The functional effectiveness of neck muscle reflexes for head-righting in response to sudden fall

Experimental Brain Research
Y ItoM Gresty

Abstract

Reflex head-righting in normal and labyrinthine-defective (LD) subjects was compared to identify the relative functional effectiveness of vestibular-collic and cervico-collic myotactic reflexes. To restrict stimuli largely to the head and neck, subjects lay supine, supported up to the shoulders on a horizontal bed with their head supported in a sling over the edge. The head fell freely as the sling was released with an electromagnetic catch. Head drops were delivered with the subjects instructed to relax and accept the fall passively or to actively right the head as fast as possible. With both instructions, righting responses in normal subjects commenced with electromyographic (EMG) bursts in the sternocleidomastoid (SCM) at 24.5 ms latency, which was reflected in a deceleration of the downwards head velocity. The latency of the earliest EMG responses in LD subjects was 67.4 ms, accompanied by similar deceleration. It is assumed that the earliest response in normal subjects is vestibular, whereas in LDs the SCM stretch reflex is the earliest response. These reflexes are followed at circa 100 ms by more intense EMG activity due to voluntary movement, but braking of head fall is evident before voluntary activity takes effect. Rig...Continue Reading

Citations

Mar 29, 2011·Experimental Brain Research·Jay M Goldberg, Kathleen E Cullen
Nov 22, 2002·Gait & Posture·Ajitkumar P MulavaraJacob J Bloomberg
Jun 4, 2005·Journal of Applied Physiology·Torrey M J LoucksChristy L Ludlow
Feb 18, 2015·Clinical Biomechanics·Neil J ArtzPatricia Dolan
Jun 24, 2008·Journal of Biomechanics·Martin SimoneauTimothy C Hain
Nov 28, 2006·Journal of Science and Medicine in Sport·Makoto MizumachiToshiaki Ueno
Jun 29, 2005·Gait & Posture·Kai BötzelThomas Brandt
May 8, 2008·Accident; Analysis and Prevention·Loriann M Hynes, James P Dickey
Jan 22, 2005·Clinical Neurophysiology : Official Journal of the International Federation of Clinical Neurophysiology·Thomas Brandt, Michael Strupp
Mar 13, 2003·Experimental Brain Research·Karin Jaggi-Schwarz, Bernhard J M Hess
Jan 25, 2014·Sports Health·Zachary D W DezmanHamish A Kerr
Feb 5, 2005·Medicine and Science in Sports and Exercise·Ryan T TierneyJoseph Torg
Apr 11, 2003·Journal of Neurophysiology·Emily A Keshner
Sep 23, 2018·Sports Medicine·Enora Le FlaoDoug King
Aug 22, 2000·Journal of Manipulative and Physiological Therapeutics·C G Davis

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.