scholarly journals Mental imagery of object motion in weightlessness

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Silvio Gravano ◽  
Francesco Lacquaniti ◽  
Myrka Zago
Keyword(s):  
Mental Imagery ◽  
Object Motion ◽  
Front Wall ◽  
Gravity Level ◽  
Dynamic Interactions ◽  
Vestibular Cortex ◽  
Fine Grained ◽  
Condition Versus ◽  
Spatial Features ◽  
Spatiotemporal Parameters

AbstractMental imagery represents a potential countermeasure for sensorimotor and cognitive dysfunctions due to spaceflight. It might help train people to deal with conditions unique to spaceflight. Thus, dynamic interactions with the inertial motion of weightless objects are only experienced in weightlessness but can be simulated on Earth using mental imagery. Such training might overcome the problem of calibrating fine-grained hand forces and estimating the spatiotemporal parameters of the resulting object motion. Here, a group of astronauts grasped an imaginary ball, threw it against the ceiling or the front wall, and caught it after the bounce, during pre-flight, in-flight, and post-flight experiments. They varied the throwing speed across trials and imagined that the ball moved under Earth’s gravity or weightlessness. We found that the astronauts were able to reproduce qualitative differences between inertial and gravitational motion already on ground, and further adapted their behavior during spaceflight. Thus, they adjusted the throwing speed and the catching time, equivalent to the duration of virtual ball motion, as a function of the imaginary 0 g condition versus the imaginary 1 g condition. Arm kinematics of the frontal throws further revealed a differential processing of imagined gravity level in terms of the spatial features of the arm and virtual ball trajectories. We suggest that protocols of this kind may facilitate sensorimotor adaptation and help tuning vestibular plasticity in-flight, since mental imagery of gravitational motion is known to engage the vestibular cortex.

Perceptual Representations and the Vividness of Stimulus-Triggered and Stimulus-Independent Experiences

2020 ◽  
Vol 15 (5) ◽  
pp. 1200-1213 ◽  
Author(s):  
Peter Fazekas ◽  
Georgina Nemeth ◽  
Morten Overgaard
Keyword(s):  
Working Memory ◽  
Mental Imagery ◽  
Information Exchange ◽  
Activity Patterns ◽  
Mind Wandering ◽  
Brain Regions ◽  
Neural Basis ◽  
Fine Grained ◽  
Common Framework ◽  
Cortical Regions

In recent years, researchers from independent subfields have begun to engage with the idea that the same cortical regions that contribute to on-line perception are recruited during and underlie off-line activities such as information maintenance in working memory, mental imagery, hallucinations, dreaming, and mind wandering. Accumulating evidence suggests that in all of these cases the activity of posterior brain regions provides the contents of experiences. This article is intended to move one step further by exploring specific links between the vividness of experiences, which is a characteristic feature of consciousness regardless of its actual content, and certain properties of the content-specific neural-activity patterns. Investigating the mechanisms that underlie mental imagery and its relation to working memory and the processes responsible for mind wandering and its similarities to dreaming form two clusters of research that are in the forefront of the recent scientific study of mental phenomena, yet communication between these two clusters has been surprisingly sparse. Here our aim is to foster such information exchange by articulating a hypothesis about the fine-grained phenomenological structure determining subjective vividness and its possible neural basis that allows us to shed new light on these mental phenomena by bringing them under a common framework.

Representing Emotions as Dynamic Interactions of Symbols

2015 ◽  
pp. 83-101
Author(s):  
Andra Băltoiu ◽  
Cătălin Buiu
Keyword(s):  
Dynamical System ◽  
Mental Imagery ◽  
Formal Model ◽  
Literary Texts ◽  
Automatic Method ◽  
Dynamic Interactions ◽  
Internal Representations ◽  
Emotional Processes ◽  
Analytic Psychology ◽  
Different Levels

This chapter proposes an emotional architecture organized around three pairs of antithetic universal symbols, or archetypes, derived from analytic psychology and anthropological accounts of mythical thinking. Their functions, relationships and interactions, on different levels of complexity within a dynamical system that mimics human emotional processes, are described by a formal model and a constructed ontology. The aim of the model is characterizing symbolic reasoning and figurative and analogue mechanisms of mental imagery associated with the internal representations of events. An automatic method for metaphor recognition and interpretation is proposed, targeting the identification of the proposed universal symbols in literary texts.

