Size–Weight Illusion, Anticipation, and Adaptation of Fingertip Forces in Patients With Cerebellar Degeneration

2009 ◽  
Vol 101 (2) ◽  
pp. 569-579 ◽  
Author(s):  
K. Rabe ◽  
B. Brandauer ◽  
Y. Li ◽  
E. R. Gizewski ◽  
D. Timmann ◽  
...  
Keyword(s):  
Cerebellar Degeneration ◽  
Load Force ◽  
Control Group ◽  
Equal Weight ◽  
Small Object ◽  
Large Object ◽  
Object Weight ◽  
And Gender ◽  
Weight Illusion ◽  
Fingertip Forces

The smaller of two equally weighted objects is judged to be heavier when lifted (size–weight illusion [SWI]). In contrast, fingertip forces show an initial size effect but adapt to the true object weights within a few trials. The aim of this study was to investigate possible contributions of the cerebellum to SWI, force anticipation, and adaptation based on object size and weight. Eighteen participants with isolated cerebellar degeneration and 18 age- and gender-matched controls alternately lifted objects of equal weight but different size in 40 trials. All participants perceived the small object to be heavier after lifting (perceptive SWI). Fingertip forces were significantly higher during the first lift of the large object compared with the small object in the control and cerebellar groups. For the load-force rate and lifting acceleration, effects of anticipation were significantly less in the cerebellar compared with the control group. Grip and load forces were adapted to object weight during repeated lifts in both groups. Preserved perceptive SWI in cerebellar patients supports the hypothesis that perceptive SWI depends on the function of the ventral visual path that receives no or few efferents from the cerebellum. The findings of preserved anticipation and adaptation of grip forces in cerebellar patients, however, were unexpected. Reduced anticipation of load forces suggests that the neural presentation of predictive grip- and load-force control may be different. Findings show that representation and adaptation of internal models of object characteristics are not exclusively located in the cerebellum.

Demonstrations of the Size-Weight Illusion

1997 ◽  
Vol 24 (3) ◽  
pp. 195-197 ◽  
Author(s):  
David T. Homer ◽  
K. Desix Robinson
Keyword(s):  
Equal Weight ◽  
Small Object ◽  
Haptic Information ◽  
Large Object ◽  
Weight Illusion

The size-weight illusion occurs when a person lifts 2 equal-weight objects differing in size and perceives the large object as lighter than the small object. Varying the availability of visual and haptic information influences the strength of the illusion. This article describes several inexpensive techniques for demonstrating the size-weight illusion and some relevant issues concerning the illusion.

scholarly journals Quantifying feedforward control: a linear scaling model for fingertip forces and object weight

2015 ◽  
Vol 114 (1) ◽  
pp. 411-418 ◽  
Author(s):  
Ying Lu ◽  
Seda Bilaloglu ◽  
Viswanath Aluru ◽  
Preeti Raghavan
Keyword(s):  
Feedforward Control ◽  
Peak Load ◽  
Rate Of Change ◽  
Load Force ◽  
Healthy Individuals ◽  
Object Weight ◽  
Custom Made ◽  
Precise Relationship ◽  
Log Linear ◽  
Fingertip Forces

The ability to predict the optimal fingertip forces according to object properties before the object is lifted is known as feedforward control, and it is thought to occur due to the formation of internal representations of the object's properties. The control of fingertip forces to objects of different weights has been studied extensively by using a custom-made grip device instrumented with force sensors. Feedforward control is measured by the rate of change of the vertical (load) force before the object is lifted. However, the precise relationship between the rate of change of load force and object weight and how it varies across healthy individuals in a population is not clearly understood. Using sets of 10 different weights, we have shown that there is a log-linear relationship between the fingertip load force rates and weight among neurologically intact individuals. We found that after one practice lift, as the weight increased, the peak load force rate (PLFR) increased by a fixed percentage, and this proportionality was common among the healthy subjects. However, at any given weight, the level of PLFR varied across individuals and was related to the efficiency of the muscles involved in lifting the object, in this case the wrist and finger extensor muscles. These results quantify feedforward control during grasp and lift among healthy individuals and provide new benchmarks to interpret data from neurologically impaired populations as well as a means to assess the effect of interventions on restoration of feedforward control and its relationship to muscular control.

