title: [Attention: a complex cerebral function].
abstract: BACKGROUND
  Attention is a brain neurocognitive state of preparing what precedes perception and action, and is a result of cortical and subcortical networks. Attention selectively focuses our consciousness while filtering the constant flow of sensory information, selects competent parallel processing among stimuli and activates brain zones for ordering appropriate responses.
  
  
  METHODS
  From a neurofunctional point of view this paper reviews and describes attention as a brain function regulated by three interrelated systems: Alertness or arousal providing tonic attention, dependent on the mesencephalic reticular activating system and its connections: posterior attention or attention of perceptive selectivity that depends on zones of the right posterior parietal cortex and its connections; and, anterior attention or supervisory attention that regulates deliberate attention, and supported by zones of the anterior cingulate and lateral prefrontal cortex and the connections of the zones.
authors.affiliation: Departament de Psiquiatria i Psicobiologia Clínica, Universitat de Barcelona, España.
authors.forename: A
authors.initials: A
authors.lastname: Estévez-González
authors.forename: C
authors.initials: C
authors.lastname: García-Sánchez
authors.forename: C
authors.initials: C
authors.lastname: Junqué
mesh_terms: D001288:Attention / Q000502:physiology*; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D009415:Nerve Net / Q000502:physiology
vernacular_title: La atención: una compleja función cerebral.