scholarly journals Rapid development of strong, persistent, spatiotemporally extensive cortical synchrony and underlying oscillations following acute MCA focal ischemia

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ellen G. Wann ◽  
Anirudh Wodeyar ◽  
Ramesh Srinivasan ◽  
Ron D. Frostig
Keyword(s):  
Neuronal Activity ◽  
Rat Model ◽  
Microelectrode Array ◽  
Rapid Development ◽  
Similar Frequency ◽  
Electrophysiological Recordings ◽  
Ischemic Period ◽  
Spatiotemporal Analyses ◽  
Eeg Recordings ◽  
Evoked Activity

AbstractStroke is a leading cause of death and the leading cause of long-term disability, but its electrophysiological basis is poorly understood. Characterizing acute ischemic neuronal activity dynamics is important for understanding the temporal and spatial development of ischemic pathophysiology and determining neuronal activity signatures of ischemia. Using a 32-microelectrode array spanning the depth of cortex, electrophysiological recordings generated for the first time a continuous spatiotemporal profile of local field potentials (LFP) and multi-unit activity (MUA) before (baseline) and directly after (0–5 h) distal, permanent MCA occlusion (pMCAo) in a rat model. Although evoked activity persisted for hours after pMCAo with minor differences from baseline, spatiotemporal analyses of spontaneous activity revealed that LFP became spatially and temporally synchronized regardless of cortical depth within minutes after pMCAo and extended over large parts of cortex. Such enhanced post-ischemic synchrony was found to be driven by increased bursts of low multi-frequency oscillations and continued throughout the acute ischemic period whereas synchrony measures minimally changed over the same recording period in surgical sham controls. EEG recordings of a similar frequency range have been applied to successfully predict stroke damage and recovery, suggesting clear clinical relevance for our rat model.

scholarly journals Dynamic fMRI and EEG Recordings during Spike-Wave Seizures and Generalized Tonic-Clonic Seizures in WAG/Rij Rats

2004 ◽  
Vol 24 (6) ◽  
pp. 589-599 ◽  
Author(s):  
Hrachya Nersesyan ◽  
Fahmeed Hyder ◽  
Douglas L. Rothman ◽  
Hal Blumenfeld
Keyword(s):  
Somatosensory Cortex ◽  
Neuronal Activity ◽  
Epileptic Seizures ◽  
Occipital Cortex ◽  
Blood Oxygen Level Dependent ◽  
Blood Oxygen Level ◽  
Electrophysiological Recordings ◽  
Clonic Seizures ◽  
Eeg Recordings ◽  
Spike Wave

Generalized epileptic seizures produce widespread physiological changes in the brain. Recent studies suggest that “generalized” seizures may not involve the whole brain homogeneously. For example, electrophysiological recordings in WAG/Rij rats, an established model of human absence seizures, have shown that spike-and-wave discharges are most intense in the perioral somatosensory cortex and thalamus, but spare the occipital cortex. Is this heterogeneous increased neuronal activity matched by changes in local cerebral blood flow sufficient to meet or exceed cerebral oxygen consumption? To investigate this, we performed blood oxygen level-dependent functional magnetic resonance imaging (fMRI) measurements at 7T with simultaneous electroencephalogram recordings. During spontaneous spike-wave seizures in WAG/Rij rats under fentanylhaloperidol anesthesia, we found increased fMRI signals in focal regions including the perioral somatosensory cortex, known to be intensely involved during seizures, whereas the occipital cortex was spared. For comparison, we also studied bicuculline-induced generalized tonic-clonic seizures under the same conditions, and found fMRI increases to be larger and more widespread than during spike-and-wave seizures. These findings suggest that even in regions with intense neuronal activity during epileptic seizures, oxygen delivery exceeds metabolic needs, enabling fMRI to be used for investigation of dynamic cortical and subcortical network involvement in this disorder.

scholarly journals Reduced evoked activity and cortical oscillations are correlated with anisometric amblyopia and impairment of visual acuity

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hanna Julku ◽  
Santeri Rouhinen ◽  
Henri J. Huttunen ◽  
Laura Lindberg ◽  
Johanna Liinamaa ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Neuronal Activity ◽  
Higher Order ◽  
Evoked Responses ◽  
Healthy Human ◽  
Visual Deficits ◽  
Electrophysiological Recordings ◽  
Visual Areas ◽  
Visual Tasks ◽  
Evoked Activity

AbstractAmblyopia is a developmental disorder associated with abnormal visual experience during early childhood commonly arising from strabismus and/or anisometropia and leading to dysfunctions in visual cortex and to various visual deficits. The different forms of neuronal activity that are attenuated in amblyopia have been only partially characterized. In electrophysiological recordings of healthy human brain, the presentation of visual stimuli is associated with event-related activity and oscillatory responses. It has remained poorly understood whether these forms of activity are reduced in amblyopia and whether possible dysfunctions would arise from lower- or higher-order visual areas. We recorded neuronal activity with magnetoencephalography (MEG) from anisometropic amblyopic patients and control participants during two visual tasks presented separately for each eye and estimated neuronal activity from source-reconstructed MEG data. We investigated whether event-related and oscillatory responses would be reduced for amblyopia and localized their cortical sources. Oscillation amplitudes and evoked responses were reduced for stimuli presented to the amblyopic eye in higher-order visual areas and in parietal and prefrontal cortices. Importantly, the reduction of oscillation amplitudes but not that of evoked responses was correlated with decreased visual acuity in amblyopia. These results show that attenuated oscillatory responses are correlated with visual deficits in anisometric amblyopia.

