Methods of the Pharmacological Imaging of the Cannabinoid System (PhICS) study: towards understanding the role of the brain endocannabinoid system in human cognition

IntroductionAlthough cannabis is very widespread worldwide, its brain toxicity is poorly understood. The neuroretina is an accessible extension of the brain and could be a relevant site for investigating neurotransmission abnormalities in neuropsychiatric disorders. The retina has a functional endocannabinoid system involved in the regulation of retinal neurotransmission. In animals, the modulation of this system led to retinal dysfunctions measured with the electroretinogram (ERG).ObjectivesTo assess whether the regular cannabis use could affect the neuroretinal function.AimsAssessments of the neuroretinal function in cannabis users compared with controls.MethodsRecordings of pattern, flash and on-off ERG were performed in 55 cannabis users and 29 controls. The amplitude and implicit time of the following waves were evaluated: N95 (pattern); a – and b – (flash); a –, b- and d1 – (on-off).ResultsCannabis users showed a significant increase in implicit time of the waves N95 (P = 0.0001), a- (P = 0.029) and b – (P = 0.002) for the flash ERG and b – (P = 0.016) and d1 – (P = 0.027) for the on-off ERG, compared with controls. No significant difference was found between groups in terms of wave's amplitudes.ConclusionsThese results show a delay in the response of cones, bipolar and ganglion cells of the on and off pathways to constitute a delay of ≈ 6 ms in the transmission of information from the retina to the brain in cannabis users. Cannabis could disrupt the regulatory role of the cannabinoid system and impair retinal glutamatergic neurotransmission. The consequences on visual perception should be explored in future studies.Disclosure of interestThe authors have not supplied their declaration of competing interest.

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The Role of the Endocannabinoid System in the Brain–Gut Axis

Gastroenterology ◽

10.1053/j.gastro.2016.04.015 ◽

2016 ◽

Vol 151 (2) ◽

pp. 252-266 ◽

Cited By ~ 61

Author(s):

Keith A. Sharkey ◽

John W. Wiley

Keyword(s):

Endocannabinoid System ◽

The Brain

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Atmosphere, affordances, and emotion

10.1093/med/9780190060954.003.0004 ◽

2021 ◽

pp. 221-286

Author(s):

Michael A. Arbib

Keyword(s):

Mental Image ◽

Visual Pathway ◽

Human Cognition ◽

Fmri Study ◽

Whole Person ◽

Key Variables ◽

The Brain ◽

Person Experience ◽

Over Time

The atmosphere of a building is the pervading mood it provides, and can be considered a non-Gibsonian affordance. Atmosphere may frame our experience of a building, but over time our perception of the atmosphere may change. This chapter explores atmosphere in relation to motivation and emotion and the role of the limbic system of the brain. Emotion builds on a set of primordial emotions, but human cognition adds subtlety and supports aesthetic emotions. Paintings by Turner and Constable are examined to take the reader beyond the phenomenology of atmosphere and to explore the idea that the artist “inverts” vision. A visual pathway judges the emerging sketch; a visuomotor pathway updates the sketch. In iterating the process, the sketch changes, but so too will the mental image. An fMRI study of architects observing images of “contemplative” building grounds a critique that suggests challenges for designing further experiments. A crucial obstacle is the distance between cog/neuroscience experiments that seek to isolate the influence of a few key variables and the whole-person experience of using and contemplating a building in all its varied complexity.

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The endocannabinoid system in normal and pathological brain ageing

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2011.0388 ◽

2012 ◽

Vol 367 (1607) ◽

pp. 3326-3341 ◽

Cited By ~ 59

Author(s):

Andras Bilkei-Gorzo

Keyword(s):

