[Is cochlear processing involved in language disorders?]. / El procesamiento coclear está involucrado en los problemas de lenguaje?

INTRODUCTION: Otoacoustic emissions are evidence of the existence of an active process in the cochlea, and the motility of the outer hair cells means that they can change the cochlear mechanical response. We believe that incorrect processing of the sounds of language in the cochlea can result in impaired language processes. SUBJECTS AND METHODS: Data were collected from the patient record; neurological, visual and auditory examination; Weschler intelligence scale; initial language test (ILT); brainstem auditory evoked potentials (BAEPs) and transient otoacoustic emissions. The results of the ILT were used to form three groups: controls, pathological and pathological with normal ILT. RESULTS: All the children presented a response at 20 dB by means of the BAEPs. In the transient otoacoustic emissions, Student's t test was conducted between the right and the left ear for total reproducibility and reproducibility at different band frequencies within each group. No significant differences were observed. The same test was carried out between groups (controls versus pathological, controls versus pathological with normal ILT, and pathological versus pathological with normal ILT) in the right and left ears; no significant differences were found in the total reproducibility for the two ears. No significant differences were found in the reproducibility at different frequency bands for the left ear, but some were found in the case of the right ear. CONCLUSIONS: Laterality from the periphery exists for language processing and if this process fails to perform correctly, due to malfunctioning of the outer hair cells, language may be affected.

¿El procesamiento coclear está involucrado en los problemas de lenguaje? / Is cochlear processing involved in language disorders?

Introducción. Las emisiones otoacústicas evidencian la existencia de un proceso activo en la cóclea y la motilidad de las células ciliadas externas implica que éstas pueden cambiar la respuesta mecánica coclear. Creemos que un procesamiento inapropiado de los sonidos del lenguaje en la cóclea puede dar como resultado una alteración de los procesos del lenguaje. Sujetos y métodos. Se realizó historia clínica, exploración neurológica, visual y auditiva, escala de inteligencia de Wechsler, prueba de lenguaje inicial (PLI), potenciales evocados auditivos de tallo cerebral (PEATC) y emisiones otoacústicas transitorias. Con los resultados de la PLI se formaron tres grupos: controles, patológicos y patológicos con PLI normal. Resultados. Todos los niños presentaron respuesta a 20 dB por medio de los PEATC. En las emisiones otoacústicas transitorias se realizó la t de Student entre el oído derecho y el izquierdo para la reproducibilidad total y la reproducibilidad por banda de frecuencia dentro de cada grupo, sin observarse diferencias significativas Se efectuó la misma prueba entre los grupos (controles frente a patológicos, controles frente a patológicos con PLI normal y patológicos frente a patológicos con PLI normal) en el oído derecho e izquierdo, sin encontrarse diferencias significativas en la reproducibilidad total para ambos oídos. No se hallaron diferencias significativas en la reproducibilidad por bandas de frecuencia para el oído izquierdo, pero sí para el oído derecho. Conclusión. Existe una lateralidad desde la periferia para el procesamiento del lenguaje y si este proceso no es adecuado, por fallos en la función de las células ciliadas externas, el lenguaje puede verse afectado (AU)

Introduction. Otoacoustic emissions are evidence of the existence of an active process in the cochlea, and the motility of the outer hair cells means that they can change the cochlear mechanical response. We believe that incorrect processing of the sounds of language in the cochlea can result in impaired language processes. Subjects and methods. Data were collected from the patient record; neurological, visual and auditory examination; Weschler intelligence scale; initial language test (ILT); brainstem auditory evoked potentials (BAEPs) and transient otoacoustic emissions. The results of the ILT were used to form three groups: controls, pathological and pathological with normal ILT. Results. All the children presented a response at 20 dB by means of the BAEPs. In the transient otoacoustic emissions, Student’s t test was conducted between the right and the left ear for total reproducibility and reproducibility at different band frequencies within each group. No significant differences were observed. The same test was carried out between groups (controls versus pathological, controls versus pathological with normal ILT, and pathological versus pathological with normal ILT) in the right and left ears; no significant differences were found in the total reproducibility for the two ears. No significant differences were found in the reproducibility at different frequency bands for the left ear, but some were found in the case of the right ear. Conclusions. Laterality from the periphery exists for language processing and if this process fails to perform correctly, due to malfunctioning of the outer hair cells, language may be affected (AU)

[Evaluation of the motor behavior in rats with cortical ablation]. / Caracterizacion de la conducta motora en ratas con ablacion cortical.

