Multiple Saccades Are More Automatic Than Single Saccades

2007 ◽  
Vol 97 (4) ◽  
pp. 3148-3151 ◽  
Author(s):  
Paul van Donkelaar ◽  
Sandy Saavedra ◽  
Marjorie Woollacott
Keyword(s):  
Cerebral Cortex ◽  
Age Groups ◽  
Age Group ◽  
Control Task ◽  
Initial Saccade ◽  
Fixation Control

In this paper, we demonstrate that when a peripheral object is foveated by a sequence of multiple saccades, the initial saccade in the sequence is initiated markedly faster than a single accurate saccade to the same object. We suggest that multiple saccades represent a more automatic form of oculomotor planning that may be the result of a reduced influence from the cerebral cortex. To test this, we compared single and multiple saccade characteristics across development. We find that in contrast to the reduction in the latency of single saccades that is observed across development, the latency of initial saccades in multiple saccade sequences is remarkably stable across all age groups. Moreover, the longer the latency of this initial saccade, the more accurate it is, suggesting that there is a relation between the degree of procrastination and the accuracy of the response. Finally, the frequency with which multiple saccades occurred within each age group was positively correlated with the tendency to generate erroneous saccades during a fixation control task. Taken together, the present data suggest that multiple saccades are generated in a more automatic manner than single saccades.

scholarly journals MULTIMODAL HUMAN BRAIN LONGITUDINAL PARCELLATION ACROSS LIFESPAN

2021 ◽  
Author(s):  
JUNYI YAN ◽  
JINZHU YANG ◽  
DAZHE ZHAO
Keyword(s):  
Cerebral Cortex ◽  
Human Brain ◽  
Clustering Algorithm ◽  
Age Groups ◽  
Population Subdivision ◽  
Connectivity Matrix ◽  
Age Group ◽  
Similarity Matrix ◽  
Human Cerebral Cortex ◽  
Population Average

Subdividing the human brain into several functionally distinct and spatially contiguous areas is important to understand the amazingly complex human cerebral cortex. However, adult aging is related to differences in the structure, function, and connectivity of brain areas, so that the single population subdivision does not apply to multiple age groups. Moreover, different modalities could provide affirmative and complementary information for the human brain subdivision. To obtain a more reasonable subdivision of the cerebral cortex, we make use of multimodal information to subdivide the human cerebral cortex across lifespan. Specifically, we first construct a population average functional connectivity matrix for each modality of each age group. Second, we separately calculate the population average similarity matrix for the cortical thickness and myelin modality of each age group. Finally, we fuse these population average matrixes to obtain the multimodal similarity matrix and feed it into the spectral clustering algorithm to generate the brain parcellation for each age group.

scholarly journals The bioelectric type of the visual area of the cerebral cortex of rats of all ages and sexes

2018 ◽  
Vol 9 (4) ◽  
pp. 514-521
Author(s):  
V. V. Mizin ◽  
V. P. Lyashenko ◽  
S. M. Lukashov
Keyword(s):  
Cerebral Cortex ◽  
Theta Rhythm ◽  
Age Groups ◽  
Young Age ◽  
Visual Area ◽  
Age Group ◽  
Bioelectric Activity ◽  
Absolute Power ◽  
Age Related ◽  
Age Related Changes

In the ontogenesis process, the cerebral cortex undergoes age-related changes. So far as, unlike practically all other systems of mammalian organs, the brain continues to develop and receive new functionality in the postnatal period. Thus with age, there are changes in the bioelectric characteristics of the neocortex. The purpose of the research is to determine the age and sex changes in the bioelectric activity of the cerebral visual cortex of male and female rats of different ages. In the article, we examined changes in absolute (μV2) and normalized (%) indicators of electrical activity of the visual area of rats of different sexes in four age groups: juvenile, young, mature, and presenile age. The research was carried out by the method of registration of bioelectric activity of electrocorticograms (ECoG). Results of multifactorial dispersion analysis of absolute and normalized ECoG indicators of the visual area of the cerebral cortex of rats of all ages showed that there were reliable changes in the frequency-amplitude characteristics of bioelectric activity related to age. At a young age, males have probably lower absolute and normalized power of the delta-rhythm and the normalized beta-like rhythm rate. There was a tendency of decrease in the theta-rhythm. As a result of this redistribution of rhythms a desynchronization of the electrical activity of young males was observed. Mature males have lower absolute power indicators than younger age groups. According to normalized indicators, a synchronization of rhythms of males in the mature age group was observed, which together with values of absolute power can indicate a decrease of the functional activity level of the neocortex and an increase of the influence of endogenous mechanisms on neuronal activity of the visual area of the cerebral cortex. In the presenile age, there was a desynchronization of rhythms. The indicators of an absolute and normalized power of females in the young age group pointed to the synchronization of the bioecoactivity of the neocortex. Among the low-frequency waves, theta-rhythm rhythm dominated in the females of young age. In the mature and presenile age females, there was a probable increase in the percentage of normalized parameters of high-frequency beta waves. The predominance of this rhythm may indicate an increase of cortical tone. The correlation of values of absolute and normalized indicators of bioelectric activity affirmed the desynchronization of the ECoG rhythms of females of mature and presenile age. Sex differences are expressed by a decrease in the absolute power of all ECoG rhythms of the visual area of the cerebral cortex of females relative to males. The age-related changes occurred in a different way in rats of different sex. At a young age, males had desynchronization of rhythms, and females had synchronization, in the mature age it was vice versa. The age changes of the electric activity of the cerebral visual cortex of rats in our opinion may be largely associated with involutional changes of various neurotransmitter and hormonal systems.

