scholarly journals Spatial and Temporal Asymmetries in Gait Predict Split-Belt Adaptation Behavior in Stroke

2013 ◽  
Vol 28 (3) ◽  
pp. 230-240 ◽  
Author(s):  
Laura A. Malone ◽  
Amy J. Bastian
Keyword(s):  
Training Session ◽  
Speed Ratio ◽  
Stroke Patients ◽  
Healthy Older Adults ◽  
After Effects ◽  
Spatial Domains ◽  
After Effect ◽  
Spatial Asymmetries ◽  
Temporal Measures ◽  
Measures Of Asymmetry

Background. Step asymmetries during gait in persons after stroke can occur in temporal or spatial domains. Prior studies have shown that split-belt locomotor adaptation can temporarily mitigate these asymmetries. Objective. We investigated whether baseline gait asymmetries affected how patients adapt and store new walking patterns. Methods. Subjects with stroke and age-matched controls were studied walking at a 2:1 speed ratio on the split-belt during adaptation and assessed for retention of the learned pattern (the after-effect) with both belts at the same speed. Results. Those with stroke adapted more slowly ( P < .0001), though just as much as healthy older adults. During split-belt walking, the participants with stroke adapted toward their baseline asymmetry (eg, F = 14.02, P < .01 for step symmetry), regardless of whether the subsequent after-effects improved or worsened their baseline step asymmetries. No correlation was found between baseline spatial and temporal measures of asymmetry ( P = .38). Last, the initial spatial and temporal asymmetries predicted after-effects independently of one another. The after-effects in the spatial domain (ie, center of oscillation difference) are only predicted by center of oscillation difference baseline ( F = 15.3, P = .001), while all other parameters were nonsignificant (all Ps > .17). Temporal coordination (ie, phasing) after-effects showed a significant effect only from phasing baseline ( F = 26.92, P < .001, all others P > .33). Conclusion. This work demonstrates that stroke patients adapt toward their baseline temporal and spatial asymmetries of walking independently of one another. We define how a given split-belt training session would affect asymmetries in these domains, which must be considered when developing rehabilitation interventions for stroke patients.

Co-ordination of Successive Activities in an Aphid. Depression of Settling after Flight

1964 ◽  
Vol 41 (4) ◽  
pp. 805-824
Author(s):  
J. S. KENNEDY ◽  
C. O. BOOTH
Keyword(s):  
Priming Effect ◽  
Depressing Effect ◽  
After Effects ◽  
After Effect

1. Flight has a cumulative ‘priming’ effect (excitatory after-effect) on the settling responses of an aphid landing on a surface, even when the flight has been interrupted by one or more previous landings. But when the bouts of flying between landings were kept brief (1 min.) there was also an opposite, depressing or inhibitory after-effect on settling which reduced and in certain conditions regularly outweighed the priming effect. 2. Which of the two after-effects predominated depended on the kind of surface landed on each time, on the strength of the settling responses at previous landings and on the total time the aphid had been flying. 3. The depressing effect as measured on a standard host leaf was negligible when the flight had been interrupted by landings on a card, where the settling responses were weakest and soonest inhibited by flight again, greater after landings on a non-host leaf and greatest after landings on the host leaf, itself where settling responses were strongest. 4. When two successive landings were both made on the same surface, a depression of settling at the second landing was more likely after a strong previous settling response than after a weak one; it was also more likely when the two landings were made on a non-host than when they were made on a host. 5. Flight and settling are nervous antagonists and the terms ‘antagonistic induction’ and ‘antagonistic depression’ are applied, respectively, to the excitatory and the inhibitory after-effects of flight on settling. These are components in the co-ordination of flight and settling as successive activities and do not necessarily describe the sequences observed.

scholarly journals Dry matter production and nitrogen utilization in cropping systems with grass, lucerne and maize. 2. Nitrogen yield and utilization.

1986 ◽  
Vol 34 (1) ◽  
pp. 37-47
Author(s):  
J.H.J. Spiertz ◽  
L. Sibma
Keyword(s):  
Cropping Systems ◽  
Mineral Soil ◽  
Weather Conditions ◽  
N Fertilization ◽  
N Fixation ◽  
Maize Crop ◽  
After Effects ◽  
Matter Production ◽  
After Effect ◽  
Use Efficiency

