Investigating the contribution of parallel processing to visual search performance according to the Target Contrast Signal Theory

Visually searching around our environment is a common behavior that underlies many tasks we do each day, such as searching the roadway while driving. But the attention demands of such a task can vary depending on the roadway condition: it can be very easy on rural roads, when there are fewer objects and cars, or it can be very difficult when driving in a city where there are many other vehicles. This ubiquitous search behavior is studied in the lab through the visual search paradigm. Contrary to the traditional notion of a pre-attentive stage that is based on saliency or target activation maps, Target Contrast Signal Theory (TCST) proposes that parallel processing in early vision involves evidence accumulation about how likely a given location is to contain the target in effort to reject items from further processing. The experiments presented and proposed in this thesis further our knowledge and understanding about this early parallel processing in visual search and allows us to extend previous findings of parallel processing to new tasks and applications. Chapter 1 serves as a general introduction into visual search and provides a discussion of TCST. Chapter 2 investigates the role of color affordance in visual search by equating stimuli color and luminance. Chapter 3 explores the relationship between this visual search efficiency and working memory, using TCST as the theoretical model to separate parallel processing from serial processing. Chapter 4 investigates the flexibility of early parallel processing, comparing a target discrimination task and a detection task, highlighting the variability between the two tasks, and interrogating how search is terminated with parallel processing.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Psychology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2020

Author dc:creator

• Madison, Anna M

Contributors dc:contributor

• Lleras, Alejandro
• Buetti, Simona
• Beck, Diane
• Wang, Ranxiao (Fances)
• Morrow, Dan

• Visual search
• Parallel processing

Statement dc:rights

• Copyright 2020 Anna Madison

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/108333

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/108333