Journal of Neurophysiology

Updating the role of force feedback in the spinal cord

What role does force feedback from Golgi tendon organs play in regulating mechanics during voluntary limb movement? Within the spinal cord, force feedback has excitatory and inhibitory components that co-exist in various combinations based on motor task and integrated with length feedback at the pre-motoneuronal and motoneuronal levels. In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Dr. Richard Nichols (Georgia Tech) about a new review article which explores recent research on distributed force feedback and motor control. Listen to learn about historical views, new results, and future work in this important area!

Distributed force feedback in the spinal cord and the regulation of limb mechanics
T. Richard Nichols
Journal of Neurophysiology, published online December 6, 2017. DOI: 10.1152/jn.00216.2017.

A new paradigm for training rhesus monkeys

Standardized training protocols are necessary in all animal research. However, new technology has allowed automation of training protocol, guaranteeing a greater degree of control and standardization than ever before. In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Dr. Michael Berger (German Primate Center), Dr. Antonino Calapai (German Primate Center), and Dr. Valeska Stephan (German Primate Center) about their new across-task unsupervised training (AUT) paradigm for rhesus monkeys in neuroscience research settings. Listen to learn about a recent study on the effectiveness, benefits, and challenges of using the AUT.

Standardized automated training of rhesus monkeys for neuroscience research in their housing environment
Michael Berger, Antonino Calapai, Valeska Stephan, Michael Niessing, Leonore Burchardt, Alexander Gail, and Stefan Treue
Journal of Neurophysiology, published online November 15, 2017. DOI: 10.1152/jn.00614.2017.

Breathing above the brain stem

What neural circuitry is engaged in the conscious control of breathing? While most neurophysiological research on breathing focuses on the automatic control in the brainstem, a recently-published study provides a novel look at the tracking of the breathing cycle in widespread cortical and limbic sites in humans. In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with authors Dr. Jose Herrero (Northwell Health; Feinstein Institute for Medical Research) and Dr. Ashesh Mehta (Northwell Health; Feinstein Institute for Medical Research) about their work. Listen to learn about the recording methods employed, the types of activity discovered, and the implications for volitional control and awareness of breathing.

Breathing above the brain stem: volitional control and attentional modulation in humans
Jose L. Herrero, Simon Khuvis, Erin Yeagle, Moran Cerf, and Ashesh D. Mehta
Journal of Neurophysiology, published online January 3, 2018. DOI: 10.1152/jn.00551.2017.

ADHD and tactile processing

There is much observational and anecdotal evidence for problems with tactile sensory processing in children with ADHD. However, there have previously been virtually no attempts to rigorously quantify differences in tactile sensitivity, habituation, and discrimination between ADHD and non-ADHD children. In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Dr. Nicolaas Puts (Johns Hopkins University School of Medicine; Kennedy Krieger Institute) and Dr. Stewart Mostofsky (Johns Hopkins University School of Medicine; Kennedy Krieger Institute) about a new study which employed recent innovations in neuroimaging to examine whether children with ADHD showed impaired performance on tactile tasks related to GABAergic inhibitory control. Listen to learn about links between ADHD and neural inhibition, the methods used to test tactile performance, and the specific findings of altered tactile processing in children with ADHD.

Altered tactile sensitivity in children with attention-deficit hyperactivity disorder
Nicolaas A. J. Puts, Ashley D. Harris, Mark Mikkelsen, Mark Tommerdahl, Richard A. E. Edden, and Stewart H. Mostofsky
Journal of Neurophysiology, published online November 30, 2017. DOI: 10.1152/jn.00087.2017.

Tests of the sorption and olfactory 'fovea' hypotheses in the mouse

What need could there be for either nearest-neighbor relationships or nonuniform distributions of receptor cells in the olfactory epithelium (OE)? In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Professor David Coppola (Randolph-Macon College, Ashland, Virginia) about a recent article which provides a novel test of the longstanding “sorption hypothesis” and related "fovea hypothesis", which posit that physical properties of odors, such as volatility and water solubility, determine a spatial pattern of stimulation across the OE that could aid odor discrimination. Listen to learn about the empirical and computational methods used to test these hypotheses, and the results which partially undermined the hypotheses!

Tests of the sorption and olfactory "fovea" hypotheses in the mouse
David M. Coppola, Brittaney E. Ritchie, and Brent A. Craven
Journal of Neurophysiology, published online November 7, 2017. DOI: 10.1152/jn.00455.2017.