Material evidence: interaction of well-learned priors and sensorimotor memory when lifting objects

2012 ◽  
Vol 108 (5) ◽  
pp. 1262-1269 ◽  
Author(s):  
Lee A. Baugh ◽  
Michelle Kao ◽  
Roland S. Johansson ◽  
J. Randall Flanagan
Keyword(s):  
Rate Of Change ◽  
Core Material ◽  
Load Force ◽  
Small Object ◽  
Surface Material ◽  
Phase Duration ◽  
Material Density ◽  
Small Cube ◽  
Object Weight ◽  
Sensorimotor Memory

Skilled object lifting requires the prediction of object weight. When lifting new objects, such prediction is based on well-learned size-weight and material-density correlations, or priors. However, if the prediction is erroneous, people quickly learn the weight of the particular object and can use this knowledge, referred to as sensorimotor memory, when lifting the object again. In the present study, we explored how sensorimotor memory, gained when lifting a given object, interacts with well-learned material-density priors when predicting the weight of a larger but otherwise similar-looking object. Different groups of participants 1st lifted 1 of 4 small objects 10 times. These included a pair of wood-filled objects and a pair of brass-filled objects where 1 of each pair was covered in a wood veneer and the other was covered in a brass veneer. All groups then lifted a larger, brass-filled object with the same covering as the small object they had lifted. For each lift, we determined the initial peak rate of change of vertical load-force rate and the load-phase duration, which provide estimates of predicted object weight. Analysis of the 10th lift of the small cube revealed no effects of surface material, indicating participants learned the appropriate forces required to lift the small cube regardless of object appearance. However, both surface material and core material of the small cube affected the 1st lift of the large block. We conclude that sensorimotor memory related to object density can contribute to weight prediction when lifting novel objects but also that long-term priors related to material properties can influence the prediction.

scholarly journals Effects of TMS over the anterior intraparietal area on anticipatory fingertip force scaling and the size-weight illusion

2020 ◽  
Author(s):  
Vonne van Polanen ◽  
Gavin Buckingham ◽  
Marco Davare
Keyword(s):  
Primary Motor Cortex ◽  
Weight Perception ◽  
Control Area ◽  
Equal Weight ◽  
Small Object ◽  
Object Size ◽  
Neural Underpinnings ◽  
Weight Illusion ◽  
Force Scaling

ABSTRACTIn skilled object lifting, fingertip forces need to be carefully scaled to object weight, which can be inferred from object properties, such as size or material. This anticipatory force scaling ensures smooth and efficient lifting movements. However, even with accurate motor plans, weight perception can still be biased. In the size-weight illusion, objects of different size but equal weight are perceived to differ in heaviness, with the small object perceived to be heavier than the large object. The neural underpinnings of the size-weight illusion and anticipatory force scaling to object size are largely unknown. In this study, we hypothesized a possible role of the anterior intraparietal cortex (aIPS) in predictive force scaling and the size-weight illusion, which we investigated by applying continuous theta burst stimulation (cTBS) prior to participants lifting objects designed to induce the size-weight illusion. Participants received cTBS over aIPS, the primary motor cortex (control area), or sham stimulation. We found no evidence that aIPS stimulation affected the size-weight illusion. Small effects were, however, found on anticipatory force scaling, where grip force was less tuned to object size during initial lifts. These findings suggest that, while aIPS might be peripherally involved in sensorimotor prediction, other brain areas underpin the processes that mediate the size-weight illusion.

scholarly journals Perceiving and acting upon weight illusions in the absence of somatosensory information

2016 ◽  
Vol 115 (4) ◽  
pp. 1946-1953 ◽  
Author(s):  
Gavin Buckingham ◽  
Elizabeth Evgenia Michelakakis ◽  
Jonathan Cole
Keyword(s):  
Material Properties ◽  
Weight Perception ◽  
Visual Appearance ◽  
Fingertip Force ◽  
Object Weight ◽  
Somatosensory Information ◽  
Novel Objects ◽  
Weight Illusion ◽  
Fingertip Forces ◽  
Weight Illusions

When lifting novel objects, individuals' fingertip forces are influenced by a variety of cues such as volume and apparent material. This means that heavy-looking objects tend to be lifted with more force than lighter-looking objects, even when they weigh the same amount as one another. Expectations about object weight based on visual appearance also influence how heavy an object feels when it is lifted. For instance, in the “size-weight illusion,” small objects feel heavier than equally weighted large objects. Similarly, in the “material-weight illusion,” objects that seem to be made from light-looking materials feel heavier than objects of the same weight that appear to be made from heavy-looking materials. In this study, we investigated these perceptual and sensorimotor effects in IW, an individual with peripheral deafferentation (i.e., a loss of tactile and proprioception feedback). We examined his perceptions of heaviness and fingertip force application over repeated lifts of objects that varied in size or material properties. Despite being able to report real weight differences, IW did not appear to experience the size- or material-weight illusions. Furthermore, he showed no evidence of sensorimotor prediction based on size and material cues. The results are discussed in the context of forward models and their possible influence on weight perception and fingertip force control.

