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Di Nardo F, Manara R, Canna A, Trojsi F, Velletrani G, Sinisi AA, Cirillo M, Tedeschi G, Esposito F. Dynamic spectral signatures of mirror movements in the sensorimotor functional connectivity network of patients with Kallmann syndrome. Front Neurosci 2022; 16:971809. [PMID: 36117618 PMCID: PMC9477102 DOI: 10.3389/fnins.2022.971809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 08/08/2022] [Indexed: 11/16/2022] Open
Abstract
In Kallmann syndrome (KS), the peculiar phenomenon of bimanual synkinesis or mirror movement (MM) has been associated with a spectral shift, from lower to higher frequencies, of the resting-state fMRI signal of the large-scale sensorimotor brain network (SMN). To possibly determine whether a similar frequency specificity exists across different functional connectivity SMN states, and to capture spontaneous transitions between them, we investigated the dynamic spectral changes of the SMN functional connectivity in KS patients with and without MM symptom. Brain MRI data were acquired at 3 Tesla in 39 KS patients (32 without MM, KSMM-, seven with MM, KSMM+) and 26 age- and sex-matched healthy control (HC) individuals. The imaging protocol included 20-min rs-fMRI scans enabling detailed spectro-temporal analyses of large-scale functional connectivity brain networks. Group independent component analysis was used to extract the SMN. A sliding window approach was used to extract the dynamic spectral power of the SMN functional connectivity within the canonical physiological frequency range of slow rs-fMRI signal fluctuations (0.01–0.25 Hz). K-means clustering was used to determine (and count) the most recurrent dynamic states of the SMN and detect the number of transitions between them. Two most recurrent states were identified, for which the spectral power peaked at a relatively lower (state 1) and higher (state 2) frequency. Compared to KS patients without MM and HC subjects, the SMN of KS patients with MM displayed significantly larger spectral power changes in the slow 3 canonical sub-band (0.073–0.198 Hz) and significantly fewer transitions between state 1 (less recurrent) and state 2 (more recurrent). These findings demonstrate that the presence of MM in KS patients is associated with reduced spontaneous transitions of the SMN between dynamic functional connectivity states and a higher recurrence and an increased spectral power change of the high-frequency state. These results provide novel information about the large-scale brain functional dynamics that could help to understand the pathologic mechanisms of bimanual synkinesis in KS syndrome and, potentially, other neurological disorders where MM may also occur.
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Affiliation(s)
- Federica Di Nardo
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli,”Naples, Italy
| | - Renzo Manara
- Department of Neuroscience, University of Padova, Padova, Italy
| | - Antonietta Canna
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli,”Naples, Italy
| | - Francesca Trojsi
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli,”Naples, Italy
| | - Gianluca Velletrani
- Department of Medicine, Surgery and Dentistry, University of Salerno, Salerno, Italy
| | - Antonio Agostino Sinisi
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli,”Naples, Italy
| | - Mario Cirillo
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli,”Naples, Italy
| | - Gioacchino Tedeschi
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli,”Naples, Italy
| | - Fabrizio Esposito
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli,”Naples, Italy
- *Correspondence: Fabrizio Esposito,
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Jo Y, Javidialsaadi M, Wang J. Facilitative effects of use-dependent learning on interlimb transfer of visuomotor adaptation in a person with congenital mirror movements. Hum Mov Sci 2022; 84:102973. [PMID: 35763973 DOI: 10.1016/j.humov.2022.102973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 06/15/2022] [Accepted: 06/21/2022] [Indexed: 11/20/2022]
Abstract
It has been shown that use-dependent learning can facilitate interlimb transfer of motor learning in neurologically intact individuals. However, it is unknown whether it can also facilitate interlimb transfer in individuals with neurological impairment. In this case study, we examined the effect of use-dependent learning on interlimb transfer of visuomotor adaptation in a person with congenital mirror movements, DB, who showed no interlimb transfer in our previous studies (Bao, Morgan, Lei, & Wang, 2020; Javidialsaadi, & Wang, 2021). DB first performed reaching movements with the right arm repeatedly while adapting to a visuomotor rotation condition with the left arm (training session), and then adapted to the same rotation condition with the right arm (transfer session). DB's right arm performance in the transfer session was significantly better than that observed in our previous studies, indicating interlimb transfer of visuomotor adaptation. The percentage of transfer was over 90%, which is similar to that observed in healthy young adults previously. These findings suggest that interlimb transfer of visuomotor adaptation can occur by involving model-based learning, which is effector independent, and/or use-dependent (or model-free) learning, which is effector specific; and also that the relative contribution of use-dependent learning to interlimb transfer of visuomotor adaptation can be as large as that of model-based learning.
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Affiliation(s)
- Yeongsin Jo
- Department of Kinesiology, University of Wisconsin, Milwaukee, WI 53201, USA
| | - Mousa Javidialsaadi
- Department of Kinesiology, University of Wisconsin, Milwaukee, WI 53201, USA
| | - Jinsung Wang
- Department of Kinesiology, University of Wisconsin, Milwaukee, WI 53201, USA.
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Filippopulos FM, Brem C, Seelos K, Köglsperger T, Sonnenfeld S, Kellert L, Vollmar C. Uncrossed corticospinal tract in health and genetic disorders: Review, case report, and clinical implications. Eur J Neurol 2021; 28:2804-2811. [PMID: 33949047 DOI: 10.1111/ene.14897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE Crossing pathologies of the corticospinal tract (CST) are rare and often associated with genetic disorders. However, they can be present in healthy humans and lead to ipsilateral motor deficits when a lesion to motor areas occurs. Here, we review historical and current literature of CST crossing pathologies and present a rare case of asymmetric crossing of the CST. METHODS Description of the case and systematic review of the literature were based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The PubMed database was searched for peer-reviewed articles in English since 1950. All articles on ipsilateral stroke, uncrossed CST, and associated neurologic disorders were screened. Furthermore, a literature review between the years 1850 and 1980 including articles in other languages, books, opinions, and case studies was conducted. RESULTS Only a few descriptions of CST crossing pathologies exist in healthy humans, whereas they seem to be more common in genetic disorders such as horizontal gaze palsy with progressive scoliosis or congenital mirror movements. Our patient presented with aphasia and left-sided hemiparesis. Computed tomographic (CT) scan revealed a perfusion deficit in the left middle cerebral artery territory, which was confirmed by diffusion-weighted magnetic resonance imaging (MRI), so that thrombolysis was administered. Diffusion tensor imaging with fibre tracking revealed an asymmetric CST crossing. CONCLUSIONS The knowledge of CST crossing pathologies is essential if a motor deficit occurs ipsilateral to the lesion side. An ipsilateral deficit should not lead to exclusion or delay of therapeutic options in patients with suspected stroke. Here, a combined evaluation of CT perfusion imaging and MRI diffusion imaging may be of advantage.
