scholarly journals Sensorimotor Memory for Object Weight is Based on Previous Experience During Lifting, Not Holding

2018 ◽  
Author(s):  
Vonne van Polanen ◽  
Marco Davare
Keyword(s):  
Motor Command ◽  
Object Manipulation ◽  
Recent Experience ◽  
List Type ◽  
Holding Period ◽  
Object Weight ◽  
Object Lifting ◽  
Time Period ◽  
Sensorimotor Memory ◽  
Force Planning

ABSTRACTTo allow skilled object manipulation, the brain must generate a motor command specifically tailored to the object properties. For instance, in object lifting, the forces applied by the fingertips must be scaled to the object’s weight. When lifting a series of objects, forces are usually scaled according to recent experience from previously lifted objects, an effect often referred to as sensorimotor memory. In this study, we investigated the specific time period during which stored information from previous object manipulation is used to mediate sensorimotor memory. More specifically, we examined whether sensorimotor memory was based on weight information obtained between object contact and lift completion (lifting phase) or during stable holding (holding phase). Participants lifted objects in virtual reality that could increase or decrease in weight after the object was lifted and held in the air. In this way, we could distinguish whether the force planning in the next lift was scaled depending on weight information gathered from either the dynamic lifting or static holding period. We found that force planning was based on the previous object weight experienced during the lifting, but not holding, phase. This suggest that the lifting phase, while merely lasting a few hundred milliseconds, is a key time period for building up internal object representations used for planning future hand-object interactions.HIGHLIGHTSWhen lifting objects, fingertip force scaling is based on the most recent liftWe investigated what time period is critical for acquiring sensorimotor memorySensorimotor memory is based on weight experienced during previous lift, not holdThe lifting phase is a key period for building up internal models of object lifting

scholarly journals The observation of explicit and implicit visuomotor cues can drive predictive motor control

2019 ◽  
Author(s):  
Guy Rens ◽  
Marco Davare
Keyword(s):  
Motor Control ◽  
Object Representation ◽  
Motor Command ◽  
Object Weight ◽  
Object Lifting ◽  
Sixth Trial ◽  
Force Scaling ◽  
Object Interactions ◽  
Fingertip Forces

AbstractRecent studies have highlighted that the observation of hand-object interactions can influence perceptual weight judgements made by an observer. Moreover, observing explicit motor errors during object lifting allows individuals to update their internal sensorimotor representation about object weight. Embodying observed visuomotor cues for the planning of a motor command further enables individuals to accurately scale their fingertip forces when subsequently lifting the same object. However, it is still unknown whether observation of a skilled lift is equally able to mediate predictive motor control in the observer. Here, we tested this hypothesis by asking participants to grasp and lift a manipulandum after observing an actor’s lift. The object weight changed unpredictably (light or heavy) every third to sixth trial performed by the actor. Participants were informed that they would always lift the same weight as the actor and that, based on the experimental condition, they would have to observe skilled or erroneously performed lifts. Our results revealed that the observation of both skilled and erroneously performed lifts allows participants to update their internal sensorimotor object representation, in turn enabling them to predict force scaling accurately. These findings suggest that the observation of explicit as well as implicit visuomotor cues are embodied in the observer’s motor repertoire and can drive changes in predictive motor control.

scholarly journals Corticospinal excitability underlying digit force planning for grasping in humans

2014 ◽  
Vol 111 (12) ◽  
pp. 2560-2569 ◽  
Author(s):  
Pranav Parikh ◽  
Marco Davare ◽  
Patrick McGurrin ◽  
Marco Santello
Keyword(s):  
Primary Motor Cortex ◽  
Single Pulse ◽  
Intracortical Inhibition ◽  
Corticospinal Excitability ◽  
Reach To Grasp ◽  
Grasp Planning ◽  
Sensorimotor Memory ◽  
Force Planning ◽  
Intracortical Inhibition And Facilitation

Control of digit forces for grasping relies on sensorimotor memory gained from prior experience with the same or similar objects and on online sensory feedback. However, little is known about neural mechanisms underlying digit force planning. We addressed this question by quantifying the temporal evolution of corticospinal excitability (CSE) using single-pulse transcranial magnetic stimulation (TMS) during two reach-to-grasp tasks. These tasks differed in terms of the magnitude of force exerted on the same points on the object to isolate digit force planning from reach and grasp planning. We also addressed the role of intracortical circuitry within primary motor cortex (M1) by quantifying the balance between short intracortical inhibition and facilitation using paired-pulse TMS on the same tasks. Eighteen right-handed subjects were visually cued to plan digit placement at predetermined locations on the object and subsequently to exert either negligible force (“low-force” task, LF) or 10% of their maximum pinch force (“high-force” task, HF) on the object. We found that the HF task elicited significantly smaller CSE than the LF task, but only when the TMS pulse coincided with the signal to initiate the reach. This force planning-related CSE modulation was specific to the muscles involved in the performance of both tasks. Interestingly, digit force planning did not result in modulation of M1 intracortical inhibitory and facilitatory circuitry. Our findings suggest that planning of digit forces reflected by CSE modulation starts well before object contact and appears to be driven by inputs from frontoparietal areas other than M1.

