Direct and relayed projection of periodontal receptor afferents to the cerebellum in the ferret

1987 ◽  
Vol 231 (1263) ◽  
pp. 199-216 ◽  
Keyword(s):  
Cerebellar Cortex ◽  
Evidence Based ◽  
Field Potentials ◽  
Muscle Spindle Afferents ◽  
Latency Analysis ◽  
Jaw Muscle ◽  
To Come ◽  
Periodontal Afferent ◽  
Mossy Fibres ◽  
Stimulation Of

Field potentials in the cerebellar cortex of the ferret have been studied in response to stimulation of alveolar, muscular and cutaneous branches of the trigeminal nerve. Responses from the alveolar nerves are unusual in their very short latency. Evidence based on latency analysis, frequency following and comparison with other well-known inputs supports the view that the earliest field potentials are due to direct, unrelayed afferents, which terminate as mossy fibres. There is, in addition, a monosynaptically relayed afferent path via mossy fibres. The alveolar nerve afferents concerned with the direct projection are shown to come from periodontal mechanoreceptors and not from cutaneous receptors. No such connections are found from jaw-muscle spindle afferents. The direct and relayed periodontal pathways are both ipsilateral and crossed. They terminate in the cerebellar cortex in the parvermal region of lobules IV, V and VI. The functional significance of the direct periodontal afferent projection is considered particularly in the light of parallels with the vestibular system, which also has direct and relayed cerebellar projections.

Reflex Responses in Human Jaw, Lip, and Tongue Muscles Elicited by Mechanical Stimulation

1987 ◽  
Vol 30 (1) ◽  
pp. 70-79 ◽  
Author(s):  
Christine M. Weber ◽  
Anne Smith
Keyword(s):  
Mechanical Stimuli ◽  
Observable Effect ◽  
Direct Stimulation ◽  
Muscle Spindle Afferents ◽  
Lower Lip ◽  
Reflex Responses ◽  
Reflex Pathways ◽  
Tongue Muscles ◽  
Jaw Muscle ◽  
Stimulation Of

Reflex responses in human jaw, lip, and tongue muscles were elicited with brief, innocuous mechanical stimuli. Stimuli were applied to the masseter (and overlying tissue), the lower lip vermilion, and the tongue dorsum. Reflex responses occurred in masseter, orbicularis oris inferior, and genioglossus muscles upon direct stimulation of the sites associated with each of these muscles. In contrast, reflex responses to stimulation of "distant" sites occurred almost exclusively in masseter; that is, stimulation of the lip and tongue produced responses in masseter, but, stimulation of jaw muscle spindle afferents and overlying cutaneous receptors had no observable effect on activity in genioglossus or orbicularis oris inferior muscles. It could be hypothesized that the motoneuron pools controlling jaw muscles are more sensitive to synaptic inputs generated by reflex pathways originating in other structures. The sensitivity of the masseter muscle to inputs from the lip and tongue may serve to link these structures functionally.

Localization in the Cerebellar Hemisphere of Climbing-Fiber Responses Evoked from the Trigeminal Nerve in the Cat

1974 ◽  
Vol 52 (6) ◽  
pp. 1147-1153 ◽  
Author(s):  
T. S. Miles ◽  
J. D. Cooke ◽  
M. Wiesendanger
Keyword(s):  
Purkinje Cells ◽  
Cerebellar Cortex ◽  
Anterior Lobe ◽  
Cerebellar Hemisphere ◽  
Projection Area ◽  
Field Potentials ◽  
Facial Skin ◽  
Almost All ◽  
Climbing Fiber Responses ◽  
Stimulation Of

The area of cerebellar cortex to which climbing fibers (CF) project from trigeminal cutaneous afferents has been established in pentobarbital-anesthetized cats. This area is centered upon the ipsilateral lobule HVI, with some overlap onto adjoining folia of the anterior lobe (lobule V) and onto crus Ia of lobule HVIIA. At almost all points within the projection area, CF field potentials of various amplitudes could be elicited by stimulation of more than one trigeminal branch. Hence the general somatotopic arrangement was a complex pattern of inputs converging onto many points from spatially related areas of facial skin. Convergence from more than one nerve was also seen on 32 of 47 single Purkinje cells.

scholarly journals Cerebellar implementation of movement sequences through feedback

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Andrei Khilkevich ◽  
Juan Zambrano ◽  
Molly-Marie Richards ◽  
Michael Dean Mauk
Keyword(s):  
Purkinje Cells ◽  
Cerebellar Cortex ◽  
General Framework ◽  
Eyelid Conditioning ◽  
Mossy Fibers ◽  
Learning Processes ◽  
Single Component ◽  
Associate Learning ◽  
Stimulation Of

