functionally relevant frequencies. Hence, this may represent one of the primary mechanisms whereby cannabinoids induce disruptions in attention, working memory, sensory-motor integration, and many other psychosis-related behavioral effects.
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Affiliation(s)
- Patrick D Skosnik
- Department of Psychiatry, Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut.
| | - Jose A Cortes-Briones
- Department of Psychiatry, Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Mihály Hajós
- Laboratory of Translational Neuropharmacology, Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut
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Euler MJ, Wiltshire TJ, Niermeyer MA, Butner JE. Working memory performance inversely predicts spontaneous delta and theta-band scaling relations. Brain Res 2016; 1637:22-33. [DOI: 10.1016/j.brainres.2016.02.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/05/2016] [Accepted: 02/02/2016] [Indexed: 10/22/2022]
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Fetterhoff D, Kraft RA, Sandler RA, Opris I, Sexton CA, Marmarelis VZ, Hampson RE, Deadwyler SA. Distinguishing cognitive state with multifractal complexity of hippocampal interspike interval sequences. Front Syst Neurosci 2015; 9:130. [PMID: 26441562 PMCID: PMC4585000 DOI: 10.3389/fnsys.2015.00130] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 09/03/2015] [Indexed: 11/15/2022] Open
Abstract
Fractality, represented as self-similar repeating patterns, is ubiquitous in nature and the brain. Dynamic patterns of hippocampal spike trains are known to exhibit multifractal properties during working memory processing; however, it is unclear whether the multifractal properties inherent to hippocampal spike trains reflect active cognitive processing. To examine this possibility, hippocampal neuronal ensembles were recorded from rats before, during and after a spatial working memory task following administration of tetrahydrocannabinol (THC), a memory-impairing component of cannabis. Multifractal detrended fluctuation analysis was performed on hippocampal interspike interval sequences to determine characteristics of monofractal long-range temporal correlations (LRTCs), quantified by the Hurst exponent, and the degree/magnitude of multifractal complexity, quantified by the width of the singularity spectrum. Our results demonstrate that multifractal firing patterns of hippocampal spike trains are a marker of functional memory processing, as they are more complex during the working memory task and significantly reduced following administration of memory impairing THC doses. Conversely, LRTCs are largest during resting state recordings, therefore reflecting different information compared to multifractality. In order to deepen conceptual understanding of multifractal complexity and LRTCs, these measures were compared to classical methods using hippocampal frequency content and firing variability measures. These results showed that LRTCs, multifractality, and theta rhythm represent independent processes, while delta rhythm correlated with multifractality. Taken together, these results provide a novel perspective on memory function by demonstrating that the multifractal nature of spike trains reflects hippocampal microcircuit activity that can be used to detect and quantify cognitive, physiological, and pathological states.
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Affiliation(s)
- Dustin Fetterhoff
- Neuroscience Program, Wake Forest School of Medicine Winston-Salem, NC, USA ; Department of Physiology and Pharmacology, Wake Forest School of Medicine Winston-Salem, NC, USA
| | - Robert A Kraft
- Department of Biomedical Engineering, Wake Forest School of Medicine Winston-Salem, NC, USA
| | - Roman A Sandler
- Department of Biomedical Engineering, University of Southern California Los Angeles, CA, USA
| | - Ioan Opris
- Department of Physiology and Pharmacology, Wake Forest School of Medicine Winston-Salem, NC, USA
| | - Cheryl A Sexton
- Department of Biomedical Engineering, Wake Forest School of Medicine Winston-Salem, NC, USA
| | - Vasilis Z Marmarelis
- Department of Biomedical Engineering, University of Southern California Los Angeles, CA, USA
| | - Robert E Hampson
- Department of Physiology and Pharmacology, Wake Forest School of Medicine Winston-Salem, NC, USA
| | - Sam A Deadwyler
- Department of Physiology and Pharmacology, Wake Forest School of Medicine Winston-Salem, NC, USA