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Affiliation(s)
| | - Christian Brem
- Institute of Neuroradiology, University Hospital of the LMU Munich, Munich, Germany
| | - Klaus Seelos
- Institute of Neuroradiology, University Hospital of the LMU Munich, Munich, Germany
| | - Thomas Köglsperger
- Department of Neurology, University Hospital of the LMU Munich, Munich, Germany
| | - Stefan Sonnenfeld
- Department of Neurology, University Hospital of the LMU Munich, Munich, Germany
| | - Lars Kellert
- Department of Neurology, University Hospital of the LMU Munich, Munich, Germany
| | - Christian Vollmar
- Department of Neurology, University Hospital of the LMU Munich, Munich, Germany.,Institute of Neuroradiology, University Hospital of the LMU Munich, Munich, Germany
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4
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Lack of interlimb transfer following visuomotor adaptation in a person with congenital mirror movements. Neuropsychologia 2020; 136:107265. [DOI: 10.1016/j.neuropsychologia.2019.107265] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 11/07/2019] [Accepted: 11/12/2019] [Indexed: 01/05/2023]
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Demirayak P, Onat OE, Gevrekci AÖ, Gülsüner S, Uysal H, Bilgen RS, Doerschner K, Özçelik TS, Boyacı H. Abnormal subcortical activity in congenital mirror movement disorder with RAD51 mutation. ACTA ACUST UNITED AC 2018; 24:392-401. [PMID: 30406765 DOI: 10.5152/dir.2018.18096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
PURPOSE Congenital mirror movement disorder (CMMD) is characterized by unintended, nonsuppressible, homologous mirroring activity contralateral to the movement on the intended side of the body. In healthy controls, unilateral movements are accompanied with predominantly contralateral cortical activity, whereas in CMMD, in line with the abnormal behavior, bilateral cortical activity is observed for unilateral motor tasks. However, task-related activities in subcortical structures, which are known to play critical roles in motor actions, have not been investigated in CMMD previously. METHODS We investigated the functional activation patterns of the motor components in CMMD patients. By using linkage analysis and exome sequencing, common mutations were revealed in seven affected individuals from the same family. Next, using functional magnetic resonance imaging (fMRI) we investigated cortical and subcortical activity during manual motor actions in two right-handed affected brothers and sex, age, education, and socioeconomically matched healthy individuals. RESULTS Genetic analyses revealed heterozygous RAD51 c.401C>T mutation which cosegregated with the phenotype in two affected members of the family. Consistent with previous literature, our fMRI results on these two affected individuals showed that mirror movements were closely related to abnormal cortical activity in M1 and SMA during unimanual movements. Furthermore, we have found previously unknown abnormal task-related activity in subcortical structures. Specifically, we have found increased and bilateral activity during unimanual movements in thalamus, striatum, and globus pallidus in CMMD patients. CONCLUSION These findings reveal further neural correlates of CMMD, and may guide our understanding of the critical roles of subcortical structures for unimanual movements in healthy individuals.
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Affiliation(s)
- Pınar Demirayak
- Neuroscience Graduate Program, Bilkent University; A.S. Brain Research Center and National Magnetic Resonance Research Center, Bilkent University, Ankara, Turkey
| | - Onur Emre Onat
- Department of Molecular Biology and Genetics, Bilkent University, Ankara, Turkey
| | | | - Süleyman Gülsüner
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Hilmi Uysal
- Department of Neurology, Akdeniz University School of Medicine, Antalya, Turkey
| | - Rengin S Bilgen
- Department of Neurology, Bezmialem University School of Medicine, İstanbul, Turkey
| | - Katja Doerschner
- Neuroscience Graduate Program, A.S. Brain Research Center and National Magnetic Resonance Research Center and Psychology, Bilkent University, Ankara, Turkey; Department of Psychology, JL Giessen University, Giessen, Germany
| | - Tayfun S Özçelik
- Department of Molecular Biology and Genetics, Bilkent University, Ankara, Turkey
| | - Hüseyin Boyacı
- Neuroscience Graduate Program, A.S. Brain Research Center and National Magnetic Resonance Research Center and Psychology, Bilkent University, Ankara, Turkey; Department of Psychology, JL Giessen University, Giessen, Germany
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Bierhals T, Korenke GC, Baethmann M, Marín LL, Staudt M, Kutsche K. Novel DCC variants in congenital mirror movements and evaluation of disease-associated missense variants. Eur J Med Genet 2018; 61:329-334. [DOI: 10.1016/j.ejmg.2018.01.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/04/2018] [Accepted: 01/19/2018] [Indexed: 12/15/2022]
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7
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Akinola OB, Gabriel MO. Neuroanatomical and molecular correlates of cognitive and behavioural outcomes in hypogonadal males. Metab Brain Dis 2018; 33:491-505. [PMID: 29230619 DOI: 10.1007/s11011-017-0163-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 11/28/2017] [Indexed: 12/18/2022]
Abstract
Robust epidemiological, clinical and laboratory evidence supports emerging roles for the sex steroids in such domains as neurodevelopment, behaviour, learning and cognition. Regions of the mammalian brain that are involved in cognitive development and memory do not only express the classical nuclear androgen receptor, but also the non-genomic membrane receptor, which is a G protein-coupled receptor that mediates some rapid effects of the androgens on neurogenesis and synaptic plasticity. Under physiological conditions, hippocampal neurons do express the enzyme aromatase, and therefore actively aromatize testosterone to oestradiol. Although glial expression of the aromatase enzyme is minimal, increased expression following injury suggests a role for sex steroids in neuroprotection. It is therefore plausible to deduce that low levels of circulating androgens in males would perturb neuronal functions in relation to cognition and memory, as well as neural repair following injury. The present review is an overview of some roles of the sex steroids on cognitive function in males, and the neuroanatomical and molecular underpinnings of some behavioural and cognitive deficits characteristic of such genetic disorders noted for low androgen levels, including Klinefelter syndrome, Bardet-Biedl syndrome, Kallman syndrome and Prader-Willi syndrome. Recent literature in relation to some behavioural and cognitive changes secondary to surgical and pharmacological castration are also appraised.
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Affiliation(s)
- O B Akinola
- Division of Endocrinology, Department of Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Nigeria.
| | - M O Gabriel
- Division of Endocrinology, Department of Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, University of Ilorin, Ilorin, Nigeria
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8
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Manara R, Di Nardo F, Salvalaggio A, Sinisi AA, Bonanni G, Palumbo V, Cantone E, Brunetti A, Di Salle F, D'errico A, Elefante A, Esposito F. Spectral signatures of mirror movements in the sensori-motor connectivity in kallmann syndrome. Hum Brain Mapp 2017; 39:42-53. [PMID: 28963812 DOI: 10.1002/hbm.23806] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 07/16/2017] [Accepted: 08/29/2017] [Indexed: 11/08/2022] Open
Abstract
Mirror movements (MM) might be observed in congenital and acquired neurodegenerative conditions but their anatomic-functional underpinnings are still largely elusive. This study investigated the spectral changes of resting-state functional connectivity in Kallmann Syndrome (hypogonadotropic hypogonadism with hypo/anosmia with or without congenital MM) searching for insights into the phenomenon of MM. Forty-four Kallmann syndrome patients (21 with MM) and 24 healthy control subjects underwent task (finger tapping) and resting-state functional MRI. The spatial pattern of task-related activations was used to mask regions and select putative motor networks in a spatially independent component analysis of resting-state signals. For each resting-state independent component time-course power spectrum, we extracted the relative contribution of four separate bands: slow-5 (0.01-0.027 Hz), slow-4 (0.027-0.073 Hz), slow-3 (0.073-0.198 Hz), slow-2 (0.198-0.25 Hz), and analyzed the variance between groups. For the sensorimotor network, the analysis revealed a significant group by frequency interaction (P = 0.002) pointing to a frequency shift in the spectral content among subgroups with lower slow-5 band and higher slow-3 band contribution in Kallmann patients with MM versus controls (P = 0.028) and with lower slow-5 band contribution between patients with and without MM (P = 0.057). In specific regions, as obtained from hand motor activation task analysis, spectral analyses demonstrated a lower slow-5 band contribution in Kallmann patients with MM versus both controls and patients without MM (P < 0.05). In Kallmann syndrome, the peculiar phenomenon of bimanual synkinesis is associated at rest with regionally and spectrally selective functional connectivity changes pointing to a distinctive cortical and subcortical functional reorganization. Hum Brain Mapp 39:42-53, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Renzo Manara
- Department of Medicine, Surgery and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| | - Federica Di Nardo
- Department of Medical, Surgical, neurological, Metabolic and aging sciences, Second University of Napoli, Italy
| | | | - Antonio Agostino Sinisi
- Department of Medical, Surgical, neurological, Metabolic and aging sciences, Second University of Napoli, Italy
| | | | | | - Elena Cantone
- Department of Neuroscience, ENT section, Università Federico II, Italy
| | - Arturo Brunetti
- Dipartimento di Scienze Biomediche Avanzate, Università Federico II, Napoli, Italy
| | - Francesco Di Salle
- Department of Medicine, Surgery and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| | - Arianna D'errico
- Dipartimento di Scienze Biomediche Avanzate, Università Federico II, Napoli, Italy
| | - Andrea Elefante
- Dipartimento di Scienze Biomediche Avanzate, Università Federico II, Napoli, Italy
| | - Fabrizio Esposito
- Department of Medicine, Surgery and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
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9
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Congenital mirror movements in a patient with alpha-dystroglycanopathy due to a novel POMK mutation. Neuromuscul Disord 2017; 27:239-242. [DOI: 10.1016/j.nmd.2016.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 12/05/2016] [Accepted: 12/12/2016] [Indexed: 11/21/2022]
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10
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Lack of decussation of pyramids in Kallmann syndrome presenting with mirror movements. J Neurol Sci 2017; 372:220-222. [DOI: 10.1016/j.jns.2016.11.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 11/07/2016] [Accepted: 11/21/2016] [Indexed: 11/19/2022]
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11
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Norton J, Sawicka K. The significance of hand movement mirroring in cerebral palsy. Dev Med Child Neurol 2016; 58:655-6. [PMID: 26786176 DOI: 10.1111/dmcn.13029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Jonathan Norton
- Department of Surgery, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Katherine Sawicka
- Department of Surgery, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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12
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Welniarz Q, Dusart I, Gallea C, Roze E. One hand clapping: lateralization of motor control. Front Neuroanat 2015; 9:75. [PMID: 26082690 PMCID: PMC4451425 DOI: 10.3389/fnana.2015.00075] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/17/2015] [Indexed: 12/20/2022] Open
Abstract
Lateralization of motor control refers to the ability to produce pure unilateral or asymmetric movements. It is required for a variety of coordinated activities, including skilled bimanual tasks and locomotion. Here we discuss the neuroanatomical substrates and pathophysiological underpinnings of lateralized motor outputs. Significant breakthroughs have been made in the past few years by studying the two known conditions characterized by the inability to properly produce unilateral or asymmetric movements, namely human patients with congenital “mirror movements” and model rodents with a “hopping gait”. Whereas mirror movements are associated with altered interhemispheric connectivity and abnormal corticospinal projections, abnormal spinal cord interneurons trajectory is responsible for the “hopping gait”. Proper commissural axon guidance is a critical requirement for these mechanisms. Interestingly, the analysis of these two conditions reveals that the production of asymmetric movements involves similar anatomical and functional requirements but in two different structures: (i) lateralized activation of the brain or spinal cord through contralateral silencing by cross-midline inhibition; and (ii) unilateral transmission of this activation, resulting in lateralized motor output.
