recruitment

1. In the testing of hearing, the abnormally greater increase in loudness in response to increments in intensity of the acoustic stimulus in an ear with a sensory hearing loss compared with a normal ear. 2. In neurophysiology, the activation of additional neurons (spatial r.) or an increase in their firing rate (temporal r.). SYN: recruiting response. SEE ALSO: irradiation. 3. The adding of parallel channels of flow in any system. [Fr. recrutement, fr. L. re-cresco, pp. -cretus, to grow again]

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re·cruit·ment ri-'krüt-mənt n

1) the increase in intensity of a reflex when the initiating stimulus is prolonged without alteration of intensity due to the activation of increasing numbers of motor neurons compare REINFORCEMENT

2) an abnormally rapid increase in the sensation of loudness with increasing sound intensity that occurs in deafness of neural origin and esp. in neural deafness of the aged in which soft sounds may be completely inaudible while louder sounds are distressingly loud

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n.

1. (in physiology) the phenomenon whereby an increase in the strength of a stimulus or repetition of the stimulus will stimulate increasing numbers of nerve cells to respond.

2. (in audiology) the phenomenon in which a person with sensorineural deafness cannot hear quiet sounds but can perceive loud sounds just as loudly as, or even more loudly than, a person with normal hearing.

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re·cruit·ment (re-krtґmənt) 1. the gradual increase to a maximum in a reflex when a stimulus of unaltered intensity is prolonged. 2. in audiology, an abnormally large increase in the perceived loudness of a sound caused by a slight increase in its intensity. 3. in muscle physiology, the orderly increase in number of activated motor units with increasing strength of voluntary muscle contractions. See also recruitment pattern.