PSYCH 454 Lecture Notes - Lecture 21: Attentional Blink, Receptive Field
24 May 2018
School
Department
Course
Professor
Lect 21: Attention
Why do we need attention?
●Problem: too much info to simultaneously process everything in detail
●Solution: attention helps us only process important info in detail
What is “important” in a visual scene? (2 things govern→ stimulus salience and behavioral
goals)
●Stimulus salience: Item that significantly differs from neighboring items
○Especially in color, motion, orientation, size
■Ex: red line amongst green lines
○Stimulus driven → also called “bottom-up” or “exogenous” (comes from
periphery of sensory, outside)
●Behavioral goals: “top-down”, or “endogenous” process (sends info to sensory,
generated from within)
○Ex: goal is to find green, vertical line
●Both goals and salience guide our attention
○Top-down factors can override bottom-up factors
■Although hard to ignore new items or their sudden appearance
Different Types of Attention
●Spatial attention: Attention to a particular, attended location
○“Spotlight attention” → illumination/fixation of a point in space
○Gives enhanced processing of any info that falls within this field
●Feature-based attention: attention to a particular stimulus feature (color, orientation,
motion)
●Object-based attention: attention to a particular, whole object (ex: building)
○Attention can spread from cued to uncued locations of an object
●Temporal attention: attention over time
○Ex: attentional blink; second of two stimuli cannot be identified when it closely
follows (100-500 ms) the first → attention is deployed to the first stimulus
○Intentional blink paradigm
Overt and Covert Attention (types of spatial attention)
●Overt attention: attention is on whatever you are fixating upon
■Attention guides your gaze/eyes to important information
■Prior to cue, attention is on fixation point
●Covert attention: where you are looking differs from where you are attending
○Your attention is directed away from your gaze
Document Summary
Problem : too much info to simultaneously process everything in detail. Solution : attention helps us only process important info in detail. (2 things govern stimulus salience and behavioral goals) Stimulus salience : item that significantly differs from neighboring items. Stimulus driven also called bottom-up or exogenous (comes from. Behavioral goals : top-down , or endogenous process (sends info to sensory, periphery of sensory, outside) generated from within) Ex: goal is to find green, vertical line. Both goals and salience guide our attention. Although hard to ignore new items or their sudden appearance. Spatial attention : attention to a particular, attended location. Spotlight attention illumination/fixation of a point in space. Gives enhanced processing of any info that falls within this field motion) Feature-based attention : attention to a particular stimulus feature (color, orientation, Object-based attention : attention to a particular, whole object (ex: building) Attention can spread from cued to uncued locations of an object.
