Journal of Neurophysiology

Chin, Alfred C.

doi: 10.1152/jn.00848.2018pmid: 30673358

The recent discovery of cyclic GMP-AMP synthase (cGAS) as the mammalian cytosolic DNA sensor has profound therapeutic implications for infection, immunology, and cancer. Because neurovirology, neuroimmunology, neuro-oncology, and neurodegeneration implicate cytosolic DNA sensing, cGAS activation and induction of the downstream signaling protein stimulator of interferon genes (STING) has become increasingly recognized as a crucial determinant of neuropathophysiology. This Neuro Forum article reviews recent advances on the role of cGAS-STING signaling in neuroinflammation and neurological disease.

Pan, Yu-Zhen; Sutula, Thomas P.; Rutecki, Paul A.

doi: 10.1152/jn.00723.2018pmid: 30673364

2-Deoxy-d-glucose (2DG) is a glycolytic inhibitor and suppresses epileptiform activity acutely and has chronic antiepileptic effects. The mechanisms of the acute effects are not well delineated. In this study, we show 2DG suppressed abnormal network epileptiform activity without effecting normal synaptic network activity or membrane properties. The effects appear to be use dependent and have a presynaptic locus of action. Inhibition of glycolysis is a novel presynaptic mechanism to limit abnormal neuronal network activity and seizures.

Kruszynski, Sandra; Stanaitis, Kornelijus; Brandes, Janine; Poets, Christian F.; Koch, Henner

doi: 10.1152/jn.00304.2018pmid: 30699003

The clinically used respiratory stimulant doxapram has distinct effects on the rhythm generating kernel (pre-Bötzinger complex) and motor output centers (Nucleus Hypoglossus). These effects are obliterated during hypoxia and are mediated by distinct changes in the intrinsic properties of neurons of the nucleus hypoglossus and synaptic transmission received by pre-Bötzinger complex neurons.

Versace, Viviana; Campostrini, Stefania; Sebastianelli, Luca; Saltuari, Leopold; Kofler, Markus

doi: 10.1152/jn.00554.2018pmid: 30811266

The present findings demonstrate for the first time that a spinally organized protective reflex, the cutaneous silent period (CSP), may be modulated by top-down corticospinal facilitatory input when the stimulated hand enters the defensive peripersonal space (DPPS) of the face. In particular, the cortically mediated excitatory long-loop reflex, which may interrupt the CSP, is facilitated when the stimulated hand is in the DPPS, irrespective of visual control over the hand. No spinal inhibitory CSP parameter differs significantly in or outside the DPPS.

Tikidji-Hamburyan, Ruben A.; Leonik, Conrad A.; Canavier, Carmen C.

doi: 10.1152/jn.00728.2018pmid: 30726155

We show that jitter induced by sparse connectivity can destabilize global synchrony but not a two-cluster state with two smaller clusters firing alternately. On the other hand, conduction delays stabilize synchrony and destroy two-cluster states. These results hold if each cluster exhibits a phase response curve similar to one that characterizes fast-spiking basket and cortical low-threshold-spiking cells for strong inhibition. Either a two-cluster or a one-cluster state might provide the oscillatory substrate for neural computations.

Smith, Lyndon J.; Macefield, Vaughan G.; Birznieks, Ingvars; Burton, Alexander R.

doi: 10.1152/jn.00862.2018pmid: 30699044

Data obtained in the cat have shown that muscle pain causes a marked increase in the firing of muscle spindles, attributed to a nociceptor-driven fusimotor reflex. However, our studies of muscle spindles in relaxed leg muscles failed to find any effect on spindle discharge. Here we showed that experimental muscle pain failed to increase the firing of muscle spindle afferents during weak voluntary contractions, when fusimotor drive sufficient to increase their firing is present.

Adams, Natalie E.; Teige, Catarina; Mollo, Giovanna; Karapanagiotidis, Theodoros; Cornelissen, Piers L.; Smallwood, Jonathan; Traub, Roger D.; Jefferies, Elizabeth; Whittington, Miles A.

doi: 10.1152/jn.00686.2018pmid: 30699059

Here, we show, for the first time, that a network of spatially distributed brain regions can be revealed by cross-frequency coupling between delta and theta frequencies in subjects using magnetoencephalography recording during a semantic decision task. A biological model of this cross-frequency coupling suggested an interlaminar, cell-specific division of labor within the neocortex may serve to route the flow of cortico-cortical and cortico-subcortical information to promote such spatially distributed, functional networks.

Davare, Marco; Parikh, Pranav J.; Santello, Marco

doi: 10.1152/jn.00800.2018pmid: 30726158

The relative contribution of predictive and feedback mechanisms for scaling digit forces to position during dexterous manipulation depends on the predictability of where the object will be grasped. We found that corticospinal excitability shortly after contact was sensitive to digit position predictability. This supports the proposition that distinct sensorimotor integration processes are engaged, depending on the role of feedback about digit placement versus sensorimotor memory in controlling manipulative forces.

Bautista, Tara G.; Leech, Jennifer; Mazzone, Stuart B.; Farrell, Michael J.

doi: 10.1152/jn.00547.2018pmid: 30649977

Functional brain imaging in humans was optimized for the brain stem. We provide the first detailed description of brain stem sites activated in response to airway irritation. The results are consistent with findings in animal studies and extend our foundational knowledge of brain processing of airway irritation in humans.

Carter, Jason R.

doi: 10.1152/jn.00570.2018pmid: 30673363

The technique of microneurography has advanced the field of neuroscience for the past 50 years. While there have been a number of reviews on microneurography, this paper takes an objective approach to exploring the impact of microneurography studies. Briefly, Web of Science (Thomson Reuters) was used to identify the highest citation articles over the past 50 years, and key findings are presented in a decade-by-decade highlight. This includes the establishment of microneurography in the 1960s, the acceleration of the technique by Gunnar Wallin in the 1970s, the international collaborations of the 1980s and 1990s, and finally the highest impact studies from 2000 to present. This journey through 50 years of microneurographic research related to peripheral sympathetic nerve activity includes a historical context for several of the laboratory interventions commonly used today (e.g., cold pressor test, mental stress, lower body negative pressure, isometric handgrip, etc.) and how these interventions and experimental approaches have advanced our knowledge of cardiovascular, cardiometabolic, and other human diseases and conditions.