Primate Antisaccades. I. Behavioral Characteristics

1998 ◽  
Vol 80 (4) ◽  
pp. 1775-1786 ◽  
Author(s):  
Nelly Amador ◽  
Madeleine Schlag-Rey ◽  
John Schlag
Keyword(s):  
Human Performance ◽  
Error Rates ◽  
Behavioral Characteristics ◽  
Peripheral Stimulus ◽  
Primate Model ◽  
The Past ◽  
Frontal Lobe Lesions ◽  
Long Latency ◽  
Saccade Task ◽  
Central Fixation

Amador, Nelly, Madeleine Schlag-Rey, and John Schlag. Primate antisaccades. I. Behavioral characteristics. J. Neurophysiol. 80: 1775–1786, 1998. The antisaccade task requires a subject to make a saccade to an unmarked location opposite to a flashed stimulus. This task was originally designed to study saccades made to a goal specified by instructions. Interest for this paradigm surged after the discovery that frontal lobe lesions specifically and severely affect human performance of antisaccades while prosaccades (i.e., saccades directed to the visual stimulus) are facilitated. Training monkeys to perform antisaccades was rarely attempted in the past, and this study is the first one that describes in detail the properties of such antisaccades compared with randomly intermingled prosaccades of varying amplitude in all directions. Such randomization was found essential to force the monkeys to use the instruction cue (pro- or anti-) and the location cue (peripheral stimulus) provided within a trial rather than to direct their saccades to the location of past rewards. Each trial began with the onset of a central fixation target that conveyed by its shape the instruction to make a pro- or an antisaccade to a subsequent peripheral stimulus. In one version of the task, the monkey was allowed to make an immediate saccade to the goal; in a second version, the saccade had to wait for a go signal. Analyses of the accuracy, velocity, and latency of antisaccades compared with prosaccades were performed on a sample of 7,430 pro-/antisaccades in the “immediate saccade” task (delayed saccades suffering from known distortions). Error rates fluctuated ∼25%. Results were the same for the two monkeys with respect to accuracy and velocity, but they differed in terms of reaction time. Both monkeys generated antisaccades to stimuli in all directions, at various eccentricities, but antisaccades were significantly less accurate and slower than prosaccades elicited by the same stimuli. Interestingly, saccades to the stimulus could be followed by appropriate antisaccades with no intersaccadic interval. Such instances are here referred to as “turnaround saccades.” Because they occurred sometimes with a long latency, turnaround saccades did not simply reflect the cancellation of an early foveation reflex. Consistent with human data, latencies of one monkey were longer for antisaccades than for prosaccades, but the reverse was true for the other monkey who was trained differently. In summary, this study demonstrates the feasibility of providing a subhuman primate model of antisaccade performance, but at the same time it suggests some irreducible differences between human and monkey performance.

scholarly journals An infrared spectral biomarker accurately predicts neurodegenerative disease class in the absence of overt symptoms

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lila Lovergne ◽  
Dhruba Ghosh ◽  
Renaud Schuck ◽  
Aris A. Polyzos ◽  
Andrew D. Chen ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Neurodegenerative Disease ◽  
High Probability ◽  
Behavioral Characteristics ◽  
Brain Pathology ◽  
Disease Class ◽  
The Past ◽  
Infrared Spectral ◽  
New Biomarkers ◽  
Physiological Indicator

AbstractAlthough some neurodegenerative diseases can be identified by behavioral characteristics relatively late in disease progression, we currently lack methods to predict who has developed disease before the onset of symptoms, when onset will occur, or the outcome of therapeutics. New biomarkers are needed. Here we describe spectral phenotyping, a new kind of biomarker that makes disease predictions based on chemical rather than biological endpoints in cells. Spectral phenotyping uses Fourier Transform Infrared (FTIR) spectromicroscopy to produce an absorbance signature as a rapid physiological indicator of disease state. FTIR spectromicroscopy has over the past been used in differential diagnoses of manifest disease. Here, we report that the unique FTIR chemical signature accurately predicts disease class in mouse with high probability in the absence of brain pathology. In human cells, the FTIR biomarker accurately predicts neurodegenerative disease class using fibroblasts as surrogate cells.

