1. Brian White Centre for Neuroscience Studies Queen’s, Kingston, Ontario, Canada Brian White Centre for Neuroscience Studies Queen’s, Kingston, Ontario, Canada The Representation of Visual Salience in the Superior Colliculus June 9 th, 2012

2. Oculomotor Circuit SCs = Superior Colliculus Superficial Layers SCi = Superior Colliculus Intermediate Layers T HALAMUS SCs SCi B RAINSTEM F RONTAL P ARIETAL F RONTAL P ARIETAL O CCIPITAL R ETINA

3. Aim Directly test whether the SC shows evidence of a sensory-driven saliency map i.e., higher-order visual process associated with computation of visual salience which takes into account feature-specific spatial interactions between stimuli across the entire visual field

4. Experiment 1 We compared visually evoked SC activation across three task irrelevant stimulus conditions single item, popout, conjunction Monkey’s task was to saccade to goal-related stimulus that ran orthogonal to the RF, where the salient item appeared

5. Task

6. (i) Single item cond (ii) Popout cond (iii) Conjunction cond

7. (i) Single item cond (ii) Popout cond (iii) Conjunction cond

8. (i) Single item cond (ii) Popout cond (iii) Conjunction cond

9. Abrupt onset Saccade

10. Abrupt onset Saccade + single item in RF

11. + Abrupt onset Saccade single item in RF

12. + Abrupt onset Saccade single item at anti- location

13. Abrupt onset Saccade + popout stimulus in RF

14. Abrupt onset Saccade + popout stimulus at anti- location

15. Abrupt onset Saccade + conjunction condition

16. 0-1mm (SCs) N=14 SC Depth 1-3mm (SCi) N=9 Popout in RF Popout anti-location Conjunction Single item in RF Single item anti-location * *

17. SCs SCi Single item in RF Single item anti-loc Popout item in RF Popout item anti-loc Conjunction Local field potentials (LFP)

18. Experiment 2 Same as Exp 1 except the RF was dragged over salient item via a pursuit eye movement. Same three conditions single item, popout, conjunction

19. Pursuit

20. N=19 SCs neurons Single item in RF

21. N=19 SCs neurons Single item in RF

22. N=19 SCs neurons Single item at anti location

23. N=19 SCs neurons Popout stimulus in RF

24. N=19 SCs neurons Popout stimulus at anti location

25. N=19 SCs neurons Conjunction condition

26. N=14 SCi neurons

27. Summary SC neurons (and LFPs) showed greater visual activation for popout relative to conjunction and anti-popout conditions, even though the stimuli were task irrelevant. This difference emerged after the initial visual transient. A similar pattern was observed previously in V4 (Burrows & Moore, 2009), and LIP (Arcizet, Mirpour & Bisley 2011). This difference was greatest for neurons within the dorsal most 1mm of the SC surface (i.e., the superficial visual layers) where the predominant inputs arise from visual cortex, not parietal/frontal cortices.

28. Oculomotor Circuit SCs = Superior Colliculus Superficial Layers SCi = Superior Colliculus Intermediate Layers F RONTAL P ARIETAL F RONTAL P ARIETAL B RAINSTEM O CCIPITAL T HALAMUS SCs SCi

29. Oculomotor Circuit SCs = Superior Colliculus Superficial Layers SCi = Superior Colliculus Intermediate Layers F RONTAL P ARIETAL F RONTAL P ARIETAL B RAINSTEM O CCIPITAL T HALAMUS saliency SCs SCi

30. Oculomotor Circuit SCs = Superior Colliculus Superficial Layers SCi = Superior Colliculus Intermediate Layers F RONTAL P ARIETAL F RONTAL P ARIETAL B RAINSTEM O CCIPITAL T HALAMUS saliency SCs SCi

31. Munoz Lab Doug Munoz Takuro Ikeda Collaborators: Laurent Itti David Berg Technical: Ann Lablans, Lindsey Duck, Donald Brien, Sean Hickman, Mike Lewis. Funding: CIHR, DARPA