Acetylcholine and the efferent vestibular system

The efferent vestibular system (EVS) has two effects on afferent activity: 1) increases background afferent discharge; and 2) decreases afferent sensitivity to rotational stimuli. What cellular mechanisms might contribute to these responses? In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Lauren Poppi (University of Newcastle, Australia) and Alan Brichta (University of Newcastle, Australia) about their recent article in which they expore the hypothesis that "the reduction in afferent sensitivity was attributed, in part, to the activation of alpha9-containing nAChRs ( 9nAChRs) and small-conductance potassium channels (SK) in vestibular type II hair cells." Listen to learn about their methods, the results, and more!

ACh-induced hyperpolarization and decreased resistance in mammalian type II vestibular hair cells
Lauren Ashlee Poppi, Hessam Tabatabaee, Hannah Rose Drury, Phillip Jobling, Robert J Callister, Americo A. Migliaccio, Paivi M Jordan, Joseph Christopher Holt, Richard D Rabbitt, Rebecca Lim, and Alan Martin Brichta
Journal of Neurophysiology, published online November 14, 2017. DOI: 10.1152/jn.00030.2017.

A case study on camptocormia

Can studying an individual patient with camptocormia reveal new information about the neural control of balance and posture? In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Rebecca St. George (University of Tasmania) and Fay Horak (Oregon Health and Science University) about the very first "Case Study in Neuroscience" article published in the Journal of Neurophysiology. The authors completed a wide variety of tests and found that "the disorder in this case was due to a disruption in the automatic, tonic drive to the postural muscles and myogenic changes were secondary," which demonstrates a divergence in the neural control of balance and posture.

Case Studies in Neuroscience: A Dissociation of Balance and Posture Demonstrated by Camptocormia
Rebecca J. St George, Victor S. Gurfinkel, Jeff Kraakevik, John G. Nutt, Fay B. Horak
Journal of Neurophysiology, published online October 4, 2017. DOI: 10.1152/jn.00582.2017.

Neural oscillations and phase-amplitude coupling in Parkinson's disease

Oscillatory neural activity in different frequency bands and phase-amplitude coupling (PAC) are hypothesized to be biomarkers of Parkinson’s disease (PD). Might these activity features help explain PD motor dysfunction, and serve as viable targets for closed-loop deep brain stimulation (DBS)? In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with David Escobar Sanabria (Department of Neurology, University of Minnesota) and Luke Johnson (Department of Neurology, University of Minnesota) about a recent study which explored these questions. Their findings helped to characterize these biomarkers across various vigilance states, and to build a foundation for future therapeutic techniques.

Parkinsonism and vigilance: alteration in neural oscillatory activity and phase-amplitude coupling in the basal ganglia and motor cortex
David Escobar Sanabria, Luke A. Johnson, Shane D. Nebeck, Jianyu Zhang, Matthew D. Johnson, Kenneth B. Baker, Gregory F. Molnar, Jerrold L. Vitek
Journal of Neurophysiology, published online November 3, 2017. DOI: 10.1152/jn.00388.2017.

A frequency-dependent dual role for Aβ afferents during dynamic mechanical allodynia

It is thought that myelinated primary afferent fibers switch modality from light touch to pain following injury, which is referred to as dynamic mechanical allodynia (DMA). However, do the firing rates of Aβ afferents affect the intensity of perceived pain during DMA? In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Line Loken (UCSF) about a recent study which explored this question. Surprisingly, following capsaicin-induced DMA there was an inverse relationship between Aβ firing rates and unpleasantness, such that brush stimuli that produced low firing rates were most painful and those that elicited high firing rates were rated as pleasant.

Low-threshold mechanoreceptors play a frequency-dependent, dual role in subjective ratings of mechanical allodynia
Line Sofie Loken, Eugene Duff, Irene Tracey
Journal of Neurophysiology, published online September 27, 2017. DOI: 10.1152/jn.00977.2016.

Early psychosocial neglect and developing brain networks

What effects do early psychosocial neglect and institutional rearing have on developing brain networks? In this podcast, Editor-in-Chief Bill Yates (University of Pittsburgh) talks with Caterina Stamoulis (Harvard Medical School and Boston Children's Hospital) about findings from the Bucharest Early Intervention Project (BEIP). Researchers demonstrated aberrantly connected task-independent brain networks in children that had been raised in Romanian institutions. These findings have profound implicaitons about the developmental and cognitive effects of early institutionalization.

Neuronal networks in the developing brain are adversely modulated by early psychosocial neglect
Catherine Stamoulis, Ross E. Vanderwert, Charles H. Zeanah, Nathan A. Fox, Charles A. Nelson
Journal of Neurophysiology, published online October 5, 2017. DOI: 10.1152/jn.00014.2017.