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https://www.readbyqxmd.com/read/29116367/double-blind-comparison-of-the-two-hallucinogens-psilocybin-and-dextromethorphan-similarities-and-differences-in-subjective-experiences
#1
Theresa M Carbonaro, Matthew W Johnson, Ethan Hurwitz, Roland R Griffiths
RATIONALE: Although psilocybin and dextromethorphan (DXM) are hallucinogens, they have different receptor mechanisms of action and have not been directly compared. OBJECTIVE: This study compared subjective, behavioral, and physiological effects of psilocybin and dextromethorphan under conditions that minimized expectancy effects. METHODS: Single, acute oral doses of psilocybin (10, 20, 30 mg/70 kg), DXM (400 mg/70 kg), and placebo were administered under double-blind conditions to 20 healthy participants with histories of hallucinogen use...
November 7, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/29109907/a-temporal-white-noise-analysis-for-extracting-the-impulse-response-function-of-the-human-electroretinogram
#2
Andrew J Zele, Beatrix Feigl, Pradeep K Kambhampati, Avinash Aher, Declan McKeefry, Neil Parry, John Maguire, Ian Murray, Jan Kremers
Purpose: We introduce a method for determining the impulse response function (IRF) of the ERG derived from responses to temporal white noise (TWN) stimuli. Methods: This white noise ERG (wnERG) was recorded in participants with normal trichromatic vision to full-field (Ganzfeld) and 39.3° diameter focal stimuli at mesopic and photopic mean luminances and at different TWN contrasts. The IRF was obtained by cross-correlating the TWN stimulus with the wnERG. Results: We show that wnERG recordings are highly repeatable, with good signal-to-noise ratio, and do not lead to blink artifacts...
November 2017: Translational Vision Science & Technology
https://www.readbyqxmd.com/read/29104560/in-a-heartbeat-light-and-cardiovascular-physiology
#3
REVIEW
Sarah L Chellappa, Ruta Lasauskaite, Christian Cajochen
Light impinging on the retina fulfils a dual function: it serves for vision and it is required for proper entrainment of the endogenous circadian timing system to the 24-h day, thus influencing behaviors that promote health and optimal quality of life but are independent of image formation. The circadian pacemaker located in the suprachiasmatic nuclei modulates the cardiovascular system with an intrinsic ability to anticipate morning solar time and with a circadian nature of adverse cardiovascular events. Here, we infer that light exposure might affect cardiovascular function and provide evidence from existing research...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/29104256/fall-prediction-and-prevention-systems-recent-trends-challenges-and-future-research-directions
#4
REVIEW
Ramesh Rajagopalan, Irene Litvan, Tzyy-Ping Jung
Fall prediction is a multifaceted problem that involves complex interactions between physiological, behavioral, and environmental factors. Existing fall detection and prediction systems mainly focus on physiological factors such as gait, vision, and cognition, and do not address the multifactorial nature of falls. In addition, these systems lack efficient user interfaces and feedback for preventing future falls. Recent advances in internet of things (IoT) and mobile technologies offer ample opportunities for integrating contextual information about patient behavior and environment along with physiological health data for predicting falls...
November 1, 2017: Sensors
https://www.readbyqxmd.com/read/29091835/biomarker-and-histopathological-responses-of-lates-calcarifer-on-exposure-to-sub-lethal-concentrations-of-chlorpyrifos
#5
S R Marigoudar, D Mohan, A Nagarjuna, P Karthikeyan
Bioassay tests on fingerlings (3.0 ± 0.5cm) of euryhyaline fish Lates calcarifer were conducted using customized continuous flow through system and derived 96h acute toxicity value for chlorpyrifos (CPF). Based on the measured concentration of CPF mean median lethal concentration (LC50) of 1.07µg/l with lower and upper 95% confidence limits (0.95 and 1.19µg/l). No observed Effect Concentration (NOEC), Lowest Observed Effect Concentration (LOEC) and chronic values were found to be 0.4, 0.09 and 0.07µg/l respectively...
