Inducing oculomotor plasticity to disclose the functional link between voluntary saccades and endogenous attention deployed perifoveally

AbstractTo what extent oculomotor and attention systems are linked remains strongly debated. Previous studies suggested that saccadic adaptation, a well-studied model of oculomotor plasticity, and orienting of attention rely on overlapping networks in the parietal cortex and can functionally interact. Using a Posner-like paradigm in healthy human subjects, we demonstrate for the first time that saccadic adaptation boosts endogenous attention orienting. Indeed, the discrimination of perifoveal targets benefits more from central cues after backward adaptation of leftward voluntary saccades than after a control saccade task. We propose that the overlap of underlying neural networks actually consists of neuronal populations co-activated by oculomotor plasticity and endogenous attention deployed perifoveally. The functional coupling demonstrated here plaids for conceptual models not belonging to the framework of the premotor theory of attention as the latter has been rejected precisely for this voluntary/endogenous modality. These results also open new perspective for rehabilitation of visuo-attentional deficits.

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Functional Coupling of Motor Units Is Modulated During Walking in Human Subjects

Journal of Neurophysiology ◽

10.1152/jn.00844.2002 ◽

2003 ◽

Vol 89 (2) ◽

pp. 960-968 ◽

Cited By ~ 73

Author(s):

D. M. Halliday ◽

B. A. Conway ◽

L.O.D. Christensen ◽

N. L. Hansen ◽

N. P. Petersen ◽

...

Keyword(s):

Motor Unit ◽

Human Subjects ◽

Knee Extensor ◽

Motor Units ◽

Central Peak ◽

Triceps Surae ◽

Human Gait ◽

Functional Coupling ◽

Flexor Muscle ◽

Healthy Human

Time- and frequency-domain analysis of the coupling between pairs of electromyograms (EMG) recorded from leg muscles was investigated during walking in healthy human subjects. For two independent surface EMG signals from the tibialis anterior (TA) muscle, coupling estimated from coherence measurements was observed at frequencies ≤50 Hz, with identifiable peaks occurring in two frequency bands ranging approximately from 8 to 15 and 15 to 20 Hz. The coherence between TA recordings was greatest toward the end of swing, reduced in early swing, and largely absent in midswing. In time-domain estimates constructed from paired TA EMG recordings, a short-lasting central peak indicative of motor-unit synchronization was observed. This feature of motor-unit coupling was also reduced in mid swing. In paired recordings made among triceps surae, quadriceps, and hamstring muscles, a similar pattern of correlation to that for paired TA recordings was observed. However, no significant coupling was observed in recordings for which one EMG recording was made from an ankle flexor/extensor muscle and the other from a knee extensor/flexor muscle. These results demonstrate that for TA a modulation exists in the functional coupling of motor units recruited during swing. The data also indicate that human motoneurons belonging to different muscles are only weakly coupled during walking. This absence of widespread short-term synchronization between the activities of muscles of the leg may provide a basis for the highly adaptive nature of human gait patterns.

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Minimizing Carry-Over Effects After Treatment Failure and Maximizing Therapeutic Outcome

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000180 ◽

2014 ◽

Vol 222 (3) ◽

pp. 171-178 ◽

Cited By ~ 3

Author(s):

Mareile Hofmann ◽

Nathalie Wrobel ◽

Simon Kessner ◽

Ulrike Bingel

Keyword(s):

Treatment Failure ◽

Human Subjects ◽

Subsequent Treatment ◽

Clinical Samples ◽

Administration Route ◽

Healthy Human ◽

Negative Experiences ◽

Analgesic Treatment ◽

Balanced Design ◽

Carry Over

According to experimental and clinical evidence, the experiences of previous treatments are carried over to different therapeutic approaches and impair the outcome of subsequent treatments. In this behavioral pilot study we used a change in administration route to investigate whether the effect of prior treatment experience on a subsequent treatment depends on the similarity of both treatments. We experimentally induced positive or negative experiences with a topical analgesic treatment in two groups of healthy human subjects. Subsequently, we compared responses to a second, unrelated and systemic analgesic treatment between both the positive and negative group. We found that there was no difference in the analgesic response to the second treatment between the two groups. Our data indicate that a change in administration route might reduce the influence of treatment history and therefore be a way to reduce negative carry-over effects after treatment failure. Future studies will have to validate these findings in a fully balanced design including larger, clinical samples.

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Detection of Soluble Fibrin Monomer Complexes in Blood by Means of Protamine Sulphate Test

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651247 ◽

1968 ◽

Vol 20 (01/02) ◽

pp. 044-049 ◽

Cited By ~ 33

Author(s):

B Lipiński ◽

K Worowski

Keyword(s):

Human Subjects ◽

Coronary Thrombosis ◽

Mean Value ◽

Healthy Human ◽

Protamine Sulphate ◽

Soluble Fibrin ◽

Fibrin Monomer ◽

Dog Plasma ◽

The Mean ◽

Precipitable Protein

SummaryIn the present paper described is a simple test for detecting soluble fibrin monomer complexes (SFMC) in blood. The test consists in mixing 1% protamine sulphate with diluted oxalated plasma or serum and reading the optical density at 6190 Å. In experiments with dog plasma, enriched with soluble fibrin complexes, it was shown that OD read in PS test is proportional to the amount of fibrin recovered from the precipitate. It was found that SFMC level in plasma increases in rabbits infused intravenously with thrombin and decreases after injection of plasmin with streptokinase. In both cases PS precipitable protein in serum is elevated indicating enhanced fibrinolysis. In healthy human subjects the mean value of OD readings in plasma and sera were found to be 0.30 and 0.11, while in patients with coronary thrombosis they are 0.64 and 0.05 respectively. The origin of SFMC in circulation under physiological and pathological conditions is discussed.

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Chronic stress decreases circulating endocannabinoid 2-arachidonoylglycerol in healthy human subjects

Endocrine Abstracts ◽

10.1530/endoabs.37.gp.18.01 ◽

2015 ◽

Author(s):

Buqing Yi ◽

Igor Nichiporuk ◽

Matthias Feuerecker ◽

Gustav Schelling ◽

Alexander Chouker

Keyword(s):

Chronic Stress ◽

Human Subjects ◽

Healthy Human ◽

Healthy Human Subjects

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Effect of a Novel Ficus Carica (Fig) Fruit Extract Standardized in Abscisic Acid on the Glycemic and Insulinemic Responses in Healthy Human Subjects

Diabetes ◽

10.2337/db18-791-p ◽

2018 ◽

Vol 67 (Supplement 1) ◽

pp. 791-P

Author(s):

ANDREA ZANGARA

Keyword(s):

Abscisic Acid ◽

Human Subjects ◽

Ficus Carica ◽

Fruit Extract ◽

Healthy Human ◽

Healthy Human Subjects

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Plasma clearance of chylomicrons labeled with retinyl palmitate in healthy human subjects.

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)37744-0 ◽

1984 ◽

Vol 25 (8) ◽

pp. 805-812

Author(s):

F Berr ◽

F Kern

Keyword(s):

Plasma Clearance ◽

Human Subjects ◽

Retinyl Palmitate ◽

Healthy Human ◽

Healthy Human Subjects

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Steady-state kinetics of serum bile acids in healthy human subjects: single and dual isotope techniques using stable isotopes and mass spectrometry.