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Affiliation(s)
- Quentin Welniarz
- Neuroscience Paris Seine, CNRS UMR8246, Inserm U1130, Sorbonne Universités, UPMC UM119 Paris, France ; Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC UMR S1127, Institut du Cerveau et de la Moelle épinière, ICM Paris, France
| | - Isabelle Dusart
- Neuroscience Paris Seine, CNRS UMR8246, Inserm U1130, Sorbonne Universités, UPMC UM119 Paris, France
| | - Cécile Gallea
- Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC UMR S1127, Institut du Cerveau et de la Moelle épinière, ICM Paris, France
| | - Emmanuel Roze
- Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC UMR S1127, Institut du Cerveau et de la Moelle épinière, ICM Paris, France ; Département des Maladies du Système Nerveux, AP-HP, Hôpital Pitié Salpêtrière Paris, France
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13
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Manara R, Salvalaggio A, Citton V, Palumbo V, D'Errico A, Elefante A, Briani C, Cantone E, Ottaviano G, Pellecchia MT, Greggio NA, Weis L, D'Agosto G, Rossato M, De Carlo E, Napoli E, Coppola G, Di Salle F, Brunetti A, Bonanni G, Sinisi AA, Favaro A. Brain anatomical substrates of mirror movements in Kallmann syndrome. Neuroimage 2014; 104:52-8. [PMID: 25300200 DOI: 10.1016/j.neuroimage.2014.09.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 09/25/2014] [Accepted: 09/29/2014] [Indexed: 10/24/2022] Open
Abstract
Among male patients affected by Kallmann syndrome, a genetically determined disease due to defective neural migration leading to hypogonadropic hypogonadism and hypo/anosmia, about 40% present the peculiar phenomenon of mirror movements, i.e. involuntary movements mirroring contralateral voluntary hand movements. Several pathogenic hypotheses have been proposed, but the ultimate neurological mechanisms are still elusive. The aim of the present study was to investigate brain anatomical substrates of mirror movements in Kallmann syndrome by means of a panel of quantitative MRI analyses. Forty-nine male Kallmann syndrome patients underwent brain MRI. The study protocol included 3D-T1-weighted gradient echo, fluid attenuated inversion recovery and diffusion tensor imaging. Voxel-based morphometry, sulcation, curvature and cortical thickness analyses and tract based spatial statistics were performed using SPM8, Freesurfer and FSL. All patients underwent a complete physical and neurological examination including the evaluation of mirror movements (according to the Woods and Teuber criteria). Kallmann syndrome patients presenting with mirror movements (16/49, 32%) displayed the following brain changes: 1) increased gray matter density in the depth of the left precentral sulcus behind the middle frontal gyrus; 2) decreased cortical thickness in the precentral gyrus bilaterally, in the depth of right precentral sulcus and in the posterior portion of the right superior frontal gyrus; and 3) decreased fractional anisotropy in the left hemisphere involving the temporal lobe and peritrigonal white matter. No differences were shown by cortical curvature and sulcation analyses. The composite array of brain changes observed in Kallmann syndrome patients with mirror movements likely represents the anatomical-structural underpinnings leading to the peculiar derangement of the complex circuitry committed to unilateral hand voluntary movements.
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Affiliation(s)
- R Manara
- Neuroradiology, Dept. of Medicine and Surgery, University of Salerno, Italy.
| | - A Salvalaggio
- Neuroradiology, Dept. of Scienze Biomediche Avanzate, Federico II University, Napoli, Italy.
| | - V Citton
- IRCCS S. Camillo, Venezia, Italy.
| | - V Palumbo
- Dept. of Clinical and Experimental Medicine and Surgery, Endocrinology and Medical Andrology Section, Second University of Napoli, Italy.
| | - A D'Errico
- Neuroradiology, Dept. of Scienze Biomediche Avanzate, Federico II University, Napoli, Italy.
| | - A Elefante
- Neuroradiology, Dept. of Scienze Biomediche Avanzate, Federico II University, Napoli, Italy.
| | - C Briani
- Neurology, Dept. of Neurosciences, University of Padova, Italy.
| | - E Cantone
- Ent. Section, Dept. of Neurosciences, "Federico II" University, Napoli, Italy; Dept. of Molecular and Cellular Biology and Pathology, "Federico II" University, Napoli, Italy.
| | - G Ottaviano
- Otolaryngology Section, Dept. of Neurosciences, University of Padova, Italy.
| | - M T Pellecchia
- Neurology, Dept. of Medicine and Surgery, University of Salerno, Italy.
| | - N A Greggio
- UOS di Endocrinolgia Pediatrica e Adolescentologia, D.A.I.S. per la Salute della Donna e del Bambino, Azienda Ospedaliera - University of Padova, Italy.
| | - L Weis
- Neuroradiology, Dept. of Scienze Biomediche Avanzate, Federico II University, Napoli, Italy.
| | - G D'Agosto
- Medicanova, Diagnostic Center, Battipaglia (SA), Italy.
| | - M Rossato
- Clinica Medica III, Dept. of Medicine (DIMED), University of Padova, Italy.
| | - E De Carlo
- Clinica Medica III, Dept. of Medicine (DIMED), University of Padova, Italy.
| | - E Napoli
- Medicanova, Diagnostic Center, Battipaglia (SA), Italy.
| | - G Coppola
- Child and Adolescent Neuropsychiatry, University of Salerno, Italy.
| | - F Di Salle
- Neuroradiology, Dept. of Medicine and Surgery, University of Salerno, Italy.
| | - A Brunetti
- Neuroradiology, Dept. of Scienze Biomediche Avanzate, Federico II University, Napoli, Italy.
| | - G Bonanni
- Unità di Endocrinologia, Dept. of Medicine (DIMED), University of Padova, Italy.
| | - A A Sinisi
- Dept. of Clinical and Experimental Medicine and Surgery, Endocrinology and Medical Andrology Section, Second University of Napoli, Italy.
| | - A Favaro
- Psychiatry, Dept. of Neurosciences, University of Padova, Italy.