October 29, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29090052/review-of-static-approaches-to-surgical-correction-of-presbyopia
#6
REVIEW
Mohammad Ali Zare Mehrjerdi, Masomeh Mohebbi, Mehdi Zandian
Presbyopia is the primary cause of reduction in the quality of life of people in their 40s, due to dependence on spectacles. Therefore, presbyopia correction has become an evolving and rapidly progressive field in refractive surgery. There are two primary options for presbyopia correction: the dynamic approach uses the residual accommodative capacity of the eye, and the static approach attempts to enhance the depth of focus of the optical system. The dynamic approach attempts to reverse suspected pathophysiologic changes...
October 2017: Journal of Ophthalmic & Vision Research
https://www.readbyqxmd.com/read/29075008/age-related-changes-in-the-spatiotemporal-responses-to-electrical-stimulation-in-the-visual-cortex-of-rats-with-progressive-vision-loss
#7
Soshi Miyamoto, Naofumi Suematsu, Yuichi Umehira, Yuki Hayashida, Tetsuya Yagi
The Royal College of Surgeons (RCS) rat gradually loses vision due to retinal degeneration. Previous physiological studies have depicted the progressive loss of optical responses in the visual pathway, including the primary visual cortex (V1), over the course of retinal degeneration in the RCS rat. However, little is known about how the excitability of the V1 circuit changes during over the course of the gradual loss of visual signal input from the retina. We elucidated the properties of responses to electrical stimulations directly applied to V1 at different stages of vision input loss in the RCS rat in reference to those of the Long-Evans (LE) rat, using in vivo voltage-sensitive dye imaging...
October 26, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29067673/a-few-remarks-on-spatial-interference-in-visual-stimuli
#8
Bernt Christian Skottun
Many vision experiments, e.g., tests of masking and visual crowding, involve the effect of adding a second stimulus to an initial one. The effects of such additions are generally considered in terms of physiological mechanisms and the possibility of interference in the stimuli is generally not considered. In the present study, interference between two stimuli was assessed by comparing the sum of amplitudes in the combined stimulus to the sums of the amplitudes in the two stimuli determined separately. With this approach, evidence for interference was found...
October 24, 2017: Behavior Research Methods
https://www.readbyqxmd.com/read/29063836/patient-specific-mutations-impair-bestrophin1-s-essential-role-in-mediating-ca-2-dependent-cl-currents-in-human-rpe
#9
Yao Li, Yu Zhang, Yu Xu, Alec Kittredge, Nancy Ward, Shoudeng Chen, Stephen H Tsang, Tingting Yang
Mutations in the human BEST1 gene lead to retinal degenerative diseases displaying progressive vision loss and even blindness. BESTROPHIN1, encoded by BEST1, is predominantly expressed in retinal pigment epithelium (RPE), but its physiological role has been a mystery for the last two decades. Using a patient-specific iPSC-based disease model and interdisciplinary approaches, we comprehensively analyzed two distinct BEST1 patient mutations, and discovered mechanistic correlations between patient clinical phenotypes, electrophysiology in their RPEs, and the structure and function of BESTROPHIN1 mutant channels...
October 24, 2017: ELife
https://www.readbyqxmd.com/read/29060185/can-accelerometry-data-improve-estimates-of-heart-rate-variability-from-wrist-pulse-ppg-sensors
#10
Maciej Kos, Xuan Li, Iman Khaghani-Far, Christine M Gordon, Misha Pavel, Holly B Jimison
A key prerequisite for precision medicine is the ability to assess metrics of human behavior objectively, unobtrusively and continuously. This capability serves as a framework for the optimization of tailored, just-in-time precision health interventions. Mobile unobtrusive physiological sensors, an important prerequisite for realizing this vision, show promise in implementing this quality of physiological data collection. However, first we must trust the collected data. In this paper, we present a novel approach to improving heart rate estimates from wrist pulse photoplethysmography (PPG) sensors...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29052606/the-evolution-of-eyes-major-steps-the-keeler-lecture-2017-centenary-of-keeler-ltd
#11
I R Schwab
Ocular evolution is an immense topic, and I do not expect to cover all the details of this process in this manuscript. I will present some concepts about some of the major steps in the evolutionary process to stimulate your thinking about this interesting and complex topic. In the prebiotic soup, vision was not inevitable. Eyes were not preordained. Nor were their shapes, sizes, or current physiology. Sight is an evolutionary gift but it was not ineluctable. The existence of eyes is so basic to our profession that we often do not consider how and why vision appeared or evolved on earth at all...
