Congenital mirror movements: a clue to understanding bimanual motor control

AbstractIn human, execution of unimanual movements requires lateralized activation of the primary motor cortex, which then transmits the motor command to the contralateral hand through the crossed corticospinal tract (CST). Mutations in NETRIN-1 alter motor control lateralization, leading to congenital mirror movements. To address the role of midline Netrin-1 on CST development and subsequent motor control, we analyzed the morphological and functional consequences of floor-plate Netrin-1 depletion in conditional knock-out mice (Shh::cre;Ntn1lox/lox mice).Here, we show that depletion of floor plate Netrin-1 critically disrupts midline crossing of the CST, whereas the other commissural systems are mostly preserved. The CST defect results in abnormal but functional ipsilateral projections, and is associated with abnormal symmetric movements. Therefore, our study reveals a new role for Netrin-1 in CST development. It also describes a unique mouse model recapitulating characteristics of human congenital mirror movements, through abnormal CST decussation.

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Ipsilateral Motor Control Without Mirror Movements?

Neuropediatrics ◽

10.1055/s-0032-1307060 ◽

2012 ◽

Vol 43 (02) ◽

Cited By ~ 2

Author(s):

M Staudt ◽

T Pieper ◽

C Adler ◽

M Hessenauer ◽

M Kudernatsch ◽

...

Keyword(s):

Motor Control ◽

Mirror Movements

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Syntax, Stress Response, and Speech Motor Control

Perspectives on Fluency and Fluency Disorders ◽

10.1044/ffd17.2.25 ◽

2007 ◽

Vol 17 (2) ◽

pp. 25-26

Author(s):

Jennifer Kleinow

Keyword(s):

Motor Control ◽

Stress Response ◽

Speech Motor Control ◽

Speech Motor

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Do Sentence Length and Syntactic Complexity Influence Speech Motor Control?

ASHA Leader ◽

10.1044/leader.rib3.18072013.33 ◽

2013 ◽

Vol 18 (7) ◽

pp. 33-34

Keyword(s):

Motor Control ◽

Sentence Length ◽

Speech Motor Control ◽

Syntactic Complexity ◽

Speech Motor

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Physiologic Studies Provide New Perspectives on Early Speech Development

Perspectives on Speech Science and Orofacial Disorders ◽

10.1044/ssod20.2.29 ◽

2010 ◽

Vol 20 (2) ◽

pp. 29-36

Author(s):

Erin M. Wilson ◽

Ignatius S. B. Nip

Keyword(s):

Motor Control ◽

Motor Development ◽

Motion Tracking ◽

Speech Development ◽

Speech Motor Control ◽

Therapeutic Approaches ◽

Facial Motion ◽

Disordered Speech ◽

Speech Motor ◽

Physiologic Data

Abstract Although certain speech development milestones are readily observable, the developmental course of speech motor control is largely unknown. However, recent advances in facial motion tracking systems have been used to investigate articulator movements in children and the findings from these studies are being used to further our understanding of the physiologic basis of typical and disordered speech development. Physiologic work has revealed that the emergence of speech is highly dependent on the lack of flexibility in the early oromotor system. It also has been determined that the progression of speech motor development is non-linear, a finding that has motivated researchers to investigate how variables such as oromotor control, cognition, and linguistic factors affect speech development in the form of catalysts and constraints. Physiologic data are also being used to determine if non-speech oromotor behaviors play a role in the development of speech. This improved understanding of the physiology underlying speech, as well as the factors influencing its progression, helps inform our understanding of speech motor control in children with disordered speech and provide a framework for theory-driven therapeutic approaches to treatment.

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