scholarly journals How Does Spatial Attention Influence the Probability and Fidelity of Colour Perception?

Vision ◽  
2019 ◽  
Vol 3 (2) ◽  
pp. 31
Author(s):  
Austin J. Hurst ◽  
Michael A. Lawrence ◽  
Raymond M. Klein
Keyword(s):  
Spatial Attention ◽  
Mixed Model ◽  
Stimulus Onset ◽  
Voluntary Attention ◽  
Colour Perception ◽  
Mixed Model Analysis ◽  
Continuous Response ◽  
Exogenous Cueing ◽  
Exogenous Cues ◽  
Onset Asynchrony

Existing research has found that spatial attention alters how various stimulus properties are perceived (e.g., luminance, saturation), but few have explored whether it improves the accuracy of perception. To address this question, we performed two experiments using modified Posner cueing tasks, wherein participants made speeded detection responses to peripheral colour targets and then indicated their perceived colours on a colour wheel. In E1, cues were central and endogenous (i.e., prompted voluntary attention) and the interval between cues and targets (stimulus onset asynchrony, or SOA) was always 800 ms. In E2, cues were peripheral and exogenous (i.e., captured attention involuntarily) and the SOA varied between short (100 ms) and long (800 ms). A Bayesian mixed-model analysis was used to isolate the effects of attention on the probability and the fidelity of colour encoding. Both endogenous and short-SOA exogenous spatial cueing improved the probability of encoding the colour of targets. Improved fidelity of encoding was observed in the endogenous but not in the exogenous cueing paradigm. With exogenous cues, inhibition of return (IOR) was observed in both RT and probability at the long SOA. Overall, our findings reinforce the utility of continuous response variables in the research of attention.

The Effects of Coarseness of Quantisation, Exposure Duration, and Selective Spatial Attention on the Perception of Spatially Quantised (‘Blocked’) Visual Images

Perception ◽  
1997 ◽  
Vol 26 (9) ◽  
pp. 1181-1196 ◽  
Author(s):  
Talis Bachmann ◽  
Neeme Kahusk
Keyword(s):  
Spatial Attention ◽  
Time Course ◽  
Spatial Scales ◽  
Stimulus Onset ◽  
Visual Images ◽  
Attentional Processing ◽  
Abrupt Decrease ◽  
A Minor ◽  
Onset Asynchrony ◽  
Coarse To Fine

The two objectives of the present article are (a) to present a brief overview of the effects of systematic variation of the spatial-scale value of quantisation and stimulus duration on the identification of original images that have been degraded by Harmon–Julesz type of image pixelisation by ‘blocking’ and (b) to report the results of two experiments where the effects of selective spatial precuing by local and global peripheral precues on the identification of quantised target stimuli have been studied. Both the overview and the new results reported here demonstrate some counterintuitive effects: (1) abrupt decrease in identification efficiency with only a minor change in the coarseness of quantisation over a critical value of pixels per stimulus; (2) a cost for valid attentional precuing with coarse-quantised images. If physical precues (exposed with stimulus onset asynchrony of 120 ms) were employed in order to orient spatial attention to perceive original or fine-quantised stimuli, then attentional facilitation was found. However, if the precued stimuli were coarse quantised then the facilitative effect crossed over to a detrimental effect of attention. These effects are discussed in the context of the microgenetic approach that presupposes the existence of a perceptual–attentional processing routine that operates according to the coarse-to-fine time-course rule of selective attentional activation of stimulus representations at various spatial scales.

Orienting and Focusing in Voluntary and Involuntary Visuospatial Attention Conditions

2010 ◽  
Vol 24 (3) ◽  
pp. 198-209 ◽  
Author(s):  
Yan Wang ◽  
Jianhui Wu ◽  
Shimin Fu ◽  
Yuejia Luo
Keyword(s):  
Gain Control ◽  
Event Related Potentials ◽  
Stimulus Onset ◽  
Orientation Discrimination ◽  
Involuntary Attention ◽  
Attention Condition ◽  
Voluntary Attention ◽  
Visual Spatial ◽  
Related Potentials ◽  
Underlying Mechanisms