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Baron EP. Comprehensive Review of Medicinal Marijuana, Cannabinoids, and Therapeutic Implications in Medicine and Headache: What a Long Strange Trip It's Been …. Headache 2015; 55:885-916. [PMID: 26015168 DOI: 10.1111/head.12570] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND The use of cannabis, or marijuana, for medicinal purposes is deeply rooted though history, dating back to ancient times. It once held a prominent position in the history of medicine, recommended by many eminent physicians for numerous diseases, particularly headache and migraine. Through the decades, this plant has taken a fascinating journey from a legal and frequently prescribed status to illegal, driven by political and social factors rather than by science. However, with an abundance of growing support for its multitude of medicinal uses, the misguided stigma of cannabis is fading, and there has been a dramatic push for legalizing medicinal cannabis and research. Almost half of the United States has now legalized medicinal cannabis, several states have legalized recreational use, and others have legalized cannabidiol-only use, which is one of many therapeutic cannabinoids extracted from cannabis. Physicians need to be educated on the history, pharmacology, clinical indications, and proper clinical use of cannabis, as patients will inevitably inquire about it for many diseases, including chronic pain and headache disorders for which there is some intriguing supportive evidence. OBJECTIVE To review the history of medicinal cannabis use, discuss the pharmacology and physiology of the endocannabinoid system and cannabis-derived cannabinoids, perform a comprehensive literature review of the clinical uses of medicinal cannabis and cannabinoids with a focus on migraine and other headache disorders, and outline general clinical practice guidelines. CONCLUSION The literature suggests that the medicinal use of cannabis may have a therapeutic role for a multitude of diseases, particularly chronic pain disorders including headache. Supporting literature suggests a role for medicinal cannabis and cannabinoids in several types of headache disorders including migraine and cluster headache, although it is primarily limited to case based, anecdotal, or laboratory-based scientific research. Cannabis contains an extensive number of pharmacological and biochemical compounds, of which only a minority are understood, so many potential therapeutic uses likely remain undiscovered. Cannabinoids appear to modulate and interact at many pathways inherent to migraine, triptan mechanisms ofaction, and opiate pathways, suggesting potential synergistic or similar benefits. Modulation of the endocannabinoid system through agonism or antagonism of its receptors, targeting its metabolic pathways, or combining cannabinoids with other analgesics for synergistic effects, may provide the foundation for many new classes of medications. Despite the limited evidence and research suggesting a role for cannabis and cannabinoids in some headache disorders, randomized clinical trials are lacking and necessary for confirmation and further evaluation.
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Affiliation(s)
- Eric P Baron
- Department of Neurology, Headache Center, Cleveland Clinic Neurological Institute, Cleveland, OH, USA
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Desrosiers NA, Ramaekers JG, Chauchard E, Gorelick DA, Huestis MA. Smoked cannabis' psychomotor and neurocognitive effects in occasional and frequent smokers. J Anal Toxicol 2015; 39:251-61. [PMID: 25745105 DOI: 10.1093/jat/bkv012] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Δ9-Tetrahydrocannabinol (THC), the primary psychoactive constituent in cannabis, impairs psychomotor performance, cognition and driving ability; thus, driving under the influence of cannabis is a public safety concern. We documented cannabis' psychomotor, neurocognitive, subjective and physiological effects in occasional and frequent smokers to investigate potential differences between these smokers. Fourteen frequent (≥4x/week) and 11 occasional (<2x/week) cannabis smokers entered a secure research unit ∼19 h prior to smoking one 6.8% THC cigarette. Cognitive and psychomotor performance was evaluated with the critical tracking (CTT), divided attention (DAT), n-back (working memory) and Balloon Analog Risk (BART) (risk-taking) tasks at -1.75, 1.5, 3.5, 5.5 and 22.5 h after starting smoking. GLM (General Linear Model) repeated measures ANOVA was utilized to compare scores. Occasional smokers had significantly more difficulty compensating for CTT tracking error compared with frequent smokers 1.5 h after smoking. Divided attention performance declined significantly especially in occasional smokers, with session × group effects for tracking error, hits, false alarms and reaction time. Cannabis smoking did not elicit session × group effects on the n-back or BART. Controlled cannabis smoking impaired psychomotor function, more so in occasional smokers, suggesting some tolerance to psychomotor impairment in frequent users. These data have implications for cannabis-associated impairment in driving under the influence of cannabis cases.
