Effects of Glaucoma

on path integration

in virtual reality

M.A. Safa Andac

M.Sc. Francie Kramer

Advisor: Prof. Dr. Michael Hoffmann

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 955590.

Outline

  • Damage to the Retinal Ganglion Cells
  • Progressive -- Blindness

BaCKGROUND: GLAUCOMA

Hoste A.M., 2003

Collett, T. S., & Graham, P. (2004)

Daga et al. (2017) - Navigation and Glaucoma

BaCKGROUND: NAVIGATION

Ability to keep track of a position

  • Vestibular system (Wallace et al., 2002)
  • Sensory flow (optic-flow) (Wylie et al., 1999)
  • Motor efference (Whishaw and Wallace, 2003)

https://www.bi.mpg.de/opticflow

BaCKGROUND: OPTIC FLOW

Safer

Manipulable

Immersive

BaCKGROUND: VIRTUAL REALITY

[H1] Glaucoma patients are slower than control group in path following

 

[H2] Participants move slower in an environment without optic flow

 

[H3] Control group benefit from optic flow more

HYPOTHESES

  • 29 participants (15 control, 14 glaucoma)
  • Environment with/out optic flow (w OF //  w/o OF)

METHODS

  1. Start from Point 0
  2. Move to Point 1
  3. Remember the position
  4. Move to Point 2 (second waypoint)
  5. Move to Point 3 (final waypoint)
  6. Point the position to be remembered

METHODS: PaTH iNTEGRATION

1

2

3

0

METHODS: PaTH iNTEGRATION

Measures

  • Travel Time
  • Pointing Task Duration
  • Error distance btw expected location - response location

Statistics

Mixed-ANOVA with factors

  • Group
  • Optic Flow
  • Group x Optic Flow
  1. Start from Point 0
  2. Move to Point 1
  3. Remember the position
  4. Move to Point 2 (second waypoint)
  5. Move to Point 3 (final waypoint)
  6. Point the position to be remembered

1

2

3

0

RESULTS

w/o OF

OF

Factor p
Group < 0.01
Optic Flow 0.03
Group x Optic Flow 0.14

w/o OF

OF

  • Control Group is faster
  • Groups are slow in the environment with optic flow

RESULTS

Factor p
Group < 0.01
Optic Flow 0.03
Group x Optic Flow 0.14

w/o OF

OF

w/o OF

OF

Factor p
Group 0.02
Optic Flow < 0.01
Group x Optic Flow 0.58

RESULTS

w/o OF

OF

w/o OF

OF

  • Control Group is faster
  • Groups are slow in the environment with optic flow
Factor p
Group 0.02
Optic Flow < 0.01
Group x Optic Flow 0.58

RESULTS

w/o OF

OF

w/o OF

OF

Factor p
Group 0.19
Optic Flow 0.02
Group x Optic Flow 0.04

RESULTS

Undershoot

Overshoot

w/o OF

OF

w/o OF

OF

Factor p
Group 0.19
Optic Flow 0.02
Group x Optic Flow 0.04

RESULTS

Undershoot

Overshoot

w/o OF

OF

w/o OF

OF

Factor p
Group 0.09
Optic Flow < 0.01
Group x Optic Flow 0.10

RESULTS

w/o OF

OF

w/o OF

OF

  • No difference between groups
  • Accuracy improves in the environment with optic flow

RESULTS

w/o OF

OF

w/o OF

OF

Factor p
Group 0.09
Optic Flow < 0.01
Group x Optic Flow 0.10
Factor p
Group 0.48
Optic Flow < 0.01
Group x Optic Flow 0.32

RESULTS

w/o OF

OF

w/o OF

OF

RESULTS

w/o OF

OF

w/o OF

OF

Factor p
Group 0.48
Optic Flow < 0.01
Group x Optic Flow 0.32

SUMMARY

[H1]  Glaucoma patients are slower than control group in path following

 

[H2] Participants move slower in an environment without optic flow

          Participants move slower in an environment with optic flow

 

[H3] Control group benefits from optic flow more

          All groups benefit from optic flow similar

  • Insecurity in glaucoma patients
  • Accuracy improvement in the environment with optic flow
    • Trade-off between time and accuracy

DISCUSSIOn

SECONDMENT

  • X position
  • Y position
  • Heading Direction

{

$$ x_t $$

  1. Is there a behavioral difference during navigation?
  2. Does optic flow affect the behavior?

Research Questions

1

2

3

ACKNOWLEDGEMENT

THANKS!

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 955590.

Aging, Cognition

& Technology Group

Visual Processing Lab

Matthieu Bernard

Vladislava Segen

Prof. Thomas Wolbers

Khaldoon Al-Nosairy

Gokulraj Prabhakaran

Yaxin Hu

Prof. Erhadt Barth

Genova-Presentation

By Safa Andac

Genova-Presentation

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