Exercise Physiology From 1980 to 2020: Application of the Natural Sciences

2021 ◽  
pp. 1-10
Author(s):  
Jane A. Kent ◽  
Kate L. Hayes
Keyword(s):  
Human Performance ◽  
Exercise Physiology ◽  
Natural Sciences ◽  
The Past ◽  
Interdisciplinary Field ◽  
Advanced Technologies ◽  
Health And Disease ◽  
Fundamental Research ◽  
Research Questions ◽  
Underlying Mechanisms

The field of exercise physiology has enjoyed tremendous growth in the past 40 years. With its foundations in the natural sciences, it is an interdisciplinary field that is highly relevant to human performance and health. The focus of this review is on highlighting new approaches, knowledge, and opportunities that have emerged in exercise physiology over the last four decades. Key among these is the adoption of advanced technologies by exercise physiologists to address fundamental research questions, and the expansion of research topics to range from molecular to organismal, and population scales in order to clarify the underlying mechanisms and impact of physiological responses to exercise in health and disease. Collectively, these advances have ensured the position of the field as a partner in generating new knowledge across many scientific and health disciplines.

Algorithmic fairness in credit scoring

2021 ◽  
Vol 37 (3) ◽  
pp. 585-617
Author(s):  
Teresa Bono ◽  
Karen Croxson ◽  
Adam Giles
Keyword(s):  
Machine Learning ◽  
Credit Scoring ◽  
Large Data ◽  
Error Rates ◽  
The Past ◽  
Ensemble Machine Learning ◽  
Hidden Patterns ◽  
Credit Scoring Model ◽  
Distributional Impacts ◽  
Modelling Approach

Abstract The use of machine learning as an input into decision-making is on the rise, owing to its ability to uncover hidden patterns in large data and improve prediction accuracy. Questions have been raised, however, about the potential distributional impacts of these technologies, with one concern being that they may perpetuate or even amplify human biases from the past. Exploiting detailed credit file data for 800,000 UK borrowers, we simulate a switch from a traditional (logit) credit scoring model to ensemble machine-learning methods. We confirm that machine-learning models are more accurate overall. We also find that they do as well as the simpler traditional model on relevant fairness criteria, where these criteria pertain to overall accuracy and error rates for population subgroups defined along protected or sensitive lines (gender, race, health status, and deprivation). We do observe some differences in the way credit-scoring models perform for different subgroups, but these manifest under a traditional modelling approach and switching to machine learning neither exacerbates nor eliminates these issues. The paper discusses some of the mechanical and data factors that may contribute to statistical fairness issues in the context of credit scoring.

scholarly journals Psychosocial and Behavioral Characteristics among Subgroups of Nondaily College Student Smokers

2014 ◽  
Vol 7 ◽  
pp. TUI.S13440 ◽  
Author(s):  
Devan R. Romero ◽  
Kim Pulvers ◽  
Taneisha S. Scheuermann ◽  
Jasjit S. Ahluwalia
Keyword(s):  
Young Adults ◽  
College Student ◽  
Perceived Risk ◽  
Public University ◽  
Behavioral Characteristics ◽  
The Past ◽  
Quit Smoking ◽  
Quit Attempts ◽  
Different Characteristics ◽  
Nondaily Smoking

