Read by QxMD icon Read

pupil dilation

Michal T Kucewicz, Jaromir Dolezal, Vaclav Kremen, Brent M Berry, Laura R Miller, Abigail L Magee, Vratislav Fabian, Gregory A Worrell
Pupil responses are known to indicate brain processes involved in perception, attention and decision-making. They can provide an accessible biomarker of human memory performance and cognitive states in general. Here we investigated changes in the pupil size during encoding and recall of word lists. Consistent patterns in the pupil response were found across and within distinct phases of the free recall task. The pupil was most constricted in the initial fixation phase and was gradually more dilated through the subsequent encoding, distractor and recall phases of the task, as the word items were maintained in memory...
March 21, 2018: Scientific Reports
Daisuke Shimaoka, Kenneth D Harris, Matteo Carandini
Changes in arousal modulate the activity of mouse sensory cortex, but studies in different mice and different sensory areas disagree on whether this modulation enhances or suppresses activity. We measured this modulation simultaneously in multiple cortical areas by imaging mice expressing voltage-sensitive fluorescent proteins (VSFP). VSFP imaging estimates local membrane potential across large portions of cortex. We used temporal filters to predict local potential from running speed or from pupil dilation, two measures of arousal...
March 20, 2018: Cell Reports
Manuel Oliva, Andrey Anikin
The processing of emotional signals usually causes an increase in pupil size, and this effect has been largely attributed to autonomic arousal prompted by the stimuli. Additionally, changes in pupil size were associated with decision making during non-emotional perceptual tasks. Therefore, in this study we investigated the relationship between pupil size fluctuations and the process of emotion recognition. Participants heard human nonverbal vocalizations (e.g., laughing, crying) and indicated the emotional state of the speakers as soon as they had identified it...
March 20, 2018: Scientific Reports
Mihyun Choi, Marjorie Z Lazo, Minji Kang, Jeehye Lee, Choun-Ki Joo
BACKGROUND: The present study aimed to evaluate the degree of anterior capsule contraction (capsulorhexis contraction) with three different single-piece, hydrophilic acrylic intraocular lenses (IOLs). METHODS: Patients were prospectively randomized to be implanted with one of three types of IOLs during cataract surgery: the Ophtec Precizon (IOL A), the Lucid Korea Microflex (IOL B), and the Carl Zeiss Asphina (IOL C). One week, 2 weeks, and 6 months after surgery, the area of the anterior capsule opening was measured using digital retro-illumination images after dilation of the pupil...
March 20, 2018: BMC Ophthalmology
Michelle Hershman, Raymond Carmody, Unni K Udayasankar
History A 19-year-old woman with no pertinent medical history was brought to the emergency department after being found unconscious on her bathroom floor by her roommate. In the preceding weeks, she had reported intractable nausea and vomiting, for which she had been taking ondansetron. No other medications had been prescribed. The day prior to presentation, she had contacted her mother and described increasing confusion. Glasgow coma scale score on arrival in the emergency department was 4. Intravenous naloxone was administered, without immediate response...
April 2018: Radiology
Roger Johansson, Philip Pärnamets, Amanda Bjernestedt, Mikael Johansson
Mnemonic interference refers to the inability to retrieve a goal-relevant memory due to interference from goal-irrelevant memories. Understanding the causes of such interference and how it is overcome has been a central goal in the science of memory for more than a century. Here, we shed new light on this fundamental issue by tracking participants' pupil response when they encode and retrieve memories in the face of competing goal-irrelevant memories. We show that pupil dilation systematically increased in accordance with interference from competing memory traces when participants retrieved previously learned information...
March 19, 2018: Scientific Reports
Antonio Jose Reyes, Kanterpersad Ramcharan, Samuel Aboh, Stanley Lawrence Giddings
No abstract text is available yet for this article.
March 15, 2018: BMJ Case Reports
Min-Qing Wang, Xu Zhao, Xiao-Fei Wang, Chao Han, De-Guang Xing, Cheng-Wei Wang
BACKGROUND: The purpose of this study was to assess the outcomes in aggressively treated patients with aneurysmal intracerebral hematoma (ICH) and signs of brain herniation, and to investigate possible predictive factors. METHODS: This retrospective study included 43 patients with aneurysmal ICH who presented with brain herniation at emergency department (ED) admission and received aggressive surgical treatment between 2008 and 2016. Emergency surgical clipping, removal of hematoma, and external decompression were combined as an aggressive surgical treatment...
March 12, 2018: World Neurosurgery
Madan Upadhyay, Ranju Kharel Sitaula, Bharat Shrestha, Bhaiya Khanal, Bishnu Psd Upadhyay, Jeevan B Sherchand, Prakash Ghimire
PURPOSE: This review aims to provide a detailed update in Seasonal hypercute panuveitis (SHAPU) which is a blinding disease of unknown etiology reported only from Nepal, occurring every odd year since 1975 predominantly in children. METHODS: Data sources were literature reviewed using PubMed, Medline, and ISI Databases (since 1975 to late 2017). Search items included SHAPU, seasonal endophthalmitis, hypopyon uveitis, caterpillar induced uveitis alone or in combination with white moth, panuveitis, and review...
March 15, 2018: Ocular Immunology and Inflammation
B E Malyugin, N S Anisimova
In certain cases intraoperative pupil dilation during cataract surgery may be necessary to improve the visualization of intraocular structures and assure the atraumatic nature of surgical manipulations. The article reviews a wide range of pupil expanders, their historical aspects and possibilities of their application in modern cataract surgery.
