scholarly journals Errors in pointing are due to approximations in sensorimotor transformations

1989 ◽  
Vol 62 (2) ◽  
pp. 595-608 ◽  
Author(s):  
J. F. Soechting ◽  
M. Flanders
Keyword(s):  
Muscle Activity ◽  
Target Location ◽  
Frame Of Reference ◽  
Frames Of Reference ◽  
Final Position ◽  
Experimental Conditions ◽  
Extrapersonal Space ◽  
Sensorimotor Transformations ◽  
One Step ◽  
Intrinsic Frame

1. We define an extrinsic frame of reference to represent the location of a point in extrapersonal space relative to a human subject's shoulder, and we define an intrinsic frame of reference to represent the orientation of the arm and forearm. 2. We examined the relations between coordinates in the extrinsic and intrinsic frames of reference under two experimental conditions: when subjects made inaccurate movements by pointing to virtual targets in the dark and when they made accurate movements by pointing to actual targets in the light. 3. When subjects made inaccurate movements, there was a close-to-linear relationship between the orientation angles of the arm (intrinsic coordinates) at its final position and the extrinsic coordinates of the target. When they made accurate movements, these relationships were more nonlinear. 4. Specifically, arm and forearm elevations depended principally on target distance and elevation, whereas the two yaw angles depended mainly on the target's azimuth. 5. We propose that errors in pointing occur because subjects implement a linear approximation to the transformation from extrinsic to intrinsic coordinates and that this transformation is one step in the process of transforming a visually derived representation of target location into an appropriate pattern of muscle activity.

scholarly journals Perspective construal techniques in indirect non-referential naming

2020 ◽  
pp. 188-204
Author(s):  
M. I. Kiose ◽  
Keyword(s):  
Correlation Analysis ◽  
Frame Of Reference ◽  
Frames Of Reference ◽  
Final Position ◽  
Reference Coordinate System ◽  
Complex Procedure ◽  
Focus Type ◽  
Comparative Constructions ◽  
Reference Distance ◽  
Fictive Motion

The research explores the perspective construal techniques applied in predicate indirect noun groups in Russian. In this case, the discourse perspective is construed with a highly salient ob-ject of perspective in the construed frame of reference. To achieve this effect, the speaker / narrator chooses a particular type of predicate indirect noun groups, such as predicate con-structions with the verbs of fictive motion, appearance, and being (existence) or comparative constructions. Each of these construction types demonstrates its own linguistic and cognitive features, which are used to apply various perspectivization techniques to ensure that its inter-pretation will proceed successfully. To detect these techniques, a complex procedure is applied. Hand-selected fragments analysis followed by corpus statistic and correlation analysis help define the parameters and values in predicate indirect noun group constructions. These parameters are referential (bodily modus type, referent type, referent focus type), lexical (first / repeated lexeme use, type of attribute in pre-position, intensifier type in pre-position), syntactic (sentence initial / final position, position before a clause, co-reference distance in words and propositions) and textual ones (textual role, new microevent introduction). Vari-ance analysis has revealed a group of parameters typical for the studied construction types of predicate indirect noun groups. Parametric results allow describe the typical techniques of object mental scanning, object construal, frames of reference (coordinate system) construal. These include the techniques of mental path shortening / prolongation, embodiment con- strual alleviation / constraining, animated / non-animated object construal, stability / instabil-ity of frames of reference, etc.

Relationship between Frames of Reference and Mirror-Image Reversals

Perception ◽  
10.1068/p5529 ◽  
2007 ◽  
Vol 36 (7) ◽  
pp. 1049-1056 ◽  
Author(s):  
Hirokazu Yoshimura ◽  
Tatsuo Tabata
Keyword(s):  
Mirror Image ◽  
Frame Of Reference ◽  
The Other ◽  
Frames Of Reference ◽  
Physical Aspect ◽  
Other Hand ◽  
Extended Problem ◽  
Left Right Asymmetry ◽  
Common Frame Of Reference ◽  
Intrinsic Frame

The mirror puzzle related to the perception of mirror images as left–right reversed can be more fully understood by considering an extended problem that includes also the perception of mirror images that are not left–right reversed. The purpose of the present study is to clarify the physical aspect of this extended problem logically and parsimoniously. Separate use of the intrinsic frame of reference that belongs to the object and one that belongs to its mirror image always leads to the perception of left–right reversal when the object has left–right asymmetry; on the other hand, the perception of left–right nonreversal is always due to the application of a common frame of reference to the object and its mirror image.

