scholarly journals Saccadic eye movements are deployed faster for salient facial stimuli, but are relatively indifferent to their emotional content

2021 ◽  
Author(s):  
Abigail Webb ◽  
Jordi M Asher ◽  
Paul Hibbard
Keyword(s):  
Spatial Frequency ◽  
Response Times ◽  
Saccadic Eye Movements ◽  
Threat Bias ◽  
Facial Stimuli ◽  
Facial Information ◽  
Naturally Occurring ◽  
Socially Relevant ◽  
Saccadic Responses

The present study explores the threat bias for fearful facial expressions using saccadic latency as the response mode, with a particular focus on the role of low-level facial information, including spatial frequency, physical contrast, and apparent, perceived contrast. In a simple localisation task, participants were presented with spatially-filtered versions of neutral, fearful, angry and happy faces. Faces were either composed of naturally-occurring, expression-related differences in contrast, normalised for RMS contrast, or normalised for their apparent, perceived contrast. Together, findings show that saccadic responses are not biased toward fearful expressions compared to neutral, angry or happy counterparts, regardless of their spatial frequency content. Saccadic response times are, however, significantly influenced by the physical contrast of facial stimuli, and the extent to which these are preserved or normalised at the physical (RMS matched) and psychophysical (perceptually matched) level. We discuss the implications of findings for the threat bias literature, and the extent to which image processing can be expected to influence behavioural responses to socially-relevant facial stimuli.

scholarly journals The role of fixation disengagement in the parallel programming of sequences of saccades

2019 ◽  
Vol 237 (11) ◽  
pp. 3033-3045
Author(s):  
Eugene McSorley ◽  
Iain D. Gilchrist ◽  
Rachel McCloy
Keyword(s):  
Eye Movements ◽  
Parallel Programming ◽  
Response Times ◽  
Saccadic Eye Movements ◽  
Gap Effect ◽  
Task Completion ◽  
Published Data ◽  
Trial Duration ◽  
Visual Tasks

Abstract One of the core mechanisms involved in the control of saccade responses to selected target stimuli is the disengagement from the current fixation location, so that the next saccade can be executed. To carry out everyday visual tasks, we make multiple eye movements that can be programmed in parallel. However, the role of disengagement in the parallel programming of saccades has not been examined. It is well established that the need for disengagement slows down saccadic response time. This may be important in allowing the system to program accurate eye movements and have a role to play in the control of multiple eye movements but as yet this remains untested. Here, we report two experiments that seek to examine whether fixation disengagement reduces saccade latencies when the task completion demands multiple saccade responses. A saccade contingent paradigm was employed and participants were asked to execute saccadic eye movements to a series of seven targets while manipulating when these targets were shown. This both promotes fixation disengagement and controls the extent that parallel programming can occur. We found that trial duration decreased as more targets were made available prior to fixation: this was a result both of a reduction in the number of saccades being executed and in their saccade latencies. This supports the view that even when fixation disengagement is not required, parallel programming of multiple sequential saccadic eye movements is still present. By comparison with previous published data, we demonstrate a substantial speeded of response times in these condition (“a gap effect”) and that parallel programming is attenuated in these conditions.

scholarly journals Title: Suppression durations for facial expressions under breaking continuous flash suppression: effects of faces’ low-level image properties.

2020 ◽  
Author(s):  
Abigail Webb ◽  
Paul Hibbard
Keyword(s):  
Spatial Frequency ◽  
Facial Expressions ◽  
Combined Effects ◽  
Frequency Content ◽  
Limited Evidence ◽  
Continuous Flash Suppression ◽  
Low Level ◽  
Facial Stimuli ◽  
Suppression Effects

Perceptual biases for fearful facial expressions are observed across many studies. According to the low-level, visual-based account of these biases, fear expressions are advantaged in some way due to their image properties, such as low spatial frequency content. Breaking continuous flash suppression (b-CFS) has explored these effects, and demonstrated similar biases for detecting fearful facial expressions. However, there is a degree of empirical disagreement regarding the range of spatial frequency content. Recent findings from a b-CFS study highlight the role of high, rather than low spatial frequency content in determining faces’ visibility. The present study contributes to ongoing discussions regarding the efficacy of b-CFS, and shows that the visibility of facial expressions varies according to how faces are normalised for physical contrast and spatially filtered. Findings show limited evidence of a bias for detecting fearful facial expressions, but importantly, they show that such biases are less likely to occur when faces are normalised for apparent, perceived contrast, compared to physical contrast. Together these findings further the current understanding of the combined effects of spatial frequency and contrast on face visibility under b-CFS, and raise important questions regarding procedures used to standardise facial stimuli.