In the present study, we used event-related potentials (ERPs) and behavioral measurements in a peripherally cued line-orientation discrimination task to investigate the underlying mechanisms of orienting and focusing in voluntary and involuntary attention conditions. Informative peripheral cue (75% valid) with long stimulus onset asynchrony (SOA) was used in the voluntary attention condition; uninformative peripheral cue (50% valid) with short SOA was used in the involuntary attention condition. Both orienting and focusing were affected by attention type. Results for attention orienting in the voluntary attention condition confirmed the “sensory gain control theory,” as attention enhanced the amplitude of the early ERP components, P1 and N1, without latency changes. In the involuntary attention condition, compared with invalid trials, targets in the valid trials elicited larger and later contralateral P1 components, and smaller and later contralateral N1 components. Furthermore, but only in the voluntary attention condition, targets in the valid trials elicited larger N2 and P3 components than in the invalid trials. Attention focusing in the involuntary attention condition resulted in larger P1 components elicited by targets in small-cue trials compared to large-cue trials, whereas in the voluntary attention condition, larger P1 components were elicited by targets in large-cue trials than in small-cue trials. There was no interaction between orienting and focusing. These results suggest that orienting and focusing of visual-spatial attention are deployed independently regardless of attention type. In addition, the present results provide evidence of dissociation between voluntary and involuntary attention during the same task.

scholarly journals Reducing Aggression by Developing Emotional and Inhibitory Control

2021 ◽  
Vol 18 (10) ◽  
pp. 5263
Author(s):  
Miriam Romero-López ◽  
María Carmen Pichardo ◽  
Ana Justicia-Arráez ◽  
Judit Bembibre-Serrano
Keyword(s):  
Psychosocial Development ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Generalized Linear Mixed Model ◽  
Emotional Control ◽  
Control Group ◽  
Post Intervention ◽  
Mixed Model Analysis ◽  
Intervention Measures ◽  
Experimental Group

The objective of this study is to measure the effectiveness of a program on improving inhibitory and emotional control among children. In addition, it is assessed whether the improvement of these skills has an effect on the reduction of aggressive behavior in pre-school children. The participants were 100 children, 50 belonging to the control group and 50 to the experimental group, aged between 5 and 6 years. Pre-intervention and post-intervention measures of inhibitory and emotional control (BRIEF-P) and aggression (BASC) were taken. A Generalized Linear Mixed Model analysis (GLMM) was performed and found that children in the experimental group scored higher on inhibitory and emotional control compared to their peers in the control group. In addition, these improvements have an effect on the decrease in aggressiveness. In conclusion, preventive research should have among its priorities the design of such program given their implications for psychosocial development.

scholarly journals PSX-7 Effect of varying levels of hempseed meal supplementation on animal performance, rumen fermentation, and blood metabolites of growing meat goats

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 459-460
Author(s):  
Frank W Abrahamsen ◽  
Nar Gurung ◽  
Woubit Abdela ◽  
Gopal Reddy ◽  
Kim Mullenix
Keyword(s):  
Mixed Model ◽  
Average Daily Gain ◽  
Live Weight ◽  
Blood Chemistry ◽  
Optimal Level ◽  
Rumen Fermentation ◽  
Serum Glucose ◽  
Mixed Model Analysis ◽  
Meat Goats ◽  
Significant Difference

Abstract Hempseed meal (HSM) is a byproduct of hemp oil production and is high in crude protein, fiber, and fat, making it a potential feedstuff for ruminants. The objective of this study was to evaluate the effect of HSM supplementation on growth performance, rumen fermentation and blood chemistry profile of growing meat goats. Forty castrated, Boer cross goats were randomly assigned to one of the four treatments (n = 10): control, 10%, 20%, and 30% HSM supplementation. Data collected over a period of a 60-day feeding trial were analyzed utilizing the mixed model analysis function of SYSTAT, version 13. The result revealed total live weight gain decreased with the increasing levels of HSM supplementation 10.75, 9.53, 8.48, and 7.80 kg, for 0, 10, 20, and 30%, respectively. Average daily gain followed the same trend 0.179, 0.159, 0.141, and 0.13 kg, with a significant difference (P < 0.05) observed between the control and 30 % supplementation. Conversely, feed to gain ratio increased with the increasing levels of supplementation 9.0, 10.2, 11.9, 12.2, likewise a significant difference was observed (P < 0.05) between the control and 30% supplementation. Acetic, propionic, butyric, valeric, iso-valeric, and iso-butyric acid concentrations as well as the total VFA concentration decreased significantly (P < 0.05) with the increasing level of supplementation. Acetic to propionic acid ratios increased with increasing level of supplementation 3.43, 4.36, 4.52, and 4.59, significant differences (P < 0.05) were observed between control-20% and 30% HSM group. Serum glucose concentration decreased with an increasing rate of HSM supplementation while BUN concentration increased with no significant differences. These findings provide new insights into the feeding value of HSM for meat goats; however, further research needs to be conducted to determine the optimal level of supplementation.

scholarly journals Metabolic Adaptations to Dynamic Energy Requirements during Lactation and Pregnancy in Dairy Cows with Varying Proportions of Holstein and Simmental Breed