INTRODUCTION: The cortical ablation has been used as an experimental model in order to study the basic mechanisms of functional recovery. However, there is not data concerning to the injury effects on the motor and somatosensorial behavioral manifestations that allow us to categorize such sequels as a hemiplegic model. MATERIALS AND METHODS: We used 35 male Wistar rats (280-300 g) allocated in two groups: control (n = 17) and brain injured by cortical ablation (n = 18). Previously trained, basal recordings of the footprint and motor and somatosensorial assessment were performed in the rats before surgery. The behavioral tests were performed again 6 hours after surgery and the spontaneous ambulatory activity was also evaluated. RESULTS AND CONCLUSIONS: It was observed a decrease in the stride's length and an increase in the stride's angle and in the motor deficit, while the somatosensorial assessment and spontaneous ambulatory activity were not affected. These findings are discussed in function of the motor features of the hemiparetic sequels in humans.

Caracterización de la conducta motora en ratas con ablación cortical / Evaluation of the motor behavior in rats with cortical ablation

Introducción. El modelo de ablación cortical en ratas se ha utilizado para estudiar los mecanismos básicos de recuperación funcional, pero no hay datos respecto a los efectos de la lesión sobre las manifestaciones conductuales motoras y somatosensoriales que permitan categorizar estas secuelas como un modelo de hemiplejía. Materiales y métodos. Se utilizaron 35 ratas machos Wistar (280-300 g), distribuidas en dos grupos: control (n = 17) y con lesión cerebral por ablación cortical(n = 18). Previo entrenamiento, se tomaron registros de la impresión de la huella y de las evaluaciones motora y somatosensorial antes de la cirugía de lesión. Seis horas después de la lesión se realizaron nuevamente las pruebas conductuales y se registró la actividad ambulatoria espontánea. Resultados y conclusiones. Se encontró que la lesión disminuye la longitud e incrementa el ángulo de la zancada y el déficit motor, sin afectar los aspectos somatosensoriales ni la actividad ambulatoriaespontánea. Estos hallazgos se discuten en función de las características motoras de las secuelas hemiparéticas comunicadas en humanos

Introduction. The cortical ablation has been used as an experimental model in order to study the basic mechanismsof functional recovery. However, there is not data concerning to the injury effects on the motor and somatosensorial behavioral manifestations that allow us to categorize such sequels as a hemiplegic model. Materials and methods. We used 35 male Wistarrats (280-300 g) allocated in two groups: control (n = 17) and brain injured by cortical ablation (n = 18). Previously trained, basal recordings of the footprint and motor and somatosensorial assessment were performed in the rats before surgery. The behavioral tests were performed again 6 hours after surgery and the spontaneous ambulatory activity was also evaluated.Results and conclusions. It was observed a decrease in the stride’s length and an increase in the stride’s angle and in the motor deficit, while the somatosensorial assessment and spontaneous ambulatory activity were not affected. These findings arediscussed in function of the motor features of the hemiparetic sequels in humans

[Brainstem auditory evoked potentials and vertex potentials in 5-year-old children with defective articulation of the phonemes /l/, /r/, /rr/ and /s/]. / Potenciales evocados auditivos de tallo cerebral y potenciales de vertice en ninos de 5 anos con fallos articulatorios para los fonemas /l/, /r/, /rr/ y /s/.

AIMS: In children with articulatory defects it is important to evaluate the central auditory level. We compared the results of the interwave intervals of brainstem auditory evoked potentials (BAEP) at 80 dB SPL (sound pressure level) and the latencies of the waves of long latency auditory evoked potentials (LLAEP) (vertex) in 5-year-old children with articulatory defects for /l/, /r/, /rr/ and /s/, and in controls. SUBJECTS AND METHODS: Fifty cases of 5-year-old children of both sexes were evaluated; 25 had articulatory defects and 25 with no articulatory defects were used as controls. Melgar's articulation test was applied to both groups. The following aspects were considered in the two groups: normal bilateral audition by means of tone audiometry, tympanometry and the revised Wechsler Intelligence Scale for preschool and primary school children, which were normal; there was no history of neurological damage. Interwave intervals for waves I-III, I-V and III-V of the BAEP and the latencies of the LLAEP (vertex) were evaluated. RESULTS: Data were analysed using SPSS 12, and descriptive statistics and Student's t test were carried out to appraise the differences between the two groups. No differences were found between the control group and the study group. CONCLUSIONS: It is important to determine whether children with articulatory defects have alterations in the auditory receptor or in their central auditory function. It can be concluded that the variables analysed in the two groups behave in the same way; no significant differences were found, which suggests that neither the auditory receptor nor the central auditory function are affected in the study group. Further studies are to be conducted to investigate the meaning of the difference in central nervous conduction between the two afferences in the study group.