Sensorimotor representations for pointing to targets in three-dimensional space

1989 ◽  
Vol 62 (2) ◽  
pp. 582-594 ◽  
Author(s):  
J. F. Soechting ◽  
M. Flanders
Keyword(s):  
Target Location ◽  
Dimensional Space ◽  
Visual Representation ◽  
Three Dimensional ◽  
Arm Movement ◽  
Experimental Conditions ◽  
Extrapersonal Space ◽  
Target Locations ◽  
Sensorimotor Representations ◽  
Three Dimensional Space

1. The accuracy with which subjects pointed to targets in extrapersonal space was assessed under a variety of experimental conditions. 2. When subjects pointed in the dark to remembered target locations, they made substantial errors. Errors in distance, measured from the shoulder to the target, were sometimes as much as 15 cm. Errors in direction, also measured from the shoulder, were smaller. 3. An analysis of the information transmitted by the location of the subject's finger about the location of the target showed that the information about the target's distance was consistently lower than the information about its direction. 4. The errors in distance persisted when subjects had their arm in view and pointed in the light to remembered target locations. 5. The errors were much smaller when subjects used a pointer to point to the target or when they were asked to reproduce the position of their finger after it had been passively moved to the target. 6. From these findings we conclude that subjects have a reasonably accurate visual representation of target location and are able to effectively use kinesthetically derived information about target location. We therefore suggest that errors in pointing result from errors in the sensorimotor transformation from the visual representation of the target location to the kinematic representation of the arm movement.

The intrinsic frame of reference and the Dhivehi ‘FIBO’ system

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jonathon Lum
Keyword(s):  
Borderline Case ◽  
Frame Of Reference ◽  
Spatial Language ◽  
Frames Of Reference ◽  
Speech Communities ◽  
Language And Cognition ◽  
Theoretical Issues ◽  
Intrinsic Frame

Abstract While geocentric and relative frames of reference have figured prominently in the literature on spatial language and cognition, the intrinsic frame of reference has received less attention, though various subtypes of the intrinsic frame have been proposed. This paper presents a revised classification of the intrinsic frame, distinguishing between three subtypes: a ‘direct’ subtype, an ‘object-centered’ subtype and a ‘figure-anchored’ subtype, with a cross-cutting distinction between ‘function-based’ and ‘shape-based’ systems. In addition, the ‘FIBO’ (front = inner, back = outer) system in Dhivehi is analyzed as an example of a borderline case, with some important features of the intrinsic frame but also some differences, presenting a challenge for existing frame of reference classifications. The rotational properties of these various systems are also considered. The analysis underscores the considerable diversity within intrinsic systems but also points to a closer relationship between intrinsic and extrinsic frames than has previously been appreciated. This may have implications for broader theoretical issues including how frames of reference are acquired, how speech communities come to use different frames and whether patterns of frame use in discourse shape patterns of non-verbal frame use.

Spatial cognition and linguistic expression

2004 ◽  
Vol 2 ◽  
pp. 261-283
Author(s):  
Kazuko Shinohara ◽  
Yoshihiro Matsunaka
Keyword(s):  
Coordinate System ◽  
Experimental Method ◽  
Spatial Relations ◽  
Frame Of Reference ◽  
Frames Of Reference ◽  
Linguistic Expression ◽  
Ground Object ◽  
Intrinsic Orientation ◽  
Definition Of ◽  
Intrinsic Frame

This paper analyzes frames of reference involved in linguistic expression of spatial relations of objects, using an experimental method. Objects with and without intrinsic orientation are used as the figure object, and it is demonstrated that there exists in Japanese a phenomenon we call ‘figure-aligned mapping’, where the coordinate system on the figure object is projected onto the ground object. This is what previous studies have not reported or argued. We claim that this figure-aligned mapping belongs to the intrinsic frame of reference among the three (intrinsic, relative, and absolute) frames of reference proposed by Levinson, and some revision of his definition of the intrinsic frame is proposed so that figure-aligned mapping can be accommodated in it. The result of this study confirms the importance of the notion of coordinate system in the discussion of frames of reference.

One-Step Fabrication and Functionalization of Nanostructured Silicon Surfaces for Advanced Sensing Applications

2020 ◽  
Vol 312 ◽  
pp. 154-159
Author(s):  
Alexander Yuryevich Mironenko ◽  
Mikhail Tutov ◽  
Alexander Konstantinovich Chepak ◽  
Eugeny Mitsai ◽  
Alexander A. Sergeev ◽  
...  
Keyword(s):  
Laser Processing ◽  
Laser Energy ◽  
High Spatial Frequency ◽  
Laser Pulses ◽  
Successful Implementation ◽  
Experimental Conditions ◽  
Sensing Applications ◽  
Direct Laser ◽  
Fs Laser ◽  
One Step