scholarly journals Moral Dynamics: Grounding Moral Judgment in Intuitive Physics and Intuitive Psychology

2021 ◽  
Author(s):  
Felix Sosa ◽  
Tomer David Ullman ◽  
Joshua Tenenbaum ◽  
Samuel J. Gershman ◽  
Tobias Gerstenberg
Keyword(s):  
Moral Judgment ◽  
Moral Psychology ◽  
Visual Stimuli ◽  
Mental States ◽  
Moral Judgments ◽  
Visual Features ◽  
Dynamic Interactions ◽  
Fine Grained ◽  
Intuitive Physics ◽  
Intuitive Theory

When holding others morally responsible, we care about what they did, and what they thought. Traditionally, research in moral psychology has relied on vignette studies, in which a protagonist's actions and thoughts are explicitly communicated. While this research has revealed what variables are important for moral judgment, such as actions and intentions, it is limited in providing a more detailed understanding of exactly how these variables affect moral judgment. Using dynamic visual stimuli that allow for a more fine-grained experimental control, recent studies have proposed a direct mapping from visual features to moral judgments. We embrace the use of visual stimuli in moral psychology, but question the plausibility of a feature-based theory of moral judgment. We propose that the connection from visual features to moral judgments is mediated by an inference about what the observed action reveals about the agent's mental states, and what causal role the agent's action played in bringing about the outcome. We present a computational model that formalizes moral judgments of agents in visual scenes as computations over an intuitive theory of physics combined with an intuitive theory of mind. We test the model's quantitative predictions in three experiments across a wide variety of dynamic interactions between agent and patient.

scholarly journals Sensory convergence in the parieto-insular vestibular cortex

2014 ◽  
Vol 111 (12) ◽  
pp. 2445-2464 ◽  
Author(s):  
Michael E. Shinder ◽  
Shawn D. Newlands
Keyword(s):  
Visual Target ◽  
Rhesus Macaques ◽  
Insular Cortex ◽  
Object Motion ◽  
Visual Object ◽  
Vestibular Cortex ◽  
Combined Movements ◽  
Sensory Convergence ◽  
The Central Nervous System ◽  
The Individual

Vestibular signals are pervasive throughout the central nervous system, including the cortex, where they likely play different roles than they do in the better studied brainstem. Little is known about the parieto-insular vestibular cortex (PIVC), an area of the cortex with prominent vestibular inputs. Neural activity was recorded in the PIVC of rhesus macaques during combinations of head, body, and visual target rotations. Activity of many PIVC neurons was correlated with the motion of the head in space (vestibular), the twist of the neck (proprioceptive), and the motion of a visual target, but was not associated with eye movement. PIVC neurons responded most commonly to more than one stimulus, and responses to combined movements could often be approximated by a combination of the individual sensitivities to head, neck, and target motion. The pattern of visual, vestibular, and somatic sensitivities on PIVC neurons displayed a continuous range, with some cells strongly responding to one or two of the stimulus modalities while other cells responded to any type of motion equivalently. The PIVC contains multisensory convergence of self-motion cues with external visual object motion information, such that neurons do not represent a specific transformation of any one sensory input. Instead, the PIVC neuron population may define the movement of head, body, and external visual objects in space and relative to one another. This comparison of self and external movement is consistent with insular cortex functions related to monitoring and explains many disparate findings of previous studies.

scholarly journals MRDA-MGFSNet: Network Based on a Multi-Rate Dilated Attention Mechanism and Multi-Granularity Feature Sharer for Image-Based Butterflies Fine-Grained Classification

Symmetry ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1351
Author(s):  
Maopeng Li ◽  
Guoxiong Zhou ◽  
Weiwei Cai ◽  
Jiayong Li ◽  
Mingxuan Li ◽  
...  
Keyword(s):  
Receptive Fields ◽  
Attention Mechanism ◽  
Good Effect ◽  
Complex Environment ◽  
High Background ◽  
Symmetrical Structure ◽  
Fine Grained ◽  
Multi Scale ◽  
Spatial Features

