Decision-Related Activity in Human Visual Cortex during Perceptual Suppression

Decision-Related Activity in Human Visual Cortex during Perceptual Suppression - Decision-Related Activity in Visual Cortex

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

NL-OMON

Registry ID

NL-OMON34421

Enrollment

Registered

2010-12-13

Start date

2010-12-14

Completion date

Unknown

Last updated

2024-11-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

The study is basic research that does not address any condition. Not applicable

Interventions

None listed

Eligibility

Age

18 Years to 99 Years

Inclusion criteria

Inclusion criteria: Young, healthy adults. Age range 18-40 years. Experienced participants in psychophysical and neuroimaging experiments. Written informed consent. Normal or corrected-to-normal vision.

Exclusion criteria

Exclusion criteria: Significant neurological or psychiatric history (in particular, epilepsy). Significant visual disturbance. Claustrophobia. Metal items attached to or inside the volunteers* body that cannot be removed.

Design outcomes

Primary

Measure	Time frame
Based on our previous fMRI (Donner et al, Journal of Neuroscience, 2008) and MEG (Donner et al, Current Biology, 2009) results, we expect the following modulations of cortical activity to occur around the time of the subjects* behavioral (button press) report of the target disappearance: (1) A decrease of the specific response to the target in the visual cortex. This decrease will be specific to the cortical representation of the target stimulus, thus confined to the contralateral hemisphere, and it will precede subjects* behavioral report. (2) An increase of activity in motor cortex contralateral to the upcoming button press that reflects subjects* evolving plan to make the perceptual report. (3) A global response decrease throughout visual cortex, be expressed throughout both hemispheres. We predict that this global response modulation will succeed both response components (1) and (2), as well as subjects* behavioral report. We will interpret the target-specific response decrease in visual cortex (1) as the neural basis of the subjective target disappearance, the motor build-up activity (2) as a correlate of subjects* subsequent perceptual decision, and the global response decrease in visual cortex (3) as a feedback signal re-entering early visual cortex. Specifically, based on the latencies relative to (2), we may conclude that this global modulation in visual cortex is triggered by the preceding perceptual decision.	—

Measure

Time frame

Based on our previous fMRI (Donner et al, Journal of Neuroscience, 2008) and MEG (Donner et al, Current Biology, 2009) results, we expect the following modulations of cortical activity to occur around the time of the subjects* behavioral (button press) report of the target disappearance: (1) A decrease of the specific response to the target in the visual cortex. This decrease will be specific to the cortical representation of the target stimulus, thus confined to the contralateral hemisphere, and it will precede subjects* behavioral report. (2) An increase of activity in motor cortex contralateral to the upcoming button press that reflects subjects* evolving plan to make the perceptual report. (3) A *global* response decrease throughout visual cortex, be expressed throughout both hemispheres. We predict that this global response modulation will succeed both response components (1) and (2), as well as subjects* behavioral report. We will interpret the target-specific response decrease in visual cortex (1) as the neural basis of the subjective target disappearance, the motor build-up activity (2) as a correlate of subjects* subsequent perceptual decision, and the global response decrease in visual cortex (3) as a feedback signal re-entering early visual cortex. Specifically, based on the latencies relative to (2), we may conclude that this global modulation in visual cortex is triggered by the preceding perceptual decision.

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Secondary

Measure	Time frame
Not applicable.	—

Countries

Netherlands

Outcome results