Lack of bilateral generalization of adaptation to auditory rearrangement.

Abstract

Theoretical speculations concerning the presence or absence of intermanual transfer under differing conditions of sensorimotor adaptation have assumed that the adaptation produced by them are essentially equivalent. The possibility remains that sensorimotor changes generated by these different exposure conditions may be dissimilar. In order to resolve this, it is necessary to obtain relevant information from exposure conditions that provide adequate controls. Auditory rearrangement produced by functional rotation of the interaural axis by pseudophones (a binaural microphone/earphone array worn on the head), represents an exposure condition with suitable controls. Intermanual transfer of adaptation to rearranged ear-hand coordination produced after exposure to a 30° shift of the interaural axis was therefore investigated. FINDINGS Except for one exposure condition, changes in ear-hand coordination that occur to compensate the distortion induced by the pseudophones, fail to transfer intermanually. Such results suggest a differential representation of the sensorimotor function between the hemispheres. APPLICATION These findings are useful in design of auditory passive detection systems employing auditory tracking. They are for use of systems designers and human factors applications where sensorimotor tasks under conditions of perceptual rearrangement are anticipated. This information is of definite value to Naval medical officers in ear, nose, and throat specialities, and to audiologists.

Adapting to remapped auditory localization cues: A decision-theory model

“…In most such studies with vision, the perceptual effects of viewing the world through prisms that rotate the visual field are investigated. In the majority of such studies with audition, the question of how mean localization judgments change when the interaural axis is effectively rotated is investigated (see, e.g., Day & Singer, 1967;Kalil & Freedman, 1967;Mikaelian, 1969Mikaelian, , 1972Mikaelian, , 1974Recanzone, 1998;Willey, Inglis, & Pearce, 1937;Young, 1928). (For a review of auditory adaptation, see ShinnCunningham, Lehnert, Kramer, Wenzel, & Durlach, 1997; for a review of adaptation studies in general, see Welch, 1978.…”

Effects of Head Movements on Sound Localization With an Electronic Pseudophone

“…The results, obtained by Young (1928) and Willey et al (1937), that there were no auditory aftereffects when the reversing pseudophone was removed after their subjects had been exposed to the auditory rearrangement led the investigators to conclude that human subjects are incapable of reacquiring normal auditory localization of unseen sound sources when auditory space was pseudophonically reversed (Welch, 1978). Thus, later investigators have examined human adaptability to a " less drastic" auditory rearrangement (e. g., Freedman, Wilson, & Rekosh, 1967;Held, 1955;Mikaelian, 1972).…”

Prism adaptation in left-handers

“…Additivity One of the most firmly established facts of prism adaptation is the additivity of the component aftereffects (e.g., Hay & Pick, 1966;Hay, 1970;Hay & Brouchon, 1972;Mikaelian, 1970Mikaelian, , 1972Mikaelian, , 1974Redding, 1978;Redding & Wallace, 1976, 1990Templeton et al, 1974;Wallace & Garrett, 1975;Wallace & Redding, 1979;Wilkinson, 1971). That is, visual and proprioceptive aftereffects usually sum to the total aftereffect in the eye-hand coordination loop exercised during exposure.…”