scholarly journals Cured primary hyperparathyroidism after fine-needle aspiration biopsy-induced parathyroid disappearance

2017 ◽  
Vol 2017 ◽  
Author(s):  
Elda Kara ◽  
Elisa Della Valle ◽  
Sara De Vincentis ◽  
Vincenzo Rochira ◽  
Bruno Madeo
Keyword(s):  
Primary Hyperparathyroidism ◽  
Fine Needle Aspiration ◽  
Needle Aspiration ◽  
Complete Disappearance ◽  
List Type ◽  
Fine Needle ◽  
Time Period ◽  
History Of

Summary Spontaneous or fine-needle aspiration (FNAB)-induced remission of primary hyperparathyroidism (PHPT) may occur, especially for cystic lesions. However, the disease generally relapses over a short time period. We present a case of PHPT due to an enlarged hyperfunctioning parathyroid that underwent long-term (almost 9 years) clinical and ultrasonographic remission after the disappearance of the lesion following ultrasound (US)-assisted FNAB. A 67-year-old woman with PHPT underwent biochemical and US examinations that confirmed the diagnosis and showed a lesion suggestive for parathyroid adenoma or hyperplasia. US-FNAB of the lesion confirmed its parathyroid nature by means of elevated levels of parathyroid hormone within the needle washing fluid. At the second visit, the patient referred slight neck swelling that resolved spontaneously in the days after the US-FNAB. At subsequent follow-up, the enlarged parathyroid was not found; it was visible neither with US nor with magnetic resonance imaging. Biochemical remission persists after 9 years. This is the first reported case of cure of PHPT after US-FNAB performed on a hyperfunctioning parathyroid resulting in its complete disappearance over a period of 9 years of negative biochemical and ultrasonographic follow-up. Learning points: Spontaneous or fine-needle aspiration-induced remission of primary hyperparathyroidism can occur. Both circumstances may present disease relapse over a variable time period, but definite remission is also possible even though long-term periodic follow-up should be performed. Parathyroid damage should be ruled out in case of neck symptomatology after parathyroid fine-needle aspiration or spontaneous symptomatology in patients with history of primary hyperparathyroidism.

Modulation of LH-secretion in ovariectomized ewes by constant infusions of oestradiol and 4-hydroxyoestradiol: effects of varying infusion times and of high oestrogen doses

1986 ◽  
Vol 113 (2) ◽  
pp. 219-225 ◽  
Author(s):  
G. Emons ◽  
H. Schuppe ◽  
M. Peter ◽  
C. Brack ◽  
P. Ball
Keyword(s):  
Plasma Levels ◽  
Critical Time ◽  
List Type ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Oestrogen Treatment ◽  
Time Period ◽  
Lh Secretion ◽  
Positive Effect ◽  
Intracellular Action

Abstract. Ovariectomized ewes were infused for different times (2–24 h) during the breeding season (September to Februray) with oestradiol (E2, 2 μg/h) or the catecholoestrogen 4-hydroxyoestradiol (4-OHE2, 10 μg/h). At these infusion rates comparable plasma levels of E2 and 4-OHE2 were obtained when steady state was reached after 3 h (E2: 20 ± 4 pg/ml; 4-OHE2: 22 ± 3 pg/ml). When E2 was infused for at least 6 h, all animals had significant LH-surges, starting 14-16 h after the beginning of oestrogen treatment, even when E2 was infused for up to 24 h. 4-OHE2, however, had only to be infused for 4 h to induce significant LH-surges in all animals tested. When E2 was infused for 12 h at a rate of 100 μg/h, the LH-surges in these ewes were significantly lower than the LH-surges in the same animals treated for 12 h with E2at a rate of 2 μg/h. These data indicate: Once E2 has been administered at a specific infusion rate for a critical time period of 6 h, LH-surges occur, no matter whether the E2-infusion is continued or stopped. For the catecholoestrogen 4-OHE2 this critical time period amounts only to 4 h, if comparable plasma levels of either oestrogen are achieved. This might hint at a prolonged intracellular action of 4-OHE2 as compared to E2. At extremely high infusion rates of E2 (100 μg/h for 12 h) the positive oestrogen effect is significantly impaired, a finding supporting the concept of a bell-shaped dose-response relationship between oestrogens and their positive effect on LH-secretion.

