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what is consciousness?
how do I know when someone is conscious? – is it enough that information is taken in
(sensation), experienced (perceived), and then a change in behavior occurs to decide that "X" is conscious?
– Maybe this is the definition of awareness instead.
What is Consciousness?
the waking states (i.e. perception, emotion, thinking), but also altered states of consciousness, such as sleep, dreaming, drug induced states, hypnosis and meditation?
what is consciousness?
Weiten defines consciousness as "...the awareness of internal and external stimuli."
but bythis he means 1. awareness of stimuli in the external environment
2. awareness of stimuli in the internal environment
3. awareness of "self" as having these experiences
4. awareness of the thoughts you have about these three other things
what is consciousness?
but in some ways, this is like putting the problem inside the brain [the "self" is a homunculus located somewhere inside the brain?]
also, how do we come to understand what it means to "have an experience"?
what is consciousness?
we can understand the processes of information input, storage, retrieval, etc but still the "experience" is not explained.
what is the opposite of consciousness? unconsciousness?– perhaps a continuum from alert and active to
asleep to coma?
what is consciousness?
Consciousness: our awareness of the world and of ourselves.
However, when we fall into an Altered State of Consciousness: a shift from our awareness in the normal waking state.
Research
Research on states of consciousness investigates two very different response variables:
Physiological Activity, that accompanies the conscious state.
Subjective Report, of what is experienced during the state.
Research Lines that led to study of consciousness
1. Research with primespriming words leads to measurable greater
recognitionelevates level of consciousness for the word
2. Neurocognitive studies:
sleep/wake = conscious/unconscious?
Brain injury = impaired ability to consciously recall = neurological basis
Explicit vs. Implicit Memory
Explicit - consious recall of info Implicit - memory that is measured
through a performance change related to some previous experience (ex, priming)
Research with Primes
Prime:
College
Is it a real word?
University
Prime:
Jelly
Is it a real word?
University
Priming works without subject’s awareness.
Subliminal Priming– Lexical decision task– Bread --> XXXX--> Sandwich– Truck--> XXXX--> Sandwich
Conclusions on Subliminal Priming Under specific conditions, subliminal
priming happens If stimulus is presented below sensory
threshold, subliminal priming does not occur
Neurocognitive Studies
Sleep: EEG– can see change from state of
consciousness to unconsciousness and then return to consciousness.
– Can tie levels of consiousness to phsyiological measures of brain
Neurocognitive Studies
Amnesia - discovery of 2 types of memory, some involving conscious recall and others not.
Factors:
1. Limited Capacity
2. Novelty Metaphor - consciousness functions to direct attention toward adaptation to novel and significant events.
3. The spotlight - metaphor for consciousness-how is the focus selected?
-once it is selected, what happens to the info?
4. Theater Metaphor
Theories of Consciousness
1. Schacter’s Model of Dissociable Interactions and Conscious Experience (DICE)
2. Baar’s Global Workspace Theory
Functions of Consciousness
1. Define and Set Context– define a stimulus and remove ambiguities from
perception
2. Adaptation and Learning– more novelty = more conscious involvment for
successful learning and adaptation
3. Prioritizing and Access Control– prioritizing more imp. Info, making it more
conscious more often
Functions of Consciousness
4. Recruitment and Control of Mental and Physical Actions– conscious goals recruit subgoals and motor
systems to organize and carry out actions
5. Decision Making and Executive Function– minimizes indecision by directing our efforts
toward choice points
6. Error Detection and Editing
Functions of Consciousness
7. Reflective and Self-Monitoring Function
8. Optimizing the Trade-off between Organization and Flexibility– consciousness plays role in unpredictable
situations; unconsciousness governs predictable situations
What is Attention? (back to Chapter 4)
ability to focus on a task
• ability to concentrate
refers to the allocation of processing resources (Anderson, 1995)
Theories of Selective Attention
Selective attention theories suggest that we have a tendency to orient ourselves toward only one part of the environment with the exclusion of other parts. – There is abundant evidence which supports that
selective attention is governed by arousal level. – The most persistent question has been whether
the shifts in attention that accompany changes in the arousal level are automatic, or deliberate.
