chapter 6 notes.docx - PSYS 368 Sensation and Perception...

This preview shows page 1 - 3 out of 9 pages.

PSYS 368 Sensation and Perception Chapter 6: Visual Attention Scanning a Scene - Visual scanning – looking from place to place Fixation Saccadic eye movement - Overt attention involves looking directly at the attended object. - Covert attention refers to attention without looking. What Directs Our Attention? - Characteristics of the scene: Visual salience: areas of stimuli that attract attention due to their properties Color, contrast, and orientation are relevant properties. - Attentional capture properties of a stimulus grab attention, seemingly against a person’s will sudden movement, loud sounds warn us of danger Cognitive Factors - Picture meaning and observer knowledge Scene schema: prior knowledge about what is found in typical scenes Fixations are influenced by this knowledge - Experiment by Shinoda et al. Observers’ fixations were measured during computer simulated driving. Scan path of a person freely viewing a picture. Fixations are indicated by the yellow dots and saccadic eye movements by the red lines. Notice that this person looked preferentially at areas of the picture such as the statues but ignored areas such as the water, rocks, and buildings.
PSYS 368 Sensation and Perception Chapter 6: Visual Attention They were more likely to detect stop signs when they were at intersections They have learned that this is where stop signs are typically placed. - One way to show that where we look isn’t determined only by saliency is by checking the eye movements of the subject. Meaning likely has attracted attention - Attention can be influenced by a person’s goals. Task-Related Knowledge - Determine where people look as they carry out tasks, prepare for action - Timing of when people look at specific places is determined by the sequence of actions involved in the task. - Just in time strategy What Are the Benefits of Attention? - Spatial attention: attention to specific locations - Experiment by Posner (1978) et al. Observers looked at a fixation point. Precueing with an arrow indicated on which side a stimulus was likely to appear. Stimuli appeared that were consistent (valid trial) or inconsistent (invalid trial) with the cue. Task was to push button when a target square was seen. Attention Speeds Responding - Results of Posner experiment showed that observers responded fastest on valid trials. - Posner believed these results showed that information processing is most efficient where attention is directed.

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture