scholarly journals The role of context in volitional control of feature-based attention.

2016 ◽  
Vol 42 (2) ◽  
pp. 213-224 ◽  
Author(s):  
Artem V. Belopolsky ◽  
Edward Awh
Keyword(s):  
Volitional Control ◽  
Feature Based

scholarly journals Halloysite nanotubes filled with salicylic acid and sodium diclofenac: effects of vacuum pumping on loading and release properties

2021 ◽  
Author(s):  
Lorenzo Lisuzzo ◽  
Giuseppe Cavallaro ◽  
Stefana Milioto ◽  
Giuseppe Lazzara
Keyword(s):  
Salicylic Acid ◽  
Release Kinetics ◽  
Halloysite Nanotubes ◽  
Drug Molecules ◽  
Sodium Diclofenac ◽  
Tunable Release ◽  
Feature Based ◽  
Kinetics Of ◽  
Filling Mechanism

AbstractIn this work, we investigated the effects of the vacuum pumping on both the loading efficiencies and the release kinetics of halloysite nanotubes filled with drug molecules dissolved in ethanol. As model drugs, salicylic acid and sodium diclofenac were selected. For comparison, the loading of the drug molecules was conducted on platy kaolinite to explore the key role of the hollow tubular morphology on the filling mechanism of halloysite. The effects of the pressure conditions used in the loading protocol were interpreted and discussed on the basis of the thermodynamic results provided by Knudsen thermogravimetry, which demonstrated the ethanol confinement inside the halloysite cavity. Several techniques (TEM, FTIR spectroscopy, DLS and $$\zeta$$ ζ -potential experiments) were employed to characterize the drug filled nanoclays. Besides, release kinetics of the drugs were studied and interpreted according to the loading mechanism. This work represents a further step for the development of nanotubular carriers with tunable release feature based on the loading protocol and drug localization into the carrier. Graphic abstract The filling efficiency of halloysite nanotubes is enhanced by the reduction of the pressure conditions used in the loading protocol.

scholarly journals The Role of Alpha Activity in Spatial and Feature-Based Attention

eNeuro ◽  
2016 ◽  
Vol 3 (5) ◽  
pp. ENEURO.0204-16.2016 ◽  
Author(s):  
Rosanne M. van Diepen ◽  
Lee M. Miller ◽  
Ali Mazaheri ◽  
Joy J. Geng
Keyword(s):  
Alpha Activity ◽  
Feature Based

scholarly journals The role of competing stimuli in feature-based attention

2010 ◽  
Vol 3 (9) ◽  
pp. 727-727
Author(s):  
M. Saenz ◽  
G. M Boynton
Keyword(s):  
Feature Based ◽  
Competing Stimuli

Pharyngeal swallowing elicited by fluid infusion: role of volition and vallecular containment

1996 ◽  
Vol 270 (2) ◽  
pp. G347-G354 ◽  
Author(s):  
P. Pouderoux ◽  
J. A. Logemann ◽  
P. J. Kahrilas
Keyword(s):  
Spatial Distribution ◽  
Infusion Rate ◽  
Volitional Control ◽  
Flow Rates ◽  
Fluid Infusion ◽  
Water Infusion ◽  
Pharyngeal Swallow ◽  
Pharyngeal Swallowing ◽  
Temperature Water

Nonalimentary swallows minimize aspiration by clearing accumulated fluid from the pharynx. This study aimed to define 1) the pharyngeal sensory field to elicit swallowing and 2) the effect of infusion rate, volition, taste, and temperature on pharyngeal swallows. Test solutions were directed into the valleculae at 6.5, 11.5, and 32 ml/min through a catheter in eight healthy volunteers. Deglutition was signaled with electromyography and electroglottography. Spatial distribution of infusate before swallowing was studied using videofluoroscopy coupled with a video timer. Volitional control was assessed with rapid or restrained swallows. Pharyngeal swallow latency decreased as the instillation rate increased, was potently modified with volition, and was unchanged by infusate taste or temperature. Water infusion into the valleculae did not trigger pharyngeal swallowing until liquids overflowed and reached the aryepiglottic folds or pyriform sinuses. The variation in swallow latency among flow rates was mainly due to the duration of liquid containment within the valleculae. This suggests that the valleculae act to contain pharyngeal secretions and residue and prevent aspiration by diverting their contents around the larynx before swallowing.

scholarly journals Understanding location- and feature-based processing along the human intraparietal sulcus

2016 ◽  
Vol 116 (3) ◽  
pp. 1488-1497 ◽  
Author(s):  
Katherine C. Bettencourt ◽  
Yaoda Xu
Keyword(s):  
Short Term Memory ◽  
Visual Cognition ◽  
Cognitive Tasks ◽  
Intraparietal Sulcus ◽  
Short Term ◽  
Object Individuation ◽  
Visual Short Term Memory ◽  
Feature Based ◽  
Partial Overlap

