scholarly journals Eyelid Opening with Trigeminal Proprioceptive Activation Regulates a Brainstem Arousal Mechanism

PLoS ONE ◽  
2015 ◽  
Vol 10 (8) ◽  
pp. e0134659 ◽  
Author(s):  
Kiyoshi Matsuo ◽  
Ryokuya Ban ◽  
Yuki Hama ◽  
Shunsuke Yuzuriha
Keyword(s):  
Arousal Mechanism

Arousing the LTP and learning debate

1997 ◽  
Vol 20 (4) ◽  
pp. 622-623 ◽  
Author(s):  
Stephen Maren
Keyword(s):  
Learning And Memory ◽  
Long Term Potentiation ◽  
Term Potentiation ◽  
Arousal Mechanism

Shors & Matzel provide compelling arguments against a role for hippocampal long-term potentiation (LTP) in mammalian learning and memory. As an alternative, they suggest that LTP is an arousal mechanism. I will argue that this view is not a satisfactory alternative to current conceptions of LTP function.

Characterization of midbrain component of the trigger for arousal from hibernation

1976 ◽  
Vol 230 (2) ◽  
pp. 368-375 ◽  
Author(s):  
AL Beckman ◽  
E Satinoff ◽  
TL Stanton
Keyword(s):  
Body Temperature ◽  
Ambient Temperature ◽  
Reticular Formation ◽  
Functional Organization ◽  
Ground Squirrels ◽  
Anterior Hypothalamus ◽  
Midbrain Reticular Formation ◽  
Citellus Lateralis ◽  
Arousal Mechanism

The ability of the midbrain reticular formation (MRF) to trigger arousal from hibernation and to change body temperature (Tb) during euthermia was tested in golden-mantled ground squirrels (Citellus lateralis). During hibernation (ambient temperature 5-6 degrees C) microinjections of cholinomimetic compounds (acetylcholine and carbachol) triggered full arousal or produced transient increases in Tb in 15 out of 19 tests; MRF microinjections of norepinephrine (NE) and 5-hydroxytryptamine (5-HT), at the same concentrations that produced full arousal when microinjected into the preoptic/anterior hypothalamus (PO/AH) area in previous experiments, has no effect on Tb in 13 out of 16 tests. In experiments on euthermic ground squirrels tested at an ambient temperature of 25 degrees C, MRF microinjections of acetylcholine raised Tb, whereas the monoamines had no significant effects. These results show that cholinoceptive neurons in the MRF can trigger arousal from hibernation and increase Tb during euthermia. The failure of NE and 5-HT to produce any significant effects at the same doses that were reported to be effective in the PO/AH indicates that the functional organization of the MRF portion of the arousal mechanism is different from that reported for the PO/AH.

Identified octopaminergic neurons provide an arousal mechanism in the locust brain

1995 ◽  
Vol 74 (6) ◽  
pp. 2739-2743 ◽  
Author(s):  
J. P. Bacon ◽  
K. S. Thompson ◽  
M. Stern
Keyword(s):  
Action Potentials ◽  
Tactile Stimulation ◽  
Neural Circuit ◽  
Optic Lobe ◽  
Repetitive Stimulation ◽  
Movement Detector ◽  
Optic Lobes ◽  
Tactile Stimuli ◽  
Arousal Mechanism ◽  
Contralateral Movement

1. Habituation is the declining responsiveness of a neural circuit (or behavior) to repetitive stimulation. Dishabituation (or arousal) can be brought about by the sudden presentation of an additional, novel stimulus. A clear example of arousal in the locust is provided by the visual system: the habituated response of the descending contralateral movement detector (DCMD) interneuron to repetitive visual stimuli can be dishabituated by a variety of other visual and tactile stimuli. 2. Application of octopamine to the locust brain and optic lobes dishabituates the DCMD in a manner similar to the effect of visual and tactile stimulation. 3. The locust CNS contains two pairs of octopamine-immunoreactive cells, the protocerebral medulla 4 (PM4) neurons, that could potentially mediate this dishabituation effect; PM4 neurons arborize in the optic lobe, they contain octopamine, and they respond to the same visual and tactile stimuli that dishabituate the DCMD. 4. To investigate whether PM4 activity dishabituates the DCMD, we recorded intracellularly from one of the PM4 neurons while recording extracellularly from the DCMD. When the PM4 neuron is injected with hyperpolarizing current to render it completely inactive, the DCMD exhibits its characteristic habituation to a moving visual stimulus. However, depolarizing the PM4 neuron, to produce action potentials at approximately 20 Hz, significantly increases the number of DCMD action potentials per stimulus. 5. The PM4 neurons may therefore play an important role in dishabituating the DCMD to novel stimuli. This effect is presumably mediated by PM4 neurons releasing endogenous octopamine within the optic lobe.