The Effect of Collagen Mediated Platelet Release on Plasma Prekallikrein Activation

1984 ◽  
Vol 51 (01) ◽  
pp. 037-041 ◽  
Author(s):  
K M Weerasinghe ◽  
M F Scully ◽  
V V Kakkar
Keyword(s):  
Platelet Aggregation ◽  
Healthy Volunteers ◽  
Platelet Rich Plasma ◽  
Age Groups ◽  
Inhibitory Effect ◽  
Age Group ◽  
Platelet Factor ◽  
Activated Platelets ◽  
Platelet Release ◽  
Collagen Treatment

SummaryCollagen mediated platelet aggregation caused -5.6 ± 6.7% inhibition and +39.1 ± 15.2% potentiation of prekallikrein activation in plasma from normal healthy volunteers between 20–40 and 50–65 years of age, respectively (n = 15, p <0.01). The amouns of platelet factor-four (PF4) released in the two groups were not significantly different. Collagen treatment in the presence of indomethacin caused +11.5 ± 3.6% and +59.6 ± 19.5% potentiation in the 20–40 and 50–65 age groups respectively (p <0.02). Adrenaline mediated platelet aggregation caused -55.2 ± 7.1% and -35.2 ± 8.3% inhibition in the 20–40 and 50–65 age groups, respectively. Collagen treatment of platelet-deficient-plasma and platelet-rich-plasma in EDTA also caused potentiation of prekallikrein activation.The results indicate that the observed degree of prekallikrein activation after platelet aggregation is a net result of the inhibitory effect of PF4 and the potentiatory effect of activated platelets. The potentiatory effect was greater after collagen treatment as compared to adrenaline treatment, and in the 50–65 age group as compared to the 20–40 age group.

Health and Nutritional Status of Orphan Children’s Living in Orphanages with Special Reference to District Anantnag of Jammu and Kashmir

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Mashkoor Ahmad Lone ◽  
Dr. P. Ganesan
Keyword(s):  
Age Groups ◽  
Indian Academy ◽  
Dental Enamel ◽  
Nutritional Intake ◽  
Age Group ◽  
Asian Countries ◽  
Jammu And Kashmir ◽  
Material Resources ◽  
Height For Age ◽  
Weight For Age

The practice of placing deprived children having least or no emotional and material resources, in orphanages has since long been prevailing in socio -economically poor Asian countries. A sample of 30 children residing in orphanage in district Anantnag in the age group of 13-18 years was selected for the present study. Most of the children were found socially and psychologically disturbed. As per Indian Academy Paediatrics (IAP) classification with respect to weight for age the condition was not bad that as approximately 67% percent of the children were found to be normal. In the same way height for age as per Waterloo’s classification shown that more than half of the children were normal. On clinical examination approximately 47% of children were normal, while as rest were suffering from dispigmentation of hair, moon face, xerosis of skin cheilosis, magenta tongue, spongy bleeding gums, oedema, conjuctival xerosis, and mottled dental enamel. The findings indicated that nutritional intake was deficient for all nutrients when compared to, Recommended Daily Allowances Chart (RDA) for all age groups which may be linked to poor planning of menus in orphanages.

COVID-19 Epigenetics and Implications for Public Health

Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Verda Tunalıgil ◽  
Gülsen Meral ◽  
Ahmet Katı ◽  
Dhrubajyoti Chattopadhyay ◽  
Amit Kumar Mandal
Keyword(s):  
Chronic Conditions ◽  
Empirical Investigation ◽  
Age Groups ◽  
Infectious Agent ◽  
Well Being ◽  
Epigenetic Mechanisms ◽  
Age Group ◽  
Epigenetic Changes ◽  
Patient Groups ◽  
Epigenetic Processes

