title: Premotor and occipital theta asymmetries as discriminators of memory- and stimulus-guided tasks.
abstract: The saccadic paradigm has been used to investigate specific cortical networks involving visuospatial attention. We examined whether asymmetry in theta and beta band differentiates the role of the hemispheres during the execution of two different prosacadic conditions: a fixed condition, where the stimulus was presented at the same location; and a random condition, where the stimulus was unpredictable. Twelve healthy volunteers (3 male; mean age: 26.25) performed the task while their brain activity pattern was recorded using quantitative electroencephalography. We did not find any significant difference for beta, slow- and fast-alpha frequencies for the pairs of electrodes analyzed. The results for theta band showed a superiority of the left hemisphere in the frontal region when responding to the random condition on the right, which is related to the planning and selection of responses, and also a greater activation of the right hemisphere during the random condition, in the occipital region, related to the identification and recognition of patterns. These results indicate that asymmetries in the premotor area and the occipital cortex differentiate memory- and stimulus-driven tasks.
authors: Brain Mapping and Sensory Motor Integration, Institute of Psychiatry of the Federal University of Rio de Janeiro (IPUB/UFRJ), Brazil; Institute of Applied Neuroscience (IAN), Rio de Janeiro, Brazil.
authors: Consuelo
authors: C
authors: Cartier
authors: Juliana
authors: J
authors: Bittencourt
authors: Caroline
authors: C
authors: Peressutti
authors: Sergio
authors: S
authors: Machado
authors: Flávia
authors: F
authors: Paes
authors: Alexander T
authors: AT
authors: Sack
authors: Luis F
authors: LF
authors: Basile
authors: Silmar
authors: S
authors: Teixeira
authors: José Inácio
authors: JI
authors: Salles
authors: Antonio Egidio
authors: AE
authors: Nardi
authors: Mauricio
authors: M
authors: Cagy
authors: Roberto
authors: R
authors: Piedade
authors: Oscar
authors: O
authors: Arias-Carrión
authors: Bruna
authors: B
authors: Velasques
authors: Pedro
authors: P
authors: Ribeiro
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D009044:Motor Cortex / Q000502:physiology*; D009778:Occipital Lobe / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D012438:Saccades / Q000502:physiology; D055815:Young Adult