Biomaterial Database

Long latency reflex force of human finger muscles in response to imposed sinusoidal movements. 1984

J Noth, and H R Matthews, and H H Friedemann

Reflex stiffness of the flexing human index finger was studied using sinusoidal movements at 3-16 Hz. The Nyquist stiffness diagram indicates the presence of a 'presonance' at around 4 Hz, its 'C' shape after correction for the mechanical properties of the relaxed finger is consistent with the involvement of a stretch reflex in its generation. This contention was supported by the presence of negative friction around 4 Hz and the disappearance of the modulation of the stiffness curve after afferent ischaemic block. Correction for the mechanical properties of active muscle, measured after afferent block, permitted the isolation of the reflex component of stiffness. The circular form of the Nyquist diagram indicates a relatively flat frequency response for the reflex over the range tested, and its radius gives a measure of reflex gain. The low value of the frequency at which the frictional force is minimal, suggests the involvement of a reflex of longer than spinal latency. This is discussed in relation to mechanisms of tremor genesis and the interaction of spinal and long latency reflexes in distal hand muscles.

UI	MeSH Term	Description	Entries
D009046	Motor Neurons	Neurons which activate MUSCLE CELLS.	Neurons, Motor,Alpha Motorneurons,Motoneurons,Motor Neurons, Alpha,Neurons, Alpha Motor,Alpha Motor Neuron,Alpha Motor Neurons,Alpha Motorneuron,Motoneuron,Motor Neuron,Motor Neuron, Alpha,Motorneuron, Alpha,Motorneurons, Alpha,Neuron, Alpha Motor,Neuron, Motor
D009068	Movement	The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.	Movements
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D009424	Nervous System Physiological Phenomena	Characteristic properties and processes of the NERVOUS SYSTEM as a whole or with reference to the peripheral or the CENTRAL NERVOUS SYSTEM.	Nervous System Physiologic Processes,Nervous System Physiological Processes,Nervous System Physiology,Nervous System Physiological Concepts,Nervous System Physiological Phenomenon,Nervous System Physiological Process,Physiology, Nervous System,System Physiology, Nervous
D009475	Neurons, Afferent	Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.	Afferent Neurons,Afferent Neuron,Neuron, Afferent
D011930	Reaction Time	The time from the onset of a stimulus until a response is observed.	Response Latency,Response Speed,Response Time,Latency, Response,Reaction Times,Response Latencies,Response Times,Speed, Response,Speeds, Response
D012026	Reflex, Stretch	Reflex contraction of a muscle in response to stretching, which stimulates muscle proprioceptors.	Reflex, Tendon,Stretch Reflex,Tendon Reflex
D005385	Fingers	Four or five slender jointed digits in humans and primates, attached to each HAND.	Finger
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001696	Biomechanical Phenomena	The properties, processes, and behavior of biological systems under the action of mechanical forces.	Biomechanics,Kinematics,Biomechanic Phenomena,Mechanobiological Phenomena,Biomechanic,Biomechanic Phenomenas,Phenomena, Biomechanic,Phenomena, Biomechanical,Phenomena, Mechanobiological,Phenomenas, Biomechanic