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14
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Gallea C, Popa T, Hubsch C, Valabregue R, Brochard V, Kundu P, Schmitt B, Bardinet E, Bertasi E, Flamand-Roze C, Alexandre N, Delmaire C, Méneret A, Depienne C, Poupon C, Hertz-Pannier L, Cincotta M, Vidailhet M, Lehericy S, Meunier S, Roze E. RAD51 deficiency disrupts the corticospinal lateralization of motor control. Brain 2013; 136:3333-46. [DOI: 10.1093/brain/awt258] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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15
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Garcia-Gonzalez D, Murcia-Belmonte V, Clemente D, De Castro F. Olfactory system and demyelination. Anat Rec (Hoboken) 2013; 296:1424-34. [PMID: 23904351 DOI: 10.1002/ar.22736] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 09/18/2012] [Accepted: 11/29/2012] [Indexed: 01/04/2023]
Abstract
Within the central nervous system, the olfactory system represents one of the most exciting scenarios since it presents relevant examples of long-life sustained neurogenesis and continuous axonal outgrowth from the olfactory epithelium with the subsequent plasticity phenomena in the olfactory bulb. The olfactory nerve is composed of nonmyelinated axons with interesting ontogenetic interpretations. However, the centripetal projections from the olfactory bulb are myelinated axons which project to more caudal areas along the lateral olfactory tract. In consequence, demyelination has not been considered as a possible cause of the olfactory symptoms in those diseases in which this sense is impaired. One prototypical example of an olfactory disease is Kallmann syndrome, in which different mutations give rise to combined anosmia and hypogonadotropic hypogonadism, together with different satellite symptoms. Anosmin-1 is the extracellular matrix glycoprotein altered in the X-linked form of this disease, which participates in cell adhesion and migration, and axonal outgrowth in the olfactory system and in other regions of the central nervous system. Recently, we have described a new patho-physiological role of this protein in the absence of spontaneous remyelination in multiple sclerosis. In the present review, we hypothesize about how both main and satellite neurological symptoms of Kallmann syndrome may be explained by alterations in the myelination. We revisit the relationship between the olfactory system and myelin highlighting that minor histological changes should not be forgotten as putative causes of olfactory malfunction.
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Affiliation(s)
- D Garcia-Gonzalez
- Grupo de Neurobiología del Desarrollo-GNDe, Hospital Nacional de Parapléjicos-SESCAM, Toledo, Spain
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16
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Interhemispheric control of unilateral movement. Neural Plast 2012; 2012:627816. [PMID: 23304559 PMCID: PMC3523159 DOI: 10.1155/2012/627816] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 11/04/2012] [Indexed: 11/25/2022] Open
Abstract
To perform strictly unilateral movements, the brain relies on a large cortical and subcortical network. This network enables healthy adults to perform complex unimanual motor tasks without the activation of contralateral muscles. However, mirror movements (involuntary movements in ipsilateral muscles that can accompany intended movement) can be seen in healthy individuals if a task is complex or fatiguing, in childhood, and with increasing age. Lateralization of movement depends on complex interhemispheric communication between cortical (i.e., dorsal premotor cortex, supplementary motor area) and subcortical (i.e., basal ganglia) areas, probably coursing through the corpus callosum (CC). Here, we will focus on transcallosal interhemispheric inhibition (IHI), which facilitates complex unilateral movements and appears to play an important role in handedness, pathological conditions such as Parkinson's disease, and stroke recovery.
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McGregor KM, Heilman KM, Nocera JR, Patten C, Manini TM, Crosson B, Butler AJ. Aging, aerobic activity and interhemispheric communication. Brain Sci 2012; 2:634-48. [PMID: 24961264 PMCID: PMC4061818 DOI: 10.3390/brainsci2040634] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 11/02/2012] [Accepted: 11/13/2012] [Indexed: 11/08/2022] Open
Abstract
Recent studies have shown that during unimanual motor tasks, aging adults show bilateral recruitment of primary motor cortex (M1), while younger adults show a suppression of the ipsilateral motor cortex. Additional work has indicated that increased bilateral M1 recruitment in older adults may be deleterious when performing some motor tasks. However, higher levels of physical fitness are associated with improved dexterity and fitness may mitigate the loss of both inhibitory and excitatory communication in aging adults. The goal of this study was to assess dexterity and interhemispheric motor communication in physically fit and sedentary middle-age (40-60 years) right handed participants using tests of hand deftness and transcranial magnetic stimulation (TMS). To behaviorally assess the influence of interhemispheric communication on motor performance, participants also perform the coin rotation deftness task while maintaining pinch force with the opposite hand (bimanual condition). We correlated these behavioral measures with the ipsilateral silent period using TMS to assess interhemispheric inhibition. Our results show that the middle-aged adults who were physically fit had better dexterity of their right hand (finger tapping and peg-board). When performing the coin rotation task the fit group had no between hand differences, but the sedentary group's left hand performance was inferior to the their right hand. We found that better dexterity correlated with ipsilateral silent period duration (greater inhibition) thereby supporting the postulate that fitness improves interhemispheric motor communication.
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Affiliation(s)
- Keith M McGregor
- Atlanta Rehabilitation Research and Development Center of Excellence, Department of Veteran's Affairs, Decatur, GA 30033, USA.
| | - Kenneth M Heilman
- Department of Veteran's Affairs Brain Rehabilitation and Research Center, Gainesville, FL 32609, USA.
| | - Joe R Nocera
- Atlanta Rehabilitation Research and Development Center of Excellence, Department of Veteran's Affairs, Decatur, GA 30033, USA.
| | - Carolynn Patten
- Department of Veteran's Affairs Brain Rehabilitation and Research Center, Gainesville, FL 32609, USA.
| | - Todd M Manini
- Department of Aging and Geriatric Research, University of Florida, Gainesville, FL 32611, USA.
| | - Bruce Crosson
- Atlanta Rehabilitation Research and Development Center of Excellence, Department of Veteran's Affairs, Decatur, GA 30033, USA.
| | - Andrew J Butler
- Atlanta Rehabilitation Research and Development Center of Excellence, Department of Veteran's Affairs, Decatur, GA 30033, USA.
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Minzenberg MJ, Yoon JH, Soosman SK, Carter CS. Excessive contralateral motor overflow in schizophrenia measured by fMRI. Psychiatry Res 2012; 202:38-45. [PMID: 22608155 DOI: 10.1016/j.pscychresns.2012.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 03/01/2012] [Accepted: 03/26/2012] [Indexed: 11/25/2022]
Abstract
Schizophrenia is characterized by significant problems in control of behavior; however, the disturbances in neural systems that control movement remain poorly characterized. We used functional magnetic resonance imaging (fMRI) to evaluate the origin of motor overflow in schizophrenia. Twenty-seven clinically stable medicated outpatients with Diagnostic and Statistical Manual, 4th edition, text revision (DSM-IV-TR)-defined schizophrenia (SZ), and 18 healthy control (HC) subjects, all right-handed, performed a dominant-handed, single-choice visual sensorimotor reaction time paradigm during fMRI. Voxel-wise analyses were conducted within sensorimotor cortical and striatal regions on general linear model (GLM)-derived measures of blood oxygen level-dependent (BOLD) signal change. The SZ group was not different from the HC group in reaction time, activation in somatosensory or motor cortices ipsilateral to the active (intended) descending corticospinal tract, nor visual cortex. However, in the right hemisphere (contralateral to the active M1), the SZ group showed significantly higher activation in primary motor cortex and adjacent premotor and somatosensory cortices (right Brodmann areas (BA) 1 through 4, and 6), and significantly lower activation in bilateral basal ganglia. Right BA 4 activation was strongly related to disorganization and poverty symptoms (and unrelated to medications) in the patient group. This study provides evidence in SZ of excessive neural activity in motor cortex contralateral to the intended primary motor cortex, which may form the basis for altered motor laterality and motor overflow previously observed, and disorganized behavior. This pathological motor overflow may be partly due to altered modulation of intended movement within the basal ganglia and premotor cortex.
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Affiliation(s)
- Michael J Minzenberg
- Department of Psychiatry, University of California, Davis School of Medicine, Sacramento, CA, USA.
