Cortical%20Representations%20of%20Attention%20and%20Salience

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Cortical Representations ofAttention and Salience

• James A. Mazer
• Department of Neurobiology
• Yale School of Medicine

Theoretical and Experimental Approaches to
Auditory and Visual Attention Banbury 2008
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The visual scenes can be complex during natural
vision
Cayo Santiago, MH, 2007
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Neural Representations of Attention and Salience

• Feature-based attention in area V4
• labeled lines or matched filters?
• (monkey single-unit)
• Maintaining spatial attention during eye
  movements
• spatiotopic or retinotopic maps for spatial
  attention?
• (human psychophysics)

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Attention and salience maps
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Attention and salience maps
feature-based attention
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Attention and salience maps
spatial attention
spatial cue target on right
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Attention and salience maps
spatial attention
spatial cue target on left
Koch, Itti, Heeger Reynolds
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1. Feature-based attention in area V4

• essential form processing relay station
• known anatomical and physiological target for
  top-down signals

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RSVP (slow) Rapid Search Visual Presentation
search target
stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
match!
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RSVP (slow) Rapid Search Visual Presentation
search target

stimulus stream
match!
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Tuning during RSVP Spike Triggered Average
Response (Hz)?
Orientation (deg)?
?t
?t
?t
?t
?t
?t
?t
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Tuning during RSVP Spike Triggered Average
Response (Hz)?
Orientation (deg)?
?t
?t
?t
?t
?t
?t
?t
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Tuning during RSVP Spike Triggered Average
Response (Hz)?
Orientation (deg)?
?t
?t
?t
?t
?t
?t
?t
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Tuning during RSVP Spike Triggered Average
Response (Hz)?
Orientation (deg)?
?t
?t
?t
?t
?t
?t
?t
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Tuning during RSVP Spike Triggered Average
Response (Hz)?
Orientation (deg)?
?t
?t
?t
?t
?t
?t
?t
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Tuning during RSVP Spike Triggered Average
Response (Hz)?
Orientation (deg)?
?t
?t
?t
?t
?t
?t
?t
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Interim Summary Feature-based attention V4

• feature-based attention affects
• shifts in preferred stimuli
• orientation-dependent gain changes
• changes in preferred stimulus could facilitate
  target detection, but not in any simple manner
  (some , some -)?
• modulation is maximal in a sub-population of
  broadly tuned V4 neurons, suggesting multiple
  intermingled populations within V4
• perhaps reflecting modulated and veridical
  subpopulations

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2. Maintaining spatial attention across eye
movements
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Spatial cueing 101
Posner (1980) and many others...
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Spatial cueing 101
valid cue
invalid cue
Posner (1980) and many others...
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Spatial cueing 101
faster more accurate more sensitive etc
invalid
valid
valid cue
invalid cue
Posner (1980) and many others...
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Neural representation of the cue?
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Neural representation of the cue?
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Neural representation of the cue?
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Neural representation of the cue?
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Neural representation of the cue?
Retinotopic (eye-centered)
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Neural representation of the cue?
Retinotopic (eye-centered)
Spatiotopic (head-centered)
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The representation of spatial attention

• Spatial attention survives intervening saccades
• Spatial attention is transiently maintained in
  retinotopic coordinates even when it hurts...
• The native representation of spatial attention
  appears to be retinotopic
• Simple model retinotopy recurrence...

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Conclusions

• feature-based attention
• feature-based in V4 can alter both gain and
  preferred stimulus
• orientation tuning changes are correlated with
  behavioral goals
• maintaining spatial attention across eye
  movements
• saccade planning and spatial cueing are
  dissociable (anti-premotor)
• spatial attention is intrinsically retintopic
• spatiotopic representations required active,
  top-down updating or remapping under voluntary
  control

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Acknowledgements
Mazer Lab Jonathan Touryan Monica Cano
Vinas Julie Golomb Matt Krause
Marvin Chun (Yale Psychology)