Notes toward a motor theory of visual egocentric localization.

1955 ◽  
Vol 62 (5) ◽  
pp. 391-400 ◽  
Author(s):  
Jan H. Bruell ◽  
George W. Albee
Keyword(s):  
Motor Theory ◽  
Egocentric Localization

Motor theory modulated by task load: strategies of phonological processing in frontal aphasia revealed by tDCS over the LIFG

2019 ◽  
Author(s):  
Lílian Rodrigues de Almeida ◽  
Paul A. Pope ◽  
Peter Hansen
Keyword(s):  
Speech Perception ◽  
Speech Production ◽  
Phonological Processing ◽  
Inferior Frontal Gyrus ◽  
Dorsal Stream ◽  
Superior Temporal Gyrus ◽  
Motor Theory ◽  
Task Load ◽  
Cathodal Tdcs ◽  
The Individual

In our previous studies we supported the claim that the motor theory is modulated by task load. Motoric participation in phonological processing increases from speech perception to speech production, with the endpoints of the dorsal stream having changing and complementary weightings for processing: the left inferior frontal gyrus (LIFG) being increasingly relevant and the left superior temporal gyrus (LSTG) being decreasingly relevant. Our previous results for neurostimulation of the LIFG support this model. In this study we investigated whether our claim that the motor theory is modulated by task load holds in (frontal) aphasia. Person(s) with aphasia (PWA) after stroke typically have damage on brain areas responsible for phonological processing. They may present variable patterns of recovery and, consequently, variable strategies of phonological processing. Here these strategies were investigated in two PWA with simultaneous fMRI and tDCS of the LIFG during speech perception and speech production tasks. Anodal tDCS excitation and cathodal tDCS inhibition should increase with the relevance of the target for the task. Cathodal tDCS over a target of low relevance could also induce compensation by the remaining nodes. Responses of PWA to tDCS would further depend on their pattern of recovery. Responses would depend on the responsiveness of the perilesional area, and could be weaker than in controls due to an overall hypoactivation of the cortex. Results suggest that the analysis of motor codes for articulation during phonological processing remains in frontal aphasia and that tDCS is a promising diagnostic tool to investigate the individual processing strategies.

scholarly journals Concerning emotive phenomena. —Part III. The influence of drugs upon the electrical conductivity of the palm of the hand

1919 ◽  
Vol 91 (635) ◽  
pp. 32-40 ◽  
Keyword(s):  
Electrical Conductivity ◽  
Healthy Subject ◽  
Electrical Resistance ◽  
Single Observation ◽  
Motor Theory ◽  
Few Data ◽  
Palm Of The Hand

I possess comparatively few data concerning the action of drugs upon “Emotivity” or, to put it more specifically, upon the electrical resistance of the palm of the hand. Except as regards atropine, with which I have made many observations to test the sudo-motor theory of the reaction, I find in my notes only one satisfactory observation upon each of the following drugs: alcohol, chloroform, morphia, which I will transcribe. Obviously, a single observation of any drug can give only a single facet of its action under the particular conditions of experiment. It will, however, be clear that the results have, in each instance, been such as might be anticipated on general principles with one notable exception, viz., atropine. Experiment 1: Alcohol . —A healthy subject, F. G., aged 30, with an initial hand conductance = 17 γ ( = 60, 000 ohms) gave emotive reactions = 37 γ to the threat of a burn (match struck) and 2 γ to an actual slight burn, immediately before and immediately after the ingestion of 50 c. c. of whisky. The conductance remained unaltered at 17 γ .

scholarly journals What happens to the motor theory of perception when the motor system is damaged?

