Spatial relationships between the terminations of somatic sensory motor pathways in the rostral brainstem of cats and monkeys. II. Cerebellar projections compared with those of the ascending somatic sensory pathways in lateral diencephalon

1983 ◽  
Vol 220 (2) ◽  
pp. 229-251 ◽  
Author(s):  
Karen J. Berkley
Keyword(s):  
Spatial Relationships ◽  
Motor Pathways ◽  
Sensory Pathways ◽  
Sensory Motor

Neurology

2017 ◽  
Author(s):  
Mark Harrison
Keyword(s):  
Emergency Medicine ◽  
Intracranial Pressure ◽  
Auditory System ◽  
Nerve Conduction ◽  
Motor Pathways ◽  
Sensory Pathways ◽  
Neurological System

This chapter describes the pathophysiology of the neurological system as it applies to Emergency Medicine, and in particular the Primary FRCEM examination. The chapter outlines the key details of intracranial pressure, sensory pathways, motor pathways, nerve conduction, pain, sight, auditory system, brainstem reflexes, and temperature. This chapter is laid out exactly following the RCEM syllabus, to allow easy reference and consolidation of learning.

scholarly journals Multiple Sensory-Motor Pathways Lead to Coordinated Visual Attention

2016 ◽  
Vol 41 ◽  
pp. 5-31 ◽  
Author(s):  
Chen Yu ◽  
Linda B. Smith
Keyword(s):  
Visual Attention ◽  
Motor Pathways ◽  
Sensory Motor

scholarly journals E. coli chemotaxis is information-limited

2021 ◽  
Author(s):  
H.H. Mattingly ◽  
K. Kamino ◽  
B.B. Machta ◽  
T. Emonet
Keyword(s):  
Escherichia Coli ◽  
Information Acquisition ◽  
Environmental Information ◽  
Behavioral Performance ◽  
Theoretical Limit ◽  
Acquisition Rate ◽  
Motor Pathways ◽  
E Coli ◽  
Sensory Motor

AbstractOrganisms must acquire and use environmental information to guide their behaviors. However, it is unclear whether and how information quantitatively limits behavioral performance. Here, we relate information to behavioral performance in Escherichia coli chemotaxis. First, we derive a theoretical limit for the maximum achievable gradient-climbing speed given a cell’s information acquisition rate. Next, we measure cells’ gradient-climbing speeds and the rate of information acquisition by the chemotaxis pathway. We find that E. coli make behavioral decisions with much less than the 1 bit required to determine whether they are swimming up-gradient. However, they use this information efficiently, performing near the theoretical limit. Thus, information can limit organisms’ performance, and sensory-motor pathways may have evolved to efficiently use information from the environment.

scholarly journals Intraoperative neuromonitoring in spine deformity surgery: modalities, advantages, limitations, medicolegal issues – surgeons’ views

2020 ◽  
Vol 5 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Mirza Biscevic ◽  
Aida Sehic ◽  
Ferid Krupic
Keyword(s):  
Spinal Cord ◽  
Evoked Potentials ◽  
Motor Evoked Potentials ◽  
Dorsal Column ◽  
Intraoperative Neuromonitoring ◽  
Spine Deformity ◽  
Medial Lemniscus ◽  
Motor Pathways ◽  
Sensory Pathways ◽  
Permanent Neurological Deficit

In spine deformity surgery, iatrogenic neurologic injuries might occur due to the mechanical force applied to the spinal cord from implants, instruments, and bony structures, or due to ischemic changes from vessel ligation during exposure and cord distraction/compression during corrective manoeuvres. Prompt reaction within the reversible phase (reducing of compressive/distractive forces) usually restores functionality of the spinal cord, but if those forces continue to persist, a permanent neurological deficit might be expected. With monitoring of sensory pathways (dorsal column–medial lemniscus) by somatosensory-evoked potentials (SSEPs), such events are detected with a sensitivity of up to 92%, and a specificity of up to 100%. The monitoring of motor pathways by transcranial electric motor-evoked potentials (TceMEPs) has a sensitivity and a specificity of up to 100%, but it requires avoidance of halogenated anaesthetics and neuromuscular blockades. Different modalities of intraoperative neuromonitoring (IONM: SSEP, TceMEP, or combined) can be performed by the neurophysiologist, the technician or the surgeon. Combined SSEP/TceMEP performed by the neurophysiologist in the operating room is the preferable method of IONM, but it might be impractical or unaffordable in many institutions. Still, many spine deformity surgeries worldwide are performed without any type of IONM. Medicolegal aspects of IONM are different worldwide and in many cases some vagueness remains. The type of IONM that a spinal surgeon employs should be reliable, affordable, practical, and recognized by the medicolegal guidelines. Cite this article: EFORT Open Rev 2020;5:9-16. DOI: 10.1302/2058-5241.5.180032

