title: [Theta/beta ratio (NEBA) in the diagnosis of attention deficit hyperactivity disorder].
abstract: BACKGROUND
  In July 2013, the US Food and Drug Administration approved the use of NEBA as the first device for the complementary evaluation of attention deficit hyperactivity disorder (ADHD). It is based on quantitative electroencephalogram (qEEG) and includes the standardised theta/beta ratio, the results of which were consistent with both the medical and psychological clinical evaluation. Likewise, it has proved to be a useful tool for determining whether the ADHD is primary, secondary or comorbid to another pathology. Yet, to date no publications have specified whether it is a total theta/beta ratio or theta/beta-1 and theta/beta-2. Additionally, no data are provided to be able to discriminate between diagnostic subtypes of ADHD.
  
  
  OBJECTIVE
  To quantify the theta/beta ratios, by means of qEEG, in a sample of patients from the Rio de la Plata area with a main confirmed diagnosis of ADHD, in order to compare the neurophysiological patterns according to the diagnostic subtypes.
  
  
  METHODS
  We used a randomised stratified sample of 62 subjects of both sexes, with ages between 8 and 17 years, distributed into two groups, depending on the diagnostic subtype: attention deficit subtype of ADHD (n = 31) and the combined subtype of ADHD (n = 31).
  
  
  RESULTS
  High theta/beta-1 and theta/beta-2 ratios were confirmed in the Cz region, being higher than the ratios in the C3 and C4 areas. Moderate and statistically significant differences were found between the two subtypes only in the beta-1 band in the occipital regions. The analysis of the interhemispheric coherence suggests an association of the power peak crossed with the diagnostic subtype, which is the fastest peak (10 Hz) for the combined subtype. No important differences are found on analysing the phase spectra or the theta/beta ratios.
  
  
  CONCLUSIONS
  Although the scientific literature, especially the NEBA system, highlights the importance of the theta/beta ratio in the differential diagnosis of ADHD in control samples and other neurodevelopmental disorders, a distinction must be made between beta-1 and beta-2.
authors.affiliation: Laboratorio para el estudio de las Funciones Superiores (LAFUN), Buenos Aires, Argentina.
authors.forename: Iván D
authors.initials: ID
authors.lastname: Delgado-Mejía
authors.forename: M Luisa
authors.initials: ML
authors.lastname: Palencia-Avendaño
authors.forename: Carolina
authors.initials: C
authors.lastname: Mogollón-Rincón
authors.forename: Máximo C
authors.initials: MC
authors.lastname: Etchepareborda
mesh_terms: D000293:Adolescent; D000465:Algorithms; D001289:Attention Deficit Disorder with Hyperactivity / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology; D001611:Beta Rhythm; D002648:Child; D004292:Dominance, Cerebral; D005260:Female; D006801:Humans; D008297:Male; D011897:Random Allocation; D012494:Sampling Studies; D013826:Theta Rhythm