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Affiliation(s)
- Nathalie A Desrosiers
- Chemistry and Drug Metabolism Section, Clinical Pharmacology and Therapeutic Research Branch, NIDA IRP, 251 Bayview Boulevard, Suite 200 Room 05A-721, Baltimore, MD 21224, USA Program in Toxicology, University of Maryland Baltimore, Baltimore, MD, USA
| | - Johannes G Ramaekers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Emeline Chauchard
- Chemistry and Drug Metabolism Section, Clinical Pharmacology and Therapeutic Research Branch, NIDA IRP, 251 Bayview Boulevard, Suite 200 Room 05A-721, Baltimore, MD 21224, USA Present address: Laboratoire de Psychologie des Pays de la Loire, Faculté de Psychologie, Université de Nantes, Nantes, France
| | - David A Gorelick
- Chemistry and Drug Metabolism Section, Clinical Pharmacology and Therapeutic Research Branch, NIDA IRP, 251 Bayview Boulevard, Suite 200 Room 05A-721, Baltimore, MD 21224, USA Present address: Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Marilyn A Huestis
- Chemistry and Drug Metabolism Section, Clinical Pharmacology and Therapeutic Research Branch, NIDA IRP, 251 Bayview Boulevard, Suite 200 Room 05A-721, Baltimore, MD 21224, USA
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Developmentally vitamin D-deficient rats show enhanced prepulse inhibition after acute Δ9-tetrahydrocannabinol. Behav Pharmacol 2014; 25:236-44. [PMID: 24776491 DOI: 10.1097/fbp.0000000000000041] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Developmental vitamin D (DVD) deficiency has been proposed as a risk factor for schizophrenia. DVD-deficient rats show selective cognitive deficits and novelty-induced hyperlocomotion and enhanced locomotor responses from acute treatment with psychomimetic drugs, such as amphetamine and MK-801. Here we aimed to examine the effect of a drug from a different class of psychomimetic/psychoactive compounds, Δ9-tetrahydrocannabinol (THC), on tasks of relevance to the cognitive and positive symptoms of schizophrenia. The aim of this study was to investigate whether DVD deficiency modulates the behavioural effects of THC on tests of delay-dependent memory, sensorimotor gating and locomotion. Adult control and DVD-deficient rats were injected with THC (0, 0.3, 0.6, 1.25, 2.5 mg/kg) 15 min before a delay match to sample (DMTS) task using variable delays (0-24 s). A separate group of rats was injected with either 2.5 mg/kg THC or vehicle before tests of either prepulse inhibition (PPI) of the acoustic startle response or in the open field. Control and DVD-deficient rats showed a similar dose-dependent impairment in performance on the DMTS. The greatest impairment was observed at 2.5 mg/kg for all delays (0-24 s). DVD-deficient rats showed THC-induced enhancement of PPI, which was not observed in control rats. There was no effect of maternal diet on acoustic startle response or locomotor responses in the open field. This study reports the novel findings that DVD-deficient rats were more sensitive to the acute effects of THC on PPI. It appears that prenatal vitamin D deficiency has long-term effects on sensitivity to the behavioural effects of cannabinoids.