Major sensory and motor systems

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Nervous System ◽  
Cerebral Cortex ◽  
No Value ◽  
Cranial Nerves ◽  
Sensory Information ◽  
The Body ◽  
Functional Responses ◽  
Motor Pathways ◽  
Sensory Pathways ◽  
And Function

The previous chapter provided an overview of the anatomy of the CNS, concentrating on structures that can be seen during dissection of the human brain and spinal cord or the study of anatomical models of these structures. Some indication of the function of different components of the CNS has been given in Chapter 15, but this chapter shows how the various anatomical components of the CNS are functionally linked together through sensory and motor pathways. These pathways enable the nervous system to convey information over considerable distances, to integrate the information, and formulate functional responses that coordinate activities of different parts of the body. It will be necessary to introduce some other structures in addition to those described in Chapter 15 during the description of major pathways; most are not visible to the naked eye and even when seen in microscopical sections, they require considerable practice to distinguish them. However, they are important landmarks or relay stations in the central nervous pathways and you need to know of them for a full understanding of pathways. As emphasized in Chapter 14, our views of the structure and function of many aspects of the nervous system are constantly subject to revision in the light of new clinical and experimental observations and methods of investigation. This applies to nerve pathways just as much as any other aspect of the nervous system. This chapter presents a summary of current views on somatic sensory and motor functions and their application to the practice of dentistry. The special sensory pathways of olfaction, vision, and hearing are described in Chapter 18 in the context of the cranial nerves that form the first part of these pathways. The information conveyed from the periphery by the sensory components of spinal and cranial nerves is destined to reach the cerebral cortex or the cerebellum. You will be conscious of sensory information that reaches the cerebral cortex, but mostly unaware of information that does not travel to the cortex. However, this does not mean that sensory information that does not attain cortical levels is of no value. For example, sensory neurons or their collateral processes form the afferent limbs of many reflex arcs.

Stuttering

1981 ◽  
Vol 24 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Gerald N. Zimmermann ◽  
Anne Smith ◽  
John M. Hanley
Keyword(s):  
Motor Control ◽  
Motor Pathways ◽  
Physiological Variables ◽  
Control Processes ◽  
Sensory Motor ◽  
Muscle Groups ◽  
Similar Motor ◽  
Therapeutic Considerations

Perceptually fluent and disfluent speech reflect a continuum of coordination and can be best understood in terms of similar motor control processes. Speech movements may be considered to result from the interaction of inputs to motoneuron pools which alter the tuning of sensory-motor pathways and triggering inputs to specific muscles and muscle groups. A disorder in coordination may occur when any of these inputs is aberrantly affected by psychological, psychosocial or physiological variables. Specific phenomena associated with stuttering--adaptation, masking, whispering and voicing deviations--are interpreted in terms of these neuromotor processes. Therapeutic considerations are discussed.

scholarly journals Network analysis of mesoscale mouse brain structural connectome yields modular structure that aligns with anatomical regions and sensory pathways

2019 ◽  
Author(s):  
Bernard A. Pailthorpe
Keyword(s):  
Mouse Brain ◽  
3D Visualization ◽  
Visual Complexity ◽  
Network Models ◽  
Structural Features ◽  
Biologically Relevant ◽  
Sensory Pathways ◽  
Structural Connectome ◽  
Sensory Motor ◽  
Cortical Association Areas