Molecular Mechanisms ◽

Endocannabinoid System ◽

System Level ◽

Mitochondrial Activity ◽

Normal Brain ◽

Neuroprotective Effects ◽

Cannabinoid System ◽

Age Related ◽

Brain Ageing

The role of endocannabinoids as inhibitory retrograde transmitters is now widely known and intensively studied. However, endocannabinoids also influence neuronal activity by exerting neuroprotective effects and regulating glial responses. This review centres around this less-studied area, focusing on the cellular and molecular mechanisms underlying the protective effect of the cannabinoid system in brain ageing. The progression of ageing is largely determined by the balance between detrimental, pro-ageing, largely stochastic processes, and the activity of the homeostatic defence system. Experimental evidence suggests that the cannabinoid system is part of the latter system. Cannabinoids as regulators of mitochondrial activity, as anti-oxidants and as modulators of clearance processes protect neurons on the molecular level. On the cellular level, the cannabinoid system regulates the expression of brain-derived neurotrophic factor and neurogenesis. Neuroinflammatory processes contributing to the progression of normal brain ageing and to the pathogenesis of neurodegenerative diseases are suppressed by cannabinoids, suggesting that they may also influence the ageing process on the system level. In good agreement with the hypothesized beneficial role of cannabinoid system activity against brain ageing, it was shown that animals lacking CB1 receptors show early onset of learning deficits associated with age-related histological and molecular changes. In preclinical models of neurodegenerative disorders, cannabinoids show beneficial effects, but the clinical evidence regarding their efficacy as therapeutic tools is either inconclusive or still missing.

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Cannabidiolɗs Role as a Potential Target in the Treatment for Schizophrenia

European Psychiatry ◽

10.1016/j.eurpsy.2017.01.1028 ◽

2017 ◽

Vol 41 (S1) ◽

pp. S631-S631

Author(s):

A. Carvalho ◽

J. Felgueiras ◽

T. Abreu ◽

C. Freitas ◽

J. Silva

Keyword(s):

Endocannabinoid System ◽

Brain Regions ◽

Great Promise ◽

Novel Therapy ◽

Considerable Uncertainty ◽

Wide Range ◽

Competing Interest ◽

The Individual ◽

The Brain

ObjectivesSchizophrenia is a debilitating psychiatric disorder which places a significant emotional and economic strain on the individual and society-at-large. Unfortunately, currently available therapeutic strategies do not provide adequate relief and some patients are treatment-resistant. Therefore there is urgent need for the development of mechanistically different and less side effect prone antipsychotic compounds. Recently, the endocannabinoid system has emerged as a potential therapeutic target for pharmacotherapy that is involved in a wide range of disorders, including schizophrenia. Modulation of this system by the main psychoactive component in cannabis, Δ9tetrahydrocannabinol (THC), induces acute psychotic effects and cognitive impairment. However, the non-psychotropic, plant-derived cannabinoid agent cannabidiol shows great promise for the treatment of psychosis, and is associated with fewer extrapyramidal side effects than conventional antipsychotic drugs.MethodsThe aim of this review is to analyse the involvement of the endocannabinoid system in schizophrenia and the potential role of cannabidiol in its treatment.Results and conclusionsThere is still considerable uncertainty about the mechanism of action of cannabidiol as well as the brain regions which are thought to mediate its putative antipsychotic effect. Further data is warrant before this novel therapy can be introduced into clinical practice.Disclosure of interestThe authors have not supplied their declaration of competing interest

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Cognitive Processes Involved in Visual Thought

Perceptions of Knowledge Visualization - Advances in Multimedia and Interactive Technologies ◽

10.4018/978-1-4666-4703-9.ch005 ◽

2014 ◽

pp. 131-173

Keyword(s):

Creative Thinking ◽

Higher Order Thinking ◽

Thinking Skills ◽

Visual Development ◽

Human Cognition ◽

Higher Order Thinking Skills ◽

Multiple Intelligences Theory ◽

Visual Intelligence ◽

The Brain

Cognitive thinking is discussed here in terms of processes involved in visual thought and visual problem solving. This chapter recapitulates basic information about human cognition, cognitive structures, and perceptual learning in relation to visual thought. It tells about some ideas in cognitive science, cognitive functions in specific parts of the brain, reviews ideas about thinking visually and verbally, critical versus creative thinking, components of creative performance, mental imagery, visual reasoning, and mental images. Imagery and memory, visual intelligence, visual intelligence tests, and multiple intelligences theory make further parts of the chapter. This is followed by some comments on cognitive development, higher order thinking skills, visual development of a child, the meaning of student art in the course of visual development, and the role of computer graphics in visual development.

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Endocannabinoid System Alterations in Posttraumatic Stress Disorder: A Review of Developmental and Accumulative Effects of Trauma

Chronic Stress ◽

10.1177/2470547019864096 ◽

2019 ◽

Vol 3 ◽

pp. 247054701986409 ◽

Cited By ~ 1

Author(s):

Anahita Bassir Nia ◽

Ricci Bender ◽

Ilan Harpaz-Rotem

Keyword(s):

