[Advances in the study of primary auditory cortex. Demostration of its activation by functional magnetic resonance imaging]. / Vanguardia en el estudio del córtex auditivo. Demostración de su activación mediante resonancia magnética funcional.

PURPOSE: The purpose of this preliminary study has been to demonstrate and investigate the activation patterns of the primary auditory cortex (Heschl's gyrus = HG) using functional magnetic resonance imaging (fMRI). MATERIAL AND METHODS: A 2500 Hz tone stimulus was delivered monoaurally to the right and left ear of 15 normal-hearing right-handed volunteers in 20-second on-off cycles. FMRI data were obtained using a 1.5-Tesla scanner and processed with SPM2. RESULTS: Activated pixels were identified in the transverse temporal gyrus (Heschl's gyrus) of both hemispheres in response to pure tone stimuli using cross-correlation analysis (P < 0.001). Bilateral hemispheric activation was observed in all subjects and there was a trend towards contralateral HG activation to the stimulated ear. CONCLUSION: These results demonstrate directly that fMRI is a new and useful imaging technique to study the complex auditory cortex and it will have potential clinical applications in the next future.

Vanguardia en el estudio del córtex auditivo. Demostración de su activación mediante resonancia magnética funcional / Advances in the study of primary auditory cortex. Demostration of its activation by functional magnetic resonance imaging

Objetivo: El objetivo de este estudio preliminar es investigar y demostrar la activación del córtex auditivo primario (Gyrus o circunvolución de Heschl) mediante resonancia magnética funcional (RMf). Material y métodos: Los sujetos a estudio fueron 15 voluntarios normooyentes diestros, a los que se les estimuló auditivamente con tonos de 2500 Hz en ciclos de 20 sg de estimulación, seguidos por 20 sg de reposo. Los datos fueron obtenidos en un escáner de RM de 1.5 Tesla y procesados con SPM2. Resultados: La activación en respuesta a la estimulación tonal, se produjo en todos los sujetos a nivel del Gyrus de Heschl (córtex auditivo primario) en ambos hemisferios cerebrales, con una significación estadística de P<0,001, y una tendencia a una mayor activación en el hemisferio contralateral al oído estimulado. Conclusión: Estos resultados demuestran que la RMf es un útil y novedoso intrumento para el estudio del complejo córtex auditivo, con importantes aplicaciones clínicas en un futuro próximo (AU)

PURPOSE: The purpose of this preliminary study has been to demonstrate and investigate the activation patterns of the primary auditory cortex (Heschl's gyrus = HG) using functional magnetic resonance imaging (fMRI). MATERIAL AND METHODS: A 2500 Hz tone stimulus was delivered monoaurally to the right and left ear of 15 normal-hearing right-handed volunteers in 20-second on-off cycles. FMRI data were obtained using a 1.5-Tesla scanner and processed with SPM2. RESULTS: Activated pixels were identified in the transverse temporal gyrus (Heschl's gyrus) of both hemispheres in response to pure tone stimuli using cross-correlation analysis (P < 0.001). Bilateral hemispheric activation was observed in all subjects and there was a trend towards contralateral HG activation to the stimulated ear. CONCLUSION: These results demonstrate directly that fMRI is a new and useful imaging technique to study the complex auditory cortex and it will have potential clinical applications in the next future (AU)