Dichotic Listening, Event-Related Potentials, and Interhemispheric Transfer in the Elderly

Abstract

Objective: To determine the basis for the large, age-related asymmetries in dichotic listening performance scores reported by Jerger et al. (1994).Design: Behavioral and electrophysiologic responses to dichotic listening tasks in both verbal and nonverbal paradigms were obtained in four groups of subjects: young adults with normal hearing, elderly persons with presbyacusis, elderly persons with presbyacusis and marked dichotic deficits, and patients with lesions of the corpus callosum.Results: In comparison with the young group the two elderly groups showed an increasing left-ear deficit on the verbal task, and an increasing rightear deficit on the nonverbal paradigm. The pattern of results obtained in the elderly persons with marked dichotic deficits was similar to the pattern of results in the group with callosal lesions. Conclusions: With age, there may be a significant loss of efficiency of interhemispheric transfer of auditory information through the corpus callosum. Such age-related deficit might have important implications for the effective use of binaural information by elderly persons. (Ear & Hearing 1995;16;482-498)Whenever a verbal task is presented in the dichotic mode, there is a slight performance advantage for the right ear input over the left ear input. For a recent summary of the extensive evidence for the right ear-advantage (REA) for verbal stimuli, see Hugdahl (1988) and Hellige (1993). A commonly accepted explanation for the REA derives from two principles: first, the left hemisphere is specialized for the processing of verbal materials; second, the right ear enjoys privileged access to the left hemisphere. In effect the right ear is directly connected to the left hemisphere via the crossed afferent auditory pathway, while the left ear, connected directly to the right hemisphere, has access to the left hemisphere only via the interhemispheric connecting pathways in the corpus callosum (Zaidel, 1983).The extent to which aging affects dichotic listening ability and the REA has been controversial.Early studies, utilizing primarily the Staggered Spondee Word (SSW) test, the masking-level difference (MLD) test, or Consonant-Vowel (CV) syllables were well summarized by Willott (1991). " . . . while age-related declines in binaural processing may occur, they are not especially pronounced in many cases'' (p. 234). "Although substantial age-related declines were frequently observed, the effects were attenuated when progression in degree of peripheral hearing loss was taken into account" (4, p. 232).More recently, however, newer dichotic paradigms have suggested more robust age effects. In a task involving the identification of dichotically presented sentences, for example, Jerger, Chmiel, Allen, and Wilson (1994) showed a substantial agerelated performance decline, in both free-report and directed-report modes, which could not be explained by degree of peripheral hearing sensitivity loss. Similar aging effects on dichotic listening have been noted by Barr and Giambra (1990), using a word shadowing tec...

Effect of auditory training on the middle latency response in children with (central) auditory processing disorder

“…This reduced left hemisphere input could be associated with the maturation of myelin in the corpus callosum and in related pathways. A lack of callosal input to the left hemisphere has been shown in secondary topographic mapping to possibly be the result of degeneration (demyelination) of the corpus callosum in relation to aging (37). In addition, one of the training procedures employed in this study was dichotic interaural intensity difference training.…”

Age Effects in Identifying and Localising Dichotic Stimuli: A Corpus Callosum Deficit

“…1A). Several studies also found an age-related decrease of LE performance (Alden et al, 1997;Bellis & Wilber, 2001;Bouma & Van der Endt, 1993;Hallgren et al, 2001;Jerger et al, 1994Jerger et al, , 1995Strouse et al, 2000aStrouse et al, , 2000b.…”

“…Indeed, research has demonstrated that the DLT performance of elderly is decreased compared to younger participants (Alden, Harrison, Snyder, & Everhart, 1997;Bouma & Van der Endt, 1993;Gelfand, Hoffman, Waltzman, & Piper, 1980;Hallgren, Larsby, Lyxell, & Arlinger, 2001;Martin & Cranford, 1991;Strouse, Wilson, & Brush, 2000a). Also, an age-related increase of ear asymmetry has been reported: performance of the LE has been found to decrease stronger than performance of the RE (Jerger, Alford, Lew, Rivera, & Chmiel, 1995;Jerger, Chmiel, Allen, & Wilson, 1994;Strouse et al, 2000a;Strouse, Wilson, & Brush, 2000b). However, this finding is still controversial since some aging studies have failed to find such an effect (Gelfand et al, 1980;Martini et al, 1988) or found that age effects could only be perceived in focussed attention conditions, in particular when attention had to be focussed at the LE (Alden et al, 1997;Bouma & Van der Endt, 1993;Hallgren et al, 2001).…”

Avaliação do processamento auditivo em idosos que relatam ouvir bem

“…The elderly have a worse performance in low redundancy hearing tasks, in dichotic hearing tasks and in temporal pattern tasks when compared to adult individuals and such findings could indicate impairment in central auditory pathways 1,[5][6][7][8][9][10][11] . Right ear advantage (REA) seen in dichotic listening tests, was considered as stemming from an impairment of the inter-hemispheric auditory pathways.…”

“…Right ear advantage (REA) seen in dichotic listening tests, was considered as stemming from an impairment of the inter-hemispheric auditory pathways. [8][9][10][11] Auditory processing assessment information is important to identify functional deficits that could be associated to difficulties in speech understanding 12 , in audiologic rehabilitation/training 13 and to check the results of treatment interventions 14 . Ipsilateral synthetic phrases identification test with competitive message (SSI/MCI), frequency patterns test (PPS) and the alternate dissyllable by dichotic task test (SSW) are behavioral sensitive tests, with specificity, reliability and facility to use in certain lesions or dysfunctions of the different areas of the auditory central nervous system (ACNS).…”