Proceedings ◽  
2020 ◽  
Vol 73 (1) ◽  
pp. 9
Author(s):  
Deise Aline Knob ◽  
André Thaler Neto ◽  
Helen Schweizer ◽  
Anna Weigand ◽  
Roberto Kappes ◽  
...  
Keyword(s):  
Energy Balance ◽  
Dairy Cows ◽  
Fixed Effects ◽  
Mixed Model ◽  
Negative Energy ◽  
Negative Energy Balance ◽  
Repeated Measure ◽  
Holstein Cows ◽  
Mixed Model Analysis ◽  
Genetic Groups

Depending on the breed or crossbreed line, cows have to cope with a more or less severe negative energy balance during the period of high milk yields in early lactation, which can be detected by beta-hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFAs) in blood. Preventing cows from undergoing a severe negative energy balance by breeding and/or feeding measures is likely to be supported by the public and may help to improve the sustainability of milk production. The aim was to compare BHBA and NEFA concentrations in the blood of Holstein and Simmental cows and their crosses during the prepartum period until the end of lactation. In total, 164 cows formed five genetic groups according to their theoretic proportion of Holstein and Simmental genes as follows: Holstein (100% Holstein; n = 9), R1-Hol (51–99% Holstein; n = 30), F1 crossbreds (50% Holstein, 50% Simmental; n = 17), R1-Sim (1–49% Holstein; n = 81) and Simmental (100% Simmental; n = 27). NEFA and BHBA were evaluated once a week between April 2018 and August 2019. A mixed model analysis with fixed effects breed, week (relative to calving), the interaction of breed and week, parity, calving year, calving season, milking season, and the repeated measure effect on cows was used. Holstein cows had higher NEFAs (0.196 ± 0.013 mmol/L), and Simmental cows had the lowest NEFA concentrations (0.147 ± 0.008 mmol/L, p = 0.03). R1-Sim, F1 and R1-Hol cows had intermediate values (0.166 ± 0.005, 0.165 ± 0.010, 0.162 ± 0.008 mmol/L; respectively). The highest NEFA value was found in the first week after calving (0.49 ± 0.013 mmol/L). BHBA did not differ among genetic groups (p = 0.1007). There was, however, an interaction between the genetic group and week (p = 0.03). While Simmental, R1-Sim and F1 cows had the highest BHBA value, the second week after calving (0.92 ± 0.07 and 1.05 ± 0.04, and 1.10 ± 0.10 mmol/L, respectively), R1-Hol and Holstein cows showed the BHBA peak at the fourth week after calving (1.16 ± 0.07 and 1.36 ± 0.12 mmol/L, respectively). Unexpectedly, Holstein cows had a high BHBA peak again at week 34 after calving (1.68 ± 0.21 mmol/L). The genetic composition of the cows affects NEFA and BHBA. Simmental and R1-Sim cows mobilize fewer body reserves after calving. Therefore, dairy cows with higher degrees of Simmental origin might be more sustainable in comparison with Holstein genetics in the present study.

scholarly journals Methods to Assess Fat Mass in Infants and Young Children: A Comparative Study Using Skinfold Thickness and Air-Displacement Plethysmography

Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 75
Author(s):  
Stefanie M. P. Kouwenhoven ◽  
Nadja Antl ◽  
Jos W. R. Twisk ◽  
Berthold V. Koletzko ◽  
Martijn J. J. Finken ◽  
...  
Keyword(s):  
Young Children ◽  
Fat Mass ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Correlation Coefficients ◽  
Skinfold Thickness ◽  
Limited Information ◽  
Air Displacement Plethysmography ◽  
Mixed Model Analysis ◽  
Infants And Young Children

Background: Traditionally, fat mass is estimated using anthropometric models. Air-displacement plethysmography (ADP) is a relatively new technique for determining fat mass. There is limited information on the agreement between these methods in infants and young children. Therefore we aimed to longitudinally compare fat mass percentage values predicted from skinfold thicknesses (SFTs) and ADP in healthy infants and young children. Methods: Anthropometry and body composition were determined at the ages of 1, 4, and 6 months and 2 years. We quantified the agreement between the two methods using the Bland–Altman procedure, linear mixed-model analysis, and intra-class correlation coefficients (ICC). Results: During the first 6 months of life, fat mass% predicted with SFT was significantly different from that measured with ADP in healthy, term-born infants (n = 245). ICCs ranged from 0.33 (at 2 years of age) and 0.47 (at 4 months of age). Although the mean difference (bias) between the methods was low, the Bland–Altman plots showed proportional differences at all ages with wide limits of agreement. Conclusions: There is poor agreement between ADP and SFTs for estimating fat mass in infancy or early childhood. The amount of body fat was found to influence the agreement between the methods.

