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1.
Am J Ophthalmol Case Rep ; 26: 101468, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35274065

ABSTRACT

Purpose: To determine the characteristics and clinical course of an eye with a peripapillary staphyloma and an optic disc pit associated with a retinal detachment (RD) and retinoschisis. Observations: A 44-year-old woman had a peripapillary staphyloma with a shallow RD and retinoschisis in her right eye. The optic disc was located in the peripapillary staphyloma with steep walls, and an optic disc pit was located on the temporal area of the optic disc cup. Optical coherence tomography (OCT) revealed a separation of the lamina cribrosa, herniated retinal tissue, and a subarachnoid space corresponding to the optic disc pit. Pars plana vitrectomy with laser photocoagulation around the temporal margin of the peripapillary staphyloma was performed to treat the RD, and the treatment was successful. Conclusion and importance: Clinicians should be aware that eyes with a RD and retinoschisis associated with a deep peripapillary staphyloma and an optic disc pit exist. The RD and retinoschisis can be successfully treated by vitrectomy.

2.
Front Physiol ; 12: 738973, 2021.
Article in English | MEDLINE | ID: mdl-34566701

ABSTRACT

Wearable technologies for measuring digital and chemical physiology are pervading the consumer market and hold potential to reliably classify states of relevance to human performance including stress, sleep deprivation, and physical exertion. The ability to efficiently and accurately classify physiological states based on wearable devices is improving. However, the inherent variability of human behavior within and across individuals makes it challenging to predict how identified states influence human performance outcomes of relevance to military operations and other high-stakes domains. We describe a computational modeling approach to address this challenge, seeking to translate user states obtained from a variety of sources including wearable devices into relevant and actionable insights across the cognitive and physical domains. Three status predictors were considered: stress level, sleep status, and extent of physical exertion; these independent variables were used to predict three human performance outcomes: reaction time, executive function, and perceptuo-motor control. The approach provides a complete, conditional probabilistic model of the performance variables given the status predictors. Construction of the model leverages diverse raw data sources to estimate marginal probability density functions for each of six independent and dependent variables of interest using parametric modeling and maximum likelihood estimation. The joint distributions among variables were optimized using an adaptive LASSO approach based on the strength and directionality of conditional relationships (effect sizes) derived from meta-analyses of extant research. The model optimization process converged on solutions that maintain the integrity of the original marginal distributions and the directionality and robustness of conditional relationships. The modeling framework described provides a flexible and extensible solution for human performance prediction, affording efficient expansion with additional independent and dependent variables of interest, ingestion of new raw data, and extension to two- and three-way interactions among independent variables. Continuing work includes model expansion to multiple independent and dependent variables, real-time model stimulation by wearable devices, individualized and small-group prediction, and laboratory and field validation.

3.
Psychiatry Res ; 286: 112862, 2020 Feb 10.
Article in English | MEDLINE | ID: mdl-32113035

ABSTRACT

Auditory hallucinations (AH) are one of the core symptoms of schizophrenia (SZ) and constitute a significant source of suffering and disability. One third of SZ patients experience pharmacology-resistant AH, so an alternative/complementary treatment strategy is needed to alleviate this debilitating condition. In this study, real-time functional Magnetic Resonance Imaging neurofeedback (rt-fMRI NFB), a non-invasive technique, was used to teach 10 SZ patients with pharmacology-resistant AH to modulate their brain activity in the superior temporal gyrus (STG), a key area in the neurophysiology of AH. A functional task was designed in order to provide patients with a specific strategy to help them modify their brain activity in the desired direction. Specifically, they received neurofeedback from their own STG and were trained to upregulate it while listening to their own voice recording and downregulate it while ignoring a stranger's voice recording. This guided performance neurofeedback training resulted in a) a significant reduction in STG activation while ignoring a stranger's voice, and b) reductions in AH scores after the neurofeedback session. A single, 21-minute session of rt-fMRI NFB was enough to produce these effects, suggesting that this approach may be an efficient and clinically viable alternative for the treatment of pharmacology-resistant AH.