Most movements are not unitary, but are comprised of sequences. Although patients with cerebellar pathology display severe deficits in the execution and learning of sequences (Doyon et al., 1997; Shin and Ivry, 2003), most of our understanding of cerebellar mechanisms has come from analyses of single component movements. Eyelid conditioning is a cerebellar-mediated behavior that provides the ability to control and restrict inputs to the cerebellum through stimulation of mossy fibers. We utilized this advantage to test directly how the cerebellum can learn a sequence of inter-connected movement components in rabbits. We show that the feedback signals from one component are sufficient to serve as a cue for the next component in the sequence. In vivo recordings from Purkinje cells demonstrated that all components of the sequence were encoded similarly by cerebellar cortex. These results provide a simple yet general framework for how the cerebellum can use simple associate learning processes to chain together a sequence of appropriately timed responses.

Evoked potentials elicited on the cerebellar cortex by electrical stimulation of the rat spinocerebellar tract

2009 ◽  
Vol 72 (4) ◽  
pp. 395-400 ◽  
Author(s):  
Hiroyuki Muramatsu ◽  
Kyouichi Suzuki ◽  
Tatsuya Sasaki ◽  
Masato Matsumoto ◽  
Jun Sakuma ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Evoked Potentials ◽  
Cerebellar Cortex ◽  
Spinocerebellar Tract ◽  
Stimulation Of

Reversibility of Ia EPSP investigated with intracellularly iontophoresed QX-222

1982 ◽  
Vol 48 (2) ◽  
pp. 419-430 ◽  
Author(s):  
J. A. Flatman ◽  
I. Engberg ◽  
J. D. Lambert
Keyword(s):  
Action Potential ◽  
Muscle Afferents ◽  
Field Potentials ◽  
Potential Generation ◽  
Action Potential Firing ◽  
Hindlimb Muscle ◽  
Potential Firing ◽  
Ia Epsp ◽  
High Conductance ◽  
Stimulation Of

1. Cat lumbosacral motoneurons were impaled by two individually advanced microelectrodes: one to record membrane potential (EM), the second to pass depolarizing currents. 2. During the passage of depolarizing current ramps the repetitive action-potential firing and the later high conductance (GM) state obscured and distorted Ia excitatory postsynaptic potentials (EPSPs) evoked by electrical stimulation of hindlimb muscle afferents. 3. Intracellular iontophoresis of QX-222 (a trimethyl analogue of lignocaine) or methylxylocholine, prevented action-potential generation and reduced the GM increase during current depolarization so that positive levels of EM could be reached. 4. Following QX-222 treatment it was possible to demonstrate a reversal of the Ia EPSP including its first part, at EM values between -13 and +32 mV. Reversal was seen in 13 of the 22 motoneurons tested. 5. Reversal was easiest to obtain in motoneurons of the deep peroneal group. More positive levels of EM were needed to show a reversal in neurons of the gastrocnemius-so-leus group. (The 10-90% rise times of the EPSPs were rather similar for both groups.) 6. In a few motoneurons the initial part of the Ia EPSP reversed at a more negative EM than a later part. This was best seen after subtraction of the extracellular field potentials from the records.

scholarly journals “They Just Need to Come Down a Little Bit to Your Level”: A Qualitative Study of Parents’ Views and Experiences of Early Life Interventions to Promote Healthy Growth and Associated Behaviours

2020 ◽  
Vol 17 (10) ◽  
pp. 3605
Author(s):  
Marita Hennessy ◽  
Molly Byrne ◽  
Rachel Laws ◽  
Caroline Heary
Keyword(s):  
Health Professionals ◽  
Early Life ◽  
Critical Time ◽  
Evidence Based ◽  
Structured Interviews ◽  
Critical Window ◽  
Time Period ◽  
Multi Level ◽  
To Come ◽  
Healthy Growth

The first 1000 days is a critical window of opportunity to promote healthy growth and associated behaviours. Health professionals can play an important role, in part due to the large number of routine contacts they have with parents. There is an absence of research on the views of parents towards obesity prevention and the range of associated behaviours during this time period. This study aimed to elicit parents’ views on early life interventions to promote healthy growth/prevent childhood obesity, particularly those delivered by health professionals. Semi-structured interviews were conducted with 29 parents (24 mothers, 5 fathers) who were resident in Ireland and had at least one child aged under 30 months. Data were analysed using reflexive thematic analysis. Two central themes were generated: (1) navigating the uncertainty, stress, worries, and challenges of parenting whilst under scrutiny and (2) accessing support in the broader system. Parents would welcome support during this critical time period; particularly around feeding. Such support, however, needs to be practical, realistic, evidence-based, timely, accessible, multi-level, non-judgemental, and from trusted sources, including both health professionals and peers. Interventions to promote healthy growth and related behaviours need to be developed and implemented in a way that supports parents and their views and circumstances.

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