The N yield and the N use efficiency were studied in a 3-year experiment with various cropping systems of Lolium perenne, Medicago sativa and maize. N yields of L. perenne and maize were about 450 and 200 kg/ha, resp. N yields of M. sativa ranged from about 400 to 600 kg/ha depending on crop age and weather conditions. N fixation rates of M. sativa were assessed in 1982 and ranged from 107 to 507 kg/ha for high (450 kg N/ha) and no N fertilization, resp. The after-effects of 1-, 2- and 3-year crops of L. perenne, M. sativa and maize on the DM and N yields of a test crop of maize were measured. Depending on the age of the preceding L. perenne crop, annually supplied with 450 kg N/ha, the N after-effects ranged from 120 to 175 kg/ha. The after-effect of a previous cropping with M. sativa was independent of the N dressing and ranged from 140 to 175 kg/ha. For comparison, the after-effect of a preceding maize crop ranged from 90 to 110 kg/ha. Mineral soil N reserves were determined in spring and autumn. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Multiple Orientation-Contingent Chromatic After-Effects

1977 ◽  
Vol 29 (2) ◽  
pp. 203-218 ◽  
Author(s):  
Valerie Mackay ◽  
Donald M. Mackay
Keyword(s):  
Angular Distribution ◽  
Orthogonal Test ◽  
After Effects ◽  
Test Grating ◽  
Neural Representations ◽  
Minimum Angle ◽  
After Effect ◽  
Opponent Processing ◽  
Time Courses

McCollough's (1965) original demonstration of an orientation-contingent chromatic after-effect (OCCA) used two orthogonal inducing gratings in complementary colours. Fidell (1970) has shown that inducing gratings whose orientations are separated by less than 90° give progressively smaller OCCAs, becoming ineffective below 20° or so. Stromeyer (1969) found that with only a single inducing grating, orthogonal test fields still appeared tinted in complementary hues, and claimed that these hues could be “neutralized” by rotating the inducing grating by 90°. These results raise the question whether (A) the neural representations of orthogonal orientations are coupled with respect to colour in “opponent” fashion, so that red-horizontal has similar effects to green-vertical; or (B) the representations of orientations separated by some minimum angle are chromatically independent, and can develop substantially independent OCCAs. We report the following results which favour hypothesis (B): (1) With a single coloured inducing grating à la Stromeyer (1969), the measured OCCA at right angles shows no signs of “opponent processing”, if the hue of the test grating is compared against that of a plain field rather than an orthogonal grating. (2) With inducing gratings at several orientations, the resultant OCCA has an angular distribution which is the algebraic sum of those for each grating separately. (3) It is possible to associate the same colour with two orientations at right angles without mutual cancellation. (4) Multiple OCCAs show independent time-courses of decay, and can be induced and retained for at least eight orientations at once.

scholarly journals Human perception of shape from touch

2011 ◽  
Vol 366 (1581) ◽  
pp. 3106-3114 ◽  
Author(s):  
Astrid M. L. Kappers
Keyword(s):  
Human Perception ◽  
The Other ◽  
Dominant Factor ◽  
Stimulus Information ◽  
After Effects ◽  
First Order ◽  
Other Hand ◽  
After Effect ◽  
The Difference

In this paper, I focus on the role of active touch in three aspects of shape perception and discrimination studies. First an overview is given of curvature discrimination experiments. The most prominent result is that first-order stimulus information (that is, the difference in attitude or slope over the stimulus) is the dominant factor determining the curvature threshold. Secondly, I compare touch under bimanual and two-finger performance with unimanual and one-finger performance. Consistently, bimanual or two-finger performance turned out to be worse. The most likely explanation for the former finding is that a loss of accuracy during intermanual comparisons is owing to interhemispheric relay. Thirdly, I address the presence of strong after-effects after just briefly touching a shape. These after-effects have been measured and studied in various conditions (such as, static, dynamic, transfer to other hand or finger). Combination of the results of these studies leads to the insight that there are possibly different classes of after-effect: a strong after-effect, caused by immediate contact with the stimulus, that does only partially transfer to the other hand, and one much less strong after-effect, caused by moving over the stimulus for a certain period, which shows a full transfer to other fingers.

scholarly journals Contributions of spatial and temporal control of step length symmetry in the transfer of locomotor adaptation from a motorized to a non-motorized split-belt treadmill

2019 ◽  
Author(s):  
Daniel L. Gregory ◽  
Frank C. Sup ◽  
Julia T. Choi
Keyword(s):  
Repeated Measures ◽  
Step Length ◽  
Treadmill Walking ◽  
The Body ◽  
Speed Ratio ◽  
Temporal Control ◽  
After Effects ◽  
Locomotor Adaptation ◽  
Length Difference ◽  
Motor Outputs

AbstractBackgroundLocomotor adaptation during motorized split-belt walking depends on independent processes for spatial and temporal control of step length symmetry. The unique mechanics of motorized split-belt walking that constrains two limbs to move at different speeds during double support may limit transfer of step length adaptations to new walking contexts.Research questionHow do spatial and temporal locomotor outputs contribute to transfer of step length adaptation from constrained motorized split-belt walking to unconstrained non-motorized split-belt walking?MethodsWe built a non-motorized split-belt treadmill that allows the user to walk at their own pace while simultaneously allowing the two belts to be self-propelled at different speeds. 10 healthy young participants walked on the non-motorized split-belt treadmill after an initial 10-minute adaptation on the motorized split-belt with a 2:1 speed ratio. Foot placement relative to the body and timing between heel strikes were calculated to determine spatial and temporal motor outputs, respectively. Separate repeated measures ANOVAs were used for step length difference and its spatial and temporal components to assess for transfer to the non-motorized treadmill.ResultsWe found robust after-effects in step length difference during transfer to non-motorized split-belt treadmill walking that were primarily driven by changes in temporal motor outputs. Conversely, residual after-effects observed during motorized tied-belt treadmill walking (post-transfer) were driven by changes in spatial motor outputs.SignificanceOur data showed decoupling of adapted spatial and temporal locomotor outputs during the transfer to non-motorized split-belt walking, raising the new possibility of using a non-motorized split-belt treadmill to target specific spatial or temporal gait deficits.

scholarly journals PENGEMBANGAN FILM DOKUMENTER TRADISI DEWA MESRAMAN DI PURA PANTI TIMRAH KLUNGKUNG

2017 ◽  
Vol 6 (1) ◽  
pp. 159
Author(s):  
I Gede Herri Yudiana Sucitra . ◽  
I Gede Mahendra Darmawiguna, S.Kom, M.Sc . ◽  
Gede Aditra Pradnyana, S.Kom., M.Kom .
Keyword(s):  
Public Perception ◽  
Phase 1 ◽  
Video Editing ◽  
Phase 3 ◽  
After Effects ◽  
The Public ◽  
The People ◽  
After Effect ◽  
The Village ◽  
Adobe Premiere

Tradisi Dewa Mesraman merupakan salah satu tradisi yang tergolong upacara Dewa Yadnya yang terdapat di Kecamatan Dawan, Desa Paksabali, Banjar Timrah tepatnya berada di Pura Panti Timrah. Film Dokumenter Dewa Mesraman ini bertujuan untuk : (1) mengimplementasikan Pengembangan Film Dokumenter Tradisi Dewa Mesraman Di Pura Panti Timrah Klungkung (2) meluruskan persepsi masyarakat terhadap makna dari tradisi Dewa Mesraman. Metode penelitian yang digunakan adalah cyclic strategy atau strategi berputar, cyclic strategy merupakan sebuah metode yang ada kalanya suatu tahap perlu diulang kembali sebelum tahap berikutnya dilanjutkan. Pengulangan tahap ini sering disebut dengan loop. Adapun tahap – tahap dari cyclic stragey diantaranya adalah Brief, Tahap 1, Tahap 2, evaluasi 1, Tahap 3, Evaluasi 2, Tahap 4, Outcome. Pengembangan film ini diimplementasikan menggunakan Adobe Premiere Pro Cs6 sebagai software editing video beserta bantuan Adobe After Effect sebagai penambah efek pada video. Dengan dibuatnya film dokumenter “Tradisi Dewa Mesraman”, masyarakat diharapkan bisa lebih mengetahui dan mengenal segala kearifan lokal yang ada di Desa Paksebali Klungkung, sehingga film dokumenter ini dapat dijadikan sebagai media informasi serta menjadi inspirasi bagi masyarakat Kabupaten Klungkung dan masyarakat luas pada umumnya.Kata Kunci : Dewa Mesraman, Pura Panti Timrah, Film Dokumenter, Tradisi. Dewa Mesraman tradition is one of the traditions that belong to Deity ceremony Yadnya contained in Dawan sub district, village Paksabali, Banjar Timrah precisely located in Panti Pura Timrah. Documentary Mesraman Dewa aims to: (1) implement the Development of Documentary Tradition Dewa Mesraman In Pura Panti Timrah Klungkung (2) align public perception of the significance of tradition Mesraman god. The method used is the cyclic strategy or strategies revolve, cyclic strategy is a method that is sometimes a necessary step before the next step was repeated followed. The repetition of this phase is often called the loop. As for the stage - the stage of cyclic stragey include Brief, Phase 1, Phase 2, the evaluation 1, Phase 3, Evaluation 2, Phase 4, Outcome. Development of the film is implemented using Adobe Premiere Pro CS6 as video editing software along with the help of Adobe After Effects as an addition to the effect on the video. With the making of the documentary film "Gods Mesraman Tradition", the public is expected to be more aware of and familiar with all the local knowledge that exists in the village Paksebali Klungkung, so this documentary can be used as a medium of information as well as an inspiration for the people of Klungkung and the public at large. keyword : Dewa Mesraman, Pura Panti Timrah, Documentary, Tradition.

scholarly journals Effects of targeted assistance and perturbations on the relationship between pelvis motion and step width in people with chronic stroke

