Developmental rules of auditory event-related potentials of exogenous components:from children to adults / 第三军医大学学报

Objective To investigate the normal waveform,lantency and amplitude of auditory event-related potentials (ERPs) of exogenous components in children at different ages,and summarize the developmental rules and clinical perspectives of exogenous ERPs according to the International Federation of Clinical Neurophysiology (IFCN) Recommended Standards in 2009.Methods One hundred and thirty-six children aged from 3 to 17 years old (admitted in the departments from healthcare,orthopedics,general surgery,and respiratory and digestive diseases,and those recovered from respiratory infection and gastrointestinal infection),and healthy adults (from undergraduates of Chongqing medical university) were recruited in this study from 2008 to 2010.They were divided into 4 groups in accordance with their ages,that is,3 ～5,＞ 5 ～7,＞ 7 ～9,and ＞ 9 ～17 years old groups,and adult group (22 ～29 years old).ERPs were recorded from the midline site (Cz) with classical auditory Oddball paradigm.Each subject was tested twice or more to determine waveform repeatability.The overlapped graphs of ERPs under target and standard stimuli were obtained in the potentiometer.The exogenous ERPs,including P1,N1,P2 and N2,lantency and amplitude were measured.Results The latencies of exogenous ERPs under target and standard stimuli were shortened in a non-uniform manner with the increasing of age.No matter under target or standard stimuli,over 95％ of mean latencies of exogenous ERPs were within the range of 2SD.In addition to N1 component,the amplitude of P1,P2 and N2 components induced by target stimulus were in a trend of increased first and then decreased with the increasing of age.Compared with the children,the amplitude was much lower in the adults and adolescents (P ＜ 0.05).The N2 component induced by target stimulus was absent among 95％ healthy adults.The Standard deviations of amplitudes of exogenous components were great in all aged groups,indicating significant individual differences.Conclusion The latencies of exogenous ERPs are shortened with the increasing of age.Target stimulus will produce more stable results than the standard stimulus,and the ERPs under target stimulus can reflect the primary auditory cortex function of temporal lobe,and are independent on patients' cooperation.

Time-varying source analysis of auditory-visual stimuli evoked event-related potentials / 国际生物医学工程杂志

Objective Dipole source analysis was employed to investigate the transient changes in brain mechanisms at earlier latencies.Methods Fourteen healthy volunteers were recruited in this research and evoked event-related potentials (ERPs) of unimodal and bimodal visual auditory stimuli were recorded by 64-electrodes electroencephalograph (EEG) recording system.All these earlier phases of the stimuli were divided into several subphases by specific time window for source analysis.Results The results showed that ERPs sources were mainly generated from visual and audio cortex,and there were changes in the location and strength of the dipole sources in each sub-phase.Conclusions The result of this study implies a serial processing of sensory information in human cortices in early phase of visual and auditory stimuli.

The Effect of Bilaterally Alternating Auditory Stimulations on the Episodic Memory Retrieval / 신경정신의학

OBJECTIVES: Previous research has shown that bilaterally alternating eye movements enhance episodic memory retrieval. This effect has been considered an important mechanism of the therapeutic effects of eye movement desensitization and reprocessing (EMDR) treatment. We conducted this study in order to test the hypothesis that bilaterally alternating auditory stimuli would also have similar effects on episodic memory retrieval. METHODS: Thirty eight right-handed subjects participated in this study. Subjects learned words, and then received bilaterally alternating auditory stimuli (as experimental stimuli) or unilateral auditory stimuli (as control stimuli). Subsequently, they performed recognition memory task. Recognition accuracy, response bias, and mean response to hits were used for evaluation of episodic memory retrieval. Repeated measures analysis of variance was performed for statistical analysis. RESULTS: There was no significant effect of experimental conditions in recognition accuracy, the response bias, and mean response time to hits. CONCLUSION: Unlike the previous positive results of bilaterally alternating eye movements, we did not observe an enhancing effect of bilaterally alternating auditory stimuli compared to unilateral auditory stimuli on episodic memory retrieval. This result suggests the possibility that the therapeutic mechanisms of EMDR might differ according to modalities of bilateral stimulation.