Direct laser processing of various materials with nano- and femtosecond (fs) laser pulses is known to be a facile and inexpensive technology for fabrication of various surface morphologies. Since ultrafast deposition of the laser energy to target material typically creates unique experimental conditions with extremely high pressure and temperature, we hypothesized that carrying out this process in anhydrous non-oxidizing environment containing functionalizing agent (fluorophore with vinyl functional group) will allow one-step fabrication and subsequent functionalization of the surface of high-n material. In this paper, we demonstrate successful implementation of this idea by fabricating high-spatial-frequency laser-induced periodic surface structures (LIPSS) via direct fs-pulse ablation of bulk crystalline Si wafer immersed in solution of N-vinylcarbazole in toluene. Laser processing with linearly polarized fs-laser pulses was found to produce LIPSS with a characteristic period around 100 nm functionalized with N-vinylcarbazole molecules via photo-activated hydrosililation reaction. The unique LIPSS with hierarchical roughness and remarkable light trapping performance functionalized with sensory fluorophore show high sensitivity due to implementation of surface enhanced fluorescence effect. By using N-vinylcarbazole as functionalizing agent we demonstrate one-step fabrication of high-performance sensor for detecting nitrobenzene in water with a detection limit of 40 nM.

Frames of Reference for Hand Orientation

1995 ◽  
Vol 7 (2) ◽  
pp. 182-195 ◽  
Author(s):  
Martha Flanders ◽  
John F. Soechting
Keyword(s):  
Reference Frame ◽  
Neural Control ◽  
Human Subjects ◽  
Object Orientation ◽  
Frame Of Reference ◽  
Object Location ◽  
Frames Of Reference ◽  
Spatial Reference ◽  
Hand Orientation ◽  
Spatial Reference Frame

In reaching and grasping movements, information about object location and object orientation is used to specify the appropriate proximal arm posture and the appropriate positions for the wrist and fingers. Since object orientation is ideally defined in a frame of reference fixed in space, this study tested whether the neural control of hand orientation is also best described as being in this spatial reference frame. With the proximal arm in various postures, human subjects used a handheld rod to approximate verbally defined spatial orientations. Subjects did quite well at indicating spatial vertical and spatial horizontal but made consistent errors in estimating 45° spatial slants. The errors were related to the proximal arm posture in a way that indicated that oblique hand orientations may be specified as a compromise between a reference frame fixed in space and a reference frame fixed to the arm. In another experiment, where subjects were explicitly requested to use a reference frame fixed to the arm, the performance was consistently biased toward a spatial reference frame. The results suggest that reaching and grasping movements may be implemented as an amalgam of two frames of reference, both neurally and behaviorally.

scholarly journals Local field potentials allow accurate decoding of muscle activity

2012 ◽  
Vol 108 (1) ◽  
pp. 18-24 ◽  
Author(s):  
Robert D. Flint ◽  
Christian Ethier ◽  
Emily R. Oby ◽  
Lee E. Miller ◽  
Marc W. Slutzky
Keyword(s):  
Upper Limb ◽  
Local Field ◽  
Muscle Activity ◽  
Primary Motor Cortex ◽  
Target Location ◽  
Local Field Potentials ◽  
Field Potentials ◽  
Reach To Grasp ◽  
Significant Information ◽  
Complex Movement

Local field potentials (LFPs) in primary motor cortex include significant information about reach target location and upper limb movement kinematics. Some evidence suggests that they may be a more robust, longer-lasting signal than action potentials (spikes). Here we assess whether LFPs can also be used to decode upper limb muscle activity, a complex movement-related signal. We record electromyograms from both proximal and distal upper limb muscles from monkeys performing a variety of reach-to-grasp and isometric wrist force tasks. We show that LFPs can be used to decode activity from both proximal and distal muscles with performance rivaling that of spikes. Thus, motor cortical LFPs include information about more aspects of movement than has been previously demonstrated. This provides further evidence suggesting that LFPs could provide a highly informative, long-lasting signal source for neural prostheses.

The role of sodium ions in ATP formation by the sodium pump

1977 ◽  
Vol 198 (1131) ◽  
pp. 109-128 ◽  
Keyword(s):  
Driving Force ◽  
Transfer Reaction ◽  
Sodium Pump ◽  
Atp Synthesis ◽  
Rabbit Kidney ◽  
Experimental Conditions ◽  
Atp Formation ◽  
One Step ◽  
Na Ions

A study has been made to characterize ATP synthesis from ADP and P 1 by the sodium pump with membranes isolated from rabbit kidney. Incorporation of 32 P 1 into ATP was measured. ATP was not formed in a one-step reaction. Synthesis was dependent upon two separate incuba­tions in which incorporation of P 1 into phosphoprotein was followed by transfer of phosphate to ADP. The experimental conditions for the first reaction were different from those for the second (phosphate transfer) reaction. The latter took place only when a high Na concentration (at least 0.5 M) was added. ATP formation was prevented by both K and ouabain. The sequence of reactions could be repeated after washing to remove Na ions, indicating that the driving force for the reactions could be regenerated. The dissipation of ionic gradients was not involved because the Lubrol-solubilized pump was also able to synthesize ATP. It was concluded that the energy for ATP synthesis was derived from specific and reversible interactions of Na ions with the pump. The reactions for ATP synthesis by the sodium pump have been summarized in the form of a cycle.

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