scholarly journals The effect of directional social cues on saccadic eye movements in Parkinson’s disease

2021 ◽  
Author(s):  
Koray Koçoğlu ◽  
Gülden Akdal ◽  
Berril Dönmez Çolakoğlu ◽  
Raif Çakmur ◽  
Jagdish C. Sharma ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Response Times ◽  
Eye Gaze ◽  
Saccadic Eye Movements ◽  
Social Cues ◽  
Cueing Task ◽  
Anticipatory Errors ◽  
Socially Relevant ◽  
The Right

AbstractThere is growing interest in how social processes and behaviour might be affected in Parkinson’s disease. A task which has been widely used to assess how people orient attention in response to social cues is the spatial cueing task. Socially relevant directional cues, such as a picture of someone gazing or pointing to the left or the right have been shown to cause orienting of visual attention in the cued direction. The basal ganglia may play a role in responding to such directional cues, but no studies to date have examined whether similar social cueing effects are seen in people with Parkinson’s disease. In this study, patients and healthy controls completed a prosaccade (Experiment 1) and an antisaccade task (Experiment 2) in which the target was preceded by arrow, eye gaze or pointing finger cues. Patients showed increased errors and response times for antisaccades but not prosaccades. Healthy participants made most anticipatory errors on pointing finger cue trials, but Parkinson's patients were equally affected by arrow, eye gaze and pointing cues. It is concluded that Parkinson's patients have a reduced ability to suppress responding to directional cues, but this effect is not specific to social cues.

Fine structure and properties of defects in naturally occurring silicates and oxides

1990 ◽  
Vol 48 (4) ◽  
pp. 460-461
Author(s):  
David R. Veblen
Keyword(s):  
Chemical Reactions ◽  
High Resolution Electron Microscopy ◽  
Extended Defects ◽  
Single Chain ◽  
Naturally Occurring ◽  
Resolution Electron ◽  
Fine Structures ◽  
Image Simulations ◽  
Similar Crystal Structure

Extended defects and interfaces control many processes in rock-forming minerals, from chemical reactions to rock deformation. In many cases, it is not the average structure of a defect or interface that is most important, but rather the structure of defect terminations or offsets in an interface. One of the major thrusts of high-resolution electron microscopy in the earth sciences has been to identify the role of defect fine structures in reactions and to determine the structures of such features. This paper will review studies using HREM and image simulations to determine the structures of defects in silicate and oxide minerals and present several examples of the role of defects in mineral chemical reactions. In some cases, the geological occurrence can be used to constrain the diffusional properties of defects.The simplest reactions in minerals involve exsolution (precipitation) of one mineral from another with a similar crystal structure, and pyroxenes (single-chain silicates) provide a good example. Although conventional TEM studies have led to a basic understanding of this sort of phase separation in pyroxenes via spinodal decomposition or nucleation and growth, HREM has provided a much more detailed appreciation of the processes involved.

Suva Residents’ Views on Cancer, Diabetes and HIV in The Fiji Times

2020 ◽  
Vol 40 (1) ◽  
Author(s):  
Farzana Gounder
Keyword(s):  
Chronic Illnesses ◽  
Structural Reforms ◽  
Letters To The Editor ◽  
Medical Responsibility ◽  
Grassroots Support ◽  
Preliminary Study ◽  
Socially Relevant ◽  
Situated Approach ◽  
Significant Health

The burden of preventable diseases is increasing in the South Pacific Island Countries and Territories. In Fiji, significant media attention and national finances are spent on public dissemination of the modifiable risk factors of chronic illnesses. However, little is known about lay societal perceptions of chronic illnesses and of people living with these illnesses. This preliminary study takes an area-situated approach to lay knowledge and examines Suva residents’ moral evaluations associated with socially significant health concerns in Fiji. Using the case studies of HIV, cancer, and diabetes, the research employs content analysis to examine 144 Suva residents’ Letters to the Editor, published between 2000 and 2019 in The Fiji Times. The findings indicate that letter writers on chronic illnesses are power sensitive, interested in governmental responsibility, and aware of the role of stigma in creating inequitable health outcomes. The study’s findings locate chronic illness as not only a medical responsibility but also a social justice and human rights concern that requires a multisectoral approach, with community-tailored responses at the heart of all discussions. The lay-societal recognition of the three illnesses as being socially relevant suggests grassroots support for policies directed towards structural reforms for the prevention and management of these illnesses.