scholarly journals Multimodal Sensory Responses of Nucleus Reticularis Gigantocellularis and the Responses' Relation to Cortical and Motor Activation

2010 ◽  
Vol 103 (5) ◽  
pp. 2326-2338 ◽  
Author(s):  
Eugene M. Martin ◽  
Constantine Pavlides ◽  
Donald Pfaff
Keyword(s):  
Reticular Formation ◽  
Neck Muscle ◽  
Medullary Reticular Formation ◽  
Nucleus Reticularis ◽  
Nucleus Reticularis Gigantocellularis ◽  
Arousal Mechanism ◽  
Sensory Responses ◽  
Excitatory Responses ◽  
Fast Oscillations ◽  
Large Neurons

The connectivity of large neurons of the nucleus reticularis gigantocellularis (NRGc) in the medullary reticular formation potentially allows both for the integration of stimuli, in several modalities, that would demand immediate action, and for coordinated activation of cortical and motoric activity. We have simultaneously recorded cortical local field potentials, neck muscle electromyograph (EMG), and the neural activity of medullary NRGc neurons in unrestrained, unanesthetized rats to determine whether the activity of the NRGc is consistent with the modulation of general arousal. We observed excitatory responses of individual NRGc neurons to all modalities tested: tactile, visual, auditory, vestibular, and olfactory. Excitation was directly linked to increases in neck muscle EMG amplitude and corresponded with increases in the power of fast oscillations (30 to 80 Hz) of cortical activity and decreases in the power of slow oscillations (2 to 8 Hz). Because these reticular formation neurons can respond to broad ranges of stimuli with increased firing rates associated with the initiation of behavioral responses, we infer that they are part of an elementary “first responder” CNS arousal mechanism.

scholarly journals From relativistic time dilation to psychological time perception: an approach and model, driven by the theories of relativity, to calculate the time perceived while experiencing different situations.

2019 ◽  
Author(s):  
Andrea Conte
Keyword(s):  
Time Perception ◽  
Time Dilation ◽  
Point Of View ◽  
Model Driven ◽  
Relativistic Time ◽  
Time Correlations ◽  
Arousal Mechanism ◽  
Energy Ratios ◽  
Dilation Equations ◽  
Relativistic View

A model, driven by the Einstein's theories of relativity, is suggested. This model tends to correlate the relativistic view on time dilation with the current models and conclusions on time perception. The model uses energy ratios instead of geometrical transformations to approach and express time dilation. Brain mechanisms like the arousal mechanism and the attention mechanism are interpreted and combined. Matrices of order two are generated to contain the time dilation between two observers, from the point of view of a third observer. The matrices are used to transform an observer time to another observer time. Correlations with the official time dilation equations are given in the appendix.

scholarly journals The Influence of Emotional Awareness on Time Perception: Evidence From Event-Related Potentials

2021 ◽  
Vol 12 ◽  
Author(s):  
Jia Ma ◽  
Jiamei Lu ◽  
Xu Li
Keyword(s):  
Time Perception ◽  
Positive Emotion ◽  
Negative Emotion ◽  
Event Related Potentials ◽  
Emotional Awareness ◽  
Event Related Potential ◽  
Time Duration ◽  
Arousal Mechanism ◽  
Related Potentials ◽  
Emotional Pictures

Prior studies found that participants overestimated both negative and positive emotional stimuli, compared with neutral emotion. This phenomenon can be explained by the “arousal mechanism.” Participants demonstrated individual differences in emotion perception. In other words, high emotional awareness resulted in high emotional arousal, and vice versa. This study extended existing findings by exploring the influence of emotional awareness on time perception in a temporal generalization task, while recording electroencephalographic (EEG) signals. The findings revealed that in the positive emotion condition, the high emotional awareness group made more overestimations, compared with the low emotional awareness group. However, no difference was observed in the neutral or negative emotion conditions. Moreover, the event-related potential (ERP) results showed that in the positive emotion condition, the high awareness group elicited larger vertex positive potential (VPP) amplitudes, compared with that of the low awareness group. However, no such differences were observed in the neutral and negative emotion conditions. Moreover, the contingent negative variation (CNV) (200–300, 300–490 ms) component showed that in the positive emotion, the amplitudes of the high awareness group were larger than that of the low awareness group; however, they did not show differences in the neutral condition. The findings of this study suggest that high emotional awareness produces higher physiological arousal; moreover, when participants were required to estimate the time duration of emotional pictures, they tended to make higher time overestimation. Thus, our results support the relationship between emotional awareness and time perception.