AbstractThe Allen mesoscale mouse brain structural connectome is analysed using standard network methods combined with 3D visualizations. The full region-to-region connectivity data is used, with a focus on the strongest structural links. The spatial embedding of links and time evolution of signalling is incorporated, with two-step links included. Modular decomposition using the Infomap method produces 8 network modules that correspond approximately to major brain anatomical regions and system functions. These modules align with the anterior and posterior primary sensory systems and association areas. 3D visualization of network links is facilitated by using a set of simplified schematic coordinates that reduces visual complexity. Selection of key nodes and links, such as sensory pathways and cortical association areas together reveal structural features of the mouse structural connectome consistent with biological functions in the sensory-motor systems, and selective roles of the anterior and posterior cortical association areas of the mouse brain. Time progression of signals along sensory pathways reveals that close links are to local cortical association areas and cross modal, while longer links provide anterior-posterior coordination and inputs to non cortical regions. The fabric of weaker links generally are longer range with some having brain-wide reach. Cortical gradients are evident along sensory pathways within the structural network.Author’s SummaryNetwork models incorporating spatial embedding and signalling delays are used to investigate the mouse structural connectome. Network models that include time respecting paths are used to trace signaling pathways and reveal separate roles of shorter vs. longer links. Here computational methods work like experimental probes to uncover biologically relevant features. I use the Infomap method, which follows random walks on the network, to decompose the directed, weighted network into 8 modules that align with classical brain anatomical regions and system functions. Primary sensory pathways and cortical association areas are separated into individual modules. Strong, short range links form the sensory-motor paths while weaker links spread brain-wide, possibly coordinating many regions.

Plasticity of Synaptic Connections in Sensory-Motor Pathways of the Adult Locust Flight System

1997 ◽  
Vol 78 (3) ◽  
pp. 1276-1284 ◽  
Author(s):  
Harald Wolf ◽  
Ansgar Büschges
Keyword(s):  
Electric Stimulation ◽  
Motor Pattern ◽  
Competitive Interactions ◽  
Synaptic Connections ◽  
Flight System ◽  
Motor Pathways ◽  
Synaptic Contacts ◽  
Locust Flight ◽  
Sensory Motor ◽  
Adult Locust

Wolf, Harald and Ansgar Büschges. Plasticity of synaptic connections in sensory-motor pathways of the adult locust flight system. J. Neurophysiol. 78: 1276–1284, 1997. We investigated possible roles of retrograde signals and competitive interactions in the lesion-induced reorganization of synaptic contacts in the locust CNS. Neuronal plasticity is elicited in the adult flight system by removal of afferents from the tegula, a mechanoreceptor organ at the base of the wing. We severed one hindwing organ and studied the resulting rearrangement of synaptic contacts between flight interneurons and afferent neurons from the remaining three tegulae (2 forewing, 1 hindwing). This was done by electric stimulation of afferents and intracellular recording from interneurons (and occasionally motoneurons). Two to three weeks after unilateral tegula lesion, connections between tegula afferents and flight interneurons were altered in the following way. 1) Axons from the forewing tegula on the operated side had established new synaptic contacts with metathoracic elevator interneurons. In addition, the amplitude of compound excitatory postsynaptic potentials elicited by electric stimulation was increased, indicating that a larger number of afferents connected to any given interneuron. 2) On the side contralateral to the lesion, connectivity between axons from the forewing tegula and elevator interneurons was decreased. 3) The efficacy of the (remaining) hindwing afferents appeared to be increased with regard to both synaptic transmission to interneurons and impact on flight motor pattern. 4) Flight motoneurons, which are normally restricted to the ipsilateral hemiganglion, sprouted across the ganglion midline after unilateral tegula removal and apparently established new synaptic contacts with tegula afferents on that side. The changes on the operated side are interpreted as occupation of synaptic space vacated on the interneurons by the severed hindwing afferents. On the contralateral side, the changes in synaptic contact must be elicited by retrograde signals from bilaterally arborizing flight interneurons, because tegula projections remain strictly ipsilateral. The pattern of changes suggests competitive interactions between forewing and hindwing afferents. The present investigation thus presents evidence that the CNS of the mature locust is capable of extensive synaptic rearrangement in response to injury and indicates for the first time the action of retrograde signals from interneurons.

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