Use of single-electrode EEG in the evaluation of attention-deficit/hyperactivity disorder
*Correspondencia: Dra. Inmaculada Moreno García. Facultad de Psicología. Universidad de Sevilla. Camilo José Cela, s/n. E-41018 Sevilla.
E-mail: imgarcia@us.es
Introduction: Attention deficit/hyperactivity disorder (ADHD) maintains a diagnosis based on behavioral data despite its involvement in neuropsychophysiological models. The monopolar electroencephalography (EEG) record focused on differentiating children with ADHD versus controls based on a higher theta/beta ratio has been proposed as an alternative to objectify the diagnosis and guide neurofeedback-based intervention, but its results have been controversial.
Aim: To analyze the viability of a single electrode to detect differences in the main cerebral rhythms and especially in theta/beta ratio, in children diagnosed with ADHD, analyzing the differences by subtype, age, sex and type of experimental task.
Patients and methods: 92 children (range: 7-13 years) diagnosed with ADHD were evaluated in a monopolar EEG record on four experimental tasks (rest, reading, active listening and copying a figure). Seven measures on slow and fast EEG rhythms were obtained, plus theta/beta ratio.
Results: There were no differences by ADHD subtypes. The task of greatest cognitive demand obtained the highest wave amplitudes. Smaller participants and boys presented higher amplitudes in slow waves and in theta/beta ratio in all the experimental tasks, showing a greater tendency to attentional regulation problems.
Conclusion: Monopolar record and theta/beta ratio are a viable alternative in the clinical setting to complement the evaluation of ADHD.
Objetivo Analizar la viabilidad de un único electrodo para detectar diferencias en los principales ritmos cerebrales, y especialmente en la ratio theta/beta, en niños con diagnóstico de TDAH, analizando las diferencias por subtipo, edad, sexo y tarea.
Pacientes y métodos Se evaluó a 92 niños (rango: 7-13 años) con diagnóstico de TDAH en un registro de EEG monopolar sobre cuatro tareas (reposo, lectura, escucha activa y copiar una figura). Se obtuvieron siete medidas basadas en ritmos EEG lentos y rápidos, más la ratio theta/beta.
Resultados No hubo diferencias por subtipos de TDAH. La tarea de mayor demanda cognitiva obtuvo en general las amplitudes de onda más elevadas. Los participantes más pequeños y los varones presentaron en general una ratio theta/beta y amplitudes en las ondas lentas más elevadas en todas las tareas investigadas, y mostraron una mayor tendencia a problemas de regulación atencional.
Conclusión El registro monopolar y la ratio theta/beta son una alternativa viable en el ámbito clínico, al menos para complementar la evaluación del TDAH.