Read by QxMD icon Read

mesencephalic locomotor region

Maria C Dadarlat, Michael P Stryker
Neurons in mouse primary visual cortex (V1) are selective for particular properties of visual stimuli. Locomotion causes a change in cortical state that leaves their selectivity unchanged but strengthens their responses. Both locomotion and the change in cortical state are thought to be initiated by projections from the mesencephalic locomotor region, the latter through a disinhibitory circuit in V1. By recording simultaneously from a large number of single neurons in alert mice viewing moving gratings, we investigated the relationship between locomotion and the information contained within the neural population...
April 5, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Claire Ewenczyk, Salma Mesmoudi, Cécile Gallea, Marie-Laure Welter, Bertrand Gaymard, Adèle Demain, Lydia Yahia Cherif, Bertrand Degos, Habib Benali, Pierre Pouget, Cyril Poupon, Stéphane Lehericy, Sophie Rivaud-Péchoux, Marie Vidailhet
OBJECTIVE: To describe the relation between gaze and posture/gait control in Parkinson disease (PD) and to determine the role of the mesencephalic locomotor region (MLR) and cortex-MLR connection in saccadic behavior because this structure is a major area involved in both gait/postural control and gaze control networks. METHODS: We recruited 30 patients with PD with or without altered postural control and 25 age-matched healthy controls (HCs). We assessed gait, balance, and neuropsychological status and separately recorded gait initiation and eye movements (visually guided saccades and volitional antisaccades)...
January 27, 2017: Neurology
Sophie B Sébille, Hayat Belaid, Anne-Charlotte Philippe, Arthur André, Brian Lau, Chantal François, Carine Karachi, Eric Bardinet
The mesencephalic locomotor region (MLR) is a highly preserved brainstem structure in vertebrates. The MLR performs a crucial role in locomotion but also controls various other functions such as sleep, attention, and even emotion. The MLR comprises the pedunculopontine (PPN) and cuneiform nuclei (CuN) but their specific roles are still unknown in primates. Here, we sought to characterise the inputs and outputs of the PPN and CuN to and from the basal ganglia, thalamus, amygdala and cortex, with a specific interest in identifying functional anatomical territories...
February 15, 2017: NeuroImage
Anke H Snijders, Kaoru Takakusaki, Bettina Debu, Andres M Lozano, Vibhor Krishna, Alfonso Fasano, Tipu Z Aziz, Stella M Papa, Stewart A Factor, Mark Hallett
Freezing of gait (FOG) is a common and debilitating, but largely mysterious, symptom of Parkinson disease. In this review, we will discuss the cerebral substrate of FOG focusing on brain physiology and animal models. Walking is a combination of automatic movement processes, afferent information processing, and intentional adjustments. Thus, normal gait requires a delicate balance between various interacting neuronal systems. To further understand gait control and specifically FOG, we will discuss the basic physiology of gait, animal models of gait disturbance including FOG, alternative etiologies of FOG, and functional magnetic resonance studies investigating FOG...
November 2016: Annals of Neurology
Laurent Goetz, Brigitte Piallat, Manik Bhattacharjee, Hervé Mathieu, Olivier David, Stéphan Chabardès
The mesencephalic reticular formation (MRF) mainly composed by the pedunculopontine and the cuneiform nuclei is involved in the control of several fundamental brain functions such as locomotion, rapid eye movement sleep and waking state. On the one hand, the role of MRF neurons in locomotion has been investigated for decades in different animal models, including in behaving nonhuman primate (NHP) using extracellular recordings. On the other hand, MRF neurons involved in the control of waking state have been consistently shown to constitute the cholinergic component of the reticular ascending system...
July 2016: Journal of Neural Transmission
Laurent Goetz, Brigitte Piallat, Manik Bhattacharjee, Hervé Mathieu, Olivier David, Stéphan Chabardès
UNLABELLED: The mesencephalic reticular formation (MRF) is formed by the pedunculopontine and cuneiform nuclei, two neuronal structures thought to be key elements in the supraspinal control of locomotion, muscle tone, waking, and REM sleep. The role of MRF has also been advocated in modulation of state of arousal leading to transition from wakefulness to sleep and it is further considered to be a main player in the pathophysiology of gait disorders seen in Parkinson's disease. However, the existence of a mesencephalic locomotor region and of an arousal center has not yet been demonstrated in primates...