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FGF-2 and Anosmin-1 are selectively expressed in different types of multiple sclerosis lesions. J Neurosci 2011; 31:14899-909. [PMID: 22016523 DOI: 10.1523/jneurosci.1158-11.2011] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Multiple sclerosis is a demyelinating disease that affects ≈ 2,000,000 people worldwide. In the advanced stages of the disease, endogenous oligodendrocyte precursors cannot colonize the lesions or differentiate into myelinating oligodendrocytes. During development, both FGF-2 and Anosmin-1 participate in oligodendrocyte precursor cell migration, acting via the FGF receptor 1 (FGFR1). Hence, we performed a histopathological and molecular analysis of these developmental modulators in postmortem tissue blocks from multiple sclerosis patients. Accordingly, we demonstrate that the distribution of FGF-2 and Anosmin-1 varies between the different types of multiple sclerosis lesions: FGF-2 is expressed only within active lesions and in the periplaque of chronic lesions, whereas Anosmin-1 is upregulated within chronic lesions and is totally absent in active lesions. We show that the endogenous oligodendrocyte precursor cells recruited toward chronic-active lesions express FGFR1, possibly in response to the FGF-2 produced by microglial cells in the periplaque. Also in human tissue, FGF-2 is upregulated in perivascular astrocytes in regions of the normal-appearing gray matter, where the integrity of the blood-brain barrier is compromised. In culture, FGF-2 and Anosmin-1 influence adult mouse oligodendrocyte precursor cell migration in the same manner as at embryonic stages, providing an explanation for the histopathological observations: FGF-2 attracts/enhances its migration, which is hindered by Anosmin-1. We propose that FGF-2 and Anosmin-1 are markers for the histopathological type and the level of inflammation of multiple sclerosis lesions, and that they may serve as novel pharmacogenetic targets to design future therapies that favor effective remyelination and protect the blood-brain barrier.
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Ohtsuka H, Sasada S, Nakajima T, Futatsubashi G, Shimizu E, Komiyama T. Tuning of the excitability of transcortical cutaneous reflex pathways during mirror-like activity. Exp Brain Res 2011; 216:135-44. [PMID: 22076404 DOI: 10.1007/s00221-011-2917-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 10/20/2011] [Indexed: 11/25/2022]
Abstract
Voluntary contraction of a muscle generates electromyographic (EMG) activity in the homologous muscle on the opposite side (mirror-like activity), not only in pathological states and in infants but also in healthy adults. Few studies have examined whether the cutaneous reflexes during the preparatory period of a reaction time task are affected by mirror-like activity. In the present study, we investigated the modulation of the cutaneous reflexes in the left first interosseous (FDI) muscle in 9 healthy subjects while they performed a quick abduction of the right index finger during a reaction time task. Cutaneous reflexes were elicited by applying non-noxious electrical stimulation to the left index finger. We found that mirror-like activity occurred in the left FDI at approximately the onset of EMG activity in the right FDI. The excitatory E2 component was selectively increased at ~75 ms after the "Go" signal, which corresponded to the onset of mirror-like activity. The inhibitory I2 (~90 ms) component was tuned consistently into excitation after the "Go" signal. These findings suggest that long latency reflexes, possibly transcortical cutaneous reflexes, are finely tuned in relation to mirror-like activity.
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Affiliation(s)
- Hiroyuki Ohtsuka
- Department of Cognitive Behavioral Physiology, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuouku, Chiba 260-8670, Japan
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Neural crest and ectodermal cells intermix in the nasal placode to give rise to GnRH-1 neurons, sensory neurons, and olfactory ensheathing cells. J Neurosci 2011; 31:6915-27. [PMID: 21543621 DOI: 10.1523/jneurosci.6087-10.2011] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The origin of GnRH-1 cells and olfactory ensheathing cells has been controversial. Genetic Cre-lox lineage tracing of the neural crest (NC) versus ectodermal contribution to the developing nasal placode was performed using two complementary mouse models, the NC-specific Wnt1Cre mouse line and an ectodermal-specific Crect mouse line. Using these lines we prove that the NC give rise to the olfactory ensheathing cells and subpopulations of GnRH-1 neurons, olfactory and vomeronasal cells. These data demonstrate that Schwann cells and olfactory ensheathing cells share a common developmental origin. Furthermore, the results indicate that certain conditions that impact olfaction and sexual development, such as Kallmann syndrome, may be in part neurocristopathies.
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Congenital mirror movements: a clue to understanding bimanual motor control. J Neurol 2011; 258:1911-9. [DOI: 10.1007/s00415-011-6107-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 05/10/2011] [Accepted: 05/12/2011] [Indexed: 10/18/2022]
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Tsuboi F, Nishimura Y, Yoshino-Saito K, Isa T. Neuronal mechanism of mirror movements caused by dysfunction of the motor cortex. Eur J Neurosci 2010; 32:1397-406. [DOI: 10.1111/j.1460-9568.2010.07395.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Bonnet C, Roubertie A, Doummar D, Bahi-Buisson N, Cochen de Cock V, Roze E. Developmental and benign movement disorders in childhood. Mov Disord 2010; 25:1317-34. [DOI: 10.1002/mds.22944] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Koenigkam-Santos M, de Castro M, Versiani BR, Diniz PRB, Santos AC. Kallmann syndrome and mirror movements: White matter quantitative evaluation with magnetic resonance imaging. J Neurol Sci 2010; 292:40-4. [DOI: 10.1016/j.jns.2010.02.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2009] [Revised: 02/09/2010] [Accepted: 02/11/2010] [Indexed: 11/17/2022]
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Koenigkam-Santos M, Santos AC, Borduqui T, Versiani BR, Hallak JEC, Crippa JAS, Castro M. Whole-brain voxel-based morphometry in Kallmann syndrome associated with mirror movements. AJNR Am J Neuroradiol 2008; 29:1799-804. [PMID: 18768731 DOI: 10.3174/ajnr.a1202] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND AND PURPOSE There are 2 main hypotheses concerning the cause of mirror movements (MM) in Kallmann syndrome (KS): abnormal development of the primary motor system, involving the ipsilateral corticospinal tract; and lack of contralateral motor cortex inhibitory mechanisms, mainly through the corpus callosum. The purpose of our study was to determine white and gray matter volume changes in a KS population by using optimized voxel-based morphometry (VBM) and to investigate the relationship between the abnormalities and the presence of MM, addressing the 2 mentioned hypotheses. MATERIALS AND METHODS T1-weighted volumetric images from 21 patients with KS and 16 matched control subjects were analyzed with optimized VBM. Images were segmented and spatially normalized, and these deformation parameters were then applied to the original images before the second segmentation. Patients were divided into groups with and without MM, and a t test statistic was then applied on a voxel-by-voxel basis between the groups and controls to evaluate significant differences. RESULTS When considering our hypothesis a priori, we found that 2 areas of increased gray matter volume, in the left primary motor and sensorimotor cortex, were demonstrated only in patients with MM, when compared with healthy controls. Regarding white matter alterations, no areas of altered volume involving the corpus callosum or the projection of the corticospinal tract were demonstrated. CONCLUSION The VBM study did not show significant white matter changes in patients with KS but showed gray matter alterations in keeping with a hypertrophic response to a deficient pyramidal decussation in patients with MM. In addition, gray matter alterations were observed in patients without MM, which can represent more complex mechanisms determining the presence or absence of this symptom.
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Affiliation(s)
- M Koenigkam-Santos
- Division of Radiology, School of Medicine of Ribeirao Preto-University of Sao Paulo, Ribeirao Preto, SP, Brazil.