HUBUNGAN TUNGAU DEBU RUMAH, PAPARAN ASAP ROKOK DAN RIWAYAT PENYAKIT KELUARGA TERHADAP KEJADIAN ASMA BRONKIAL PADA ANAK USIA 5 – 10 TAHUN DI WILAYAH KERJA PUSKESMAS LEMPAKE KOTA SAMARINDA TAHUN 2016

2018 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Sri Evi New Yearsi Pangadongan ◽  
Agustina Rahyu ◽  
Selvy Pasulu
Keyword(s):  
Cigarette Smoke ◽  
Bronchial Asthma ◽  
Sampling Technique ◽  
Total Sample ◽  
Control Group ◽  
Case Group ◽  
Chi Square ◽  
History Of ◽  
Weather Changes ◽  
And Gender

Bronchial Asthma generally starts from childhood which is condition where respiration channel experiences constriction because of hyperactivity with some specific stimulation which cause inflammation. Some risk factors are smoking exposure of cigarette smoke, weather changes, mite on house dirt, pet and history of family sickness. The purpose of this research is to know Relation of mite on house dirt, exposure of cigarette smoke  and history of family sickness with bronchial asthma incident to child 5 – 10  years old on working area of Puskesmas Lempake Samarinda City in 2016. Method which used was analytic survey with Case Control approaching. The total sample was 36 children which consisted of 18 case group and 18 control group with matching by using age and gender which submitted with Purposive Sampling technique. Data Analysis used Chi Square with wrong degree α = 0,005. The result showed that there was relation of mite of house dirt (p = 0,006), history of family sickness (p = 0,001) and no relation with exposure of cigarette smoke (p = 0,370) with bronchial asthma incident to child 5 – 10 years old on working area of Puskesmas Lempake Samarinda City in 2016.

The evaluation of nasal mucociliary clearance in patients with Helicobacter pylori infection

2019 ◽  
Vol 133 (03) ◽  
pp. 220-223
Author(s):  
S Üstün Bezgin ◽  
T Çakabay ◽  
K Irak ◽  
M Koçyiğit ◽  
B Serin Keskineğe ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Mucociliary Clearance ◽  
Endoscopic Examination ◽  
Control Group ◽  
Clearance Time ◽  
Saccharine Test ◽  
Significant Difference ◽  
And Gender ◽  
H Pylori ◽  
Nasal Mucociliary Clearance

AbstractObjectiveThis study aimed to examine nasal mucociliary clearance time in patients with Helicobacter pylori infection.MethodsFifty patients who were newly diagnosed with H pylori infection using gastric biopsy in the gastroenterology out-patient clinic, and 50 age- and gender-matched healthy adults who were admitted to the otorhinolaryngology out-patient clinic, were included in this study. After an otorhinolaryngological examination (anterior rhinoscopy and nasal endoscopic examination), the nasal mucociliary clearance time of each subject was calculated using the saccharine test.ResultsThe mean mucociliary clearance time was 06:29 ± 3:31 minutes (range, 00:55–15:19 minutes) in the control group and 10:12 ± 06:09 minutes (range, 01:28–32:00 minutes) in the study group. Comparisons of the two groups revealed a statistically significant difference (p = 0.002).ConclusionNasal mucociliary clearance time was significantly increased in patients with H pylori infection. The results suggest that H pylori infection may have an unfavourable effect on nasal mucociliary clearance.

scholarly journals Optimal Timing for Primary Early Endoscopic Dacryocystorhinostomy in Acute Dacryocystitis

2021 ◽  
Vol 10 (10) ◽  
pp. 2161
Author(s):  
Jae Yun Sung ◽  
Ju Mi Kim ◽  
Jae Yul Hwang ◽  
Kyoung Nam Kim ◽  
Jae Young Kim ◽  
...  
Keyword(s):  
Subgroup Analysis ◽  
Surgical Outcomes ◽  
Timing Of Surgery ◽  
Secondary Outcome ◽  
Control Group ◽  
Optimal Timing ◽  
Secondary Outcome Measure ◽  
Success Rates ◽  
Endoscopic Dacryocystorhinostomy ◽  
And Gender