Selective Attention
Although it's clear that we do filter out a great number of stimuli, it's not at all clear how we do it, nor what information we note unconsciously. – In an attempt to find out psychologists
have frequently used dichotic listening experiments (i.e. two different messages presented separately to each ear), roughly along the lines of the situation at a party.
Broadbent
Broadbent (1957) developed the filter model to explain the proposition that a bottleneck occurs before pattern recognition, and that attention determines what information reaches the pattern recognition stage. – This model asserts that the selective filter
allows information to come in from only one channel at a time, into working memory.
Demonstration
Read the bold print.
Somewhere Among hidden the in most the spectacular Rocky Mountains cognitive near
abilities Central City is Colorado the an ability old to miner select hid one a message box from of
another. gold. We Although do several this hundred by people focusing have our looked attention for on it, certain they cues have such not as found
type it style.
What do you remember from the regular print text? What does this tell you about selective attention?
Bottleneck theories or filter theories (Broadbent, 1958) bottleneck is a mechanism that limits
the amount of information to be attended to
what gets through? what is selected and when?
“bottleneck” in filter theory
Broadbent's Model
Properties: 1.Early selection
2.Selection (filtering) is based on physical properties of the stimulus (e.g., pitch, loudness..)
3.Attention directed to info that passes the filter or to physically salient info that leads to shift in attention.
4.Only one input channel processed at a time.
5.It takes time to shift attention.
dichotic listening task
used to illustrate Broadbent's filter model. – participant puts on set of headphones, requested to
listen to only one ear, and report that info. • The information presented to the participant is different
between the two ears, and therefore fits the filter model perfectly.
– Participants lack awareness of the unattended ear's content, or even language.
• Those who do know that the other ear's information varies can only report whether it was a human voice, and whether it was a male's or female's voice.
Shadowing task
An extension on Broadbent's Dichotic listening task is the Shadowing task, which requires participants to repeat the attended ear's information out loud. – Shadowing a message provides proof that
the participant is following instructions, and is attending to the correct ear. During a shadowing task, subjects are completely unaware of the unattended ear's message.
Problems with the model:
"cocktail party" phenomenon– The questioning of Broadbent's selection
filter's location arises, since the participant is able to follow the switch between ears in continuing a message.
Treisman
Treisman proposed a model which consists of two components, each relying on the other to function properly, named the attenuation model.
In Treisman's attenuation model, the selective filter distinguishes between two messages on the basis of their physical characteristics, such as location, intensity and pitch. The ‘dictionary' in Treisman's model allows for selection between messages on the basis of content. – Certain information requires a very low threshold
inactivating awareness of a stimulus, such as our name in the cocktail party example.
Treisman's Attenuation Model
Properties:1.Early selection
2.Selection (attenuation) is based on physical properties of the stimulus (e.g., pitch, loudness, etc...).
3.Attention is directed toward information that reaches a threshold of recognition.
4.Several inputs can be processed at a time.
Broadbent and Treisman's models proposed that the selection filter in attention occurs prior to selection, or pattern recognition stage. – Later models by Deutsch and Deutsch (1963), and
Norman (1968), merged growing information regarding memory and the selection process of attention. These more recent models claimed that selection occurs after the pattern recognition stage. In these models attention is equivalent to the selection stage.
SummaryEarly Selection vs. Attenuation vs. Late Selection
Broadbent proposed that physical characteristics of messages are used to select one message for further processing and all others are lost
Treisman proposed that physical characteristics are used to select one message for full processing and other messages are given partial processing
Deutsch & Deutsch (1963) proposed that all messages get through, but that only one response can be made (late selection)
•
SummaryEarly Selection vs. Attenuation vs. Late Selection
Treisman & Geffen (1967) tests between attenuation and late selection -- guess who wins?!
dichotic listening + detect target words in either channel (tap upon detection)
detection much worse in unattended channel, supporting attenuation...if late selection, detection should be no problem since all info is getting through