Middle-finger reflex.
A new reflex is described: middle-finger extensor reflex elicited by percussion of tendon insertion of musculus extensor digitorum communis in forearm. Following percussion using a reflex hammer, two EMG responses from the belly of the muscle were recorded: a short latency monosynaptic reflex with a latency of 31.4 +/- 1.5 ms (M1), and a long-latency middle-finger reflex with a mean latency of 64.8 +/- 6.31 ms (M2), the former being a monosynaptic extensor reflex, and the latter belonging to a spino-cortico-spinal reflex circuitry. It was suggested that the middle-finger extensor reflex elicited by radial nerve afferents and efferents (C7-C8) would be of clinical and theoretical importance.
Tan
Uner
U
Department of Physiology, Cukurova University Medical School, Adana, Turkey. unertan@cu.edu.tr
D000344:Afferent Pathways / Q000502:physiology; D004576:Electromyography / Q000379:methods; D005385:Fingers / Q000294:innervation* / Q000502:physiology*; D006801:Humans; D009119:Muscle Contraction / Q000502:physiology; D009431:Neural Conduction / Q000502:physiology; D010812:Physical Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D012018:Reflex / Q000502:physiology*