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Clemente D, Esteban PF, Del Valle I, Bribián A, Soussi-Yanicostas N, Silva A, De Castro F. Expression pattern of Anosmin-1 during pre- and postnatal rat brain development. Dev Dyn 2008; 237:2518-28. [DOI: 10.1002/dvdy.21659] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Hbers A, Orekhov Y, Ziemann U. Interhemispheric motor inhibition: its role in controlling electromyographic mirror activity. Eur J Neurosci 2008; 28:364-71. [DOI: 10.1111/j.1460-9568.2008.06335.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cincotta M, Ziemann U. Neurophysiology of unimanual motor control and mirror movements. Clin Neurophysiol 2008; 119:744-62. [DOI: 10.1016/j.clinph.2007.11.047] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 11/17/2007] [Accepted: 11/23/2007] [Indexed: 10/22/2022]
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30
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Persistent mirror movements for over sixty years: The underlying mechanisms in a cerebral palsy patient. Clin Neurophysiol 2008; 119:80-7. [DOI: 10.1016/j.clinph.2007.09.120] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 09/10/2007] [Accepted: 09/30/2007] [Indexed: 11/22/2022]
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Li JY, Espay AJ, Gunraj CA, Pal PK, Cunic DI, Lang AE, Chen R. Interhemispheric and ipsilateral connections in Parkinson's disease: relation to mirror movements. Mov Disord 2007; 22:813-21. [PMID: 17290459 DOI: 10.1002/mds.21386] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Mirror movements (MM) occur in early, asymmetric Parkinson's disease (PD). To examine the pathophysiology of MM in PD, we studied 13 PD patients with MM (PD-MM), 7 PD patients without MM (PD-NM), and 14 normal subjects. Cross-correlogram did not detect common synaptic input to motoneuron pools innervating homologous hand muscles in PD-MM patients. Transcranial magnetic stimulation studies showed no significant difference in ipsilateral motor-evoked potentials between PD-MM patients and normal subjects. The MM side of PD-MM patients showed a slower increase in ipsilateral silent period area with higher level of muscle contraction than the non-MM side and normal subjects. There was less interhemispheric inhibition (IHI) at long interstimulus intervals of 20 to 50 ms in PD-MM than PD-NM. IHI reduced short interval intracortical inhibition in normal subjects and PD-NM, but not in PD-MM. IHI significantly increased intracortical facilitation in PD-MM and PD-NM patients, but not in normal subjects. Our results suggest that MM in PD is due to activation of the contralateral motor cortex. PD-MM patients had reduced transcallosal inhibitory effects on cortical output neurons and on intracortical inhibitory circuits compared to PD-NM patients and controls. These deficits in transcallosal inhibition may contribute to MM in PD patients.
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Affiliation(s)
- Jie-Yuan Li
- Division of Neurology, Department of Medicine, Toronto Western Research Institute, University of Toronto, Toronto, Ontario, Canada
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Verstynen T, Spencer R, Stinear CM, Konkle T, Diedrichsen J, Byblow WD, Ivry RB. Ipsilateral corticospinal projections do not predict congenital mirror movements: a case report. Neuropsychologia 2006; 45:844-52. [PMID: 17023008 PMCID: PMC2275211 DOI: 10.1016/j.neuropsychologia.2006.08.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Revised: 08/11/2006] [Accepted: 08/18/2006] [Indexed: 11/22/2022]
Abstract
Congenital mirror movements (CMMs) are involuntary, symmetric movements of one hand during the production of voluntary movements with the other. CMMs have been attributed to a range of physiological mechanisms, including excessive ipsilateral projections from each motor cortex to distal extremities. We examined this hypothesis with an individual showing pronounced CMMs. Mirror movements were characterized for a set of hand muscles during a simple contraction task. Transcranial magnetic stimulation (TMS) was then used to map the relative input to each muscle from both motor cortices. Contrary to our expectations, CMMs were most prominent for muscles with the strongest contralateral representation rather than in muscles that were activated by stimulation of either hemisphere. These findings support a bilateral control hypothesis whereby CMMs result from the recruitment of both motor cortices during intended unimanual movements. Consistent with this hypothesis, bilateral motor cortex activity was evident during intended unimanual movements in an fMRI study. To assess the level at which bilateral recruitment occurs, motor cortex excitability during imagined unimanual movements was assessed with TMS. Facilitory excitation was only observed in the contralateral motor cortex. Thus, the bilateral recruitment of the hemispheres for unilateral actions in individuals with CMMs appears to occur during movement execution rather than motor planning.
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Affiliation(s)
- T Verstynen
- Department of Psychology, University of California, Berkeley, CA 94720, USA.
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Cincotta M, Borgheresi A, Balestrieri F, Giovannelli F, Ragazzoni A, Vanni P, Benvenuti F, Zaccara G, Ziemann U. Mechanisms underlying mirror movements in Parkinson's disease: A transcranial magnetic stimulation study. Mov Disord 2006; 21:1019-25. [PMID: 16547917 DOI: 10.1002/mds.20850] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The neural mechanisms underlying unintended mirror movements (MMs) of one hand during unimanual movements of the other hand in patients with Parkinson's disease (PD) are largely unexplored. Here we used surface electromyographic (EMG) analysis and focal transcranial magnetic stimulation (TMS) to investigate the pathophysiological substrate of MMs in four PD patients. Surface EMG was recorded from both abductor pollicis brevis (APB) and first dorsal interosseous (FDI) muscles. Cross-correlation EMG analysis revealed no common motor drive to the two APBs during intended unimanual tasks. Focal TMS of either primary motor cortex (M1) elicited normal motor-evoked potentials (MEPs) in the contralateral APB, whereas MEPs were not seen in the ipsilateral hand. During either mirror or voluntary APB contraction, focal TMS of the contralateral M1 produced a long-lasting silent period (SP), whereas stimulation of the ipsilateral M1 produced a short-lasting SP. During either mirror or voluntary finger tapping, 5 Hz repetitive TMS (rTMS) of the contralateral M1 disrupted EMG activity in the target FDI, whereas the effects of rTMS of the ipsilateral M1 were by far slighter. During either mirror or voluntary APB contraction, paired-pulse TMS showed a reduction of short-interval intracortical inhibition in the contralateral M1. These findings provide converging evidence that, in PD, MMs do not depend on unmasking of ipsilateral projections but are explained by motor output along the crossed corticospinal projection from the mirror M1.
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Uttner I, Mai N, Esslinger O, Danek A. Quantitative evaluation of mirror movements in adults with focal brain lesions. Eur J Neurol 2005; 12:964-75. [PMID: 16324090 DOI: 10.1111/j.1468-1331.2005.01098.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Mirror movements (MM), involuntary movements of homologous muscles opposite to unilateral limb activity, decrease in the course of motor development, but may reappear in adults after brain damage. To better characterize this type of acquired MM, grip forces of 36 healthy subjects and 35 patients suffering from focal brain lesions were compared. Holding force transducers in a pinch grip between thumb and index fingers of each hand, subjects had to repeatedly change the grip force in one hand, whilst the other (mirror) hand just had to prevent the manipulandum from dropping. In a second task, force changes had to be produced either in a symmetric or in an antiparallel manner. No significant group differences between patients and controls in the extent of coupling were found. During unimanual squeezing, only six patients had a co-activation in the pathologic range. Whilst performing bimanual asymmetric grip force changes, pathologic coupling was seen only in five patients. No association was found between the presence of pathologic MM and clinical or neuroanatomical features. Brain lesions in adults seem only rarely to be associated with pathologic MM. They might be non-specific and not related to the characteristics of the lesion.
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Affiliation(s)
- I Uttner
- Neurologische Klinik, Universität Ulm, Oberer Eselsberg, Germany.
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Carson RG. Neural pathways mediating bilateral interactions between the upper limbs. ACTA ACUST UNITED AC 2005; 49:641-62. [PMID: 15904971 DOI: 10.1016/j.brainresrev.2005.03.005] [Citation(s) in RCA: 258] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Revised: 03/09/2005] [Accepted: 03/15/2005] [Indexed: 11/17/2022]
Abstract
The ease with which we perform tasks such as opening the lid of a jar, in which the two hands execute quite different actions, belies the fact that there is a strong tendency for the movements of the upper limbs to be drawn systematically towards one another. Mirror movements, involuntary contractions during intended unilateral engagement of the opposite limb, are considered pathological, as they occur in association with specific disorders of the CNS. Yet they are also observed frequently in normally developing children, and motor irradiation, an increase in the excitability of the (opposite) homologous motor pathways when unimanual movements are performed, is a robust feature of the mature motor system. The systematic nature of the interactions that occur between the upper limbs has also given rise to the expectation that functional improvements in the control of a paretic limb may occur when movements are performed in a bimanual context. In spite of the ubiquitous nature of these phenomena, there is remarkably little consensus concerning the neural basis of their mediation. In the present review, consideration is given to the putative roles of uncrossed corticofugal fibers, branched bilateral corticomotoroneuronal projections, and segmental networks. The potential for bilateral interactions to occur in various brain regions including the primary motor cortex, the supplementary motor area, non-primary motor areas, the basal ganglia, and the cerebellum is also explored. This information may provide principled bases upon which to evaluate and develop task and deficit-specific programs of movement rehabilitation and therapy.