scholarly journals Physiopathogenetic Interrelationship between Nocturnal Frontal Lobe Epilepsy and NREM Arousal Parasomnias

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Péter Halász ◽  
Anna Kelemen ◽  
Anna Szűcs
Keyword(s):  
Frontal Lobe ◽  
Nrem Sleep ◽  
Absence Epilepsy ◽  
Published Data ◽  
Nocturnal Frontal Lobe Epilepsy ◽  
Common Features ◽  
Arousal System ◽  
Epileptic Disorder ◽  
Arousal Mechanism ◽  
State Dissociation

Aims. To build up a coherent shared pathophysiology of NFLE and AP and discuss the underlying functional network. Methods. Reviewing relevant published data we point out common features in semiology of events, relations to macro- and microstructural dynamism of NREM sleep, to cholinergic arousal mechanism and genetic aspects. Results. We propose that pathological arousals accompanied by confused behavior with autonomic signs and/or hypermotor automatisms are expressions of the frontal cholinergic arousal function of different degree, during the condition of depressed cognition by frontodorsal functional loss in NREM sleep. This may happen either if the frontal cortical Ach receptors are mutated in ADNFLE (and probably also in genetically not proved nonlesional cases as well), or without epileptic disorder, in AP, assuming gain in receptor functions in both conditions. This hypothesis incorporates the previous “liberation theory” of Tassinari and the “state dissociation hypothesis” of Bassetti and Terzaghi). We propose that NFLE and IGE represent epileptic disorders of the two antagonistic twin systems in the frontal lobe. NFLE is the epileptic facilitation of the ergotropic frontal arousal system whereas absence epilepsy is the epileptic facilitation of burst-firing working mode of the spindle and delta producing frontal thalamocortical throphotropic sleep system. Significance. The proposed physiopathogenesis conceptualize epilepsies in physiologically meaningful networks.

The Charles Bonnet Syndrome: ‘Phantom Visual Images’

Perception ◽  
1991 ◽  
Vol 20 (6) ◽  
pp. 809-825 ◽  
Author(s):  
Geoffrey Schultz ◽  
Ronald Melzack
Keyword(s):  
Visual Experience ◽  
Sensory Deprivation ◽  
Emotional Reaction ◽  
Sensory Loss ◽  
Visual Images ◽  
Charles Bonnet Syndrome ◽  
Number Of Factors ◽  
Arousal Mechanism ◽  
Syndrome Individual ◽  
The Brain

The Charles Bonnet syndrome is a condition in which individuals experience complex visual hallucinations without demonstrable psychopathology or disturbance of normal consciousness. An analysis of the sixty-four cases described in the literature reveals that the syndrome can occur at any age though it is more common in elderly people. Reduction in vision, due to peripheral eye pathology as well as pathology within the brain, is associated with the syndrome. Individual hallucinatory episodes can last from a few seconds to most of the day. Episodes can occur for periods of time ranging from days to years, with the hallucinations changing both in frequency and in complexity during this time. The hallucinations may be triggered or stopped by a number of factors which may exert their effect through a general arousal mechanism. People, animals, buildings, and scenery are reported most often. These images may appear static, moving in the visual field, or animated. Emotional reaction to the hallucinations may be positive or negative. Several theories have been proposed to account for the hallucinations. This paper highlights the sensory deprivation framework, with particular emphasis on the activity in the visual system after sensory loss that produces patterns of nerve impulses that, in turn, give rise to visual experience.

Long-term potentiation: Does it deserve attention?

1997 ◽  
Vol 20 (4) ◽  
pp. 625-626
Author(s):  
Shane M. O'Mara ◽  
Sean Commins ◽  
Colin Gemmell ◽  
John Gigg
Keyword(s):  
Hippocampal Neurons ◽  
Long Term Potentiation ◽  
Memory Storage ◽  
Storage Mechanism ◽  
Term Potentiation ◽  
Target Article ◽  
Arousal Mechanism

Shors & Matzel's target article is a thought-provoking attempt to reconceptualise long-term potentiation as an attentional or arousal mechanism rather than a memory storage mechanism. This is incompatible with the facts of the neurobiology of attention and of the behavioural neurophysiological properties of hippocampal neurons.

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