Role of Flavonoids in Neurodegenerative Disorders with Special Emphasis on Tangeritin

2019 ◽  
Vol 18 (8) ◽  
pp. 581-597 ◽  
Author(s):  
Ambreen Fatima ◽  
Yasir Hasan Siddique
Keyword(s):  
Medicinal Plants ◽  
Mechanism Of Action ◽  
Neurodegenerative Disorders ◽  
Treatment Strategies ◽  
Dietary Supplementation ◽  
Plant Polyphenols ◽  
Promising Candidate ◽  
Naturally Occurring ◽  
The Brain

Flavonoids are naturally occurring plant polyphenols found universally in all fruits, vegetables and medicinal plants. They have emerged as a promising candidate in the formulation of treatment strategies for various neurodegenerative disorders. The use of flavonoid rich plant extracts and food in dietary supplementation have shown favourable outcomes. The present review describes the types, properties and metabolism of flavonoids. Neuroprotective role of various flavonoids and the possible mechanism of action in the brain against the neurodegeneration have been described in detail with special emphasis on the tangeritin.

Monosodium Glutamate Toxicity and the Possible Protective Role of L–Carnitine

2018 ◽  
Vol 6 (1) ◽  
pp. 45-56
Author(s):  
Lalrinzuali Sailo ◽  
◽  
Meesala Krishna Murthy ◽  
Khandayataray Pratima ◽  
Vikas Kumar Roy ◽  
...  
Keyword(s):  
Human Subjects ◽  
Monosodium Glutamate ◽  
Essential Amino Acids ◽  
Protective Role ◽  
Glutamate Toxicity ◽  
Common Salt ◽  
Genotoxic Effects ◽  
Naturally Occurring ◽  
Flavour Enhancer

Monosodium glutamate is naturally available non-essential amino acids, which found in naturally occurring foods and used as flavour enhancer worldwide. Monosodium glutamate is believed to be linked with diverse health problems. The aim of the study was toxic effects of monosodium glutamate (MSG) and the protective role of L-carnitine, light on the available literature from last 25 years about diverse toxicity studies which had been carried out on animal and human models. Google scholar, NCBI, PUBMED, EMBASE, Wangfang databases, and Web of Science databases were used to retrieve the available studies. MSG was linked with deleterious effects particularly in animals including induction of obesity, diabetes, hepatotoxic, neurotoxic and genotoxic effects showed in Literature. Few reports revealed increased hunger, food intake, and obesity in human subjects due to MSG consumption. Hepatotoxic, neurotoxic, and genotoxic effects of monosodium glutamate on humans carried out very limitedly. High consumption of monosodium glutamate may be linked with harmful health effects showed in available literatures. So, it is recommended to use common salt instead of MSG. Furthermore, intensive research is required to explore monosodium glutamate–related molecular and metabolic mechanisms. L-carnitine can protect from Hepatotoxic, neurotoxic, renal impairment and genotoxic effects functionally, biochemically and histopathologically with a corresponding reduction of oxidative stress.

How Artefacts Do Leadership: A Ventriloquial Analysis

2021 ◽  
pp. 089331892199807
Author(s):  
Jonathan Clifton ◽  
Fernando Fachin ◽  
François Cooren
Keyword(s):  
Organizational Communication ◽  
Recent Work ◽  
Distributed Leadership ◽  
Network Theory ◽  
Actor Network Theory ◽  
Fine Grained ◽  
Naturally Occurring ◽  
Human Actors

To date there has been little work that uses fine-grained interactional analyses of the in situ doing of leadership to make visible the role of non-human as well as human actants in this process. Using transcripts of naturally-occurring interaction as data, this study seeks to show how leadership is co-achieved by artefacts as an in-situ accomplishment. To do this we situate this study within recent work on distributed leadership and argue that it is not only distributed across human actors, but also across networks that include both human and non-human actors. Taking a discursive approach to leadership, we draw on Actor Network Theory and adopt a ventriloquial approach to sociomateriality as inspired by the Montreal School of organizational communication. Findings indicate that artefacts “do” leadership when a hybrid presence is made relevant to the interaction and when this presence provides authoritative grounds for influencing others to achieve the group’s goals.

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