May 4, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Sandra Gómez-López, Ana Valeria Martínez-Silva, Teresa Montiel, Daniel Osorio-Gómez, Federico Bermúdez-Rattoni, Lourdes Massieu, Diana Escalante-Alcalde
Parkinson's disease (PD) is a multifactorial neurodegenerative disorder, characterised by the progressive loss of midbrain dopaminergic neurons and a variety of motor symptoms. The gene coding for the phospholipid phosphatase 3, PLPP3 (formerly PPAP2B or LPP3), maps within the PARK10 locus, a region that has been linked with increased risk to late-onset PD. PLPP3 modulates the levels of a range of bioactive lipids controlling fundamental cellular processes within the central nervous system. Here we show that PLPP3 is enriched in astroglial cells of the adult murine ventral midbrain...
April 11, 2016: Scientific Reports
Maria S Esposito, Silvia Arber
A recent study has functionally disentangled the hitherto enigmatic mesencephalic locomotor region of the brain on the basis of cell type diversity and identified differential upstream regulatory pathways.
April 4, 2016: Current Biology: CB
Sun-Uk Lee, Hyo-Jung Kim, Jeong-Jin Park, Ji-Soo Kim
Internuclear ophthalmoplegia (INO) indicates a lesion involving the medial longitudinal fasciculus (MLF) that interconnects the abducens nucleus and medial rectus subnucleus of the oculomotor nuclear complex. In fact, rostral-caudal localization value of the INO is often limited except when it accompanies symptoms and signs owing to involvement of nearby structures. Ataxia is often observed in lesions involving the cerebellum or the fibers to and from it anywhere in the brainstem. Herein, we sought to determine the localizing value of INO plus ataxia in the rostrocaudal axis of the brainstem...
May 2016: Journal of Neurology
X Jin, K Schwabe, J K Krauss, M Alam
Loss of cholinergic neurons in the mesencephalic locomotor region, comprising the pedunculopontine nucleus (PPN) and the cuneiform nucleus (CnF), is related to gait disturbances in late stage Parkinson's disease (PD). We investigate the effect of anterior or posterior cholinergic lesions of the PPN on gait-related motor behavior, and on neuronal network activity of the PPN area and basal ganglia (BG) motor loop in rats. Anterior PPN lesions, posterior PPN lesions or sham lesions were induced by stereotaxic microinjection of the cholinergic toxin AF64-A or vehicle in male Sprague-Dawley rats...
May 13, 2016: Neuroscience
Thomas K Roseberry, A Moses Lee, Arnaud L Lalive, Linda Wilbrecht, Antonello Bonci, Anatol C Kreitzer
The basal ganglia (BG) are critical for adaptive motor control, but the circuit principles underlying their pathway-specific modulation of target regions are not well understood. Here, we dissect the mechanisms underlying BG direct and indirect pathway-mediated control of the mesencephalic locomotor region (MLR), a brainstem target of BG that is critical for locomotion. We optogenetically dissect the locomotor function of the three neurochemically distinct cell types within the MLR: glutamatergic, GABAergic, and cholinergic neurons...
January 28, 2016: Cell
Jeremy Rowe, Aijaz Khan, Charles Romanowski, Claire Isaac, Sadequate Khan, Richard Mair, Tipu Aziz, John Yianni
BACKGROUND: The pedunculopontine nucleus (PPN) is a part of the mesencephalic locomotor region and, in recent years, it has been considered a new surgical target for deep brain stimulation (DBS) for movement disorders including atypical parkinsonian syndromes such as progressive supranuclear palsy (PSP) and multiple system atrophy. Involvement of the PPN may play an important role in gait impairment in these disorders and the development of PPN DBS could potentially provide treatment for this disabling problem...
May 2016: World Neurosurgery
Nan Liang, Jere H Mitchell, Scott A Smith, Masaki Mizuno
The sympathetic and pressor responses to exercise are exaggerated in hypertension. However, the underlying mechanisms causing this abnormality remain to be fully elucidated. Central command, a neural drive originating in higher brain centers, is known to activate cardiovascular and locomotor control circuits concomitantly. As such, it is a viable candidate for the generation of the augmented vascular response to exercise in this disease. We hypothesized that augmentations in central command function contribute to the heightened cardiovascular response to exercise in hypertension...
January 1, 2016: American Journal of Physiology. Heart and Circulatory Physiology
Kaoru Takakusaki, Ryosuke Chiba, Tsukasa Nozu, Toshikatsu Okumura
The lateral part of the mesopontine tegmentum contains functionally important structures involved in the control of posture and gait. Specifically, the mesencephalic locomotor region, which may consist of the cuneiform nucleus and pedunculopontine tegmental nucleus (PPN), occupies the interest with respect to the pathophysiology of posture-gait disorders. The purpose of this article is to review the mechanisms involved in the control of postural muscle tone and locomotion by the mesopontine tegmentum and the pontomedullary reticulospinal system...
