08 Perceiving Motion, Depth, and Size

08 Perceiving Motion, Depth, and Size - 1 Perceiving Motion...

Info icon This preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
10/18/2016 1 Perceiving Motion, Depth, and Size WEEK 8 At the beginning of action Lecture Outline Motion Reichardt circuits Corallary discharge Depth Cues Binocular disparity Size Size constancy Motion Motion No scene is static You move even when looking at a picture Your eyes move too Some movement is important (perceived) Other movement is not Movement within the scene is important Directs attention to changes in position Motion and your life Motion Real motion Object travels within scene 1 2 3 4 5 6 7 8
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
10/18/2016 2 not induced motion not apparent motion not motion aftereffects Two non-competing theories Reichardt circuit (a.k.a. Reichardt detector) Stationary eyes detect change in light position Corollary discharge Eyes in motion do NOT signal motion in scene Reichardt Circuit MOTION PERCEPTION MECHANISM Reichardt circuit Motion can be perceived when there is none Ex: apparent motion by flashing lights Hubel & Weisel (1965) Stop-end cortical cells (moving!) Cells in cortex responding to moving stimuli Even have preferred motion/direction Werner Reichardt 1969: Proposed a motion detection system Motion perceived Time = 0 1 2 3 4 10 11 12 13 14 15 16 17 18
Image of page 2
10/18/2016 3 5 6 7 8 9 10 Right to Left code Corollary Discharge Theory MOTION PERCEPTION MECHANISM Corollary Discharge Theory Reichardt circuits can explain motion of object passing over receptors Eyes move to follow an object Same relative position on retina Detection of eye muscles & passage of light on retina IDS: Image displacement signal MS: Motor signal CDS: Corollary discharge signal Three signals (IDS or CDS), not (IDS and CDS) Oculocentric motion: Eyes remain still, object passes through visual field Image displacement signal (IDS) Comparator: “Motion!” Egocentric motion Corollary discharge signal (CDS) Comparator: “Motion!” No motion Eyes move across still scene IDS & CDS Comparator: NO MOTION!
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern