Christopher I. Moore

John Brown University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

H. R. Burris

United States Naval Research Laboratory

William S. Rabinovich

United States Naval Research Laboratory

Rita Mahon

University of Maryland, College Park

P. Sprangle

University of Maryland, College Park

A. Ting

University of Maryland, College Park

Michele R. Suite

United States Naval Research Laboratory

Mike S. Ferraro

United States Naval Research Laboratory

James L. Murphy

Swansea Bay University Health Board

Stephanie R. Jones

John Brown University

G. C. Gilbreath

United States Naval Research Laboratory

Cooperative Institutions

Harvard University

114

United States Naval Research Laboratory

108

Brown University

Massachusetts Institute of Technology

Massachusetts General Hospital

K Lab (United States)

Allen Institute for Brain Science

Athinoula A. Martinos Center for Biomedical Imaging

John Brown University

Boston University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Optical Survey of the Tumble Rates of Retired GEO Satellites

Advanced Maui Optical and Space Surveillance Technologies Conference (2014)

Christopher R. Binz Mark A. Davis Bernie E. Kelm Christopher I. Moore

Abstract : The Naval Research Lab (NRL) and the Defense Advanced Research Projects Agency (DARPA) have made significant progress toward robotic rendezvous and docking between spacecraft, however the long-term attitude motion evolution of uncontrolled resident space objects has never been well-characterized. This effort set out to identify the motion exhibited in retired satellites at or near geosynchronous orbit (GEO). Through analysis of the periodic structure of observed reflected light curves, estimated tumble rates were determined for several retired satellites, typically in a super-GEO disposal orbit. The NRL's 1-meter telescope at Mid- way Research Center was used to track and observe the objects while the sun-satellite-observer geometry was most favorable; typically over a one- to two-hour period, repeated multiple times over the course of weeks. By processing each image with calibration exposures, the relative apparent magnitude of the brightness of the object over time was determined. Several tools, including software developed internally, were used for frequency analysis of the brightness curves. Results show that observed satellites generally exhibit a tumble rate well below the notional bounding case of one degree per second. When harmonics are found to exist in the data, modeling and simulation of the optical characteristics of the satellite can help to resolve ambiguities. This process was validated on spacecraft for which an attitude history is known, and agreement was found.

Rendezvous

Observer (physics)

Orbit Determination

Source

Cite

Citations (15)

Ca ²⁺ /calmodulin-dependent protein kinase II phosphorylation of the presynaptic protein synapsin I is persistently increased during long-term potentiation

Proceedings of the National Academy of Sciences (1996)

A. Nayak Christopher I. Moore Michael Browning

Long-term potentiation (LTP) is an increase in synaptic responsiveness thought to be involved in mammalian learning and memory. The localization (presynaptic and/or postsynaptic) of changes underlying LTP has been difficult to resolve with current electrophysiological techniques. Using a biochemical approach, we have addressed this issue and attempted to identify specific molecular mechanisms that may underlie LTP. We utilized a novel multiple-electrode stimulator to produce LTP in a substantial portion of the synapses in a hippocampal CA1 minislice and tested the effects of such stimulation on the presynaptic protein synapsin I. LTP-inducing stimulation produced a long-lasting 6-fold increase in the phosphorylation of synapsin I at its Ca 2+ /calmodulin-dependent protein kinase II (CaM kinase II) sites without affecting synapsin I levels. This effect was fully blocked by either the N -methyl- d -aspartate receptor antagonist d (−)-2-amino-5-phosphonopentanoic acid (APV) or the CaM kinase II inhibitor KN-62. Our results indicate that LTP expression is accompanied by persistent changes in presynaptic phosphorylation, and specifically that presynaptic CaM kinase II activity and synapsin I phosphorylation may be involved in LTP expression.

Synapsin I

Synapsin

LTP induction

10.1073/pnas.93.26.15451

Cite

Citations (91)

Persistent Gamma Spiking in Non-Sensory Fast-Spiking Cells Predicts Perceptual Success

SSRN Electronic Journal (2018)

Hyeyoung Shin Christopher I. Moore

Persistent gamma oscillations (30-55Hz) are hypothesized to temporally coordinate stimulus encoding, enabling perception. This prediction poses a conundrum: How can gamma serve as a template when the stimulus itself drives its mediators, presumably perturbing its maintenance? Specifically, fast-spiking interneurons (FS), a key gamma generator, can be highly sensory responsive. Further, the gamma-band local field potential (LFP) shows properties inconsistent with temporal coordination. Combining tetrode recording with controlled psychophysics revealed an FS subtype (γnsFS) that was not sensory responsive, whose inter-spike intervals peaked at gamma, and that fired with higher periodicity than other FS. Successful detection was predicted by increased regularity in γnsFS spiking at gamma, persisting from before to after sensory onset. In contrast, gamma LFP power negatively predicted detection, and was negatively related to gamma band spiking by γnsFS. These results suggest that a distinct interneuron subgroup, not ‘distracted’ by sensory input, mediates perceptually-relevant oscillations independent of LFP.

10.2139/ssrn.3227094

Cite

Citations (0)

A three-dimensional neural spheroid model for capillary-like network formation

Journal of Neuroscience Methods (2017)

Molly E. Boutin Liana Kramer Liane L. Livi Tyler Brown Christopher I. Moore

Spheroid

Vasculogenesis

10.1016/j.jneumeth.2017.01.014

Cite

Citations (47)

Thalamocortical mechanisms regulating the relationship between transient beta events and human tactile perception

bioRxiv (Cold Spring Harbor Laboratory) (2021)

Robert Law Sarah Pugliese Hyeyoung Shin Danielle D. Sliva Shane Lee

Abstract Transient neocortical events with high spectral power in the 15–29Hz beta band are among the most reliable predictors of sensory perception. Prestimulus beta event rates in primary somatosensory cortex correlate with sensory suppression, most effectively 100–300ms before stimulus onset. However, the neural mechanisms underlying this perceptual association are unknown. We combined human magnetoencephalography (MEG) measurements with biophysical neural modeling to test potential cellular and circuit mechanisms that underlie observed correlations between prestimulus beta events and tactile detection. Extending prior studies, we found that simulated bursts from higher-order, non-lemniscal thalamus were sufficient to drive beta event generation and to recruit slow supragranular inhibition acting on a 300ms time scale to suppress sensory information. Further analysis showed that the same beta generating mechanism can lead to facilitated perception for a brief period when beta events occur simultaneously with tactile stimulation before inhibition is recruited. These findings were supported by close agreement between model-derived predictions and empirical MEG data. The post-event suppressive mechanism explains an array of studies that associate beta with decreased processing, while the during-event faciliatory mechanism may demand a reinterpretation of the role of beta events in the context of coincident timing.

Magnetoencephalography

Stimulus (psychology)

BETA (programming language)

Sensory stimulation therapy

10.1101/2021.04.16.440210

Cite

Citations (8)

Tracking Calcium Dynamics and Immune Surveillance at the Choroid Plexus Blood-Cerebrospinal Fluid Interface

Neuron (2020)

Frederick B. Shipley Neil Dani Huixin Xu Christopher A Deister Jin Cui

Calcium imaging

10.1016/j.neuron.2020.08.024

Cite

Citations (82)

Neural Correlates of Tactile Detection: A Combined Magnetoencephalography and Biophysically Based Computational Modeling Study

Journal of Neuroscience (2007)

Stephanie R. Jones Dominique L. Pritchett Steven M. Stufflebeam Matti Hämäläinen Christopher I. Moore

Previous reports conflict as to the role of primary somatosensory neocortex (SI) in tactile detection. We addressed this question in normal human subjects using whole-head magnetoencephalography (MEG) recording. We found that the evoked signal (0-175 ms) showed a prominent equivalent current dipole that localized to the anterior bank of the postcentral gyrus, area 3b of SI. The magnitude and timing of peaks in the SI waveform were stimulus amplitude dependent and predicted perception beginning at approximately 70 ms after stimulus. To make a direct and principled connection between the SI waveform and underlying neural dynamics, we developed a biophysically realistic computational SI model that contained excitatory and inhibitory neurons in supragranular and infragranular layers. The SI evoked response was successfully reproduced from the intracellular currents in pyramidal neurons driven by a sequence of lamina-specific excitatory input, consisting of output from the granular layer (approximately 25 ms), exogenous input to the supragranular layers (approximately 70 ms), and a second wave of granular output (approximately 135 ms). The model also predicted that SI correlates of perception reflect stronger and shorter-latency supragranular and late granular drive during perceived trials. These findings strongly support the view that signatures of tactile detection are present in human SI and are mediated by local neural dynamics induced by lamina-specific synaptic drive. Furthermore, our model provides a biophysically realistic solution to the MEG signal and can predict the electrophysiological correlates of human perception.

Magnetoencephalography

10.1523/jneurosci.0482-07.2007

Cite

Citations (161)

Autism Overflows with Syntheses

Neuropsychology Review (2009)

Matthew K. Belmonte Yoram Bonneh Yael Adini Portia Iversen Natacha Akshoomoff

10.1007/s11065-009-9099-9

Cite

Citations (3)

Targeted optogenetic stimulation and recording of neurons in vivo using cell-type-specific expression of Channelrhodopsin-2

PMC (2010)