Notes
Slide Show
Outline
1
COMPARISON OF CORTICAL ACTIVITY AND OCULOMOTOR PERFORMANCE IN GAP, STEP AND MEMORY-GUIDED TASKS
  • M.W. Greenlee; J. Özyurt; P. DeSouza; P. West;               R. Weerda; R. Rutschmann


  • Cognitive Neuroscience, Dept. Psychology, University of Oldenburg, Germany
  • Cambridge Research Systems, Rochester, United Kingdom
2
Issues
  • Cortical control of saccadic eye movements
    • Visually guided vs. memory guided saccades
    • Latency of saccades
    • Task-specific differences in BOLD response
3
Methods
  • In-scanner monitoring of eye movements
    • High temporal resolution
    • Performance (errors)
    • Saccadic latency
    • Fixation behavior & blinks
4
MR-Eyetracker
  • IR-limbus reflection
  • MR compatible
  • High temporal resolution
5
Tasks
  • Step paradigm
6
Tasks
  • Step paradigm
7
Tasks
  • Step paradigm
8
Tasks
  • Step paradigm
9
Tasks
  • Step paradigm
10
Tasks
  • Gap paradigm
11
Tasks
  • Gap paradigm
12
Tasks
  • Gap paradigm
13
Tasks
  • Gap paradigm
14
Tasks
  • Gap paradigm
15
Tasks
  • Gap paradigm
16
Tasks
  • Gap paradigm
17
Tasks
  • Memory-guided paradigm
18
Tasks
  • Memory-guided paradigm
19
Tasks
  • Memory-guided paradigm
20
Tasks
  • Memory-guided paradigm
21
Tasks
  • Memory-guided paradigm
22
Tasks
  • Memory-guided paradigm
23
Tasks
  • Memory-guided paradigm
24
Tasks
  • Memory-guided paradigm
25
Tasks
  • Memory-guided paradigm
26
Visually guided vs. memory-guided
27
Saccade Amplitudes
  • Saccade amplitudes in Step, Gap and Memory-guided Tasks
28
Saccadic Reaction Times
  • SRTs in Step, Gap and Memory-guided Tasks
29
Saccadic Reaction Times
  • SRTs in Step, Gap and Memory-guided Tasks
30
Saccadic Reaction Times
31
Task related Errors
  • Errors in Step and Memory-guided Tasks
32
ROI-Analysis
  • FEF   (x,y,z: -50, -2, 50)
    • Step>rest: z = 6.2 (54)
    • Gap>rest: z = 9 (89)
    • M-G>rest: z = 12.7 (232)


  • SEF   (x,y,z: 4, -2, 66)
    • Step>rest: z = 7.4 (158)
    • Gap>rest: z = 8.5 (174)
    • M-G>rest: z = 13 (227)
33
ROI-Analysis
  • FO
    • Area 9   (x,y,z: 56, 18, -2)
    • Step > rest: z = 6 (22)
    • Gap > rest: z = 8.9 (160)
    • M-G > rest: z = 13.5 (307)
34
ROI-Analysis
  • Posterior parietal
    • Area 7  (x,y,z: -2, -60, 62)


    • Step > rest: z = 6.2 (136)
    • Gap > rest: z = 7.2 (168)
    • M-G > rest: z=11.8 (1290)
35
ROI-Analysis
  • STG   (x,y,z: 62, -56, 4)
    • Step > rest: z = 5.6 (77)
    • Gap > rest: z = 7.6 (462)
    • M-G > rest: z= 10.9 (927)
36
ROI-Analysis
  • AC (x,y,z: 2, 22, 40)
    • Step > rest:  --
    • Gap > rest:  --
    • M-G > rest: z= 8.9 (225)
37
ROI-Analysis
  • V1 (x,y,z:  0, -86, 0)
    • Step > rest: z = 5.6 (73)
    • Gap > rest: z = 5.7 (29)
    • M-G > rest: z = 7.2 (281)
38
Summary
  • SRTs in visually guided and memory-guided tasks
  • BOLD responses in:
    • FEF, SEF & FO increased during memory-guided
    • PP & STG increased during memory-guided
    • AC only active during memory-guided
    • V1 not significantly different