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47
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Lubman DI, Cheetham A, Yücel M. Cannabis and adolescent brain development. Pharmacol Ther 2014; 148:1-16. [PMID: 25460036 DOI: 10.1016/j.pharmthera.2014.11.009] [Citation(s) in RCA: 189] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 11/03/2014] [Indexed: 12/14/2022]
Abstract
Heavy cannabis use has been frequently associated with increased rates of mental illness and cognitive impairment, particularly amongst adolescent users. However, the neurobiological processes that underlie these associations are still not well understood. In this review, we discuss the findings of studies examining the acute and chronic effects of cannabis use on the brain, with a particular focus on the impact of commencing use during adolescence. Accumulating evidence from both animal and human studies suggests that regular heavy use during this period is associated with more severe and persistent negative outcomes than use during adulthood, suggesting that the adolescent brain may be particularly vulnerable to the effects of cannabis exposure. As the endocannabinoid system plays an important role in brain development, it is plausible that prolonged use during adolescence results in a disruption in the normative neuromaturational processes that occur during this period. We identify synaptic pruning and white matter development as two processes that may be adversely impacted by cannabis exposure during adolescence. Potentially, alterations in these processes may underlie the cognitive and emotional deficits that have been associated with regular use commencing during adolescence.
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Affiliation(s)
- Dan I Lubman
- Turning Point, Eastern Health and Eastern Health Clinical School, Monash University, Victoria, Australia.
| | - Ali Cheetham
- Turning Point, Eastern Health and Eastern Health Clinical School, Monash University, Victoria, Australia
| | - Murat Yücel
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria, Australia; Monash Clinical & Imaging Neuroscience, School of Psychological Sciences, Monash University, Melbourne, Victoria, Australia
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48
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Heitland I, Kenemans JL, Böcker KBE, Baas JMP. Genetic variability in the human cannabinoid receptor 1 is associated with resting state EEG theta power in humans. Behav Brain Res 2014; 274:344-8. [PMID: 25116250 DOI: 10.1016/j.bbr.2014.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 07/31/2014] [Accepted: 08/03/2014] [Indexed: 01/10/2023]
Abstract
It has long been postulated that exogenous cannabinoids have a profound effect on human cognitive functioning. These cannabinoid effects are thought to depend, at least in parts, on alterations of phase-locking of local field potential neuronal firing. The latter can be measured as activity in the theta frequency band (4-7Hz) by electroencephalogram. Theta oscillations are supposed to serve as a mechanism in neural representations of behaviorally relevant information. However, it remains unknown whether variability in endogenous cannabinoid activity is involved in theta rhythms and therefore, may serve as an individual differences index of human cognitive functioning. To clarify this issue, we recorded resting state EEG activity in 164 healthy human subjects and extracted EEG power across frequency bands (δ, θ, α, and β). To assess variability in the endocannabinoid system, two genetic polymorphisms (rs1049353, rs2180619) within the cannabinoid receptor 1 (CB1) were determined in all participants. As expected, we observed significant effects of rs1049353 on EEG power in the theta band at frontal, central and parietal electrode regions. Crucially, these effects were specific for the theta band, with no effects on activity in the other frequency bands. Rs2180619 showed no significant associations with theta power after Bonferroni correction. Taken together, we provide novel evidence in humans showing that genetic variability in the cannabinoid receptor 1 is associated with resting state EEG power in the theta frequency band. This extends prior findings of exogenous cannabinoid effects on theta power to the endogenous cannabinoid system.
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Affiliation(s)
- I Heitland
- Department of Experimental Psychology & Psychopharmacology, Utrecht University, Heidelberglaan 1, 3584CS Utrecht, The Netherlands; Helmholtz Research Institute, Utrecht, The Netherlands.