Nondaily smoking is becoming common in young adults and there appear to be different characteristics associated with past month smoking frequency among nondaily smokers. The present study examines behavioral and psychosocial correlates of smoking among subgroups of nondaily college student smokers ( N = 80; 18–25 years of age) attending a large, public university. Nondaily smokers were categorized based on the frequency of days smoked in the past month and were divided into two subgroups: 1–5 days and 6–29 days. A quarter of nondaily smokers considered themselves as a smoker and significantly more 6–29 nondaily smokers were identified as a smoker and smoked more cigarettes per day (CPD). Almost half (45%) of nondaily smokers have attempted to quit smoking completely and 71% of the 6–29 nondaily smokers reported significantly higher quit attempts. The 6–29 nondaily smokers had significantly higher perceived risk related to smoking. Self-efficacy to abstain from smoking was significantly higher for 1–5 nondaily smokers. These results suggest heterogeneity among subgroups of nondaily college student smokers exists in a number of behavioral and psychosocial factors. Prevention and cessation strategies may be improved by considering frequency of nondaily smoking and targeting subgroups differently.

VISUALIZATION OF SOVIET CHILDHOOD IN DRAWINGS BY EUGENIYA DVOSKINA

2020 ◽  
pp. 96-115
Author(s):  
Zhanna V. Umanskaya ◽  
Keyword(s):  
Everyday Life ◽  
Collective Memory ◽  
Behavioral Characteristics ◽  
Visual Sociology ◽  
Public And Private ◽  
The Past ◽  
The Everyday ◽  
Soviet Ideology ◽  
Almost All ◽  
Artistic Skill

The author explores ways to visualize the everyday life of the Brezhnev period’s soviet childhood in a Eugeniya Dvoskina’s drawings cycle «#forthosewhoremember». Comparing the artist’s work with other modern visual nostalgic projects, the significance of the selected source is justified: this cycle allows us to give an idea of the visual environment of the child, typical kinds of the children’s territory, public and private areas in the collective memory of the generation. Based on the methodology of visual sociology (P. Shtompka, O.V. Gavrishina), the author analyzes the reasons for the cycle’s perception of the older generation as uniquely “Soviet” and raises the question about markers of “Soviet childhood”. The universality and heritability of many children’s practices makes them timeless, so the design of the material world and symbols of Soviet ideology are main signs of the historical era. Compositional and graphic solutions of images play an important role for the viewer’s perception. Knowledge of nature and artistic skill allows the artist to create heroes with accurate behavioral characteristics and evokes, in addition to visual, almost all types of sensory memory (tactile, motor, audio). The use of accompaniment text, often in the form of speech formulas, is crucial for this effect. If we consider this cycle in the logic of S.”Boym’s reasoning about nostalgia, drawings about soviet childhood can be attributed to the procedural type of nostalgia, which is characterized by irony and contradictory attitude to the past. Eugeniya Dvoskina’s work provides a complex multi-faceted visualization of the everyday life of Soviet childhood in the 60–80s of the XX century.

Exoskeletons

2019 ◽  
pp. 234-259
Author(s):  
Priyanshu Agarwal ◽  
Ashish D. Deshpande
Keyword(s):  
Case Studies ◽  
Energy Efficient ◽  
Laboratory Testing ◽  
Human Performance ◽  
State Of The Art ◽  
Upper Body ◽  
The Past ◽  
The Future ◽  
Human Use ◽  
Exoskeleton Design

The past few decades have witnessed a rapid explosion in research surrounding robotic exoskeletons due to their promising applications in medicine and human performance augmentation. Several advances in technology have led to the development of more energy efficient and viable prototypes of these devices. However, despite this rapid advancement in exoskeleton technology, most of the developed devices are limited to laboratory testing and a very few of them are commercially available for human use. This chapter discusses the advances in various constituting technologies including actuation, sensing, materials, and controls that made exoskeleton research feasible. Also presented are case studies on two state-of-the-art robotic exoskeletons, Harmony and Maestro, developed for rehabilitation of the upper body. The chapter concludes with a discussion on the ongoing challenges in exoskeleton design and ethical, social, and legal considerations related to the use of these devices and the future of exoskeletons.

