Mapping the spatial visual attention mobilized by the ventral visual pathway

Author(s)

Adriana Medeiros Sales de Azevêdo

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2010-02-26

Examining board members

Ronald Dennis Paul Kenneth Clive Ranvaud; Luiz Roberto Giorgetti de Britto; Edgard Morya

• Advisor: Ronald Dennis Paul Kenneth Clive Ranvaud

Abstract

Visual processing has two pathways: Dorsal (localization/movement) mobilized for Simple Reaction Time tasks (SRT); Ventral (shape/color) mobilized for Choice Reaction Time tasks (CRT). We presented an approach to investigate visual attentional resources. Usual psychophysical methods sample many times few points. We opted to sample many points few times aiming to enlarge the sampled visual field. It was obtained major details of the attentional distribution. Voluntary attention task: I. SRT, for Dorsal pathway. Stimuli were different in color answered triggering a button, in a diffusion attention paradigm. II. CRT, for Ventral pathway. Stimuli were two different color answered by triggering a button for each color in a diffuse paradigm. III. CRT, experimental subject instructed to focus attention in two frames for a splitted attention paradigm. Results showed anisotropy in the diffuse attention distribution, favouring the lower hemifield for SRT and superior hemifield for CRT. The splitted attention paradigm evidenced the presence of two attentional focuses. (AU)