Based on different cognitive tasks and mapping methods, the human intraparietal sulcus (IPS) has been subdivided according to multiple different organizational schemes. The presence of topographically organized regions throughout IPS indicates a strong location-based processing in this brain region. However, visual short-term memory (VSTM) studies have shown that while a region in the inferior IPS region (inferior IPS) is involved in object individuation and selection based on location, a region in the superior IPS (superior IPS) primarily encodes and stores object featural information. Here, we determined the localization of these two VSTM IPS regions with respect to the topographic IPS regions in individual participants and the role of different IPS regions in location- and feature-based processing. Anatomically, inferior IPS showed an 85.2% overlap with topographic IPS regions, with the greatest overlap seen in V3A and V3B, and superior IPS showed a 73.6% overall overlap, with the greatest overlap seen in IPS0-2. Functionally, there appeared to be a partial overlap between IPS regions involved in location- and feature-based processing, with more inferior and medial regions showing a stronger location-based processing and more superior and lateral regions showing a stronger feature-based processing. Together, these results suggest that understanding the multiplex nature of IPS in visual cognition may not be reduced to examining the functions of the different IPS topographic regions, but rather, it can only be accomplished by understanding how regions identified by different tasks and methods may colocalize with each other.

scholarly journals The role of lightness, hue and saturation in feature-based visual attention

2014 ◽  
Vol 96 ◽  
pp. 25-32 ◽  
Author(s):  
Geoffrey W. Stuart ◽  
Wendy N. Barsdell ◽  
Ross H. Day
Keyword(s):  
Visual Attention ◽  
Feature Based

Reasoning Under Time Pressure

2009 ◽  
Vol 56 (2) ◽  
pp. 77-83 ◽  
Author(s):  
Jonathan St. B. T. Evans ◽  
Simon J. Handley ◽  
Alison M. Bacon
Keyword(s):  
Time Pressure ◽  
Syllogistic Reasoning ◽  
Conditional Inference ◽  
Belief Bias ◽  
Volitional Control ◽  
Logical Validity

In this study, we examine the role of beliefs in conditional inference in two experiments, demonstrating a robust tendency for people to make fewer inferences from statements they disbelieve, regardless of logical validity. The main purpose of this study was to test whether participants are able to inhibit this belief effect where it constitutes a bias. This is the case when participants are specifically instructed to assume the truth of the premises. However, Experiment 1 showed that the effect is no less marked than when this instruction is given, than when it is not, although higher ability participants did show slightly less influence of belief (Experiment 2). Contrary to the findings with syllogistic reasoning, use of speeded tasks had no effect on the extent of the belief bias (both experiments), although it did considerably reduce the numbers of inferences that were drawn overall. These findings suggest that the belief bias in conditional inference is less open to volitional control than that associated with syllogistic reasoning.

scholarly journals ROLE OF TIE-POINTS DISTRIBUTION IN AERIAL PHOTOGRAPHY

2016 ◽  
Vol XL-3/W4 ◽  
pp. 41-44
Author(s):  
S. Kerner ◽  
I. Kaufman ◽  
Y. Raizman
Keyword(s):  
Feature Extraction ◽  
Spatial Distribution ◽  
Aerial Photography ◽  
Image Matching ◽  
Feature Matching ◽  
Real Data ◽  
Matching Process ◽  
Feature Based ◽  
Extraction Stage

Automatic image matching algorithms, and especially feature-based methods, profoundly changed our understanding and requirements of tie points. The number of tie points has increased by orders of magnitude, yet the notions of accuracy and reliability of tie points remain equally important. The spatial distribution of tie points is less predictable, and is subject only to limited control. Feature-based methods also highlighted a conceptual division of the matching process into two separate stages – feature extraction and feature matching. <br><br> In this paper we discuss whether spatial distribution requirements, such as Von Gruber positions, are still relevant to modern matching methods. We argue that forcing such patterns might no longer be required in the feature extraction stage. However, we claim spatial distribution is important in the feature matching stage. <br><br> We will focus on terrains that are notorious for difficult matching, such as water bodies, with real data obtained by users of VisionMap’s A3 Edge camera and LightSpeed photogrammetric suite.

scholarly journals Ocular tracking responses to background motion gated by feature-based attention

2014 ◽  
Vol 112 (5) ◽  
pp. 1074-1081 ◽  
Author(s):  
David Souto ◽  
Dirk Kerzel
Keyword(s):  
Peak Velocity ◽  
Horizontal Direction ◽  
Motion Onset ◽  
Motion Direction ◽  
Ocular Tracking ◽  
Feature Based ◽  
Background Motion ◽  
Ocular Following Response ◽  
Tracking Response

Involuntary ocular tracking responses to background motion offer a window on the dynamics of motion computations. In contrast to spatial attention, we know little about the role of feature-based attention in determining this ocular response. To probe feature-based effects of background motion on involuntary eye movements, we presented human observers with a balanced background perturbation. Two clouds of dots moved in opposite vertical directions while observers tracked a target moving in horizontal direction. Additionally, they had to discriminate a change in the direction of motion (±10° from vertical) of one of the clouds. A vertical ocular following response occurred in response to the motion of the attended cloud. When motion selection was based on motion direction and color of the dots, the peak velocity of the tracking response was 30% of the tracking response elicited in a single task with only one direction of background motion. In two other experiments, we tested the effect of the perturbation when motion selection was based on color, by having motion direction vary unpredictably, or on motion direction alone. Although the gain of pursuit in the horizontal direction was significantly reduced in all experiments, indicating a trade-off between perceptual and oculomotor tasks, ocular responses to perturbations were only observed when selection was based on both motion direction and color. It appears that selection by motion direction can only be effective for driving ocular tracking when the relevant elements can be segregated before motion onset.

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