2013 ◽  
Vol 5 (2-3) ◽  
pp. 225-238 ◽  
Author(s):  
Alena Stasenko ◽  
Frank E. Garcea ◽  
Bradford Z. Mahon
Keyword(s):  
Speech Perception ◽  
Action Recognition ◽  
Motor System ◽  
Motor Impairments ◽  
Motor Theory ◽  
Input And Output ◽  
Motor Information ◽  
Neuropsychological Evidence ◽  
Motor Representations ◽  
Speech Motor

AbstractMotor theories of perception posit that motor information is necessary for successful recognition of actions. Perhaps the most well known of this class of proposals is the motor theory of speech perception, which argues that speech recognition is fundamentally a process of identifying the articulatory gestures (i.e. motor representations) that were used to produce the speech signal. Here we review neuropsychological evidence from patients with damage to the motor system, in the context of motor theories of perception applied to both manual actions and speech. Motor theories of perception predict that patients with motor impairments will have impairments for action recognition. Contrary to that prediction, the available neuropsychological evidence indicates that recognition can be spared despite profound impairments to production. These data falsify strong forms of the motor theory of perception, and frame new questions about the dynamical interactions that govern how information is exchanged between input and output systems.

scholarly journals The Perception-for-Action-Control Theory (PACT): A perceptuo-motor theory of speech perception

2012 ◽  
Vol 25 (5) ◽  
pp. 336-354 ◽  
Author(s):  
Jean-Luc Schwartz ◽  
Anahita Basirat ◽  
Lucie Ménard ◽  
Marc Sato
Keyword(s):  
Speech Perception ◽  
Control Theory ◽  
Action Control ◽  
Motor Theory

Isotropic visual field effect on spatial orientation and egocentric localization

1998 ◽  
Vol 11 (3) ◽  
pp. 261-278 ◽  
Author(s):  
Theophile Ohlmann ◽  
Didier Poquin ◽  
Pierre Alain Barraud
Keyword(s):  
Visual Field ◽  
Spatial Orientation ◽  
Field Effect ◽  
Visual Field Effect ◽  
Egocentric Localization

Spatial localization in cats reared with strabismus

1980 ◽  
Vol 43 (3) ◽  
pp. 792-806 ◽  
Author(s):  
C. R. Olson
Keyword(s):  
Striate Cortex ◽  
Behavioral Flexibility ◽  
Rectus Muscle ◽  
The Body ◽  
Neural Function ◽  
Repeated Testing ◽  
Visual Guidance ◽  
Normal Environment ◽  
Eyes Open ◽  
Egocentric Localization

1. The capacity for judging the location of an object relative to the body (egocentric localization) was assessed in cats by measuring the landing position attained when the cat jumped toward a platform viewed from a known distance. 2. Normal cats and kittens land at center of the platform when using one eye or both. In contrast, nine animals tested immediately after tenotomy of the medial rectus muscle of one eye all landed consistently off-center when using the operated eye. The direction of the error was predictable from the assumption that the cat was unaware of the eye's deviation from its natural position. Thus, proprioceptive reafference is not capable, under these conditions, of supporting an accurate awareness of eye position. 3. After initial testing, all cats were maintained in a normal environment with both eyes open and were tested intermittently. Jumps guided by the deviated eye became accurate over a period of weeks in kittens younger than 4 mo. In contrast, behavioral adjustment in older kittens required many months. An adult cat displayed almost no adjustment over a period of 9 mo. 4. Five additional kittens were first tested several months after the onset of strabismus. These animals manifested accurate use of the operated eye from the first trial onward. Therefore, acquisition of accurate use of the deviated eye is not dependent on repeated testing. 5. Two kittens subjected to early exodeviation of one eye displayed a reduced capacity for adjustment when subjected to late exodeviation of the second eye. Thus, changes in neural function resulting from early strabismus (for instance, the loss of binocular connectivity in striate cortex) do not produce persistent behavioral flexibility. 6. In two strabismic kittens with a fully developed compensatory adjustment of monocular egocentric localization, the capacity for judging the relative location of two objects viewed simultaneously through separate eyes was assessed through use of a two-choice visual discrimination paradigm. One animal made predictable systematic errors, while the other exhibited correct judgments. Thus, it appears that a compensatory shift of retinal correspondence may occur in some strabismic kittens, but that such a change is not necessary for accurate use of the deviated eye in monocular visual guidance. 7. A number of observations are described that tend to indicate that cats reared with strabismus continue to use both the deviated and the nondeviated eye for visual guidance under binocular viewing conditions, unlike many human strabismics.

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