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)38702-2 ◽

1987 ◽

Vol 28 (3) ◽

pp. 238-252

Author(s):

G T Everson

Keyword(s):

Mass Spectrometry ◽

Stable Isotopes ◽

Steady State ◽

Bile Acids ◽

Human Subjects ◽

Healthy Human ◽

Dual Isotope ◽

Steady State Kinetics ◽

Healthy Human Subjects ◽

Kinetics Of

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Acacia Gum Is Well Tolerated While Increasing Satiety and Lowering Peak Blood Glucose Response in Healthy Human Subjects

Nutrients ◽

10.3390/nu13020618 ◽

2021 ◽

Vol 13 (2) ◽

pp. 618

Author(s):

Riley Larson ◽

Courtney Nelson ◽

Renee Korczak ◽

Holly Willis ◽

Jennifer Erickson ◽

...

Keyword(s):

Blood Glucose ◽

Human Subjects ◽

Area Under The Curve ◽

Soluble Fiber ◽

Healthy Human ◽

Glucose Response ◽

Blood Glucose Response ◽

Acacia Gum ◽

Fiber Treatment ◽

Healthy Human Subjects

Acacia gum (AG) is a non-viscous soluble fiber that is easily incorporated into beverages and foods. To determine its physiological effects in healthy human subjects, we fed 0, 20, and 40 g of acacia gum in orange juice along with a bagel and cream cheese after a 12 h fast and compared satiety, glycemic response, gastrointestinal tolerance, and food intake among treatments. Subjects (n = 48) reported less hunger and greater fullness at 15 min (p = 0.019 and 0.003, respectively) and 240 min (p = 0.036 and 0.05, respectively) after breakfast with the 40 g fiber treatment. They also reported being more satisfied at 15 min (p = 0.011) and less hungry with the 40 g fiber treatment at 30 min (p = 0.012). Subjects reported more bloating, flatulence, and GI rumbling on the 40 g fiber treatment compared to control, although values for GI tolerance were all low with AG treatment. No significant differences were found in area under the curve (AUC) or change from baseline for blood glucose response, although actual blood glucose with 20 g fiber at 30 min was significantly less than control. Individuals varied greatly in their postprandial glucose response to all treatments. AG improves satiety response and may lower peak glucose response at certain timepoints, and it is well tolerated in healthy human subjects. AG can be added to beverages and foods in doses that can help meet fiber recommendations.

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Heart rate variability and baroreflex sensitivity are reduced in chronically undernourished, but otherwise healthy, human subjects

Clinical Science ◽

10.1042/cs1040295 ◽

2003 ◽

Vol 104 (3) ◽

pp. 295-302 ◽

Cited By ~ 4

Author(s):

Mario VAZ ◽

A.V. BHARATHI ◽

S. SUCHARITA ◽

D. NAZARETH

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

High Frequency ◽

Baroreflex Sensitivity ◽

Human Subjects ◽

Normal Weight ◽

Autonomic Nerve ◽

Total Power ◽

Healthy Human ◽

Frequency Power

Alterations in autonomic nerve activity in subjects in a chronically undernourished state have been proposed, but have been inadequately documented. The present study evaluated heart rate and systolic blood pressure variability in the frequency domain in two underweight groups, one of which was undernourished and recruited from the lower socio-economic strata [underweight, undernourished (UW/UN); n = 15], while the other was from a high class of socio-economic background [underweight, well nourished (UW/WN); n = 17], as well as in normal-weight controls [normal weight, well nourished (NW/WN); n = 27]. Baroreflex sensitivity, which is a determinant of heart rate variability, was also assessed. The data indicate that total power (0–0.4Hz), low-frequency power (0.04–0.15Hz) and high-frequency power (0.15–0.4Hz) of RR interval variability were significantly lower in the UW/UN subjects (P<0.05) than in the NW/WN controls when expressed in absolute units, but not when the low- and high-frequency components were normalized for total power. Baroreflex sensitivity was similarly lower in the UW/UN group (P<0.05). Heart rate variability parameters in the UW/WN group were generally between those of the UW/UN and NW/WN groups, but were not statistically different from either. The mechanisms that contribute to the observed differences between undernourished and normal-weight groups, and the implications of these differences, remain to be elucidated.

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