Binocular%20Rivalry%20and%20Visual%20Awareness%20in%20Human%20Extrastriate%20Cortex

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Binocular Rivalry and Visual Awareness in Human
Extrastriate Cortex

• Frank Tong, Ken Nakayama, J. Thomas Vaughan, and
  Nancy KanwisherDepartment of PsychologyHarvard
  UniversityNeuron, Vol. 21 753-759, October 1998

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Talk Outline
B A C K G R O U N D
M E T H O D S
R E S U L T S
C O N C L U S I O N
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B A C K G R O U N D
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Monocular Rivalry Examples
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Binocular Rivalry
J
Brain
1 Perception
2 Stimuli
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Binocular Rivalry
Brain
1 Perception
2 Stimuli
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Where is rivalry resolved?
???

• First guess LGN or PVC
• But, single-unit recordings in monkeys

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Where is rivalry resolved?
FFAPPA
FFA Fusiform Face Area PPA Parahippocampal
Place Area
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M E T H O D S
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Creating binocular rivalry
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fMRI Scans

• Localizer Scans
• Rivalry Scans
• Non-rivalry Scans

Four healthy right-handed human subjects, aged
20-39.
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1. Localizer Scans

• Alternating house and face stimuli
• Locate FFA and PPA

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Localizer Scan(In actual experiment, stimuli
were presented for 16 second intervals.)
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1. Localizer Scans

• Alternating house and face stimuli
• Locate FFA and PPA

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2. Rivalry Scans

• Present single rivalry-causing stimulus
• Record timing of subject-reported dominant percept

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Rivalry Scan
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2. Rivalry Scans

• Present single rivalry-causing stimulus
• Record timing of subject-reported dominant percept

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3. Non-rivalry Scans

• Alternating house and face stimuli
• Present stimuli in identical temporal sequence
  reported during rivalry scans

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Non-Rivalry Scan(Stimuli presented in same
sequence and duration as reported in rivalry
scan.)
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3. Non-rivalry Scans

• Alternating house and face stimuli
• Present stimuli in identical temporal sequence
  reported during rivalry scans

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R E S U L T S
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1. Localizer Scans
FFA Fusiform Face Area PPA Parahippocampal
Place Area
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Localizer Scans Raw Data
FFA Fusiform Face Area PPA Parahippocampal
Place Area
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Rivalry Scans Raw Data
FFA Fusiform Face Area PPA Parahippocampal
Place Area
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Averaged Transition Data
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Everything together
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C O N C L U S I O N
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What can we conclude?

• FFA PPA are confirmed.
• FFA PPA activity matches perception.
• And back to our original question

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Upper bound on rivalry resolution
FFAPPA
FFA Fusiform Face Area PPA Parahippocampal
Place Area
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Executive Summary
Where is rivalry resolved?
B A C K G R O U N D
Chic glasses fMRI.3 experiments.
M E T H O D S
FFA PPA respond the same for rivalry and
non-rivalry.
R E S U L T S
Rivalry is resolved before these stages of
processing.
C O N C L U S I O N
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Questions?
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(No Transcript)
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• Picture of cool guy in glasses taken from
  http//bill.innanen.com/ parkinsons/diary200110.sh
  tml

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Binocular Rivalry and Visual Awareness in Human
Extrastriate Cortex

• Frank Tong, Ken Nakayama, J. Thomas Vaughan,
  and Nancy KanwisherDepartment of
  PsychologyHarvard UniversityNeuron, Vol. 21
  753-759, October 1998

Presented by Stan James and Mayumi
Koguchi stan_at_wanderingstan.com koguchischoepf_at_tisc
ali.de
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Binocular Rivalry and Visual Awareness in Human
Extrastriate Cortex

• Frank Tong, Ken Nakayama, J. Thomas Vaughan, and
  Nancy KanwisherDepartment of PsychologyHarvard
  UniversityNeuron, Vol. 21 753-759, October 1998
• Presented by Stan James and Mayumi Koguchi
• stan_at_wanderingstan.com
• koguchischoepf_at_tiscali.de

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Executive Summary
Where is rivalry resolved? Stylish glasses,
fMRI FFA PPA respond the same for rivalry and
non. Rivalry is resolved before these stages of
processing.
B A C K G R O U N D
M E T H O D S
R E S U L T S
C O N C L U S I O N
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(No Transcript)
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2. Rivalry Scans Raw Data
FFA Fusiform Face Area PPA Parahippocampal
Place Area
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Still not convinced?
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Rivalry
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Binocular Rivalry
J
Brain
1 Perception
2 Stimuli