scholarly journals Visual plasticity and exercise revisited: no evidence for a “cycling lane”

2018 ◽  
Author(s):  
Abigail E Finn ◽  
Alex S Baldwin ◽  
Alexandre Reynaud ◽  
Robert F Hess
Keyword(s):  
Ocular Dominance ◽  
Monocular Deprivation ◽  
Visual Plasticity ◽  
Deprivation Period ◽  
Deprivation Effect ◽  
Adult Humans ◽  
Before And After ◽  
Exercise Effect ◽  
The Difference ◽  
Enriched Environments

AbstractExperiments using enriched environments have shown that physical exercise modulates visual plasticity in rodents. A recent study (Lunghi & Sale, 2015, doi: 10.1016/j.cub.2015.10.026) investigated whether exercise also affects visual plasticity in adult humans. The plastic effect they measured was the shift in ocular dominance caused by 2 hours of monocular deprivation (e.g. by an eye patch). They used a binocular rivalry task to measure this shift. They found that the magnitude of the shift was increased by exercise during the deprivation period. This effect of exercise was later disputed by a study that used a different behavioural task (Zhouet al., 2017, doi: 10.1155/2017/4780876). Our goal was to determine whether the difference in task was responsible for that study’s failure to find an exercise effect. We set out to replicate Lunghi & Sale (2015). We measured ocular dominance with a rivalry task before and after 2 hours of deprivation. We measured data from two conditions in 30 subjects. On two separate days they either performed exercise or rested during the deprivation period. Contrary to the previous study, we find no significant effect of exercise. We hypothesise that exercise may affect rivalry dynamics in a way that interacts with the measurement of the deprivation effect.

scholarly journals Exercise does not enhance short-term deprivation-induced ocular dominance plasticity: evidence from dichoptic surround suppression

2020 ◽  
Author(s):  
Alex S Baldwin ◽  
Hayden M Green ◽  
Abigail E Finn ◽  
Nicholas Gant ◽  
Robert F Hess
Keyword(s):  
Meta Analysis ◽  
Ocular Dominance ◽  
Relative Strength ◽  
Monocular Deprivation ◽  
Sinusoidal Grating ◽  
Surround Suppression ◽  
Ocular Dominance Plasticity ◽  
Exercise Condition ◽  
Before And After ◽  
The Difference

AbstractThe input from the two eyes is combined in the brain. In this combination, the relative strength of the input from each eye is determined by the ocular dominance. Recent work has shown that this dominance can be temporarily shifted. Covering one eye with an eye patch for a few hours makes its contribution stronger. It has been proposed that this shift can be enhanced by exercise. Here, we test this hypothesis using a dichoptic surround suppression task, and with exercise performed according to American College of Sport Medicine guidelines. We measured detection thresholds for patches of sinusoidal grating shown to one eye. When an annular mask grating was shown simultaneously to the other eye, thresholds were elevated. The difference in the elevation found in each eye is our measure of relative eye dominance. We made these measurements before and after 120 minutes of monocular deprivation (with an eye patch). In the control condition, subjects rested during this time. For the exercise condition, 30 minutes of exercise were performed at the beginning of the patching period. This was followed by 90 minutes of rest. We find that patching results in a shift in ocular dominance that can be measured using dichoptic surround suppression. However, we find no effect of exercise on the magnitude of this shift. We further performed a meta-analysis on the four studies that have examined the effects of exercise on the dominance shift. Looking across these studies, we find no evidence for such an effect.

scholarly journals Brief localised monocular deprivation in adults alters binocular rivalry predominance retinotopically and reduces spatial inhibition

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Shui’er Han ◽  
David Alais ◽  
Hamish MacDougall ◽  
Frans A. J. Verstraten
Keyword(s):  
Young Adults ◽  
Binocular Rivalry ◽  
Ocular Dominance ◽  
Monocular Deprivation ◽  
Annular Region ◽  
Gabaergic Inhibition ◽  
Central Vision ◽  
Short Term ◽  
Deprivation Period ◽  
Deprived Areas

Abstract Short-term deprivation (2.5 h) of an eye has been shown to boost its relative ocular dominance in young adults. Here, we show that a much shorter deprivation period (3–6 min) produces a similar paradoxical boost that is retinotopic and reduces spatial inhibition on neighbouring, non-deprived areas. Partial deprivation was conducted in the left hemifield, central vision or in an annular region, later assessed with a binocular rivalry tracking procedure. Post-deprivation, dominance of the deprived eye increased when rivalling images were within the deprived retinotopic region, but not within neighbouring, non-deprived areas where dominance was dependent on the correspondence between the orientation content of the stimuli presented in the deprived and that of the stimuli presented in non-deprived areas. Together, these results accord with other deprivation studies showing V1 activity changes and reduced GABAergic inhibition.

scholarly journals Can ocular dominance plasticity provide a general index to visual plasticity to personalize treatment in amblyopia?

