Dichotic words listening test: technical aspects and results in normal right-handed individuals

Caner-Cukiert, Ana Regina; Cukiert, Arthur

doi:10.1590/S0004-282X1994000200009

Abstracts

Dichotic listening tests have been being used in an increasing frequency to determine in a non-invasive way the cerebral dominance in right- and left-handed patients. This is especially relevant when surgery in eloquent brain areas is being contemplated. A Portuguese version of the dichotic words listening test was developed based mainly on Wexler's protocol. It consisted of 15 pairs of words with a stimulus dominance lower than 50%. They were recorded using natural voice and time and intensity synchronization by means of a specialized software. Each pair of words was presented twice in different channels within each block. The items were randomized and presented with a 300 msec interval between each trial. Four blocks of 30 pairs of words each were created, totalizing 120 trials. In the scoring process, the words heard over the right and left ears were wrote down. The number of times each word was heard over each ear was computed and their values subtracted yielding a partial score for each specific word pair. This process was repeated for all stimuli pair and a final score for right and left predominance was then reached. Thirty-two right handed normal individuals underwent the test 93.8% showed a right ear advantage. These results are very similar to the actual left hemisphere dominance rate in a right-handed population.

epilepsy; sodium amytal; dichotic listening tests; cerebral dominance

Testes de audição dicótica vêm sendo cada vez mais empregados na determinação da dominância hemisférica para linguagem sem a utilização de métodos invasivos em pacientes destros e canhotos. Isto é especialmente importante quando cirurgias em áreas eloquentes do cérebro estão sendo planejadas. Uma versão em português deste teste foi criada baseada principalmente no protocolo de Wexler. Ele consistiu de 15 pares de palavras com uma dominância de estímulo menor que 50%. Estas palavras foram gravadas com voz natural e com sincronização de inicio de apresentação e intensidade por meio da utilização de programa de computador especializado. Cada par de palavras era apresentado duas vezes em diferentes canais em cada bloco. Os itens foram randomizados e apresentados com um intervalo de 300 msec entre cada amostragem. Quatro blocos de 30 pares cada foram criados, totalizando 120 amostragens. Na quantificação do teste, as palavras ouvidas nos ouvidos esquerdo e direito eram computadas. Em cada par, os valores obtidos à esquerda e à direita eram subtraídos, dando origem a um resultado parcial para cada par de estímulos. Este processo era repetido para todos os estímulos e um resultado final de predominância esquerda/direita era alcançado. Trinta e dois indivíduos normais foram submetidos a este teste. Trinta deles mostraram superioridade de ouvido direito. Estes achados são bastante próximos do valor real da dominância hemisférica esquerda em uma população destra.

epilepsia; amital sódico; teste de audição dicótica; dominância cerebral

Dichotic words listening test: technical aspects and results in normal right-handed individuals

Teste de audição de palavras dicóticas: aspectos técnicos e resultados em pessoas destras normais

Ana Regina Caner-Cukiert; Arthur Cukiert

Deparment of Neurology and Neurosurgery, University of São Paulo School of Medicine, São Paulo, Brazil

SUMMARY

Dichotic listening tests have been being used in an increasing frequency to determine in a non-invasive way the cerebral dominance in right- and left-handed patients. This is especially relevant when surgery in eloquent brain areas is being contemplated. A Portuguese version of the dichotic words listening test was developed based mainly on Wexler's protocol. It consisted of 15 pairs of words with a stimulus dominance lower than 50%. They were recorded using natural voice and time and intensity synchronization by means of a specialized software. Each pair of words was presented twice in different channels within each block. The items were randomized and presented with a 300 msec interval between each trial. Four blocks of 30 pairs of words each were created, totalizing 120 trials. In the scoring process, the words heard over the right and left ears were wrote down. The number of times each word was heard over each ear was computed and their values subtracted yielding a partial score for each specific word pair. This process was repeated for all stimuli pair and a final score for right and left predominance was then reached. Thirty-two right handed normal individuals underwent the test 93.8% showed a right ear advantage. These results are very similar to the actual left hemisphere dominance rate in a right-handed population.

Key words: epilepsy, sodium amytal, dichotic listening tests, cerebral dominance.

RESUMO

Testes de audição dicótica vêm sendo cada vez mais empregados na determinação da dominância hemisférica para linguagem sem a utilização de métodos invasivos em pacientes destros e canhotos. Isto é especialmente importante quando cirurgias em áreas eloquentes do cérebro estão sendo planejadas. Uma versão em português deste teste foi criada baseada principalmente no protocolo de Wexler. Ele consistiu de 15 pares de palavras com uma dominância de estímulo menor que 50%. Estas palavras foram gravadas com voz natural e com sincronização de inicio de apresentação e intensidade por meio da utilização de programa de computador especializado. Cada par de palavras era apresentado duas vezes em diferentes canais em cada bloco. Os itens foram randomizados e apresentados com um intervalo de 300 msec entre cada amostragem. Quatro blocos de 30 pares cada foram criados, totalizando 120 amostragens. Na quantificação do teste, as palavras ouvidas nos ouvidos esquerdo e direito eram computadas. Em cada par, os valores obtidos à esquerda e à direita eram subtraídos, dando origem a um resultado parcial para cada par de estímulos. Este processo era repetido para todos os estímulos e um resultado final de predominância esquerda/direita era alcançado. Trinta e dois indivíduos normais foram submetidos a este teste. Trinta deles mostraram superioridade de ouvido direito. Estes achados são bastante próximos do valor real da dominância hemisférica esquerda em uma população destra.