scholarly journals Rate and Determinants of Excessive Fat-Free Mass Loss After Bariatric Surgery

2020 ◽  
Vol 30 (8) ◽  
pp. 3119-3126
Author(s):  
Malou A. H. Nuijten ◽  
Valerie M. Monpellier ◽  
Thijs M. H. Eijsvogels ◽  
Ignace M. C. Janssen ◽  
Eric J. Hazebroek ◽  
...  
Keyword(s):  
Bariatric Surgery ◽  
Time Course ◽  
Mixed Model ◽  
Linear Regression Analysis ◽  
Bioelectrical Impedance ◽  
Impedance Analysis ◽  
Fat Free Mass ◽  
Mixed Model Analysis ◽  
Post Surgery ◽  
Post Bariatric Surgery

Abstract Purpose Fat-free mass (FFM) loss is a concerning aspect of bariatric surgery, but little is known about its time-course and factors related with excessive FFM loss. This study examined (i) the progress of FFM loss up to 3 years post-bariatric surgery and (ii) the prevalence and determinants of excessive FFM loss. Materials and Methods A total of 3596 patients (20% males, 43.5 ± 11.1 years old, BMI = 44.2 ± 5.5 kg/m2) underwent sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) surgery. Bioelectrical impedance analysis was performed preoperatively and 3, 6, 9, 12, 18, 24 and 36 months post-surgery. Changes in body composition were assessed by mixed model analysis. Prevalence of excessive FFM loss (based on three different cutoff values: ≥ 25%, ≥ 30% and ≥ 35% FFM loss/weight loss (= %FFML/WL)) was estimated and its determinants were assessed by linear regression analysis. Results Highest rates of FFM loss were found at 3 and 6 months post-surgery, reflecting 57% and 73% of peak FFM loss, respectively. Prevalence of excessive FFM loss ranged from 14 to 46% at 36 months post-surgery, with an older age (β = 0.14, 95%CI = 0.10–0.18, P < .001), being male (β = 3.99, 95%CI = 2.86–5.12, P < .001), higher BMI (β = 0.13, 95%CI = 0.05–0.20, P = .002) and SG (β = 2.56, 95%CI = 1.36–3.76, P < .001) as determinants for a greater %FFML/WL. Conclusion Patients lost most FFM within 3 to 6 months post-surgery. Prevalence of excessive FFM loss was high, emphasizing the need for more vigorous approaches to counteract FFM loss. Furthermore, future studies should assess habitual physical activity and dietary intake shortly after surgery in relation to FFM loss.

scholarly journals Using Brain-Breaks® as a Technology Tool to Increase Attitude towards Physical Activity among Students in Singapore

2021 ◽  
Vol 11 (6) ◽  
pp. 784
Author(s):  
Govindasamy Balasekaran ◽  
Ahmad Arif Bin Ibrahim ◽  
Ng Yew Cheo ◽  
Phua Kia Wang ◽  
Garry Kuan ◽  
...  
Keyword(s):  
Physical Activity ◽  
Mixed Model ◽  
School Curriculum ◽  
Control Group ◽  
School Students ◽  
Mixed Model Analysis ◽  
Before And After ◽  
Brain Breaks ◽  
Student's Attitudes ◽  
The Brain

The purpose of this study was to investigate the effects of classroom-based Brain Breaks® Physical Activity Solution in Southeast Asia Singaporean primary school students and their attitude towards physical activity (PA) over a ten-week intervention. A total of 113 participants (8–11 years old) were randomly assigned to either an experimental (EG) or a control group (CG), with six classes to each group; the Brain Breaks® group (EG: six classes) and the Control group (CG: six classes). All EG members participated in a Brain Breaks® video intervention (three–five min) during academic classes and the CG continued their lessons as per normal. The student’s attitudes towards PA in both research conditions were evaluated using the self–reported Attitudes toward Physical Activity Scale (APAS), applied before and after intervention. The effects of the intervention on APAS scores were analysed using a mixed model analysis of variance with Time as within-subject and Group as between-subject factors. The analysis revealed evidence in support of the positive effect of classroom video interventions such as Brain Breaks® on student’s attitudes toward benefits, importance, learning, self-efficacy, fun, fitness, and trying to do their personal best in PA. The Brain Breaks® intervention provided a positive significant impact on students in Singapore. This study also revealed that interactive technology tools implemented into the school curriculum benefit students in terms of health and education.

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