scholarly journals The sensorimotor system minimizes prediction error for object lifting when the object’s weight is uncertain

2017 ◽  
Vol 118 (2) ◽  
pp. 649-651
Author(s):  
Jack Brooks ◽  
Anne Thaler
Keyword(s):  
Prediction Error ◽  
Environmental Uncertainty ◽  
Object Manipulation ◽  
Sensorimotor System ◽  
Visually Guided ◽  
Visually Guided Reaching ◽  
Object Lifting ◽  
Reliable Mechanism

A reliable mechanism to predict the heaviness of an object is important for manipulating an object under environmental uncertainty. Recently, Cashaback et al. (Cashaback JGA, McGregor HR, Pun HCH, Buckingham G, Gribble PL. J Neurophysiol 117: 260–274, 2017) showed that for object lifting the sensorimotor system uses a strategy that minimizes prediction error when the object’s weight is uncertain. Previous research demonstrates that visually guided reaching is similarly optimized. Although this suggests a unified strategy of the sensorimotor system for object manipulation, the selected strategy appears to be task dependent and subject to change in response to the degree of environmental uncertainty.

Amy Winehouse Foundation young persons’ substance use survey–pilot findings

2017 ◽  
Vol 41 (S1) ◽  
pp. S872-S872
Author(s):  
G. Ofori-Attah ◽  
N. Knights ◽  
T. Mazhari
Keyword(s):  
Substance Use ◽  
Online Survey ◽  
Reliability And Validity ◽  
Survey Method ◽  
List Type ◽  
Technical Problems ◽  
Time Period ◽  
Teachers And Students ◽  
Competing Interest ◽  
Short Time

IntroductionGovernment-funded research indicates the prevalence of substance use in this age group is decreasing. However, anecdotal evidence suggests otherwise.Previous surveys have been limited by:— difficulty recruiting schools;— the range of substances included;— paper surveys.ObjectivesTo determine whether a secure online survey method improves substance use prevalence data collection in school age adolescents.MethodAn online survey was created following literature review, and assessment of the reliability and validity of existing surveys. A comprehensive range of substances were included. A total of 750 students (11–16 yrs) from a mainstream school in Lancashire completed the survey during a supervised classroom session. Focus groups were conducted with students and teachers.ResultsNo technical problems were encountered and survey data was securely transferred to Excel allowing instant analysis.Teachers felt the survey would be unproblematic to administer independently and found the inclusion of substances such as legal highs, and energy drinks, especially relevant.Most students completed the survey within the session and reported a positive experience, although some difficulties understanding wording were mentioned. They felt an online survey improved confidentiality (and therefore honesty) and was easier to fill in. However, there was concern about teachers reading their responses.ConclusionsA secure online survey may be acceptable to both teachers and students, and enables the collection of hundreds of surveys in a short time period. It also improves analysis techniques.Further analysis of whether there is a teacher-versus-researcher supervision effect on the honesty of student responses is required.Disclosure of interestThe authors have not supplied their declaration of competing interest.

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 Infants’ prospective control during object manipulation in an uncertain environment

2018 ◽  
Author(s):  
Janna M. Gottwald ◽  
Gustaf Gredebäck
Keyword(s):  
Motion Capture ◽  
Visual Information ◽  
Color Condition ◽  
Significant Interaction Effect ◽  
Prospective Control ◽  
Object Weight ◽  
Sensorimotor Memory ◽  
Sensorimotor Information ◽  
Different Color ◽  
Movement Unit

This study investigates how infants use visual and sensorimotor information to prospectively control their actions. We gave 14-month-olds two objects of different weight and observed how high they were lifted, using a Qualisys Motion Capture System. In one condition, the two objects were visually distinct (different color condition) in another they were visually identical (same color condition). Lifting amplitudes of the first movement unit were analyzed in order to assess prospective control. Results demonstrate that infants lifted a light object higher than a heavy object, especially when vision could be used to assess weight (different color condition). When being confronted with two visually identical objects of different weight (same color condition), infants showed a different lifting pattern than what could be observed in the different color condition, expressed by a significant interaction effect between object weight and color condition on lifting amplitude. These results indicate that (a) visual information about object weight can be used to prospectively control lifting actions and that (b) infants are able to prospectively control their lifting actions even without visual information about object weight. We argue that infants, in the absence of reliable visual information about object weight, heighten their dependence on non-visual information (tactile, sensorimotor memory) in order to estimate weight and pre-adjust their lifting actions in a prospective manner.

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