Aiming at solving the problems of high background complexity of some butterfly images and the difficulty in identifying them caused by their small inter-class variance, we propose a new fine-grained butterfly classification architecture, called Network based on Multi-rate Dilated Attention Mechanism and Multi-granularity Feature Sharer (MRDA-MGFSNet). First, in this network, in order to effectively identify similar patterns between butterflies and suppress the information that is similar to the butterfly’s features in the background but is invalid, a Multi-rate Dilated Attention Mechanism (MRDA) with a symmetrical structure which assigns different weights to channel and spatial features is designed. Second, fusing the multi-scale receptive field module with the depthwise separable convolution module, a Multi-granularity Feature Sharer (MGFS), which can better solve the recognition problem of a small inter-class variance and reduce the increase in parameters caused by multi-scale receptive fields, is proposed. In order to verify the feasibility and effectiveness of the model in a complex environment, compared with the existing methods, our proposed method obtained a mAP of 96.64%, and an F1 value of 95.44%, which showed that the method proposed in this paper has a good effect on the fine-grained classification of butterflies.

Fine-Grained Ontology Reconstruction for Crisis Knowledge Based on Integrated Analysis of Temporal-Spatial Factors

2021 ◽  
Vol 48 (1) ◽  
pp. 24-41
Author(s):  
Xiaoyue Ma ◽  
Xue Pengzhen ◽  
Nada Matta ◽  
Qiang Chen
Keyword(s):  
Emergency Response ◽  
Temporal Relationship ◽  
Spatial Relationship ◽  
Integrated Analysis ◽  
Semantic Relationship ◽  
Real Situation ◽  
Fine Grained ◽  
Knowledge Based ◽  
Spatial Features ◽  
Dynamic Factors

Previous studies on crisis know­ledge organization mostly focused on the categorization of crisis know­ledge without regarding its dynamic trend and temporal-spatial features. In order to emphasize the dynamic factors of crisis collaboration, a fine-grained crisis know­ledge model is proposed by integrating temporal-spatial analysis based on ontology, which is one of the commonly used methods for know­ledge organization. The reconstruction of ontology-based crisis know­ledge will be implemented through three steps: analyzing temporal-spatial features of crisis know­ledge, reconstructing crisis know­ledge ontology, and verifying the temporal-spatial ontology. In the process of ontology reconstruction, the main classes and properties of the domain will be identified by investigating the crisis information resources. Meanwhile the fine-grained crisis ontology will be achieved at the level of characteristic representation of crisis know­ledge including temporal relationship, spatial relationship, and semantic relationship. Finally, we conducted case addition and system implementation to verify our crisis know­ledge model. This ontology-based know­ledge organization method theoretically optimizes the static organizational structure of crisis know­ledge, improving the flexibility of know­ledge organization and efficiency of emergency response. In practice, the proposed fine-grained ontology is supposed to be more in line with the real situation of emergency collaboration and management. Moreover, it will also provide the know­ledge base for decision-making during rescue process.

Correlative light microscopy, electron microscopy, and cytochemistry of cytoskeletal structures in motile fibroblasts

1991 ◽  
Vol 49 ◽  
pp. 168-169
Author(s):  
Julian P. Heath ◽  
Donna Turner ◽  
Bruce F. Holifield
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Differential Interference Contrast Microscopy ◽  
Dynamic Interactions ◽  
Fine Grained ◽  
Motile Cells ◽  
Contrast Microscopy ◽  
Carbon Coated ◽  
Interference Contrast Microscopy ◽  
Triton X

Contrast-enhanced video differential interference contrast microscopy (VDICM) is revealing new details about the dynamics of F-actin assemblies in motile cells. We are using correlative single cell light and electron microscopy and immunocytochemistry to understand the dynamic interactions of the actin cytoskeleton in lamellipodia and the leading lamella.Fibroblasts were cultured on carbon-coated glass #1 coverslips and examined on a Zeiss Axiophot. Cells were perfused with 1% glutaraldehyde (GA) in PIPES buffer and fixed for 15 min., quenched with 1 mg/ml borohydride/PBS and extracted with 0.1% Triton X-100 in PBS for 1 min. Cell postions were marked with a diamond objective, and the cells were incubated for 30 min. with 0.6 uM rhodamine-conjugated phalloidin to stain for F-actin. Light and fluorescence micrographs were taken on fine-grained film. After photography, cells were further fixed in 2.5% GA, postfixed in 1% osmium, dehydrated in ethanol and embedded in Spurrs resin. The glass was removed by scoring with a diamond pencil followed by immersion in liquid N2. Cells were relocated in the blocks by phase-contrast microscopy. Thin (80 nm) sections were examined in Philips EM 410 at 60 kV on a dicentric goniometric stage.

