Interlimb Transfer after Adaptation to Visual Displacement: Patterns Predicted from the Functional Closeness of Limb Neural Control Centres

Two experiments were designed to determine whether interlimb transfer of prism adaptation follows a pattern predicted by the functional closeness of limb control centres. Subjects were adapted to a lateral displacing prism with their right arm in conditions known to facilitate interlimb transfer. Negative aftereffect measures of target-pointing shift were taken for all limbs. If transfer to the unadapted limbs is primarily the result of some sort of visual change, scores for those limbs should not differ. However, if the functional cerebral closeness of limb control centres is a factor, the greatest shift should be evidenced in the homologous contralateral limb (left arm), followed by the ipsilateral limb (right leg), with the least shift to the diagonally opposite limb (left leg). No differences in shift among the three unadapted limbs was found in the two experiments.

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Speculations on a Model of Prism Adaptation

Perception ◽

10.1068/p030451 ◽

1974 ◽

Vol 3 (4) ◽

pp. 451-460 ◽

Cited By ~ 18

Author(s):

R B Welch

Keyword(s):

Motor Learning ◽

Corrective Feedback ◽

Prism Adaptation ◽

Prism Exposure ◽

Visual Shift ◽

Proprioceptive Shift ◽

Negative Aftereffect ◽

Corrective Response

Arguments and evidence are presented that prism adaptation results in a third end state in addition to the ‘traditional’ components of ‘proprioceptive shift’ and ‘visual shift’. That is, under certain conditions (most importantly, ones involving error-corrective feedback), exposure to prism-displaced vision induces a motor-learning component, referred to here as an ‘assimilated corrective response’. Thus the postexposure error in target pointing, the ‘negative aftereffect’, is postulated to be the algebraic sum of proprioceptive shift, visual shift, and an assimilated corrective response—at least in certain situations. Support for the existence of this third component as a form of learning is seen in the fact that it occurs primarily when prism exposure involves target-pointing experience, and that it is apparently subject to the effects of some ‘learning variables’.

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Primacy of the negative aftereffect over positive adaptation in prism adaptation with newly hatched chicks

Developmental Psychobiology ◽

10.1002/dev.420020111 ◽

1969 ◽

Vol 2 (1) ◽

pp. 43-53 ◽

Cited By ~ 9

Author(s):

Patrick J. Rossi

Keyword(s):

Prism Adaptation ◽

Positive Adaptation ◽

Negative Aftereffect

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Maximal intermittent contractions of the first dorsal interosseous inhibits voluntary activation of the contralateral homologous muscle

Journal of Neurophysiology ◽

10.1152/jn.00367.2016 ◽

2016 ◽

Vol 116 (5) ◽

pp. 2272-2280 ◽

Cited By ~ 5

Author(s):

Justin J. Kavanagh ◽

Matthew R. Feldman ◽

Michael J. Simmonds

Keyword(s):

Index Finger ◽

Motor Evoked Potentials ◽

Motor Evoked Potential ◽

Voluntary Activation ◽

Reflex Activity ◽

First Dorsal Interosseous ◽

Contralateral Limb ◽

The Central Nervous System ◽

Opposite Limb ◽

Intermittent Contractions

The aim of this study was to investigate how maximal intermittent contractions for a hand muscle influence cortical and reflex activity, as well as the ability to voluntarily activate the homologous muscle in the opposite limb. Twelve healthy subjects (age 24 ± 3 yr, all right-hand dominant) performed maximal contractions of the dominant limb first dorsal interosseous (FDI), and activity of the contralateral FDI was examined in a series of experiments. Index finger abduction force, FDI electromyography (EMG), motor evoked potentials, and heteronomous reflexes were obtained from the contralateral limb during brief, nonfatiguing contractions. The same measures, as well as the ability to voluntarily activate the contralateral FDI, were then assessed in an extended intermittent contraction protocol that elicited fatigue. Brief contractions under nonfatigued conditions increased index finger abduction force, FDI EMG, and motor evoked potential amplitude of the contralateral limb. However, when intermittent maximal contractions were continued until fatigue, there was an inability to produce maximal force with the contralateral limb (∼30%), which was coupled to a decrease in the level of voluntary activation (∼20%). These declines were present without changes in reflex activity and regardless of whether cortical or motor point stimulation was used to assess voluntary activation. It is concluded that performing maximal intermittent contractions with a single limb causes an inability of the central nervous system to maximally drive the homologous muscle of the contralateral limb. This is, in part, mediated by mechanisms that involve the motor cortex ipsilateral to the contracting limb.

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