2020 ◽  
Author(s):  
Chunwen Tao ◽  
Zhifen He ◽  
Yiya Chen ◽  
Jiawei Zhou ◽  
Robert F. Hess
Keyword(s):  
Visual Acuity ◽  
Cortical Plasticity ◽  
Ocular Dominance ◽  
Monocular Deprivation ◽  
Homeostatic Plasticity ◽  
Ocular Dominance Plasticity ◽  
Anisometropic Amblyopia ◽  
Occlusion Therapy ◽  
General Index ◽  
Before And After

AbstractPurposeRecently, Lunghi et al showed that amblyopic eye’s visual acuity per se after 2 months of occlusion therapy could be predicted by a homeostatic plasticity, i.e., the temporary shift of ocular dominance observed after a 2-hour monocular deprivation, in children with anisometropic amblyopia(Lunghi et al., 2016). In this study, we assess whether the visual acuity improvement of the amblyopic eye measured after 2 months of occlusion therapy could be predicted by this plasticity.MethodsSeven children (6.86 ± 1.46 years old; SD) with anisometropic amblyopia participated in this study. All patients were newly diagnosed and had no treatment history before participating in our study. They had finished 2 months of refractive adaptation and then received a 4-hour daily fellow eye patching therapy with an opaque patch for a 2-month period. Best-corrected visual acuity of the amblyopic eye was measured before and after the patching therapy. The homeostatic plasticity was assessed by measuring the temporary shift of ocular dominance observed after 2 hours of occlusion for the amblyopic eye before the treatment started. A binocular phase combination paradigm was used for this test.ResultsWe found that there was no significant correlation between the temporary shift of ocular dominance observed after 2 hours of occlusion for the amblyopic eye before the treatment started and the visual acuity gain obtained by the amblyopic eye from 2-month of classical patching therapy. This result involving the short-term patching of the amblyopic eye is consistent with a reanalysis of Lunghi et al’ s data.ConclusionsOcular dominance plasticity does not provide an index of cortical plasticity in the general sense such that it could be used to predict acuity outcomes from longer term classical patching.

Layer differences in the effect of monocular vision in light- and dark-reared kittens

2001 ◽  
Vol 18 (5) ◽  
pp. 811-820 ◽  
Author(s):  
CHRISTOPHER J. BEAVER ◽  
QINGHUA JI ◽  
NIGEL W. DAW
Keyword(s):  
Visual Cortex ◽  
Critical Period ◽  
Ocular Dominance ◽  
Large Change ◽  
Monocular Deprivation ◽  
Monocular Vision ◽  
Ocular Dominance Plasticity ◽  
The Difference ◽  
Dark Rearing

We compared the effect of 2 days of monocular vision on the ocular dominance of cells in the visual cortex of light-reared kittens with the effect in dark-reared kittens at 6, 9, and 14 weeks of age, and analyzed the results by layer. The size of the ocular-dominance shift declined with age in all layers in light-reared animals. There was not a large change in the ocular-dominance shift with age in dark-reared animals in any layer, suggesting that dark rearing largely keeps the cortex in the immature 6-week state until 14 weeks or longer, although there was a slight decrease in layers II, III, and IV, and a slight increase in layers V and VI. At 14 weeks, the difference between light- and dark-reared animals was smallest in layer IV, larger in layers II/III, and largest in layers V/VI, suggesting that dark rearing has a large effect on intracortical synapses and a small effect on geniculocortical synapses. There was a significant ocular-dominance shift in layer IV at 14 weeks of age in both light- animals and dark-reared animals, showing that the critical period for ocular-dominance plasticity is not ended at this age. While the ocular-dominance shift after 26 h of monocular deprivation in 6-week animals was similar in light- and dark-reared animals, after 14 h it was smaller in dark-reared animals, showing that ocular-dominance changes occur more slowly in dark-reared animals at this age, in agreement with Mower (1991). Increases in selectivity for axis of movement after 26 h of monocular vision were seen in dark-reared animals at 6 weeks of age, but not at 9 or 14 weeks of age, showing that the critical period for axial selectivity ends earlier than the critical period for ocular dominance in dark-reared animals, as it does in light-reared animals.