An Integrated CNN Model for Reconstructing and Predicting Land Use/Cover Change: A Case Study of the Baicheng Area, Northeast China

2021 ◽  
Vol 13 (23) ◽  
pp. 4846
Author(s):  
Yubo Zhang ◽  
Jiuchun Yang ◽  
Dongyan Wang ◽  
Jing Wang ◽  
Lingxue Yu ◽  
...  
Keyword(s):  
Land Use ◽  
High Precision ◽  
Northeast China ◽  
Prediction Models ◽  
Management Strategies ◽  
Global Environmental Change ◽  
Climate Impact ◽  
Fine Grained ◽  
Land System ◽  
Spatial Features

Land use and land cover change (LUCC) modeling has continuously been a major research theme in the field of land system science, which interprets the causes and consequences of land use dynamics. In particular, models that can obtain long-term land use data with high precision are of great value in research on global environmental change and climate impact, as land use data are important model input parameters for evaluating the effect of human activity on nature. However, the accuracy of existing reconstruction and prediction models is inadequate. In this context, this study proposes an integrated convolutional neural network (CNN) LUCC reconstruction and prediction model (CLRPM), which meets the demand for fine-scale LUCC reconstruction and prediction. This model applies the deep learning method, which far exceeds the performance of traditional machine learning methods, and uses CNN to extract spatial features and provide greater proximity information. Taking Baicheng city in Northeast China as an example, we verify that CLRPM achieved high-precision annual LUCC reconstruction and prediction, with an overall accuracy rate 9.38% higher than that of the existing models. Additionally, the error rate was reduced by 49.5%. Moreover, this model can perform multilevel LUCC classification category reconstructions and predictions. This study casts light on LUCC models within the high-precision and fine-grained LUCC categories, which will aid LUCC analyses and help decision-makers better understand complex land-use systems and develop better land management strategies.

scholarly journals Visual-vestibular processing in the human Sylvian fissure

2016 ◽  
Vol 116 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Sebastian M. Frank ◽  
Anna Maria Wirth ◽  
Mark W. Greenlee
Keyword(s):  
Insular Cortex ◽  
Vestibular Stimulation ◽  
Object Motion ◽  
Sylvian Fissure ◽  
Visual Object ◽  
Vestibular Cortex ◽  
Cortical Organization ◽  
Caloric Vestibular Stimulation ◽  
Cortex Area ◽  
And Function

Unlike other sensory systems, the cortical organization of the human vestibular system is not well established. A central role is assumed for the region of the posterior Sylvian fissure, close to the posterior insula. At this site, activation during vestibular stimulation has been observed in previous imaging studies and labeled as the parieto-insular vestibular cortex area (PIVC). However, vestibular responses are found in other parts of the Sylvian fissure as well, including a region that is referred to as the posterior insular cortex (PIC). The anatomical and functional relationship between PIC and PIVC is still poorly understood, because both areas have never been compared in the same participants. Therefore, to better understand the apparently more complex organization of vestibular cortex in the Sylvian fissure, we employed caloric and visual object motion stimuli during functional magnetic resonance imaging and compared location and function of PIVC and PIC in the same participants. Both regions responded to caloric vestibular stimulation, but only the activation pattern in right PIVC reliably represented the direction of the caloric stimulus. Conversely, activity in PIVC was suppressed during stimulation with visual object motion, whereas PIC showed activation. Area PIC is located at a more posterior site in the Sylvian fissure than PIVC. Our results suggest that PIVC and PIC should be considered separate areas in the vestibular Sylvian network, both in terms of location and function.

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