Palavras-chave: epilepsia, amital sódico, teste de audição dicótica, dominância cerebral.

Texto completo disponível apenas em PDF.

Full text available only in PDF format.

Acknowledgments - We would like to thank Dr. Zatorre (Montreal Neurologic Institute) for allowing the use of all his Lab facilities and specialized software that made it possible to prepare this Portuguese version of the dichotic listening test.

Aceite: 5-outubro-1993.

Dr. Arthur Cukiert - Rua Baltazar da Veiga 367 apto 151 - 04510-001 São Paulo SP - Brasil.

1. Blumenstein S, Goodglass H, Tartter V. The reliability of ear advantage in dichotic listening. Brain & Language 1975, 2: 226-236.
2. Broadbent DE. Sucessive responses to simultaneous stimuli. Q J Exp Psychol 1956, 8: 145-162.
3. Bruder GE. Dichotic listening: new developments and applications in clinical research. Ann NY Acad Sci 1991, 620: 217-232.
4. Geffen G, Caudrey D. Reliability and validity of the dichotic monitoring test for language laterality. Neuropsychologia 1981, 19: 413-423.
5. Kimura D. Some effects of temporal lobe damage on auditory perception. Canad J Psychol 1961, 15: 156-165.
6. Kimura D. Cerebral dominance and the perception of verbal stimuli. Canad J Psychol 1961, 15: 166-171.
7. Rasmussen T, Milner B. The role of early left-brain injury in determining lateralization of cerebral speech functions. Ann NY Acad Sci 1977, 299: 355-364.
8. Repp BH. Identification of dichotic fusions. J Accoust Soc Am 1976, 60: 456-469.
9. Repp BH. Measuring laterality effects in dichotic listening. J Accoust Soc Am 1977, 62: 720-737.
10. Speaks C, Niccum N, Carney E. Statistical proprieties of responses to dichotic listening with CV nonsense syllables. Accoust Soc Am 1982, 72: 1185-1194.
11. Teng EL. Dichotic ear difference is a poor index for the functional asymmetry between the cerebral hemispheres. Neuropsychologia 1980, 19: 235-240.
12. Wada J, Rasmussen T. Intracarotid injection of sodium amytal for the lateralization of speech dominance: experimental and clinical observations. J Neurosurg 1960, 17: 266-282.
13. WexlerB, HalwesT, Heninger GR. Use of statistical significance criterion in drawing inferences about hemispheric dominance for language function from dichotic listening data. Brain & Language 1981, 13: 13-18.
14. Wexler BE, Halwes T. Increasing the power of dichotic methods: the fused rhimed words test. Neuropsychologia 1983, 21:59-66.
15. Zatorre RJ. Perceptual asymmetry on the dichotic fused words test and cerebral speech lateralization determined by the carotid sodium amytal test. Neuropsychologia 1989, 27: 1207-1209.

Publication Dates

Publication in this collection
19 Jan 2011
Date of issue
June 1994

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

[1] 1. Blumenstein S, Goodglass H, Tartter V. The reliability of ear advantage in dichotic listening. Brain & Language 1975, 2: 226-236.

[2] 2. Broadbent DE. Sucessive responses to simultaneous stimuli. Q J Exp Psychol 1956, 8: 145-162.

[3] 3. Bruder GE. Dichotic listening: new developments and applications in clinical research. Ann NY Acad Sci 1991, 620: 217-232.

[4] 4. Geffen G, Caudrey D. Reliability and validity of the dichotic monitoring test for language laterality. Neuropsychologia 1981, 19: 413-423.

[5] 5. Kimura D. Some effects of temporal lobe damage on auditory perception. Canad J Psychol 1961, 15: 156-165.

[6] 6. Kimura D. Cerebral dominance and the perception of verbal stimuli. Canad J Psychol 1961, 15: 166-171.

[7] 7. Rasmussen T, Milner B. The role of early left-brain injury in determining lateralization of cerebral speech functions. Ann NY Acad Sci 1977, 299: 355-364.

[8] 8. Repp BH. Identification of dichotic fusions. J Accoust Soc Am 1976, 60: 456-469.

[9] 9. Repp BH. Measuring laterality effects in dichotic listening. J Accoust Soc Am 1977, 62: 720-737.

[10] 10. Speaks C, Niccum N, Carney E. Statistical proprieties of responses to dichotic listening with CV nonsense syllables. Accoust Soc Am 1982, 72: 1185-1194.

[11] 11. Teng EL. Dichotic ear difference is a poor index for the functional asymmetry between the cerebral hemispheres. Neuropsychologia 1980, 19: 235-240.

[12] 12. Wada J, Rasmussen T. Intracarotid injection of sodium amytal for the lateralization of speech dominance: experimental and clinical observations. J Neurosurg 1960, 17: 266-282.

[13] 13. WexlerB, HalwesT, Heninger GR. Use of statistical significance criterion in drawing inferences about hemispheric dominance for language function from dichotic listening data. Brain & Language 1981, 13: 13-18.

[14] 14. Wexler BE, Halwes T. Increasing the power of dichotic methods: the fused rhimed words test. Neuropsychologia 1983, 21:59-66.

[15] 15. Zatorre RJ. Perceptual asymmetry on the dichotic fused words test and cerebral speech lateralization determined by the carotid sodium amytal test. Neuropsychologia 1989, 27: 1207-1209.