Altered somatosensory cortex neuronal activity in a rat model of Parkinson's disease and levodopa-induced dyskinesias

2017 ◽  
Vol 294 ◽  
pp. 19-31 ◽  
Author(s):  
Mesbah Alam ◽  
Regina Rumpel ◽  
Xingxing Jin ◽  
Christof von Wrangel ◽  
Sarah K. Tschirner ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Somatosensory Cortex ◽  
Neuronal Activity ◽  
Rat Model

scholarly journals Neuronal Responses to Short Wavelength Light Deficiency in the Rat Subcortical Visual System

2021 ◽  
Vol 14 ◽  
Author(s):  
Patrycja Orlowska-Feuer ◽  
Magdalena Kinga Smyk ◽  
Anna Alwani ◽  
Marian Henryk Lewandowski
Keyword(s):  
Neuronal Activity ◽  
Short Wavelength ◽  
Uv Light ◽  
Spectral Composition ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Neuronal Responses ◽  
Polychromatic Light ◽  
Electrophysiological Recordings ◽  
Pretectal Nucleus ◽  
Short Wavelength Light

The amount and spectral composition of light changes considerably during the day, with dawn and dusk being the most crucial moments when light is within the mesopic range and short wavelength enriched. It was recently shown that animals use both cues to adjust their internal circadian clock, thereby their behavior and physiology, with the solar cycle. The role of blue light in circadian processes and neuronal responses is well established, however, an unanswered question remains: how do changes in the spectral composition of light (short wavelengths blocking) influence neuronal activity? In this study we addressed this question by performing electrophysiological recordings in image (dorsal lateral geniculate nucleus; dLGN) and non-image (the olivary pretectal nucleus; OPN, the suprachiasmatic nucleus; SCN) visual structures to determine neuronal responses to spectrally varied light stimuli. We found that removing short-wavelength from the polychromatic light (cut off at 525 nm) attenuates the most transient ON and sustained cells in the dLGN and OPN, respectively. Moreover, we compared the ability of different types of sustained OPN neurons (either changing or not their response profile to filtered polychromatic light) to irradiance coding, and show that both groups achieve it with equal efficacy. On the other hand, even very dim monochromatic UV light (360 nm; log 9.95 photons/cm2/s) evokes neuronal responses in the dLGN and SCN. To our knowledge, this is the first electrophysiological experiment supporting previous behavioral findings showing visual and circadian functions disruptions under short wavelength blocking environment. The current results confirm that neuronal activity in response to polychromatic light in retinorecipient structures is affected by removing short wavelengths, however, with type and structure – specific action. Moreover, they show that rats are sensitive to even very dim UV light.

An integrated microfluidic/microelectrode array for the study of activity-dependent intracellular dynamics in neuronal networks

Lab on a Chip ◽  
2018 ◽  
Vol 18 (22) ◽  
pp. 3425-3435 ◽  
Author(s):  
Eve Moutaux ◽  
Benoit Charlot ◽  
Aurélie Genoux ◽  
Frédéric Saudou ◽  
Maxime Cazorla
Keyword(s):  
Neuronal Activity ◽  
Neuronal Networks ◽  
Microelectrode Array ◽  
Activity Dependent

A microfluidics/MEA platform was developed to control neuronal activity while imaging intracellular dynamics within reconstituted neuronal networks.

scholarly journals Oscillations in cortico-basal ganglia circuits: implications for Parkinson’s disease and other neurologic and psychiatric conditions

2019 ◽  
Vol 122 (1) ◽  
pp. 203-231 ◽  
Author(s):  
Pär Halje ◽  
Ivani Brys ◽  
Juan J. Mariman ◽  
Claudio da Cunha ◽  
Romulo Fuentes ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Neuronal Activity ◽  
Pathophysiological Mechanism ◽  
Electrophysiological Recordings ◽  
Wide Range ◽  
Psychiatric Conditions ◽  
Higher Cognitive Functions ◽  
And Control

Cortico-basal ganglia circuits are thought to play a crucial role in the selection and control of motor behaviors and have also been implicated in the processing of motivational content and in higher cognitive functions. During the last two decades, electrophysiological recordings in basal ganglia circuits have shown that several disease conditions are associated with specific changes in the temporal patterns of neuronal activity. In particular, synchronized oscillations have been a frequent finding suggesting that excessive synchronization of neuronal activity may be a pathophysiological mechanism involved in a wide range of neurologic and psychiatric conditions. We here review the experimental support for this hypothesis primarily in relation to Parkinson’s disease but also in relation to dystonia, essential tremor, epilepsy, and psychosis/schizophrenia.

scholarly journals Altered Recruitment of Motor Cortex Neuronal Activity During the Grasping Phase of Skilled Reaching in a Chronic Rat Model of Unilateral Parkinsonism

2019 ◽  
Vol 39 (48) ◽  
pp. 9660-9672 ◽  
Author(s):  
Brian I. Hyland ◽  
Sonja Seeger-Armbruster ◽  
Roseanna A. Smither ◽  
Louise C. Parr-Brownlie
Keyword(s):  
Motor Cortex ◽  
Neuronal Activity ◽  
Rat Model ◽  
Skilled Reaching
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