October 20, 2017: Eye
https://www.readbyqxmd.com/read/29049074/physiology-and-role-of-intraocular-pressure-in-contemporary-anesthesia
#12
Dermot J Kelly, Sinéad M Farrell
More than 26 million Americans suffer with cataracts, and with 3.6 million cataract extractions performed annually in the United States, it is the most common surgical procedure. The integrity of the delicate structures of the eye that mediate vision is dependent on the intraocular pressure (IOP). Yet, IOP acts to compress the vessels within the globe-akin to a Starling resistor-and is a key component that determines the ocular perfusion pressure, defined as the difference between arterial pressure and IOP...
October 17, 2017: Anesthesia and Analgesia
https://www.readbyqxmd.com/read/29045837/the-circadian-clock-gene-bmal1-controls-thyroid-hormone-mediated-spectral-identity-and-cone-photoreceptor-function
#13
Onkar B Sawant, Amanda M Horton, Olivia F Zucaro, Ricky Chan, Vera L Bonilha, Ivy S Samuels, Sujata Rao
Circadian clocks regulate various aspects of photoreceptor physiology, but their contribution to photoreceptor development and function is unclear. Cone photoreceptors are critical for color vision. Here, we define the molecular function of circadian activity within cone photoreceptors and reveal a role for the clock genes Bmal1 and Per2 in regulating cone spectral identity. ChIP analysis revealed that BMAL1 binds to the promoter region of the thyroid hormone (TH)-activating enzyme type 2 iodothyronine deiodinase (Dio2) and thus regulates the expression of Dio2...
October 17, 2017: Cell Reports
https://www.readbyqxmd.com/read/29043113/simultaneous-tracking-of-cardiorespiratory-signals-for-multiple-persons-using-a-machine-vision-system-with-noise-artifact-removal
#14
Ali Al-Naji, Javaan Chahl
Most existing non-contact monitoring systems are limited to detecting physiological signs from a single subject at a time. Still, another challenge facing these systems is that they are prone to noise artifacts resulting from motion of subjects, facial expressions, talking, skin tone, and illumination variations. This paper proposes an efficient non-contact system based on a digital camera to track the cardiorespiratory signal from a number of subjects (up to six persons) at the same time with a new method for noise artifact removal...
2017: IEEE Journal of Translational Engineering in Health and Medicine
https://www.readbyqxmd.com/read/29038079/optical-coherence-tomography-in-the-management-of-skull-base-fibrous-dysplasia-with-optic-nerve-involvement
#15
Joshua Loewenstern, Christopher M Hernandez, Carolyn Chadwick, Amish Doshi, Rudrani Banik, Christopher A Sarkiss, Joshua Bederson, Raj K Shrivastava
BACKGROUND: Fibrous dysplasia (FD) of the skull base can present with optic nerve compression. As most patients initially do not experience vision loss, controversy exists whether to proceed with prophylactic surgical decompression or elect for conservative observation. Optical coherence tomography (OCT), a physiologic imaging modality widely used to assess the condition of the retinal nerve fiber layer (RNFL), has been useful in monitoring compressive tumors on the optic nerve. The present study evaluated the potential use of OCT in the management of FD patients with optic nerve involvement...