Abstract:: Epigenetic changes in COVID-19 host, a pandemic-causing infectious agent that globally incapacitated communities in varying complexities and capacities are discussed, proposing an analogy that epigenetic processes contribute to disease severity and elevate the risk for death from infection. Percentages of hospitalization, with and without intensive care, in the presence of diseases with increased ACE2 expression, were compared, based on the best available data. Further analysis compared two different age groups, 19-64 and ≥65 years of age. The COVID-19 disease is observed to be the most severe in the 65-and-higher-age group with preexisting chronic conditions. This observational study is a non-experimental empirical investigation of the outcomes of COVID-19 in different patient groups. Results are promising for conducting clinical trials with intervention groups. To ultimately succeed in disease prevention, researchers and clinicians must integrate epigenetic mechanisms to generate valid prescriptions for global well-being.

scholarly journals Tower Running—Participation, Performance Trends, and Sex Difference

2020 ◽  
Vol 17 (6) ◽  
pp. 1902 ◽  
Author(s):  
Daniel Stark ◽  
Stefania Di Gangi ◽  
Caio Victor Sousa ◽  
Pantelis Nikolaidis ◽  
Beat Knechtle
Keyword(s):  
Sex Differences ◽  
Statistical Model ◽  
Sex Difference ◽  
Random Effects ◽  
Age Groups ◽  
Repeated Measurements ◽  
Stair Climbing ◽  
Age Group ◽  
Performance Trends ◽  
The Difference

Though there are exhaustive data about participation, performance trends, and sex differences in performance in different running disciplines and races, no study has analyzed these trends in stair climbing and tower running. The aim of the present study was therefore to investigate these trends in tower running. The data, consisting of 28,203 observations from 24,007 climbers between 2014 and 2019, were analyzed. The effects of sex and age, together with the tower characteristics (i.e., stairs and floors), were examined through a multivariable statistical model with random effects on intercept, at climber’s level, accounting for repeated measurements. Men were faster than women in each age group (p < 0.001 for ages ≤69 years, p = 0.003 for ages > 69 years), and the difference in performance stayed around 0.20 km/h, with a minimum of 0.17 at the oldest age. However, women were able to outperform men in specific situations: (i) in smaller buildings (<600 stairs), for ages between 30 and 59 years and >69 years; (ii) in higher buildings (>2200 stairs), for age groups <20 years and 60–69 years; and (iii) in buildings with 1600–2200 stairs, for ages >69 years. In summary, men were faster than women in this specific running discipline; however, women were able to outperform men in very specific situations (i.e., specific age groups and specific numbers of stairs).

scholarly journals Ten-year trends of hypertension treatment and control rate in Korea

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kwang-il Kim ◽  
Eunjeong Ji ◽  
Jung-yeon Choi ◽  
Sun-wook Kim ◽  
Soyeon Ahn ◽  
...  
Keyword(s):  
Age Groups ◽  
Favorable Effect ◽  
Age Group ◽  
Hypertension Treatment ◽  
Treatment Rate ◽  
Cross Sectional ◽  
The Past ◽  
Nationally Representative ◽  
Multistage Sampling ◽  
And Control

AbstractWe analyzed the Korean National Health and Nutrition Examination Survey (KNHANES) database to determine the trends of hypertension treatment and control rate in Korea over the past 10 years. In addition, we tried to investigate the effect of chronic medical conditions on hypertension management. We investigated the hypertension prevalence, awareness, treatment, and control rate from 2008 to 2017. KNHANES, which uses a stratified multistage sampling design, is a cross-sectional, nationally representative survey conducted by the Korean government. A total of 59,282 adults (≥ 20 years) were included, which was representative of the total population of around 40 million Koreans per year. The mean age was 50.7 ± 16.4 years and 42.6% were male. The prevalence of hypertension, hypercholesterolemia, diabetes mellitus, and obesity significantly increased over the 10 years. During this period, the hypertension treatment and control rate significantly improved. Hypertension treatment rate was significantly lower in the younger age group compared to the older age group, but the control rate among the treated patients was not significantly different between age groups. The treatment and control rates of hypertension were higher in patients with multimorbidity, which implies that it has a favorable effect on the treatment and control of hypertension. Hypertension treatment and control rate have improved over the past 10 years. The higher treatment and control rate in patients with multimorbidity suggest that the more aggressive surveillance might be associated with the improvement of hypertension treatment and control rate in Korea.

scholarly journals A Study of Varicella Seroprevalence in a Pediatric and Adolescent Population in Florence (Italy). Natural Infection and Vaccination-Acquired Immunization

Vaccines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 152
Author(s):  
Beatrice Zanella ◽  
Angela Bechini ◽  
Benedetta Bonito ◽  
Marco Del Riccio ◽  
Alessandra Ninci ◽  
...  
Keyword(s):  
Natural Infection ◽  
Age Groups ◽  
Varicella Vaccination ◽  
Age Group ◽  
Disease Notification ◽  
Test Elisa ◽  
Vaccine Schedule ◽  
Almost All ◽  
Vaccination Campaigns ◽  
Dose Vaccine

