Biomaterial Database

Monosynaptic reflexes in falling man. 1977

R Greenwood, and A Hopkins

We have examined peripheral proprioceptive input during fall in man. The first 80 ms of unexpected free fall, both in a parachute harness and while seated, has been studied using the monosynaptic Hoffman (H) and Achilles tendon (T) reflexes. Facilitation of the H reflex begins about 30 to 40 ms after release, representing the onset of motor neurone facilitation before the electromyographic activity which begins about 80 ms after release. Earlier facilitation of the T reflex may represent spindle excitation due to change in muscle shape as suggested by Matthews and Whiteside (1960), but the T reflex inhibition described by these authors after 50 ms of seated fall is probably a purely mechanical phenomenon.

UI	MeSH Term	Description	Entries
D009038	Motion	Physical motion, i.e., a change in position of a body or subject as a result of an external force. It is distinguished from MOVEMENT, a process resulting from biological activity.	Motions
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D011187	Posture	The position or physical attitude of the body.	Postures
D011434	Proprioception	Sensory functions that transduce stimuli received by proprioceptive receptors in joints, tendons, muscles, and the INNER EAR into neural impulses to be transmitted to the CENTRAL NERVOUS SYSTEM. Proprioception provides sense of stationary positions and movements of one's body parts, and is important in maintaining KINESTHESIA and POSTURAL BALANCE.	Labyrinthine Sense,Position Sense,Posture Sense,Sense of Equilibrium,Vestibular Sense,Sense of Position,Equilibrium Sense,Sense, Labyrinthine,Sense, Position,Sense, Posture,Sense, Vestibular
D012023	Reflex, Monosynaptic	A reflex in which the AFFERENT NEURONS synapse directly on the EFFERENT NEURONS, without any INTERCALATED NEURONS. (Lockard, Desk Reference for Neuroscience, 2nd ed.)	Monosynaptic Reflex
D012026	Reflex, Stretch	Reflex contraction of a muscle in response to stretching, which stimulates muscle proprioceptors.	Reflex, Tendon,Stretch Reflex,Tendon Reflex
D006181	H-Reflex	A monosynaptic reflex elicited by stimulating a nerve, particularly the tibial nerve, with an electric shock.	H Reflex,H-Reflexes,H Reflexes,Reflex, H
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000125	Achilles Tendon	Tendon that connects the muscles in the back of the calf to the HEEL BONE.	Calcaneal Tendon,Tendo Calcaneus,Calcaneal Tendons,Tendon, Achilles,Tendon, Calcaneal,Tendons, Calcaneal
D000843	Ankle Joint	The joint that is formed by the inferior articular and malleolar articular surfaces of the TIBIA; the malleolar articular surface of the FIBULA; and the medial malleolar, lateral malleolar, and superior surfaces of the TALUS.	Ankle Syndesmosis,Articulatio talocruralis,Distal Tibiofibular Joint,Inferior Tibiofibular Joint,Talocrural Joint,Tibiofibular Ankle Syndesmosis,Tibiofibular Syndesmosis,Ankle Joints,Ankle Syndesmoses,Ankle Syndesmosis, Tibiofibular,Distal Tibiofibular Joints,Inferior Tibiofibular Joints,Joint, Ankle,Joints, Ankle,Syndesmosis, Ankle,Talocrural Joints,Tibiofibular Ankle Syndesmoses,Tibiofibular Joint, Distal,Tibiofibular Syndesmoses