October 13, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/29018076/protocol-for-a-prospective-interventional-trial-to-develop-a-diagnostic-index-test-for-stroke-as-a-cause-of-vertigo-dizziness-and-imbalance-in-the-emergency-room-emvert-study
#16
Ken Möhwald, Stanislavs Bardins, Hans-Helge Müller, Klaus Jahn, Andreas Zwergal
INTRODUCTION: Identifying stroke as a cause of acute vertigo, dizziness and imbalance in the emergency room is still a clinical challenge. Many patients are admitted to stroke units, but only a minority will have strokes. This imposes a heavy financial burden on the healthcare system. The aim of this study is to develop a diagnostic index test to identify patients with a high risk of having a stroke as the cause of acute vertigo and imbalance. METHODS AND ANALYSIS: Patients with acute onset of vertigo, dizziness, postural imbalance or double vision within the last 24 hours lasting for at least 10 min are eligible to be included in the study...
October 10, 2017: BMJ Open
https://www.readbyqxmd.com/read/28992301/sensory-biology-of-starfish-with-emphasis-on-recent-discoveries-in-their-visual-ecology
#17
Anders Garm
Asteroidea, starfish, constitutes a major part of the macrobenthos in most marine environments. Being members of the echinoderms, they have a nervous system with no well-defined central nervous system. Accordingly, starfish are assumed to pick up rather limited information from the surroundings, and it is also often assumed that most of their behaviors are guided by olfaction. Here, the sensory biology of starfish is reviewed in order to evaluate these assumptions. There is a vast amount of behavioral data dealing with mechanoreception, chemoreception, and combinations of the two (chemosensory-mediated rheotaxis), but the receptors have not yet been identified and almost nothing is known about the physiology behind these senses...
August 28, 2017: Integrative and Comparative Biology
https://www.readbyqxmd.com/read/28991350/neuroanatomical-structures-in-human-extraocular-muscles-and-their-potential-implication-in-the-development-of-oculomotor-disorders
#18
Ala Paduca, Jan Richard Bruenech
The potential role of sensory feedback from human extraocular muscles has been subjected to considerable speculation in the ophthalmic literature. Extraocular muscles pull against a fairly even load and do not initiate a stretch reflex, even when the eyes are directed toward the boundaries of their respective field of action. These unique working conditions and physiological properties have led to the notion that the sensory signal arising from receptors in extraocular muscles differs from the conventional proprioceptive signal arising from their somatic counterparts...
October 9, 2017: Journal of Pediatric Ophthalmology and Strabismus
https://www.readbyqxmd.com/read/28987037/hypnosis-and-osteopathic-manipulative-treatment-for-visual-disorders-during-pregnancy-a-case-report
#19
Giancarlo Russo, Alessandro Remonato, Roberto Remonato, Emiliano Zanier
Context • Pregnancy causes physiological alterations to the visual system, particularly in relation to retinal vascularization, with a consequent increase of intraocular pressure, and to the lacrimal fluid, with a consequent ocular dryness, which both can lead to a reduction in visual acuity. Numerous case reports refer to the employment of hypnotic treatment in cases of myopia, but the literature does not report any case of decreased visual acuity postpartum that was treated with hypnosis. Objective • For women with visual disorders that had appeared during pregnancy or were preexisting, the study intended to evaluate the benefits of treatment of the diaphragm by hypnotherapy and osteopathy to modify intracorporeal pressure and restore the women's visual function...
July 2017: Advances in Mind-body Medicine
https://www.readbyqxmd.com/read/28969095/mechanisms-of-phosphenes-in-irradiated-patients
#20
REVIEW
Thibaud Mathis, Stephane Vignot, Cecila Leal, Jean-Pierre Caujolle, Celia Maschi, Martine Mauget-Faÿsse, Laurent Kodjikian, Stéphanie Baillif, Joel Herault, Juliette Thariat
Anomalous visual perceptions have been reported in various diseases of the retina and visual pathways or can be experienced under specific conditions in healthy individuals. Phosphenes are perceptions of light in the absence of ambient light, occurring independently of the physiological and classical photonic stimulation of the retina. They are a frequent symptom in patients irradiated in the region of the central nervous system (CNS), head and neck and the eyes. Phosphenes have historically been attributed to complex physical phenomena such as Cherenkov radiation...
September 8, 2017: Oncotarget
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