Evaluation of Algorithms for Combining Independent Data Sets in a Human Performance Expert System

1987 ◽  
Vol 31 (7) ◽  
pp. 811-814
Author(s):  
Valerie J. Gawron ◽  
David J. Travale ◽  
Colin Drury ◽  
Sara Czaja
Keyword(s):  
Reaction Time ◽  
Expert System ◽  
Human Performance ◽  
Test Procedure ◽  
Reaction Time Task ◽  
Error Rates ◽  
Task Completion ◽  
Data Sets ◽  
Independent Data ◽  
Independent Variables

A major problem facing system designers today is predicting human performance in: 1) systems that have not yet been built, 2) situations that have not yet been experienced, and 3) situations for which there are only anecdotal reports. To address this problem, the Human Performance Expert System (Human) was designed. The system contains a large data base of equations derived from human performance research reported in the open literature. Human accesses these data to predict task performance times, task completion probabilities, and error rates. A problem was encountered when multiple independent data sets were relevant to one task. For example, a designer is interested in the effects of luminance and front size on number of reading errors. Two data sets exist in the literature: one examining the effects of luminance, the other, font size. The data in the two sets were collected at different locations with different subjects and at different times in history. How can the two data sets be combined to address the designer's problem? Four combining algorithms were developed and then tested in two steps. In step one, two reaction-time experiments were conducted: one to evaluate the effect the number of alternatives on reaction time; the second, signals per minute and number of displays being monitored. The four algorithms were used on the data from these two experiments to predict reaction time in the situation where all three independent variables are manipulated simultaneously. In step two of the test procedure, a third experiment was conducted. Subjects who had not participated in either Experiment One or Two performed a reaction-time task under the combined effects of all three independent variables. The predictions made from step one were compared to the actual empirical data collected in step two. The results of these comparisons are presented.

A Lead-Lag Compensation Approach to Display/Control Gain for Touch Tablets

1986 ◽  
Vol 30 (4) ◽  
pp. 332-336 ◽  
Author(s):  
Jane A. Becker ◽  
Joel S. Greenstein
Keyword(s):  
Human Performance ◽  
Error Rates ◽  
Continuous Control ◽  
Acquisition Rate ◽  
Variable Gain ◽  
Control Gain ◽  
Compensation Approach ◽  
Display Control ◽  
Speed Accuracy ◽  
Lag Compensation

The display/control gain exhibited by a continuous control system strongly affects the human's ability to quickly and accurately operate the system. The primary objectives of this research were to develop and optimize a variable D/C gain that improves human performance with touch tablets. This variable gain moderates the speed-accuracy trade-off problem associated with traditional D/C gains. Empirical results indicate that a lead-lag compensator increased the target acquisition rate relative to a traditional D/C gain system. Error rates were low with both systems, but were greater with lead-lag compensation than in an uncompensated system. Tablet size did not appear to significantly affect performance.

AN APPEAL TO THE PRESIDENT OF THE UNITED STATES OF AMERICA AND THE CHAIRMAN OF THE PRESIDIUM OF THE U.S.S.R. SUPREME SOVIET

PEDIATRICS ◽  
1982 ◽  
Vol 70 (4) ◽  
pp. 581-581
Author(s):  
Keyword(s):  
Nuclear Weapons ◽  
Human Performance ◽  
The United States ◽  
Long Term Effects ◽  
Daily Work ◽  
The Past ◽  
The People ◽  
Military Systems ◽  
Simple Error

The growing threat of thermonuclear war and the continued development and proliferation of nuclear weapons have compelled us as physicians to examine in detail the consequences such a war would have on the people of our nations and of the world, whose health and survival are our professional commitment. During the past several days, physicians and scientists from 31 countries have gathered to consider relevant data on the immediate and long term effects of a nuclear conflict. We were unanimous in concluding that: . . . The growth in sheer numbers of nuclear weapons and the increasing complexity and sophistication of delivery systems increase the possibility that a nuclear conflict may be triggered by tragic accident. Physicians are aware from their daily work that technologic systems are liable to malfunction and that human performance may fail because of mental derangement or even simple error. Whereas such failures in medicine may jeopardise a single life, the malfunctioning of military systems may now endanger the existence of humanity....

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