An event-related potentials analysis of endogenous orienting of attention with a variant of the spatial cueing task

• Grant number: 16/16915-6
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: February 10, 2017
• End date: February 09, 2018
• Field of knowledge: Humanities - Psychology - Physiological Psychology
• Principal Investigator: Gilberto Fernando Xavier
• Grantee: Elisa Mari Akagi Jordão
• Supervisor: George R. Mangun
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of California, Davis (UC Davis), United States
• Associated to the scholarship: 14/22703-6 - Endogenous orienting of attention in humans involves automatic and voluntary processes?, BP.DR

Abstract

Orienting of attention in humans is believed to occur in two different ways: endogenously (or voluntary) or exogenously (or automatic). In spatial cueing task, centrally presented symbolic cues would orient attention in a controlled (voluntary) manner that requires effort and takes more time (hundreds of milliseconds). However, recent studies show that automatic orienting may also occur when presenting central cues. The hypothesis is that the repeated pairing between central predictive cue and target (usually 80% of trials) correspond to a form of classical conditioning that contributes to an automatic orienting to the cued target. To test this hypothesis we developed a variant of the spatial cueing task with the insertion of a stimulus between cue and target, termed anchor, that needs to be reported at the end of each trial. This anchor would avoid cue-target association and be a temporal signal for orienting the attention to the cued location thus being a truly voluntary orienting. Behavioral studies are being conducted in order to verify the effect of voluntary orienting of attention in this task. However, it is difficult to understand the organization of perceptual and cognitive processes such as visual attention using only behavioral measures because highly similar or identical patterns of behavioral response could be produced by partially or wholly different underlying neural mechanisms. Therefore, many electrophysiological studies using Event-Related Potentials (ERP) analysis have investigated the mechanisms and time course of neural activity involved in endogenous orienting of attention. ERP components related to the processes occurring after cue presentation, i.e. attention orienting processes, were consistently observed in different experiments like Early Directing Attention Negativity (EDAN, 200 ms after cue), Anterior Directing Attention Negativity (ADAN, 300 ms after cue) both related to initiation of orienting of attention, and Late Directing Attention Positivity (LDAP, 500 ms after cue) related to preparatory activity in visual cortex. However, few ERP studies investigated the neural mechanisms related to the automatic orienting to symbolic central cues, and none investigated if these ERP components would be indeed related to a truly voluntary orienting of attention. The aim of the present study is to investigate ERP components correlates of voluntary orienting of attention processes using the developed task described before. For this, electroencephalography (EEG) will be recorded in different groups performing a task where cue-target association is avoided (voluntary orienting) or a task where the association occur (automatic orienting). Therefore, comparing the ERP components related to orienting processes in these distinct conditions could reveal variations of neural activity when automatic or voluntary orienting is required. It is expected, in the voluntary orienting group, that the EDAN, ADAN and LDAP components described before would show a temporal shift compared with automatic orienting group, i.e. the components would be observed at a longer period of time after cue presentation. Because if orienting is truly voluntary then it would take more time to occur. Also, there could be amplitude variation of the ADAN component between groups because this component is related to frontal control processes, a region also known to be involved in association processes. Therefore, group exposed to a condition avoiding cue-target association would show less increase of negative deflection of the ADAN component. (AU)