Purpose: To evaluate the surgical outcomes of primary early endoscopic dacryocystorhinostomy (EnDCR) in acute dacryocystitis (AD) and to determine the optimal timing for surgery. Methods: A retrospective review of medical records was performed on consecutive patients who underwent primary early EnDCR (within 1 week) for AD between May 2010 and June 2020 (AD group) and an age- and gender-matched control group of NLDO patients who underwent EnDCR (non-AD group). The primary outcome measures were the surgical outcomes at the final follow-up examination. The secondary outcome measure was the clinical course of AD patients. Subgroup analysis was performed to determine the optimal timing of surgery by comparing the outcomes of very early EnDCR (within 3 days) and those of early EnDCR (between 4 and 7 days). Results: Forty-one patients were included in the AD group and 82 patients in the non-AD group. The anatomical and functional success rates were 87.8% and 82.9% in the AD group, and 91.5% and 84.1% in the non-AD group, which were not significantly different between the two groups (p = 0.532 and p = 0.863). In the AD group, the mean times for pain relief and resolution of swelling after surgery were 2.4 and 6.5 days after surgery, respectively. In the subgroup analysis according to the timing of surgery, the time for symptom resolution after diagnosis, the length of hospital stays, and the duration of antibiotic treatments were significantly shorter after very early EnDCR (all ps < 0.05), whereas the surgical outcomes were not different between the two groups (p = 1.000). Conclusions: Primary early EnDCR is a safe and effective procedure for the treatment of AD. In particular, very early EnDCR performed within 3 days leads to faster recovery and shortens the course of antibiotic treatment.

Perceptual Speech Outcomes After Early Primary Palatal Repair in Ugandan Patients With Cleft Palate

2020 ◽  
pp. 105566562098024
Author(s):  
Kim Bettens ◽  
Laura Bruneel ◽  
Cassandra Alighieri ◽  
Daniel Sseremba ◽  
Duncan Musasizib ◽  
...  
Keyword(s):  
Cleft Palate ◽  
Cleft Lip ◽  
Speech Therapy ◽  
Cleft Lip And Palate ◽  
Control Group ◽  
English Speaking ◽  
And Gender ◽  
Early Primary ◽  
Velopharyngeal Function ◽  
Normal Speech

Objective: To provide speech outcomes of English-speaking Ugandan patients with a cleft palate with or without cleft lip (CP±L). Design: Prospective case–control study. Setting: Referral hospital for patients with cleft lip and palate in Uganda. Participants: Twenty-four English-speaking Ugandan children with a CP±L (15 boys, 9 girls, mean 8.4 years) who received palatal closure prior to 6 months of age and an age- and gender-matched control group of Ugandan children without cleft palate. Interventions: Comparison of speech outcomes of the patient and control group. Main Outcome Measures: Perceptual speech outcomes including articulation, resonance, speech understandability and acceptability, and velopharyngeal composite score (VPC-sum). Information regarding speech therapy, fistula rate, and secondary surgery. Results: Normal speech understandability was observed in 42% of the patients, and 38% were judged with normal speech acceptability. Only 16% showed compensatory articulation. Acceptable resonance was found in 71%, and 75% of the patients were judged perceptually to present with competent velopharyngeal function based on the VPC-sum. Additional speech intervention was recommended in 25% of the patients. Statistically significant differences for all these variables were still observed with the control children ( P < .05). Conclusions: Overall, acceptable speech outcomes were found after early primary palatal closure. Comparable or even better results were found in comparison with international benchmarks, especially regarding the presence of compensatory articulation. Whether this approach is transferable to Western countries is the subject for further research.

scholarly journals Headache and musculoskeletal pain in school children are associated with uncorrected vision problems and need for glasses: a case–control study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hanne-Mari Schiøtz Thorud ◽  
Rakel Aurjord ◽  
Helle K. Falkenberg
Keyword(s):  
Musculoskeletal Pain ◽  
School Children ◽  
School Health ◽  
Upper Body ◽  
Musculoskeletal Symptoms ◽  
Control Group ◽  
Pain Group ◽  
And Gender ◽  
Years Lived With Disability ◽  
Near Work

AbstractMusculoskeletal pain and headache are leading causes of years lived with disability, and an escalating problem in school children. Children spend increasingly more time reading and using digital screens, and increased near tasks intensify the workload on the precise coordination of the visual and head-stabilizing systems. Even minor vision problems can provoke headache and neck- and shoulder (pericranial) pain. This study investigated the association between headaches, pericranial tenderness, vision problems, and the need for glasses in children. An eye and physical examination was performed in twenty 10–15 year old children presenting to the school health nurse with headache and pericranial pain (pain group), and twenty age-and-gender matched classmates (control group). The results showed that twice as many children in the pain group had uncorrected vision and needed glasses. Most children were hyperopic, and glasses were recommended mainly for near work. Headache and pericranial tenderness were significantly correlated to reduced binocular vision, reduced distance vision, and the need for new glasses. That uncorrected vision problems are related to upper body musculoskeletal symptoms and headache, indicate that all children with these symptoms should have a full eye examination to promote health and academic performance.

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