Background: Varicella is a well-known infectious disease that can have severe complications, also in young children. The Universal Varicella Vaccination (UVV) program was introduced in Tuscany (Italy) in 2003, with a two-dose vaccine schedule given to children between their 13th and 15th month, and at 5–6 years old, as a monovalent for varicella (V) or tetravalent (measles, mumps, rubella and varicella (MMRV)) formulation. Although varicella notifications have dramatically fallen in the last two decades, varicella disease underreporting remains a challenge. Methods: A qualitative immunoenzymatic test (ELISA) was used to measure the presence of anti-varicella antibodies in 165 sera of subjects aged 1–18 years residing in the province of Florence (Italy). Information regarding the anamnestic and vaccination status (including disease notification) was also collected. Results: Our study showed an overall varicella seropositivity of 75.8% (reaching the maximum at 96.3% in the 15–18 years age group). We found that varicella disease notification had been recorded for only 7/165 subjects; however, since 42/165 recalled having had the disease, we can hypothesize that some of them must have been underreported. Furthermore, our study showed that the presence of antibodies after the varicella vaccination remained over time, lasting up to 12 years. Conclusions: Although varicella seroprevalence is <95% in almost all our age groups (except for the 15–18 years age group), our data are encouraging and reflect the success of the introduction of the UVV program and the vaccination campaigns promoted in the Tuscany region.

scholarly journals One Year of the COVID-19 Pandemic in Galicia: A Global View of Age-Group Statistics during Three Waves

2021 ◽  
Vol 18 (10) ◽  
pp. 5104
Author(s):  
Iván Area ◽  
Henrique Lorenzo ◽  
Pedro J. Marcos ◽  
Juan J. Nieto
Keyword(s):  
Intensive Care Unit ◽  
Hospital Admissions ◽  
Age Groups ◽  
Age Group ◽  
Nw Spain ◽  
The Past ◽  
Global View ◽  
Time Period ◽  
Key Variables ◽  
One Year

In this work we look at the past in order to analyze four key variables after one year of the COVID-19 pandemic in Galicia (NW Spain): new infected, hospital admissions, intensive care unit admissions and deceased. The analysis is presented by age group, comparing at each stage the percentage of the corresponding group with its representation in the society. The time period analyzed covers 1 March 2020 to 1 April 2021, and includes the influence of the B.1.1.7 lineage of COVID-19 which in April 2021 was behind 90% of new cases in Galicia. It is numerically shown how the pandemic affects the age groups 80+, 70+ and 60+, and therefore we give information about how the vaccination process could be scheduled and hints at why the pandemic had different effects in different territories.

scholarly journals Correlation between age, sex, and severity of Coronavirus disease-19 based on chest computed tomography severity scoring system

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Shimaa Farghaly ◽  
Marwa Makboul
Keyword(s):  
Computed Tomography ◽  
Scoring System ◽  
Fatal Outcome ◽  
Age Groups ◽  
Significant Risk ◽  
Chest Ct ◽  
Age Group ◽  
Severity Scoring ◽  
Chest Computed Tomography ◽  
Severity Of The Disease

Abstract Background Coronavirus disease 2019 (COVID-19) is the most recent global health emergency; early diagnosis of COVID-19 is very important for rapid clinical interventions and patient isolation; chest computed tomography (CT) plays an important role in screening, diagnosis, and evaluating the progress of the disease. According to the results of different studies, due to high severity of the disease, clinicians should be aware of the different potential risk factors associated with the fatal outcome, so chest CT severity scoring system was designed for semi-quantitative assessment of the severity of lung disease in COVID-19 patients, ranking the pulmonary involvement on 25 points severity scale according to extent of lung abnormalities; this study aims to evaluate retrospectively the relationship between age and severity of COVID-19 in both sexes based on chest CT severity scoring system. Results Age group C (40–49 year) was the commonest age group that was affected by COVID-19 by 21.3%, while the least affected group was group F (≥ 70 years) by only 6.4%. As regards COVID-RADS classification, COVID-RADS-3 was the most commonly presented at both sexes in all different age groups. Total CT severity lung score had a positive strong significant correlation with the age of the patient (r = 0.64, P < 0.001). Also, a positive strong significant correlation was observed between CT severity lung score and age in both males and females (r = 0.59, P < 0.001) and (r = 0.69, P < 0.001) respectively. Conclusion We concluded that age can be considered as a significant risk factor for the severity of COVID-19 in both sexes. Also, CT can be used as a significant diagnostic tool for the diagnosis of COVID-19 and evaluation of the progression and severity of the disease.

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