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Attention refers to the process by which we __ our __. Also, working memory seems to require __ __.
- focus
- awareness
- conscious access
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What are the 3 functions of attentional processes?
- Orienting function toward environment
- Partial control of the content of consciousness
- Maintaining alertness
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What is the Global Workspace model and who proposed it?
- Baars
- Based on observation that human brain comprises several specialised systems (for perception, attention, language etc) each of which carries out its task at a level that does not reach the threshold of consciousness.
- Consciousness becomes possible when these various subsystems pool certain results of their operations in a single, global workspace. When expressed in this forum, they become accessible to brain as a whole, and therefore conscious.
- Serves as a site for information exchange. Other subsystems can take advantage of this available info too.
- akin to a form of momentary working memory
- accounts for various evidence for interaction between conscious and unconscious processes observed in various phenomena
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Who gave a neuroanatomical account of this global workspace model? What was it?
- Dehaene et al
- Global neuronal workspace hypothesis (GNW) - perceptual, attention, memory, value, and motor areas interconnect to form higher-level unified space where info is shared
- Pyramidal neurons of the cerebral cortex - with their long axons that can connect areas of cortex that are distant from one another
- Esp in thick layers II/III - which is particularly dense in PFC
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In contrast to Baars's model, what did Dehaene's model do?
- Baars's model simply distinguished one conscious state from multiple unconscious ones, but Dehaene's model distinguishes between 3 possible states of activation:
- 1. subliminal processing: not enough bottom-up activation to trigger wide scale activation of network
- 2. Preconscious state: enough activation to access consciousness, but is temporarily kept from doing so by lack of top-down attention
- 3. Conscious state: preconscious stimulus receives enough attention to cross consciousness threshold
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What is the function of consciousness that makes it different from attention?
- It does not select information but summarises all relevant info
- making this compact summary accessible to other stages of cognition and brain areas
- (eg. planning stages, detecting anomalies, decision, language, rational thought)
- This integrative aspect is emphasised by the Integrated Information Theory of consciousness (Tononi, 2004)
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So, the integrated, connectionist model of consciousness is emphasised in the integrated information theory of consciousness. Just briefly explain this modl.
A mathematical model intended to describe and quantify the nature of consciousness. It is based on the idea that the consciousness of a system may be measured by the amount of integrated information.
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Think of selective attention as an __, consciousness as a ___.
- attention as analyser
- consciousness as a synthesiser
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Give examples of percepts and behaviours that can be found without consciousness. One group for those that doesn't require top-down attention either and one group requiring top-down attention.
- No conscious/no attention: formation of afterimages, rapid vision (<120ms)
- No conscious/attention: priming, adaptation, visual search, processing of objects, blindsight
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How about those that require consciousness but not top-down attention and those that require both?
- Conscious/no attention: pop out, iconic memory
- Conscious/attention: working memory, detection of unfamiliar stimuli, full reportability
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What is a good example of how awareness and attention can be dissociated (have one without the other)?
- Blindsight (De Gelder et al)
- Blindsight patients (patient TN with bilateral lesion of striate cortex - the 'where' stream through superior colliculus intact, but not 'what' stream from striate cortex - that is why it is unconscious.)
- Can navigate a room with obstacles and avoid them without consciously realising if they are really there or what they are.
- Attention exist without awareness - exogenous
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What can inattentional blindness tell us about attention and awareness?
- Simons & Chabris (1999) famous experiment
- Many observers failed to see a gorilla-suited man walking past scene if they were focusing on how many passes were being made in that scene.
- Attention to the scene, but selectively, and thus without awareness of a major change.
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What are the important points about modularity and the mind?
- The brain seems to organised in a modular fashion
- However, conscious part of the brain/mind seems to be non-modular
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