scholarly journals Practice Reduces the Effect of a Ponzo Illusion on Precision Grasping but not Manual Estimation

2012 ◽  
Vol 12 (9) ◽  
pp. 1093-1093 ◽  
Author(s):  
R. L. Whitwell ◽  
G. Buckingham ◽  
P. A. Chouinard ◽  
J. M. Mikkila ◽  
S. Fortunato ◽  
...  
Keyword(s):  
Ponzo Illusion ◽  
Manual Estimation ◽  
Precision Grasping

Framing theory and the Ponzo illusion

1997 ◽  
Author(s):  
William Prinzmetal ◽  
Arthur P. Shimamura ◽  
Michelle Mikolinski
Keyword(s):  
Ponzo Illusion ◽  
Framing Theory

scholarly journals Susceptibility of rhesus monkeys (Macaca mulatta) to the Ponzo illusion

1983 ◽  
Vol 21 (6) ◽  
pp. 476-478 ◽  
Author(s):  
Kathryn A. L. Bayne ◽  
Roger T. Davis
Keyword(s):  
Macaca Mulatta ◽  
Rhesus Monkeys ◽  
Ponzo Illusion

The magnitude of the Ponzo illusion as a function of age for large and for small stimulus configurations

1971 ◽  
Vol 25 (2) ◽  
pp. 97-99 ◽  
Author(s):  
Marcia Farquhar ◽  
Herschel W. Leibowitz
Keyword(s):  
Ponzo Illusion ◽  
Small Stimulus

Force Control Strategy of Five-Digit Precision Grasping With Aligned and Unaligned Configurations

2022 ◽  
pp. 001872082110409
Author(s):  
Po-Tsun Chen ◽  
Hsiu-Yun Hsu ◽  
You-Hua Su ◽  
Chien-Ju Lin ◽  
Hsiao-Feng Chieh ◽  
...  
Keyword(s):  
Control Strategy ◽  
Force Control ◽  
Task Type ◽  
Applied Force ◽  
Force Variability ◽  
Force Transducers ◽  
Task Requirements ◽  
Power Grasp ◽  
Precision Grasping ◽  
Large Moment

Objective To investigate the digit force control during a five-digit precision grasp in aligned (AG) and unaligned grasping (UG) configurations. Background The effects of various cylindrical handles for tools on power grasp performance have been previously investigated. However, there is little information on force control strategy of precision grasp to fit various grasping configurations. Method Twenty healthy young adults were recruited to perform a lift-hold-lower task. The AG and UG configurations on a cylindrical simulator with force transducers were adjusted for each individual. The applied force and moment, the force variability during holding, and force correlations between thumb and each finger were measured. Result No differences in applied force, force correlation, repeatability, and variability were found between configurations. However, the moments applied in UG were significantly larger than those in AG. Conclusion The force control during precision grasp did not change significantly across AG and UG except for the digit moment. The simulator is controlled efficiently with large moment during UG, which is thus the optimal configuration for precision grasping with a cylindrical handle. Further research should consider the effects of task type and handle design on force control, especially for individuals with hand disorders. Application To design the handle of specific tool, one should consider the appropriate configuration according to the task requirements of precision grasping to reduce the risk of accumulating extra loads on digits with a cylindrical handle.

scholarly journals Influences of orientation on the Ponzo, contrast, and Craik-O’Brien-Cornsweet illusions

2019 ◽  
Vol 82 (4) ◽  
pp. 1896-1911
Author(s):  
Leo Poom
Keyword(s):  
Real World ◽  
Physical Environment ◽  
Ponzo Illusion ◽  
Simultaneous Contrast ◽  
Size Constancy ◽  
3D Object ◽  
Railway Tracks ◽  
Left Right Asymmetry ◽  
Prior Experiences

AbstractExplanations of the Ponzo size illusion, the simultaneous contrast illusion, and the Craik-O’Brien-Cornsweet brightness illusions involve either stimulus-driven processes (assimilation, enhanced contrast, and anchoring) or prior experiences. Real-world up-down asymmetries for typical direction of illumination and ground planes in our physical environment should influence these illusions if they are experience based, but not if they are stimulus driven. Results presented here demonstrate differences in illusion strengths between upright and inverted versions of all three illusions. A left-right asymmetry of the Cornsweet illusion was produced by manipulating the direction of illumination, providing further support for the involvement of an experience-based explanation. When the inducers were incompatible with the targets being located at the different distances, the Ponzo illusion persisted and so did the influence from orientation, providing evidence for involvement of processes other than size constancy. As defined here, upright for the brightness illusions is consistent with an interpretation of a shaded bulging surface and a 3D object resulting from a light-from-above assumption triggering compensation for varying illumination. Upright for the Ponzo illusion is consistent with the inducers in the form of converging lines being interpreted as railway tracks receding on the ground triggering size constancy effects. The implications of these results, and other results providing evidence against experience-based accounts of the illusions, are discussed.

Precision grasping in humans: from motor control to cognition

2007 ◽  
Vol 17 (6) ◽  
pp. 644-648 ◽  
Author(s):  
Etienne Olivier ◽  
Marco Davare ◽  
Michael Andres ◽  
Luciano Fadiga
Keyword(s):  
Motor Control ◽  
Precision Grasping
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