title: Disentangling the attention network test: behavioral, event related potentials, and neural source analyses.
abstract: BACKGROUND
  The study of the attentional system remains a challenge for current neuroscience. The "Attention Network Test" (ANT) was designed to study simultaneously three different attentional networks (alerting, orienting, and executive) based in subtraction of different experimental conditions. However, some studies recommend caution with these calculations due to the interactions between the attentional networks. In particular, it is highly relevant that several interpretations about attentional impairment have arisen from these calculations in diverse pathologies. Event related potentials (ERPs) and neural source analysis can be applied to disentangle the relationships between these attentional networks not specifically shown by behavioral measures.
  
  
  RESULTS
  This study shows that there is a basic level of alerting (tonic alerting) in the no cue (NC) condition, represented by a slow negative trend in the ERP trace prior to the onset of the target stimuli. A progressive increase in the CNV amplitude related to the amount of information provided by the cue conditions is also shown. Neural source analysis reveals specific modulations of the CNV related to a task-related expectancy presented in the NC condition; a late modulation triggered by the central cue (CC) condition and probably representing a generic motor preparation; and an early and late modulation for spatial cue (SC) condition suggesting specific motor and sensory preactivation. Finally, the first component in the information processing of the target stimuli modulated by the interaction between orienting network and the executive system can be represented by N1.
  
  
  CONCLUSIONS
  The ANT is useful as a paradigm to study specific attentional mechanisms and their interactions. However, calculation of network effects is based in subtractions with non-comparable experimental conditions, as evidenced by the present data, which can induce misinterpretations in the study of the attentional capacity in human subjects.
authors.affiliation: Psychophysiology Unit (Lab B508), Department of Experimental Psychology, Faculty of Psychology, University of Seville Seville, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Galvao-Carmona
authors.affiliation: Laboratory for Clinical Neuroscience, Centre of Biomedical Technology (CTB), Technical University of Madrid (UPM) Madrid, Spain.
authors.forename: Javier J
authors.initials: JJ
authors.lastname: González-Rosa
authors.affiliation: Psychophysiology Unit (Lab B508), Department of Experimental Psychology, Faculty of Psychology, University of Seville Seville, Spain.
authors.forename: Antonio R
authors.initials: AR
authors.lastname: Hidalgo-Muñoz
authors.affiliation: Multiple Sclerosis Unit, Virgen Macarena University Hospital Seville, Spain.
authors.forename: Dolores
authors.initials: D
authors.lastname: Páramo
authors.affiliation: Department of Physiotherapy, Faculty of Nursing, University of Seville Seville, Spain.
authors.forename: María L
authors.initials: ML
authors.lastname: Benítez
authors.affiliation: Multiple Sclerosis Unit, Virgen Macarena University Hospital Seville, Spain.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Izquierdo
authors.affiliation: Psychophysiology Unit (Lab B508), Department of Experimental Psychology, Faculty of Psychology, University of Seville Seville, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Vázquez-Marrufo
keywords: ANT; CNV; P300; alerting; attention; neural networks; orienting; source analysis