ABSTRACT
Los potenciales evocados de corteza prometen ser una herramienta útil en la evaluación de las funciones auditivas, proporcionando información sobre la funcionalidad e integridad de estructuras auditivas centrales. Dentro de sus posibles usos encontramos: estimación del umbral auditivo en adultos permitiendo una mayor precisión en comparación a otras técnicas electrofisiológicas, como herramienta de evaluación y seguimiento del entrenamiento auditivo, evaluación de la amplificación (especialmente utilizando estímulos complejos como el habla) relacionado con la detección del estímulo auditivo amplificado a nivel de la corteza y de la plasticidad auditiva como lo podría ser la monitorización de los cambios producidos por la estimulación auditiva. Sin embargo aún presentan algunas limitaciones que deben ser resueltas antes de ser incorporados dentro de la batería de pruebas audiológicas de uso clínico habitual, factores propios del sujeto, de la técnica utilizada y condiciones de evaluación (ej. diferentes tipos de audífonos) pueden hacer que estas respuestas presenten una variabilidad que podría dificultar su uso rutinario.
Cortical auditory evoked potentials have the potential to be a tool for the assessment of auditory functions, providing information on the functionality and integrity of central auditory structures. Among its possible uses are: hearing threshold estimation on adults that are more accurate compared to other electrophysiological techniques; a tool for assessment and monitoring of auditory training; evaluation of amplification (especially using complex stimuli such as speech) related to the detection of an amplified sound at the level of the auditory cortex; and monitoring plasticity via the changes produced by an auditory stimulation. However there are still some limitations to be resolved before incorporating cortical auditory evoked potentials in to the battery of audiological tests used in clinics. Factors related to the subject and the technique and assessment conditions (e.g. different types of hearing aids), may vary these responses and hinder its reliability and use.
Subject(s)
Humans , Auditory Cortex/physiology , Auditory Threshold/physiology , Evoked Potentials, Auditory/physiology , ElectrophysiologyABSTRACT
BACKGROUND AND OBJECTIVES: P1-N1-P2 complex reflecting pre-attentive processing of sound presents several temporally overlapping and spatially distributed neural sources in or near primary auditory cortex. This study investigated cortical evoked responses to the P1-N1-P2 complex to determine the perceptual contributions of the acoustic features. SUBJECTS AND METHODS: Eleven young native-speaking Korean adults with normal hearing participated. The stimuli were three bilabial, three alveolar, and three velar syllables, and each place of articulation had one lax, one tense, and one aspirate syllable as the manner of articulation. RESULTS: The results indicate the cortical responses to the velar syllables significantly differed from the bilabial and alveolar groups at the P1-N1 and N1-P2 interamplitude. However, there is no significant difference in the cortical responses between Korean lax and tense syllables, which is significant for English phonology in terms of voice onset time. Further, the cortical responses to aspirate syllables significantly differed from two other groups in the interamplitude, demonstrating that the /tha/ syllable had the largest response at N1-P2 interamplitude. CONCLUSIONS: Different speech sounds evoked different P1-N1-P2 patterns in the place and the manner of articulation in terms of interamplitude, but not of the latency and interlatency although further studies should be followed.