scholarly journals Sleep Slow Oscillations and Spindles encode ocular dominance plasticity and promote its consolidation in adult humans

2021 ◽  
Author(s):  
Danilo Menicucci ◽  
Claudia Lunghi ◽  
Andrea Zaccaro ◽  
Maria Concetta Morrone ◽  
Angelo Gemignani
Keyword(s):  
Cortical Plasticity ◽  
Ocular Dominance ◽  
Monocular Deprivation ◽  
Homeostatic Plasticity ◽  
Ocular Dominance Plasticity ◽  
Slow Oscillations ◽  
Adult Humans ◽  
The Individual ◽  
Visual Cortical

Sleep and plasticity are highly interrelated, as sleep slow oscillations and sleep spindles are associated with consolidation of Hebbian-based processes. However, in adult humans, visual cortical plasticity is mainly sustained by homeostatic mechanisms, for which the role of sleep is still largely unknown. Here we demonstrate that non-REM sleep stabilizes homeostatic plasticity of ocular dominance in adult humans. We found that the effect of short-term monocular deprivation (boost of the deprived eye) was preserved at the morning awakening (>6 hours after deprivation). Subjects exhibiting stronger consolidation had increased sleep spindle density in frontopolar electrodes, suggesting distributed consolidation processes. Crucially, the individual susceptibility to visual homeostatic plasticity was encoded by changes in sleep slow oscillation rate and shape and spindle power in occipital sites, consistent with an early visual cortical site of ocular dominance homeostatic plasticity.

Tem analysis of multiple-energy arsenic implanted and Rta'd silicon

1987 ◽  
Vol 45 ◽  
pp. 246-247
Author(s):  
R.A. Herring
Keyword(s):  
Device Fabrication ◽  
High Concentration ◽  
Tem Analysis ◽  
Defect Clusters ◽  
High Fluences ◽  
Small Defect ◽  
Before And After ◽  
The Matrix ◽  
The Difference ◽  
Factor Type

Rapid thermal annealing (RTA) of ion-implanted Si is important for device fabrication. The defect structures of 2.5, 4.0, and 6.0 MeV As-implanted silicon irradiated to fluences of 2E14, 4E14, and 6E14, respectively, have been analyzed by electron diffraction both before and after RTA at 1100°C for 10 seconds. At such high fluences and energies the implanted As ions change the Si from crystalline to amorphous. Three distinct amorphous regions emerge due to the three implantation energies used (Fig. 1). The amorphous regions are separated from each other by crystalline Si (marked L1, L2, and L3 in Fig. 1) which contains a high concentration of small defect clusters. The small defect clusters were similar to what had been determined earlier as being amorphous zones since their contrast was principally of the structure-factor type that arises due to the difference in extinction distance between the matrix and damage regions.

Changes in Platelet Aggregability after Ovariectomy

1979 ◽  
Vol 42 (04) ◽  
pp. 1332-1339 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Takeshi Motomiya ◽  
Minoru Sonoda ◽  
Noboru Miyagawa
Keyword(s):  
Platelet Count ◽  
Platelet Activation ◽  
Ovarian Hormones ◽  
Control Group ◽  
Platelet Aggregability ◽  
Appearance Rate ◽  
Before And After ◽  
The Difference ◽  
Induced Aggregation ◽  
Observation Period

SummaryChanges in platelets in 48 patients with uterine myoma before and after hysterectomy with and without ovariectomy were examined. Bilateral ovariectomy in 25 cases (ovariec-tomized group) and unilateral or non-ovariectomy in 23 cases (control group) were performed at the hysterectomy. Platelet count and an appearance rate of secondary aggregation decreased at one day after and increased at one week after the operation, similarly in both the ovariectomized and the control group. The appearance rate of secondary aggregation was reflected in an intensity of aggregation at 5 min after the addition of reagent to PRP. At one month after the operation, the appearance rate of secondary aggregation induced by 3 μM ADP showed a statistically significant decrease in comparison with the preoperation value (P <0.05) and the enhancement of 5-min aggregation was still observed in the control group, while ceased in the ovariectomized group. The difference between the two groups was significant (P < 0.05). There was almost no change in the speed and intensity of primary and secondary aggregation during the observation period. No significant differences in collagen-induced aggregation were noted between the two groups. The results suggest that ovarian hormones, mainly estrogen, facilitate platelet activation which is mediated by the so-called secondary aggregation.