2020 ◽  
Author(s):  
Nicholas K. Reimold ◽  
Holly A. Knapp ◽  
Alyssa N. Chesnutt ◽  
Alexa Agne ◽  
Jesse C. Dean
Keyword(s):  
Force Field ◽  
Chronic Stroke ◽  
Step Width ◽  
Foot Placement ◽  
After Effects ◽  
Minute Period ◽  
After Effect ◽  
Targeted Assistance ◽  
Future Work ◽  
The Relationship

AbstractBackgroundPeople with chronic stroke (PwCS) often exhibit a weakened relationship between pelvis motion and paretic step width, a behavior important for gait stabilization. We have developed a force-field able to manipulate this relationship on a step-by-step basis.ObjectiveThe objective of this study was to investigate the effects of a single exposure to our novel force-field on the step-by-step modulation of paretic step width among PwCS, quantified by the partial correlation between mediolateral pelvis displacement at the start of a step and paretic step width (step start paretic ρdisp).MethodsFollowing a 3-minute period of normal walking, participants were exposed to 5-minutes of either force-field assistance (n=10; pushing the swing leg toward a mechanically-appropriate step width) or perturbations (n=10; pushing the swing leg away from a mechanically-appropriate step width). This period of assistance or perturbations was followed by a 1-minute catch period to identify any after-effects, a sign of sensorimotor adaptation.ResultsWe found that assistance did not have a significant direct effect or after-effect on step start paretic ρdisp. In contrast, perturbations directly reduced step start paretic ρdisp (p=0.004), but were followed by an after-effect in which this metric was increased above the baseline level (p=0.02).ConclusionsThese initial results suggest that PwCS have the ability to strengthen the link between pelvis motion and paretic foot placement if exposed to a novel mechanical environment, which may benefit gait stability. Future work is needed to determine whether this effect can be extended with repeated exposure to force-field perturbations.

scholarly journals Effects of a single mental chronometry training session in subacute stroke patients – a randomized controlled trial

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Joachim Liepert ◽  
Jana Stürner ◽  
Imke Büsching ◽  
Aida Sehle ◽  
Mircea A. Schoenfeld
Keyword(s):  
Motor Imagery ◽  
Training Session ◽  
Silent Period ◽  
Motor Execution ◽  
Stroke Patients ◽  
Identification Task ◽  
Sensory Deficits ◽  
Subacute Stroke ◽  
Mental Chronometry ◽  
Motor Excitability

Abstract Background Motor imagery training might be helpful in stroke rehabilitation. This study explored if a single session of motor imagery (MI) training induces performance changes in mental chronometry (MC), motor execution, or changes of motor excitability. Methods Subacute stroke patients (n = 33) participated in two training sessions. The order was randomized. One training consisted of a mental chronometry task, the other training was a hand identification task, each lasting 30 min. Before and after the training session, the Box and Block Test (BBT) was fully executed and also performed as a mental version which served as a measure of MC. A subgroup analysis based on the presence of sensory deficits was performed. Patients were allocated to three groups (no sensory deficits, moderate sensory deficits, severe sensory deficits). Motor excitability was measured by transcranial magnetic stimulation (TMS) pre and post training. Amplitudes of motor evoked potentials at rest and during pre-innervation as well as the duration of cortical silent period were measured in the affected and the non-affected hand. Results Pre-post differences of MC showed an improved MC after the MI training, whereas MC was worse after the hand identification training. Motor execution of the BBT was significantly improved after mental chronometry training but not after hand identification task training. Patients with severe sensory deficits performed significantly inferior in BBT execution and MC abilities prior to the training session compared to patients without sensory deficits or with moderate sensory deficits. However, pre-post differences of MC were similar in the 3 groups. TMS results were not different between pre and post training but showed significant differences between affected and unaffected side. Conclusion Even a single training session can modulate MC abilities and BBT motor execution in a task-specific way. Severe sensory deficits are associated with poorer motor performance and poorer MC ability, but do not have a negative impact on training-associated changes of mental chronometry. Studies with longer treatment periods should explore if the observed changes can further be expanded. Trial registration DRKS, DRKS00020355, registered March 9th, 2020, retrospectively registered

scholarly journals CPC-049 Evaluation of a Standardised Therapeutic Education Training Session For Hypertensive Stroke Patients

2013 ◽  
Vol 20 (Suppl 1) ◽  
pp. A183.1-A183
Author(s):  
C Vallet ◽  
H Beaussier ◽  
M Bruandet ◽  
M Zuber ◽  
Y Bezie ◽  
...  
Keyword(s):  
Training Session ◽  
Therapeutic Education ◽  
Stroke Patients ◽  
Education Training
Sign in / Sign up

Export Citation Format

Share Document