Detecting single-target changes in multiple objective Tracking: The Case of Peripheral Vision

I choose a study on peripheral vision because you never really notice of often this part of the vision is used and its importance. Most sports and activities where you or an object are moving, peripheral vision is in use. It’s an important component of many instinctual brain functions including balance and predator awareness. 

In a study by Fehd and Seiffertt tried to figure out weather peripheral vision can be used to monitor multiple moving objects and to detect single target changes. The study was done by running two separate experiments on peripheral vision of the studied participants.  Peripheral vision or side vision, is seen on the side by the eye when looking straight ahead. The light sensitive lining at the back of the eye called the retina. Is packed with rods and cones, which receive light. Cones are sensitive to color and are packed in the center of the retina, therefore it is hard to distinguish the color of an object out the corner of the eye because there few cones. 

 

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In one set of experiments the researchers used 14 sports science students male and female. The students were individually tested on a screen used to display MOT (Multiple object tracking) test. MOT an experimental technique used to study how our visual system tracks multiple moving objectives. The test assessed how well students could track movement in numbers at different speeds when projected in the peripheral vision, also recall numbers viewed from memory.  

The results showed significant accuracy differences for three speed conditions. 6 degrees was the highest, followed by 9, and 12. Each speed condition differ in terms of response accuracy from each other. As a result this means the slower the object moved the more the target were correctly recalled by subjects. The experiment aimed to weather classical MOT finding on gaze patterns. Results show that the faster the objects move the more tracking accuracy was needed because of impairment.  

In another set of experiments by Fehd and Seiffertt tried to figure out how well peripheral vision can track of multiple objects. Aimed to weather subjects are able to respond to a target related changes in motion or form in MOT peripherally before gaze on its target. The gaze is when subjects steadily intently look at the target, instead of quick glance. The focus laid on the dynamics of gaze behavior as a function of monitoring object changes with peripheral vision. They used onset and offset gazes to test. By using gaze behavior assumptions made by theoretical models ion the role of MOT can be assessed more symmetrically. The data of the students were able to detect target motion changes. The result shows that for all the targets the gaze vector was closer to the centroid than to the respective targets. Meaning the peripheral vision looked at the center of targets instead of the whole target. Form changes were found to be detected significantly faster than motion changes.  

 

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In the end both tests prove that peripheral vision is most effective at visualizing, still objects. Also detecting form changes in an object is quicker then motion changes. From this test I learned the importance of the use of your peripheral vision. How it’s a differences in focus from gaze vector, the eye is always tracking.  Peripheral vision plays apart in our everyday vision and we don’t even notice it. 

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Reference:

Alvarez, G. A., & Franconeri, S. L. (2007). How many objects can you track? Evidence for a resource-limited attentive tracking mechanism. Journal of Vision, 7(13), 14:1–10. doi:10.1167/7.13.14

Bahrami, B. (2003). Object property encoding and change blindness in multiple object tracking. Visual Cognition, 10, 949–963.CrossRefGoogle Scholar