4.
Psychiatry Res ; 284: 112770, 2020 02.
Article in English | MEDLINE | ID: mdl-32004893

ABSTRACT

Auditory hallucinations (AHs) are one of the most distressing symptoms of schizophrenia (SZ) and are often resistant to medication. Imaging studies of individuals with SZ show hyperactivation of the default mode network (DMN) and the superior temporal gyrus (STG). Studies in SZ show DMN hyperconnectivity and reduced anticorrelation between DMN and the central executive network (CEN). DMN hyperconnectivity has been associated with positive symptoms such as AHs while reduced DMN anticorrelations with cognitive impairment. Using real-time fMRI neurofeedback (rt-fMRI-NFB) we trained SZ patients to modulate DMN and CEN networks. Meditation is effective in reducing AHs in SZ and to modulate brain network integration and increase DMN anticorrelations. Consequently, patients were provided with meditation strategies to enhance their abilities to modulate DMN/CEN. Results show a reduction of DMN hyperconnectivity and increase in DMNCEN anticorrelation. Furthermore, the change in individual DMN connectivity significantly correlated with reductions in AHs. This is the first time that meditation enhanced through rt-fMRI-NFB is used to reduce AHs in SZ. Moreover, it provides the first empirical evidence for a direct causal relation between meditation enhanced rt-fMRI-NFB modulation of DMNCEN activity and post-intervention modulation of resting state networks ensuing in reductions in frequency and severity of AHs.


Subject(s)
Brain/diagnostic imaging , Hallucinations/diagnostic imaging , Magnetic Resonance Imaging/methods , Nerve Net/diagnostic imaging , Neurofeedback/methods , Schizophrenia/diagnostic imaging , Adult , Brain Mapping/methods , Female , Hallucinations/therapy , Humans , Male , Meditation/methods , Meditation/psychology , Middle Aged , Proof of Concept Study , Rest , Schizophrenia/therapy
5.
NPJ Sci Learn ; 4: 16, 2019.
Article in English | MEDLINE | ID: mdl-31583118

ABSTRACT

Although numerous survey studies have reported connections between sleep and cognitive function, there remains a lack of quantitative data using objective measures to directly assess the association between sleep and academic performance. In this study, wearable activity trackers were distributed to 100 students in an introductory college chemistry class (88 of whom completed the study), allowing for multiple sleep measures to be correlated with in-class performance on quizzes and midterm examinations. Overall, better quality, longer duration, and greater consistency of sleep correlated with better grades. However, there was no relation between sleep measures on the single night before a test and test performance; instead, sleep duration and quality for the month and the week before a test correlated with better grades. Sleep measures accounted for nearly 25% of the variance in academic performance. These findings provide quantitative, objective evidence that better quality, longer duration, and greater consistency of sleep are strongly associated with better academic performance in college. Gender differences are discussed.

6.
PLoS One ; 13(10): e0206250, 2018.
Article in English | MEDLINE | ID: mdl-30356311

ABSTRACT

Digital learning is becoming the most commonly used portal for workplace learning, but its effectiveness is not clearly understood. We studied 99 employees on-site in a large company as they watched an already used and required training video. Employees were randomly assigned to one of four conditions: (1) a baseline condition of watching the video as in current practice; (2) a spontaneous discussion condition in which participants discussed the video with colleagues immediately after the video without any guidelines; (3) a structured discussion condition in which participants discussed the video with colleagues immediately after the video with an instructor guiding discussion topics; and (4) a testing condition in which test questions were interpolated throughout the video. Memory for the content of the video was measured on a recognition memory test completed 20-35 hours after watching the video. Employees who were in the interpolated-testing or structured discussion conditions had significantly superior memory for the video content (26% and 25% better respectively) relative to typical video viewing; spontaneous discussion did not enhance memory for content. These findings demonstrate that interpolated testing and structured discussion enhance information retention in the workplace and point to how learning science may accelerate workplace learning more generally.


Subject(s)
Learning , Teaching , Workplace , Adult , Female , Humans , Male , Memory , Middle Aged , Video Recording
7.
PLoS One ; 11(11): e0165046, 2016.
Article in English | MEDLINE | ID: mdl-27829030

ABSTRACT

The aims of this randomized observational case control study were to quantify fixation behavior during standard automated perimetry (SAP) with different fixation targets and to evaluate the relationship between fixation behavior and threshold variability at each test point in healthy young participants experienced with perimetry. SAP was performed on the right eyes of 29 participants using the Octopus 900 perimeter, program 32, dynamic strategy. The fixation targets of Point, Cross, and Ring were used for SAP. Fixation behavior was recorded using a wearable eye-tracking glass. All participants underwent SAP twice with each fixation target in a random fashion. Fixation behavior was quantified by calculating the bivariate contour ellipse area (BCEA) and the frequency of deviation from the fixation target. The BCEAs (deg2) of Point, Cross, and Ring targets were 1.11, 1.46, and 2.02, respectively. In all cases, BCEA increased significantly with increasing fixation target size (p < 0.05). The logarithmic value of BCEA demonstrated the same tendency (p < 0.05). A positive correlation was identified between fixation behavior and threshold variability for the Point and Cross targets (ρ = 0.413-0.534, p < 0.05). Fixation behavior increased with increasing fixation target size. Moreover, a larger fixation behavior tended to be associated with a higher threshold variability. A small fixation target is recommended during the visual field test.


Subject(s)
Fixation, Ocular/physiology , Visual Acuity/physiology , Visual Field Tests/methods , Visual Fields/physiology , Adult , Case-Control Studies , Humans , Prospective Studies , Reproducibility of Results , Sensory Thresholds/physiology , Visual Field Tests/instrumentation , Visual Perception/physiology , Young Adult
8.
J Neurolinguistics ; 37: 58-67, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26516296

ABSTRACT

In a masked cross-modal priming experiment with ERP recordings, spoken Japanese words were primed with words written in one of the two syllabary scripts of Japanese. An early priming effect, peaking at around 200ms after onset of the spoken word target, was seen in left lateral electrode sites for Katakana primes, and later effects were seen for both Hiragana and Katakana primes on the N400 ERP component. The early effect is thought to reflect the efficiency with which words in Katakana script make contact with sublexical phonological representations involved in spoken language comprehension, due to the particular way this script is used by Japanese readers. This demonstrates fast-acting influences of visual primes on the processing of auditory target words, and suggests that briefly presented visual primes can influence sublexical processing of auditory target words. The later N400 priming effects, on the other hand, most likely reflect cross-modal influences on activity at the level of whole-word phonology and semantics.

9.
Cogn Affect Behav Neurosci ; 13(2): 390-404, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23378278

ABSTRACT

The bimodal interactive-activation model has been successfully applied to understanding the neurocognitive processes involved in reading words in alphabetic scripts, as reflected in the modulation of ERP components in masked repetition priming. In order to test the generalizability of this approach, in the present study we examined word recognition in a different writing system, the Japanese syllabary scripts hiragana and katakana. Native Japanese participants were presented with repeated or unrelated pairs of Japanese words in which the prime and target words were both in the same script (within-script priming, Exp. 1) or were in the opposite script (cross-script priming, Exp. 2). As in previous studies with alphabetic scripts, in both experiments the N250 (sublexical processing) and N400 (lexical-semantic processing) components were modulated by priming, although the time course was somewhat delayed. The earlier N/P150 effect (visual feature processing) was present only in "Experiment 1: Within-script priming", in which the prime and target words shared visual features. Overall, the results provide support for the hypothesis that visual word recognition involves a generalizable set of neurocognitive processes that operate in similar manners across different writing systems and languages, as well as pointing to the viability of the bimodal interactive-activation framework for modeling such processes.


Subject(s)
Evoked Potentials/physiology , Recognition, Psychology/physiology , Semantics , Vocabulary , Adult , Brain Mapping , Decision Making , Electroencephalography , Female , Humans , Male , Photic Stimulation , Reaction Time/physiology , Time Factors , Young Adult
10.
PLoS One ; 5(5): e10793, 2010 May 25.
Article in English | MEDLINE | ID: mdl-20520833

ABSTRACT

What kind of mental objects are letters? Research on letter perception has mainly focussed on the visual properties of letters, showing that orthographic representations are abstract and size/shape invariant. But given that letters are, by definition, mappings between symbols and sounds, what is the role of sound in orthographic representation? We present two experiments suggesting that letters are fundamentally sound-based representations. To examine the role of sound in orthographic representation, we took advantage of the multiple scripts of Japanese. We show two types of evidence that if a Japanese word is presented in a script it never appears in, this presentation immediately activates the ("actual") visual word form of that lexical item. First, equal amounts of masked repetition priming are observed for full repetition and when the prime appears in an atypical script. Second, visual word form frequency affects neuromagnetic measures already at 100-130 ms whether the word is presented in its conventional script or in a script it never otherwise appears in. This suggests that Japanese orthographic codes are not only shape-invariant, but also script invariant. The finding that two characters belonging to different writing systems can activate the same form representation suggests that sound identity is what determines orthographic identity: as long as two symbols express the same sound, our minds represent them as part of the same character/letter.


Subject(s)
Magnetoencephalography , Perceptual Masking/physiology , Phonetics , Adult , Humans , Middle Aged , Photic Stimulation , Young Adult
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