2018: Vestnik Oftalmologii
Rebecca Jürgens, Julia Fischer, Annekathrin Schacht
Emotional expressions provide strong signals in social interactions and can function as emotion inducers in a perceiver. Although speech provides one of the most important channels for human communication, its physiological correlates, such as activations of the autonomous nervous system (ANS) while listening to spoken utterances, have received far less attention than in other domains of emotion processing. Our study aimed at filling this gap by investigating autonomic activation in response to spoken utterances that were embedded into larger semantic contexts...
2018: Frontiers in Psychology
Royston K Y Tan, Xiaofei Wang, Shamira A Perera, Michaël J A Girard
PURPOSE: (1) To use finite element (FE) modelling to estimate local iris stresses (i.e. internal forces) as a result of mechanical pupil expansion; and to (2) compare such stresses as generated from several commercially available expanders (Iris hooks, APX dilator and Malyugin ring) to determine which design and deployment method are most likely to cause iris damage. METHODS: We used a biofidelic 3-part iris FE model that consisted of the stroma, sphincter and dilator muscles...
2018: PloS One
Charlotte A Hall, Robert P Chilcott
The pupillary light reflex (PLR) describes the constriction and subsequent dilation of the pupil in response to light as a result of the antagonistic actions of the iris sphincter and dilator muscles. Since these muscles are innervated by the parasympathetic and sympathetic nervous systems, respectively, different parameters of the PLR can be used as indicators for either sympathetic or parasympathetic modulation. Thus, the PLR provides an important metric of autonomic nervous system function that has been exploited for a wide range of clinical applications...
March 13, 2018: Diagnostics
Hyun-Seok Park, Jae-Hyung Choi
OBJECTIVE: The beneficial effect of hypothermia after hemicraniectomy in malignant middle cerebral artery (MCA) infarction has been controversial. We aim to investigate the safety and clinical efficacy of hypothermia after hemicraniectomy in malignant MCA infarction. METHODS: From October 2012 to February 2016, 20 patients underwent hypothermia (Blanketrol III, Cincinnati Sub-Zero, Cincinnati, OH, USA) at 34°C after hemicraniectomy in malignant MCA infarction (hypothermia group)...
March 2018: Journal of Korean Neurosurgical Society
Andreas Brocher, Raphael Harbecke, Tim Graf, Daniel Memmert, Stefanie Hüttermann
We tested the link between pupil size and the task effort involved in covert shifts of visual attention. The goal of this study was to establish pupil size as a marker of attentional shifting in the absence of luminance manipulations. In three experiments, participants evaluated two stimuli that were presented peripherally, appearing equidistant from and on opposite sides of eye fixation. The angle between eye fixation and the peripherally presented target stimuli varied from 12.5° to 42.5°. The evaluation of more distant stimuli led to poorer performance than did the evaluation of more proximal stimuli throughout our study, confirming that the former required more effort than the latter...
March 7, 2018: Behavior Research Methods
Marco Turi, David Charles Burr, Paola Binda
The pupil is primarily regulated by prevailing light levels but is also modulated by perceptual and attentional factors. We measured pupil-size in typical adult humans viewing a bistable-rotating cylinder, constructed so the luminance of the front surface changes with perceived direction of rotation. In some participants, pupil diameter oscillated in phase with the ambiguous perception, more dilated when the black surface was in front. Importantly, the magnitude of oscillation predicts autistic traits of participants, assessed by the Autism-Spectrum Quotient AQ...
March 6, 2018: ELife
Christine Fawcett, Melda Arslan, Terje Falck-Ytter, Herbert Roeyers, Gustaf Gredebäck
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
March 2, 2018: Scientific Reports
Paris Tranos, Evangelos Lokovitis, Stelios Masselos, Nikolaos Kozeis, Magda Triantafylla, Nikolaos Markomichelakis
OBJECTIVES: To describe the demographic characteristics, clinical features, and potential prognostic factors of bilateral acute iris transillumination (BAIT) following oral antibiotic uptake. METHODS: A retrospective study of 16 consecutive patients who developed BAIT following treatment with systemic antibiotics. Detailed past medical and ocular history was obtained, presenting signs and symptoms were documented and demographic characteristics were analyzed. All patients underwent a complete ocular examination and laboratory investigation...
March 2, 2018: Eye
Nash Unsworth, Matthew K Robison, Ashley L Miller
The current study examined pupillary correlates of fluctuations and lapses of sustained attention. Participants performed a sustained attention task with either a varied ISI or a fixed ISI (fixed at 2 or 8 sec) while pupil responses were continuously recorded. The results indicated that performance was worse when the ISI was varied or fixed at 8 sec compared with when the ISI was fixed at 2 sec, suggesting that varied or long ISI conditions require greater intrinsic alertness compared with constant short ISIs...
February 28, 2018: Journal of Cognitive Neuroscience
Luca Orlandi, Benjamin Brooks
This paper investigates the effects of shiphandling manoeuvres on mental workload and physiological reactions in ten marine pilots. Each pilot performed four berthings in a ship simulator. Those berthings were differentiated by two factors, level of difficulty and familiarity with the port. Each berthing could also be divided into five phases, three during the execution and two resting periods, one before and one after the execution (dedicated to baseline physiological data collection). Mental workload was measured through two self assessment scales: the NASA TLX and a Likert scale...
May 2018: Applied Ergonomics
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"