PENGARUH TERAPI TERTAWA TERHADAP PENURUNAN TEKANAN DARAH LANSIA DI UPT PANTI WREDHA BUDHI DHARMA YOGYAKARTA

2019 ◽  
Vol 13 (1) ◽  
Author(s):  
Niken Setyaningrum ◽  
Andri Setyorini ◽  
Fachruddin Tri Fitrianta
Keyword(s):  
Blood Pressure ◽  
Data Analysis ◽  
The Elderly ◽  
Control Group ◽  
Group Comparison ◽  
Control Blood Pressure ◽  
Men And Women ◽  
Treatment Of Hypertension ◽  
Before And After ◽  
The Difference

ABSTRACTBackground: Hypertension is one of the most common diseases, because this disease is suffered byboth men and women, as well as adults and young people. Treatment of hypertension does not onlyrely on medications from the doctor or regulate diet alone, but it is also important to make our bodyalways relaxed. Laughter can help to control blood pressure by reducing endocrine stress andcreating a relaxed condition to deal with relaxation.Objective: The general objective of the study was to determine the effect of laughter therapy ondecreasing elderly blood pressure in UPT Panti Wredha Budhi Dharma Yogyakarta.Methods: The design used in this study is a pre-experimental design study with one group pre-posttestresearch design where there is no control group (comparison). The population in this study wereelderly aged over> 60 years at 55 UPT Panti Wredha Budhi Dharma Yogyakarta. The method oftaking in this study uses total sampling. The sample in this study were 55 elderly. Data analysis wasused to determine the difference in blood pressure before and after laughing therapy with a ratio datascale that was using Pairs T-TestResult: There is an effect of laughing therapy on blood pressure in the elderly at UPT Panti WredhaBudhi Dharma Yogyakarta marked with a significant value of 0.000 (P <0.05)

Klein with Lacan: A Study on the Reception of Lacanian Ideas in Uruguay and Its Effects on Clinical Practices (1955–82)

2020 ◽  
Vol 22 (3) ◽  
pp. 341-361
Author(s):  
Gonzalo Grau-Pérez ◽  
J. Guillermo Milán
Keyword(s):  
Clinical Practice ◽  
Clinical Material ◽  
Clinical Practices ◽  
Before And After ◽  
The Difference ◽  
The 1960S ◽  
The Relationship ◽  
Discursive Approach ◽  
The Way ◽  
Clinical Cases

In Uruguay, Lacanian ideas arrived in the 1960s, into a context of Kleinian hegemony. Adopting a discursive approach, this study researched the initial reception of these ideas and its effects on clinical practices. We gathered a corpus of discursive data from clinical cases and theoretical-doctrinal articles (from the 1960s, 1970s and 1980s). In order to examine the effects of Lacanian ideas, we analysed the difference in the way of interpreting the clinical material before and after Lacan's reception. The results of this research illuminate some epistemological problems of psychoanalysis, especially the relationship between theory and clinical practice.

FRACTIONAL DETERMINATIONS OF URINARY 17-KETOSTEROIDS IN HYPEREMESIS GRAVIDARUM

1962 ◽  
Vol 41 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Pentti A. Järvinen ◽  
Sykkö Pesonen ◽  
Pirkko Väänänen
Keyword(s):  
Hyperemesis Gravidarum ◽  
First Trimester ◽  
Control Group ◽  
Before And After ◽  
Daily Urine ◽  
First Trimester Of Pregnancy ◽  
The Difference

ABSTRACT The fractional determination of 17-ketosteroids in the daily urine was performed in nine cases of hyperemesis gravidarum and in four control cases, in the first trimester of pregnancy both before and after corticotrophin administration. The excretion of total 17-KS is similar in the two groups. Only in the hyperemesis group does the excretion of total 17-KS increase significantly after corticotrophin administration. The fractional determination reveals no difference between the two groups of patients with regard to the values of the fractions U (unidentified 17-KS), A (androsterone) and Rest (11-oxygenated 17-KS). The excretion of dehydroepiandrosterone is significantly higher in the hyperemesis group than in the control group. The excretion of androstanolone seems to be lower in the hyperemesis group than in the control group, but the difference is not statistically significant. The differences in the correlation between dehydroepiandrosterone and androstanolone in the two groups is significant. The high excretion of dehydroepiandrosterone and low excretion of androstanolone in cases of hyperemesis gravidarum is a sign of adrenal dysfunction.

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