Sex Differences ◽

Cannabinoid Receptors ◽

Stress Disorder ◽

Psychiatric Symptoms ◽

Endocannabinoid System ◽

Developmental Age ◽

Preclinical And Clinical Studies ◽

Prolonged Stress ◽

The Brain

The role of the endocannabinoid system in stress-related psychiatric symptoms has been investigated in many animal and human studies. Although most of these studies consistently report long-lasting effects of prolonged stress and trauma on the endocannabinoid system, the nature and direction of these changes are controversial. We reviewed the available preclinical and clinical studies investigating the endocannabinoid system alterations long after chronic stress and trauma. We propose that the effects of prolonged stress or trauma on the endocannabinoid system are different based on the developmental age of subjects at the time of experiencing the trauma and its repetitiveness and accumulative effects. The current literature consistently demonstrates decreased levels of endocannabinoid ligands and receptors if the trauma occurs in childhood, whereas decreased levels of endocannabinoid ligands and increased levels of cannabinoid receptors are reported when trauma has happened in adulthood. It is important to note that these changes are region-specific in the brain and also there are important sex differences, which are beyond the scope of this review.

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The Emerging Role of the Endocannabinoid System in Endocrine Regulation and Energy Balance

Endocrine Reviews ◽

10.1210/er.2005-0009 ◽

2005 ◽

Vol 27 (1) ◽

pp. 73-100 ◽

Cited By ~ 546

Author(s):

Uberto Pagotto ◽

Giovanni Marsicano ◽

Daniela Cota ◽

Beat Lutz ◽

Renato Pasquali

Keyword(s):

Energy Balance ◽

Food Intake ◽

Cannabinoid Receptors ◽

Endocannabinoid System ◽

Cb1 Receptor ◽

Endocrine Regulation ◽

Cb2 Receptor ◽

Peripheral Tissues ◽

The Brain

During the last few years, the endocannabinoid system has emerged as a highly relevant topic in the scientific community. Many different regulatory actions have been attributed to endocannabinoids, and their involvement in several pathophysiological conditions is under intense scrutiny. Cannabinoid receptors, named CB1 receptor and CB2 receptor, first discovered as the molecular targets of the psychotropic component of the plant Cannabis sativa, participate in the physiological modulation of many central and peripheral functions. CB2 receptor is mainly expressed in immune cells, whereas CB1 receptor is the most abundant G protein-coupled receptor expressed in the brain. CB1 receptor is expressed in the hypothalamus and the pituitary gland, and its activation is known to modulate all the endocrine hypothalamic-peripheral endocrine axes. An increasing amount of data highlights the role of the system in the stress response by influencing the hypothalamic-pituitary-adrenal axis and in the control of reproduction by modifying gonadotropin release, fertility, and sexual behavior. The ability of the endocannabinoid system to control appetite, food intake, and energy balance has recently received great attention, particularly in the light of the different modes of action underlying these functions. The endocannabinoid system modulates rewarding properties of food by acting at specific mesolimbic areas in the brain. In the hypothalamus, CB1 receptor and endocannabinoids are integrated components of the networks controlling appetite and food intake. Interestingly, the endocannabinoid system was recently shown to control metabolic functions by acting on peripheral tissues, such as adipocytes, hepatocytes, the gastrointestinal tract, and, possibly, skeletal muscle. The relevance of the system is further strenghtened by the notion that drugs interfering with the activity of the endocannabinoid system are considered as promising candidates for the treatment of various diseases, including obesity.

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The Role of Mitochondria in the Genesis of Neuroaxonal Dystrophy in the Brains of Aging Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115481 ◽

1975 ◽

Vol 33 ◽

pp. 372-373

Author(s):

J.E. Johnson

Keyword(s):

Electron Microscopy ◽

Present Report ◽

Light And Electron Microscopy ◽

Dorsal Column ◽

Neuroaxonal Dystrophy ◽

Nucleus Gracilis ◽

Dystrophic Axons ◽

The Brain ◽

Nucleus Cuneatus

Although neuroaxonal dystrophy (NAD) has been examined by light and electron microscopy for years, the nature of the components in the dystrophic axons is not well understood. The present report examines nucleus gracilis and cuneatus (the dorsal column nuclei) in the brain stem of aging mice.Mice (C57BL/6J) were sacrificed by aldehyde perfusion at ages ranging from 3 months to 23 months. Several brain areas and parts of other organs were processed for electron microscopy.At 3 months of age, very little evidence of NAD can be discerned by light microscopy. At the EM level, a few axons are found to contain dystrophic material. By 23 months of age, the entire nucleus gracilis is filled with dystrophic axons. Much less NAD is seen in nucleus cuneatus by comparison. The most recurrent pattern of NAD is an enlarged profile, in the center of which is a mass of reticulated material (reticulated portion; or RP).

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