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Affiliation(s)
- R G Carson
- Perception and Motor Systems Laboratory, The University of Queensland, Brisbane, Queensland 4072, Australia.
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Abstract
The crossing of nerve tracts from one hemisphere in the brain to the contralateral sense organ or limb is a common pattern throughout the CNS, which occurs at specialised bridging points called decussations or commissures. Evolutionary and teleological arguments suggest that midline crossing emerged in response to distinct physiological and anatomical constraints. Several genetic and developmental disorders involve crossing defects or mirror movements, including Kallmann's and Klippel-Feil syndrome, and further defects can also result from injury. Crossed pathways are also involved in recovery after CNS lesions and may allow for compensation for damaged areas. The development of decussation is under the control of a host of signalling molecules. Growing understanding of the molecular processes underlying the formation of these structures offers hope for new diagnostic and therapeutic interventions.
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Affiliation(s)
- Serge Vulliemoz
- Neurology Department, Geneva University Hospital, Geneva, Switzerland
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37
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Hoy KE, Fitzgerald PB, Bradshaw JL, Armatas CA, Georgiou-Karistianis N. Investigating the cortical origins of motor overflow. ACTA ACUST UNITED AC 2004; 46:315-27. [PMID: 15571773 DOI: 10.1016/j.brainresrev.2004.07.013] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2004] [Indexed: 11/22/2022]
Abstract
Motor overflow refers to the involuntary movements which may accompany the production of voluntary movements. While overflow is not usually seen in the normal population, it does present in children and the elderly, as well as those suffering certain neurological dysfunctions. Advancements in methodology over the last decade have allowed for more convincing conclusions regarding the cortical origins of motor overflow. However, despite significant research, the exact mechanism underlying the production of motor overflow is still unclear. This review presents a more comprehensive conceptualization of the theories of motor overflow, which have often been only vaguely defined. Further, the major findings are explored in an attempt to differentiate the competing theories of motor overflow production. This exploration is done in the context of a range of neurological and psychiatric disorders, in order to elucidate the possible underlying mechanisms of overflow.
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Affiliation(s)
- Kate E Hoy
- Experimental Neuropsychology Research Unit, Psychology Department, Monash University, Clayton 3800, Victoria, Australia.
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38
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Jović N, Drezgić M. [Neurological disorders in patients with Kallmann's syndrome]. VOJNOSANIT PREGL 2004; 61:173-80. [PMID: 15296123 DOI: 10.2298/vsp0402173j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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39
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Cincotta M, Borgheresi A, Balzini L, Vannucchi L, Zeloni G, Ragazzoni A, Benvenuti F, Zaccara G, Arnetoli G, Ziemann U. Separate ipsilateral and contralateral corticospinal projections in congenital mirror movements: Neurophysiological evidence and significance for motor rehabilitation. Mov Disord 2003; 18:1294-300. [PMID: 14639670 DOI: 10.1002/mds.10545] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The neurophysiological hallmark of congenital mirror movements (MM) are fast-conducting corticospinal projections from the hand area of one primary motor cortex to both sides of the spinal cord. It is still unclear whether the abnormal ipsilateral projection originates through branching fibres from the normal contralateral projection or constitutes a separate ipsilateral projection. To clarify this question, we used focal paired-pulse transcranial magnetic stimulation to test task-related modulation of short-interval intracortical inhibition (SICI) in the abductor pollicis brevis (APB) muscles of a 15-year-old girl (Patient 1) and a 40-year-old woman (Patient 2) with congenital MM. In both patients, during intended unilateral APB contraction, SICI decreased markedly in the "task" APB but remained unchanged in the "mirror" APB when compared to muscle rest. In contrast, spinal excitability as tested with H reflexes increased similarly in the task and mirror flexor carpi radialis muscles. This dissociation of task-related SICI modulation strongly supports the existence of a separate ipsilateral fast-conducting corticospinal projection. In Patient 1, we tested the functional significance of this separate ipsilateral projection during 7 months of motor rehabilitation training, which was designed to facilitate unilateral finger movements. A marked reduction of MM was observed after training, suggesting that unwanted mirror activity in the ipsilateral pathway can be suppressed by learning.
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Vandermeeren Y, Sébire G, Grandin CB, Thonnard JL, Schlögel X, De Volder AG. Functional reorganization of brain in children affected with congenital hemiplegia: fMRI study. Neuroimage 2003; 20:289-301. [PMID: 14527589 DOI: 10.1016/s1053-8119(03)00262-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Using functional magnetic resonance imaging, the brain activation related to unilateral sequential finger-to-thumb opposition was studied in six children with a right congenital hemiplegia of cortical origin. They were compared to six age-matched controls. In the control group, movements with either hand asymmetrically activated the sensorimotor cortex and premotor areas in both cerebral hemispheres with a typical contralateral predominance. By contrast, paretic finger movements activated both hemispheres in the hemiplegic patients, with a strong ipsilateral predominance favoring the undamaged hemisphere. The activation induced by nonparetic finger movements was restricted to the contralateral undamaged hemisphere. Furthermore, the level of activation in the undamaged cortex was partly related to residual finger dexterity, according to covariance analysis. These activation patterns indicate an adaptive reorganization of the cortical motor networks in this group of patients, with a prominent involvement of the undamaged hemisphere in the control of finger movements with either hand.
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Affiliation(s)
- Yves Vandermeeren
- Laboratory of Neurophysiology, Louvain School of Medicine, B-1200 Brussels, Belgium
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41
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Bouloux PM, Hu Y, MacColl G. Recent advances in the pathogenesis of Kallmann's syndrome. PROGRESS IN BRAIN RESEARCH 2003; 141:79-83. [PMID: 12508562 DOI: 10.1016/s0079-6123(02)41085-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Affiliation(s)
- Pierre-Marc Bouloux
- Centre for Neuroendocrinology, Royal Free and University College Medical School, London NW3 2QG, UK.
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Cincotta M, Borgheresi A, Ragazzoni A, Vanni P, Balestrieri F, Benvenuti F, Zaccara G, Ziemann U. Chapter 16 Motor control in mirror movements: studies with transcranial magnetic stimulation. ACTA ACUST UNITED AC 2003; 56:175-80. [PMID: 14677392 DOI: 10.1016/s1567-424x(09)70219-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Affiliation(s)
- M Cincotta
- U.O. di Neurologia, Azienda Sanitaria di Firenze, Ospedale S. Maria Nuova, Piazza S. Maria Nuova 1, 50122 Florence, Italy.
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Pohja M, Salenius S, Hari R. Cortico-muscular coupling in a human subject with mirror movements--a magnetoencephalographic study. Neurosci Lett 2002; 327:185-8. [PMID: 12113908 DOI: 10.1016/s0304-3940(02)00426-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We studied cortico-muscular coupling in a 15-year-old male suffering from congenital mirror movements (MMs) of hands. Cortex-muscle coherence was analyzed between magnetoencephalographic signals and the electromyograms (EMGs) recorded from both hands and feet during uni- and bilateral isometric contractions. Regardless of the side of the intended contraction, the motor cortex contralateral to the contraction was coupled to the muscles of both hands at 20-25 Hz. No coupling was found from the other, ipsilateral hemisphere. EMGs of the two hands were coupled during both intended uni- and bilateral contractions, but only during unilateral contractions could the coupling solely be explained by cortical activation. We suggest that our subject's MMs result from activation of an ipsilateral corticospinal projection, with involvement of additional synchronizing mechanisms at the subcortical, brainstem, or spinal level during bilateral contraction.
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Affiliation(s)
- Marjatta Pohja
- Brain Research Unit, Low Temperature Laboratory, Helsinki University of Technology, P.O. Box 2200, FIN-02015 HUT, Espoo, Finland.