July 2016: Journal of Neural Transmission
Dimitri Ryczko, Francois Auclair, Jean-Marie Cabelguen, Réjean Dubuc
In vertebrates, stimulation of the mesencephalic locomotor region (MLR) on one side evokes symmetrical locomotor movements on both sides. How this occurs was previously examined in detail in a swimmer using body undulations (lamprey), but in tetrapods the downstream projections from the MLR to brainstem neurons are not fully understood. Here we examined the brainstem circuits from the MLR to identified reticulospinal neurons in the salamander Notophthalmus viridescens. Using neural tracing, we show that the MLR sends bilateral projections to the middle reticular nucleus (mRN, rostral hindbrain) and the inferior reticular nucleus (iRN, caudal hindbrain)...
May 1, 2016: Journal of Comparative Neurology
C Tard, A Delval, D Devos, R Lopes, P Lenfant, K Dujardin, C Hossein-Foucher, F Semah, A Duhamel, L Defebvre, F Le Jeune, C Moreau
INTRODUCTION: Freezing of gait (FoG) is a debilitating gait disorder in Parkinson's disease (PD). In advanced PD patients with FoG, the supraspinal locomotor network may be dysregulated (relative to similar patients without FoG) during gait. Here, we sought to characterize the metabolism of locomotor networks involved in FoG. METHODS: Twenty-two PD patients (11 with off-drug FoG and 11 without) each underwent two [(18)F]-fluorodeoxyglucose PET brain scans in the off-drug state: one at rest and another during radiotracer uptake while performing a standardized gait trajectory that incorporated the usual triggers for FoG...
October 29, 2015: Neuroscience
A Collomb-Clerc, M-L Welter
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and internal globus pallidus (GPi) deep brain stimulation (DBS) provides an efficient treatment for the alleviation of motor signs in patients with Parkinson's disease. The effects of DBS on gait and balance disorders are less successful and may even lead to an aggravation of freezing of gait and imbalance. The identification of a substantia nigra pars reticulata (SNr)-mesencephalic locomotor region (MLR) network in the control of locomotion and postural control and of its dysfunction/lesion in PD patients with gait and balance disorders led to suggestion that DBS should be targeting the SNr and the pedunculopontine nucleus (part of the MLR) for PD patients with these disabling axial motor signs...
November 2015: Neurophysiologie Clinique, Clinical Neurophysiology
David Sherman, Patrick M Fuller, Jacob Marcus, Jun Yu, Ping Zhang, Nancy L Chamberlin, Clifford B Saper, Jun Lu
The mesencephalic (or midbrain) locomotor region (MLR) was first described in 1966 by Shik and colleagues, who demonstrated that electrical stimulation of this region induced locomotion in decerebrate (intercollicular transection) cats. The pedunculopontine tegmental nucleus (PPT) cholinergic neurons and midbrain extrapyramidal area (MEA) have been suggested to form the neuroanatomical basis for the MLR, but direct evidence for the role of these structures in locomotor behavior has been lacking. Here, we tested the hypothesis that the MLR is composed of non-cholinergic spinally projecting cells in the lateral pontine tegmentum...
2015: Frontiers in Neurology
Peter H Weiss, Jan Herzog, Monika Pötter-Nerger, Daniela Falk, Hans Herzog, Günther Deuschl, Jens Volkmann, Gereon R Fink
BACKGROUND: Subthalamic deep brain stimulation (STN-DBS) can ameliorate gait disturbances in Parkinson's disease (PD). Using motor imagery and positron emission tomography (PET), we investigated how STN-DBS interacts with supraspinal locomotor centers in PD. METHODS: Ten PD patients with bilateral STN-DBS actually walked or stood still under STN-DBS ON or OFF conditions. Directly thereafter, subjects imagined walking or standing while changes in regional cerebral blood flow were measured by PET...
July 2015: Movement Disorders: Official Journal of the Movement Disorder Society
C W MacDonell, K E Power, J W Chopek, K R Gardiner, P F Gardiner
This study examined motoneurone properties during fictive locomotion in the adult rat for the first time. Fictive locomotion was induced via electrical stimulation of the mesencephalic locomotor region in decerebrate adult rats under neuromuscular blockade to compare basic and rhythmic motoneurone properties in antidromically identified extensor motoneurones during: (1) quiescence, before and after fictive locomotion; (2) the 'tonic' period immediately preceding locomotor-like activity, whereby the amplitude of peripheral flexor (peroneal) and extensor (tibial) nerves are increased but alternation has not yet occurred; and (3) locomotor-like episodes...
May 15, 2015: Journal of Physiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"