Visuospatial information processing load and the ratio between parietal cue and target P3 amplitudes in the Attentional Network Test.
In ERP studies of cognitive processes during attentional tasks, the cue signals containing information about the target can increase the amplitude of the parietal cue P3 in relation to the 'neutral' temporal cue, and reduce the subsequent target P3 when this information is valid, i.e. corresponds to the target's attributes. The present study compared the cue-to-target P3 ratios in neutral and visuospatial cueing, in order to estimate the contribution of valid visuospatial information from the cue to target stages of the task performance, in terms of cognitive load. The P3 characteristics were also correlated with the results of individuals' performance of the visuospatial tasks, in order to estimate the relationship of the observed ERP with spatial reasoning. In 20 typically developing boys, aged 10-13 years (11.3±0.86), the intelligence quotient (I.Q.) was estimated by the Block Design and Vocabulary subtests from the WISC-III. The subjects performed the Attentional Network Test (ANT) accompanied by EEG recording. The cued two-choice task had three equiprobable cue conditions: No cue, with no information about the target; Neutral (temporal) cue, with an asterisk in the center of the visual field, predicting the target onset; and Spatial cues, with an asterisk in the upper or lower hemifield, predicting the onset and corresponding location of the target. The ERPs were estimated for the mid-frontal (Fz) and mid-parietal (Pz) scalp derivations. In the Pz, the Neutral cue P3 had a lower amplitude than the Spatial cue P3; whereas for the target ERPs, the P3 of the Neutral cue condition was larger than that of the Spatial cue condition. However, the sums of the magnitudes of the cue and target P3 were equal in the spatial and neutral cueing, probably indicating that in both cases the equivalent information processing load is included in either the cue or the target reaction, respectively. Meantime, in the Fz, the analog ERP components for both the cue and target stimuli did not depend on the cue condition. The results show that, in the parietal site, the spatial cue P3 reflects the processing of visuospatial information regarding the target position. This contributes to the subsequent "decision-making", thus reducing the information processing load on the target response, which is probably reflected in the lower P3. This finding is consistent with the positive correlation of parietal cue P3 with the individual's ability to perform spatial tasks as scored by the Block Design subtest.
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Dimitri M
DM
Abramov
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Monique
M
Pontes
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Adailton T
AT
Pontes
Department of Physiology, Federal University of Juiz de Fora, Campus UFJF - ICB, Juiz de Fora, MG 36036-900, Brazil.
Carlos A
CA
Mourao-Junior
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Juliana
J
Vieira
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Carla
C
Quero Cunha
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Tiago
T
Tamborino
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Paulo R
PR
Galhanone
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil.
Leonardo C
LC
deAzevedo
Laboratory of Neurobiology and Clinical Neurophysiology, National Institute of Women, Children and Adolescents Health Fernandes Figueira, Oswaldo Cruz Foundation (FIOCRUZ), Av. Ruy Barbosa, 716, Flamengo, Rio de Janeiro, RJ 22250-020, Brazil. Electronic address: vlad.v@iname.com.
Vladimir V
VV
Lazarev
D000293:Adolescent; D001288:Attention; D002648:Child; D003463:Cues; D004569:Electroencephalography; D018913:Event-Related Potentials, P300; D006801:Humans; D008297:Male; D010296:Parietal Lobe / Q000502:physiology*; D065855:Spatial Processing; D014796:Visual Perception
Attentional Network Test; Cueing of target; Event related potentials; P3; Parietal cortex; Visuospatial information processing