Auditive discrimination of equine gaits by parade horses Discriminación auditiva de pasos equinos por caballos de paso fino / Discriminación auditiva de pasos equinos por caballos de paso fino

The purpose of this study was to examine parade horses’ auditory discrimination among four types of equine gaits: paso-fino (“fine step”), trote-reunido (“two-beat trot”), trocha (“trot”), and galope-reunido (“gallop”). Two experimentally naïve horses were trained to discriminate the sound of their own gait (paso-fino or fine step), through an experimental module that dispensed food if the subject pressed a lever after hearing a sound reproduction of a particular gait. Three experimental phases were developed, defined by theperiod of exposure to the sounds (20, 10, and 5 seconds, respectively). Thechoice between pairs of sounds including the horse’s own gait (fine stepand two-beat trot; fine step and gallop; and fine step and trot) was reinforceddifferentially. The results indicate that the fine step horses are able todiscriminate their own gait from others, and that receptivity to their ownsounds could be included in their training regime.

Esta investigación buscó examinar la discriminación auditiva de cuatro pasos equinos: paso-fino, trote-reunido, trocha y galope-reunido. Dos caballos de paso fino colombiano, experimentalmente ingenuos, fueron entrenados para discriminar el sonido de su propio paso (paso-fino), a través de un modulo experimental que dispensó comida si el sujeto presionaba una palanca luego de escuchar la reproducción sonora de un paso particular. Se efectuaron tres fases experimentales, definidas por el período de exposición a los sonidos (20, 10 y 5 segundos respectivamente). Se reforzó diferencialmente la elección entre pares de sonidos que incluían el propio paso del caballo (paso-fino vs. trote-reunido; paso-fino vs. trocha; paso-fino vs. galope reunido). Los resultados indican que los caballos de paso fino son capaces de discriminar su propio paso de otros y que la receptividad a sus propios sonidos podría ser incluida en sus regímenes de entrenamiento, con el fin de evitar el uso de estimulación aversiva para tal fin.

Primacía visual:: transferencia ante el cambio de la relación entre estímulos * / Visual primacy: transfer under stimuli's relation chagge

Ninety subjects with different ages and school experience were trained on a zero-delay, second-order matching-to-sample task. The task consisted in the class identification of vegetables and animals (in any order) as living beings. Stimuli could be visual, auditory, or both in one of six possible arrays of second-order, sample, and comparison stimuli. Transfer tests changed the identity word relation, classified as objects, animals or vegetables. Transfer sessions involved test trials (1) with the same number; (2) fewer; or (3) more auditory stimuli than in training. One 7 years old student four 10 years old, seven 14 years old and fourteen college students learned the task when this included more visual than auditory stimuli. Fifteen subjects 14 years old of another sample obtained the training criterion and maintained it at transfer tests. The study points out the importance the visual stimulus had in this kind of task. The function of the scholar training is also discussed.

Se entrenó a 90 sujetos con grados escolares distintos mediante el procedimiento de igualación a la muestra de segundo orden con demora cero. El entrenamiento consistió en la clasificación de seres vivos igualando animales con vegetales o viceversa. Las palabras se presentaron de manera visual, auditiva o en ambas modalidades, generando seis arreglos de los estímulos de segundo orden, del estímulo muestra y de los estímulos de comparación. En las pruebas de transferencia el criterio de igualación se basó en la clasificación semántica de animales, objetos inanimados o vegetales. Se incluyeron tres pruebas de transferencia con igual, menor o mayor número de estímulos auditivos que los presentados en el entrenamiento. Los resultados mostraron que un alumno de 7 años, cuatro de 10, siete de 14 años y catorce sujetos de 17 años lograron el criterio del entrenamiento cuando éste incluyó un mayor número de estímulos visuales. En las pruebas de transferencia, un número menor de sujetos mantuvo el nivel de entrenamiento logrado. En una réplica efectuada en una muestra de sujetos de 14 años diferente a la anterior, se observó que independientemente de la condición experimental, 15 estudiantes de los 18 lograron el criterio del entrenamiento y lo mantuvieron en las pruebas de transferencia. El estudio muestra la primacía que tienen los estímulos visuales en este tipo de tareas y se discute el papel que parece tener el entrenamiento educativo.