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Abstract
Three new studies into the function of human anosmin-1 and related proteins in C. elegans and rodents show that these influence axon branching and axon targeting. The rodent anosmin appears to work at two stages of development, initially promoting axon outgrowth from the olfactory bulb and then stimulating branching from axons into the olfactory cortex. CeKal-1 further influences morphogenesis, and, as the human and nematode anosmins are functionally conserved, these studies provide insights into the pathogenesis of Kallmann syndrome (KS).
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Affiliation(s)
- Gavin MacColl
- Neuroendocrine Unit, Department of Medicine, Royal Free and University College Medical School, Royal Free Campus, Rowland Hill Street, London NW3 2PF, United Kingdom
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Cincotta M, Borgheresi A, Boffi P, Vigliano P, Ragazzoni A, Zaccara G, Ziemann U. Bilateral motor cortex output with intended unimanual contraction in congenital mirror movements. Neurology 2002; 58:1290-3. [PMID: 11971104 DOI: 10.1212/wnl.58.8.1290] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In congenital mirror movements (MM), it is unclear whether the "mirror" motor cortex (M1) produces output during intended unimanual movements. In two patients with MM, the cortical silent period (CSP) was abnormally short after focal transcranial magnetic stimulation (TMS) of either M1, but simultaneous bilateral TMS led to significant CSP lengthening. Thus, it is likely that the shortened CSP after unilateral TMS is caused by output from the nonstimulated M1, suggesting that both M1 produce output with intended unimanual movements in patients with MM.
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Affiliation(s)
- M Cincotta
- Unit of Neurology, Santa Maria Nuova Hospital, Florence, Italy.
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Vercueil L, Minotti L, Kahane P. Dystonia, mirror movement, and epileptic seizure. Epilepsia 2002; 43:321-3. [PMID: 11906519 DOI: 10.1046/j.1528-1157.2002.30401.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Laurent Vercueil
- Service de Neurologie and INSERM U318, CHU Grenoble, Grenoble, France.
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Foltys H, Sparing R, Boroojerdi B, Krings T, Meister IG, Mottaghy FM, Töpper R. Motor control in simple bimanual movements: a transcranial magnetic stimulation and reaction time study. Clin Neurophysiol 2001; 112:265-74. [PMID: 11165528 DOI: 10.1016/s1388-2457(00)00539-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Simple reaction time (RT) can be influenced by transcranial magnetic stimulation (TMS) to the motor cortex. Since TMS differentially affects RT of ipsilateral and contralateral muscles a combined RT and TMS investigation sheds light on cortical motor control of bimanual movements. METHODS Ten normal subjects and one subject with congenital mirror movements (MM) were investigated with a RT paradigm in which they had to move one or both hands in response to a visual go-signal. Suprathreshold TMS was applied to the motor cortex ipsilateral or contralateral to the moving hand at various interstimulus intervals (ISIs) after presentation of the go-signal. EMG recordings from the thenar muscles of both hands were used to determine the RT. RESULTS TMS applied to the ipsilateral motor cortex shortened RT when TMS was delivered simultaneously with the go-signal. With increasing ISI between TMS and go-signal the RT was progressively delayed. This delay was more pronounced if TMS was applied contralateral to the moving hand. When normal subjects performed bimanual movements the TMS-induced changes in RT were essentially the same as if they had used the hand in an unimanual task. In the subject with MM, TMS given at the time of the go-signal facilitated both the voluntary and the MM. With increasing ISI, however, RT for voluntary movements and MM increased in parallel. CONCLUSIONS Ipsilateral TMS affects the timing of hand movements to the same extent regardless of whether the hand is engaged in an unimanual or a bimanual movement. It can be concluded, therefore, that in normal subjects simple bimanual movements are controlled by each motor cortex independently. The results obtained in the subject with MM are consistent with the hypothesis that mirror movements originate from uncrossed corticospinal fibres. The alternative hypothesis that a deficit in transcallosal inhibition leads to MM in the contralateral motor cortex is not compatible with the presented data, because TMS applied to the motor cortex ipsilateral to a voluntary moved hand affected voluntary movements and MM to the same extent.
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Affiliation(s)
- H Foltys
- Department of Neurology, University Hospital RWTH, Pauwelsstrasse 30, 52057, Aachen, Germany
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Abstract
Magnetic resonance techniques have become increasingly important in neurology for defining: 1. brain, spinal cord and peripheral nerve or muscle structure; 2. pathological changes in tissue structures and properties; and 3. dynamic patterns of functional activation of the brain. New applications have been driven in part by advances in hardware, particularly improvements in magnet and gradient coil design. New imaging strategies allow novel approaches to contrast with, for example, diffusion imaging, magnetization transfer imaging, perfusion imaging and functional magnetic resonance imaging. In parallel with developments in hardware and image acquisition have been new approaches to image analysis. These have allowed quantitative descriptions of the image changes to be used for a precise, non-invasive definition of pathology. With the increasing capabilities and specificity of magnetic resonance techniques it is becoming more important that the neurologist is intimately involved in both the selection of magnetic resonance studies for patients and their interpretation. There is a need for considerably improved access to magnetic resonance technology, particularly in the acute or intensive care ward and in the neurosurgical theatre. This report illustrates several key developments. The task force concludes that magnetic resonance imaging is a major clinical tool of growing significance and offers recommendations for maximizing the potential future for magnetic resonance techniques in neurology.
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Harrison LM, Mayston MJ, Johansson RS. Reactive control of precision grip does not depend on fast transcortical reflex pathways in X-linked Kallmann subjects. J Physiol 2000; 527 Pt 3:641-52. [PMID: 10990548 PMCID: PMC2270096 DOI: 10.1111/j.1469-7793.2000.00641.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
It has been shown that subjects maintain grasp stability by automatically regulating grip force in response to loads applied tangentially to a manipulandum held using a precision grip. Signals from cutaneous mechanoreceptors convey the information necessary for both the initiation and scaling of responses. The central neural pathways that support these grip reactions are unknown. However, the latency of the increase in force is similar to that of 'long-latency' transcortical reflexes recorded from muscles following muscle stretch or electrical stimulation of digital nerves. This study assessed the importance of fast transcortical pathways for reactive grip responses by examining these responses in subjects with X-linked Kallmann's syndrome (XKS). Subjects were selected whose corticospinal projection, as assessed by magnetic brain stimulation, is essentially ipsilateral, and in whom the long-latency reflex components following digital nerve stimulation are only found contralateral to the stimulated side. Despite this anomaly of the fast corticospinal pathway, these XKS subjects responded in the same way as control subjects; grip response latencies were similar and responses were appropriately scaled. However, the non-operating hand of these XKS subjects often mirrored the grip force changes of the operating hand. Reflex force mirroring was most marked during the first 50 ms and the force output was always less than 20 % of that of the operating hand. We conclude, firstly, that somatosensory driven precision grip responses that support grasp stability do not depend on fast conducting corticospinal pathways in these subjects and, secondly, that such responses do not use those 'long-latency' reflex pathways probed by cutaneomuscular reflexes elicited by electrical stimulation of digital nerves.
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Affiliation(s)
- L M Harrison
- Department of Physiology, University College London, Gower Street, London WC1E 6BT, UK.
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Rowe JB, Frackowiak RS. The impact of brain imaging technology on our understanding of motor function and dysfunction. Curr Opin Neurobiol 1999; 9:728-34. [PMID: 10607634 DOI: 10.1016/s0959-4388(99)00025-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Brain imaging techniques have demonstrated functional specialisation of multiple areas within the motor system. They have also defined the patterns of interactions between these regions during normal motor function and in motor disorders. Functional imaging makes visible the changes in cortical activity that take place over time during motor functions, from the activations a fraction of a second before voluntary action to cortical neuronal plasticity several weeks after injury. Recently, the functional abnormalities underlying various acquired and developmental motor disorders have been described, as well as the effects of therapeutic intervention.
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Affiliation(s)
- J B Rowe
- Wellcome Department of Cognitive Neurology, Institute of Neurology, University College London, London, WC1N 3BG, UK.
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