| | - J L Kenemans
- Department of Experimental Psychology & Psychopharmacology, Utrecht University, Heidelberglaan 1, 3584CS Utrecht, The Netherlands; Helmholtz Research Institute, Utrecht, The Netherlands
| | - K B E Böcker
- Alan Turing Institute Almere, Almere, The Netherlands
| | - J M P Baas
- Department of Experimental Psychology & Psychopharmacology, Utrecht University, Heidelberglaan 1, 3584CS Utrecht, The Netherlands; Helmholtz Research Institute, Utrecht, The Netherlands
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Multifractal analysis of information processing in hippocampal neural ensembles during working memory under Δ⁹-tetrahydrocannabinol administration. J Neurosci Methods 2014; 244:136-53. [PMID: 25086297 DOI: 10.1016/j.jneumeth.2014.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 06/06/2014] [Accepted: 07/16/2014] [Indexed: 12/22/2022]
Abstract
BACKGROUND Multifractal analysis quantifies the time-scale-invariant properties in data by describing the structure of variability over time. By applying this analysis to hippocampal interspike interval sequences recorded during performance of a working memory task, a measure of long-range temporal correlations and multifractal dynamics can reveal single neuron correlates of information processing. NEW METHOD Wavelet leaders-based multifractal analysis (WLMA) was applied to hippocampal interspike intervals recorded during a working memory task. WLMA can be used to identify neurons likely to exhibit information processing relevant to operation of brain-computer interfaces and nonlinear neuronal models. RESULTS Neurons involved in memory processing ("Functional Cell Types" or FCTs) showed a greater degree of multifractal firing properties than neurons without task-relevant firing characteristics. In addition, previously unidentified FCTs were revealed because multifractal analysis suggested further functional classification. The cannabinoid type-1 receptor (CB1R) partial agonist, tetrahydrocannabinol (THC), selectively reduced multifractal dynamics in FCT neurons compared to non-FCT neurons. COMPARISON WITH EXISTING METHODS WLMA is an objective tool for quantifying the memory-correlated complexity represented by FCTs that reveals additional information compared to classification of FCTs using traditional z-scores to identify neuronal correlates of behavioral events. CONCLUSION z-Score-based FCT classification provides limited information about the dynamical range of neuronal activity characterized by WLMA. Increased complexity, as measured with multifractal analysis, may be a marker of functional involvement in memory processing. The level of multifractal attributes can be used to differentially emphasize neural signals to improve computational models and algorithms underlying brain-computer interfaces.
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50
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Bossong MG, Jansma JM, Bhattacharyya S, Ramsey NF. Role of the endocannabinoid system in brain functions relevant for schizophrenia: an overview of human challenge studies with cannabis or ∆9-tetrahydrocannabinol (THC). Prog Neuropsychopharmacol Biol Psychiatry 2014; 52:53-69. [PMID: 24380726 DOI: 10.1016/j.pnpbp.2013.11.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 10/16/2013] [Accepted: 11/25/2013] [Indexed: 12/30/2022]
Abstract
Accumulating evidence suggests involvement of the endocannabinoid system in the pathophysiology of schizophrenia, which signifies a potential application for this system in the treatment of this disorder. However, before new research can focus on potential treatments that work by manipulating the endocannabinoid system, it needs to be elucidated how this system is involved in symptoms of schizophrenia. Here we review human studies that investigated acute effects of cannabis or ∆9-tetrahydrocannabinol (THC) on brain functions that are implicated in schizophrenia. Results suggest that the impact of THC administration depends on the difficulty of the task performed. Impaired performance of cognitive paradigms is reported on more challenging tasks, which is associated with both activity deficits in temporal and prefrontal areas and a failure to deactivate regions of the default mode network. Comparable reductions in prefrontal activity and impairments in deactivation of the default mode network are seen in patients during performance of cognitive paradigms. Normal performance levels after THC administration demonstrated for less demanding tasks are shown to be related to either increased neural effort in task-specific regions ('neurophysiological inefficiency'), or recruitment of alternative brain areas, which suggests a change in strategy to meet cognitive demands. Particularly a pattern of performance and brain activity corresponding with an inefficient working memory system is consistently demonstrated in patients. These similarities in brain function between intoxicated healthy volunteers and schizophrenia patients provide an argument for a role of the endocannabinoid system in symptoms of schizophrenia, and further emphasize this system as a potential novel target for treatment of these symptoms.
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Affiliation(s)
- Matthijs G Bossong
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom.
| | - J Martijn Jansma
- Rudolf Magnus Institute of Neuroscience, Department of Neurology and Neurosurgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Sagnik Bhattacharyya
- Institute of Psychiatry, Department of Psychosis Studies, King's College London, 16 De Crespigny Park, London SE5 8AF, United Kingdom
| | - Nick F Ramsey
- Rudolf Magnus Institute of Neuroscience, Department of Neurology and Neurosurgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
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