Task 5 Flashcards
What can be sad about the V1 in regards to visual consciousness?
It is most likely not the location of the visual NCC. Activity here is modulated by attention and not so much the conscious percept of a stimulus
The fact that attention modulates V1 activity more than awareness has been shown by a famous 2x2 study by Koch et al. Describe this design.
Visibility of the target was manipulated by flash suppression.
Location of attention was manipulated by asking the participant to focus on a task.
What result of Koch’s study lead to the finding of the research?
When patients were paying attention to detecting the target, they had increased blood oxygenation in V1, independently of whether they actually detected the target or not.
If BOLD signal in V1 is not moderated by perceiving a stimulus, by what is it affected?
Shifting attention
What is another valuable insight derived from the fact that shifting attention moderates activity in V1?
It means, that top-down attention affects even lower levels of vision
What are two cognitive processes that moderate the effect of change blindness paradigms?
Attention and working memory
According to Lamme’s Theory, what comes first: The decision whether something is attended vs unattended, or conscious vs unconscious?
Conscious vs unconscious
Describe the process of stimuli becoming consciously reportable according to Lamme’s Theory.
First, inputs are sorted into conscious and unconscious stimuli. From the conscious ones, we can then attend or not attend some. Only the attended ones reach the state of being aware/consciously reportable.
Describe an experiment that supports Lamme’s view of the relationship of conscious and awareness.
Change blindness paradigm -> If the change between picture 1 and 2 is hinted at between the presentation of the pictures, participants can indicate the change. This shows that when normally, they wouldn’t have been able to report the change, they were still conscious of it, but didn’t attend to the change. The cueing of the change brings the attention of the participant to the location, which makes the change consciously reportable.
How can saliency of a stimulus be described neurodevelopmentally?
Saliency reflects how long-term memory has shaped and modified sensory processing.
In search of the NCC, what theory does Lamme support?
Feedforward Sweep & Recurrent Processing
What is recurrent processing?
When the activity going from low to high in the perceptual hierarchy reaches a certain point, there is interaction between this region and other areas in the brain including ones further back downstream.
When does RP start to happen?
~100ms
How can RP theory explain why visual masking works?
The stimulus disappears to quickly, for RP to occur, thus the stimulus does not reach awareness.
Explain the principle of Access Awareness
When perceptual information is processed in higher order cortical areas and is embedded in the full cognitive context of needs, goals, desires, etc. Here, the image of what we are aware of is “less blurred” and physiologically, there are widespread recurrent interactions. Due to a high level of competition between receptive fields, we can’t have access awareness of unlimited capacity.
