Chapter 9: Attention And Awareness Flashcards
Awareness
Active thinking about or concentrating on some source of stimulation
Attention
Selection of some source of sensory stimulation for increased cognitive processing
Dichotic Listening
Listening to one message in left ear and different message in right ear
- attention affects recall- can recall what is paid attention to, but not the ear that wasn’t attended to
- low-level sensory changes in ignored ear are noticed, but changes related to meaning aren’t
Selective Attention
Attention to some things and not to others
- activity focusing on specific sensory system
Filter theory of attention
Suggests all sensory information is registered as physical signals, but attention selects only some of those signals to be interpreted for meaning with the rest being filtered out
*filter out meaning for low salience sensory info
—sensory stimuli form desired input channel and other sensory stimuli—> (sensory mechanisms)— desired info and other info—> (attentional filter based on physical features of signals)—desired info—> (limited-capacity system for higher-level processing, including evaluation of meaning)—desired info—> memory
Cocktail Party Phenomenon
Originally refers to auditory sense, selective attention occurs with other senses (notably vision)
Attenuation Model of Attention
Attenuators looks out for meaning in what we experience
- gets rid of filter
Inattentional Blindness
Failure to perceive a fully visible, but unattended visual object
- miss things because we’re not paying attention
Attentional Blink
Unawareness of stimuli in attended location of stimuli occur when we are processing something else
Ex. RSVP
Rapid Serial Visual Presentation (RSVP)
An experimental procedure in which visual stimuli such as letter or photos are presented very rapidly, one after the other, at fixation
Change Blindness
Inability to quickly detect changes in complex scenes
Selective Attention and Limits of Awareness
- looking at something is not the same as seeing it, just as letting the sound of a conversation into your ears isn’t the same as hearing it
- you have to pay attention to be aware of and fully understand what your eyes are pointed at or what you ears take in
Attention to Locations
Overt attention
Covert attention
Attentional Cuing
*eye movement isn’t needed to redirect attention
Overt Attention
Selectively attending to some info by moving one’s eyes
Covert Attention
Selectively attending to some info without moving one’s eyes
Attentional Cuing
- Provides a cue about the location and timing of an upcoming stimulus
- Examines how the spatial location of a person’s attention affects the speed with which the person can become aware of something and respond to it
- eyes stay at fixation point
Attention affects neural responses in […]
Attention affects neural responses in V4
- Shifting attention: directing attention to particular spatial location without moving your eyes, causes corresponding changes in brain activity
Attention and Brain Activity
- can be directed to different spatial locations, enhancing awareness of and other cognitive responses to stimuli that appear in those locations
- affects the responses of sensory neurons with receptive fields in attended locations
- selects which of many competing stimuli will be represented for further cognitive operations
Attention to Features
Visual search research
Feature search
Conjunction search
Visual Search Research
Searching for specific target in a scene containing one, a few, or many objects
Feature search
Searching a display for an item that differs in just one feature from all other items in the display
Conjunction search
Searching a display for an item that differs from all other items in display by having a particular combination of two
- changes in multiple domains
Attention and Activity in Area MT
Activity in area MT increases when the attention is on the motion of objects
Object-Based Attention
Attentional selection of an entire object when attention is directed to part of object
- when we attend to an object we seem to be able to attend to it a whole
Distributed Representation
Representation that is distributed across multiple brain regions
Feature Integration Theory
Theory that some perception takes place stages
- resolves binding problem by proposing that attention is directed to one object at a time
Sensory stimulus (visual scene)—> preattentive stage (stimulus features sensed but not bound together)—> focused attention stage (attention binds object features together, creating an accurate mental representation of the scene)
*Put together in V1 and beyond
Why attention is selective
Selective attention has evolved to deal with constraints on perception that result from how the brain represents objects
- Binding problem
- Competition for neural representation
- Biased competition theory
Binding problem
- problem faced by visual system of perceiving which visual features belong to same object
- how organisms manage to determine which visual attributes fo together to correctly perceive objects in the environment
- if not solved correctly, the illusory conjunctions result
- features of objects are processed separately in different areas of brain
Illusory conjunctions
Erroneously perceiving objects that consist of features present in sene, but in wrong combination
*Balent’s syndrome- parietal lobe damage that can cause binding problem
Competition for neural representation
Object with features that match the neuron’s preferences drives the neurons to produce a strong response, while objects with features that do not match the neuron’s preferences evoke only a weak response
Biased competition theory
- brain resolves the competition for neural representation by selectively attending to one object and representing the feature of just that object
- can put together one object at a time
- attention biases the competition so that only the features of the attended object are represented, as if only the attended object were present
What happens when a person looks into a cluttered visual scene?
- every neuron in the visual system that has an RF large enough to include two or more objects or object features must resolve the competition for representation by attending to one object and ignoring the rest
Attentional Control
- Top-down processing
- Bottom-up theories
Top- down processing
Deliberately paying attention to something in order to get info needed to achieve goals
Aka. Voluntary attentional control
Bottom-up theories
Involuntary, unavoidable capture of attention by salient perceptual stimulus
Aka. stimulus-driven attentional control
Attentional Capture by Abrupt Onsets
If someone is looking intently somewhere, it’s likely that what they’re looking at is interesting or important
Gaze Cues and Autism
Neurologically typical individuals: brain can distinguish congruent and incongruent gaze
Autistic individuals: reduced sensitivity to where others are looking
Value- Driven Attentional Control
Capture of attention by learned reward value of stimulus
- reward value: things that are meaningful to us
- recent work indicates that attentional control is not always top-down or bottom-up
- it can be influences by stimulus features that are not related to current goals or physical salience
- makes us more likely to notice objects important to us, even when we’re not looking for them
Brain Areas Involved in Attentional Control
Frontal eye field (FEF) and posterior parietal control (PPC)
Unilateral Visual Neglect
Condition in which a person has difficulty attending to stimuli in one half of visual field (almost always left half), as result of damage to contralateral PPC
- PPC damage can occur due to stroke
- can’t pay attention, but can still see it
Attentional Control and Activity in the Posterior Parietal Cortex (PPC)
- Fixation Task
- Saccade Task
- stimulus was cue for monkey to make eye movement - Reach Task
- cue to make hand movement to stimulus while maintaining gaze an fixation point - Peripheral Attention Task
- cue to wait for stimulus to dim without changing direction of gaze
Attentional Control: studies of brain activity in humans using fMRI
- Showed that human PPC and FEF are important sources of attentional control
- FEF: control eye movement and role in controlling shifts of attention without eye movement - Confirmed PPC is important component of brain’s ability to control spatial attention
- Provided strong evidence that PPC and FEF are important sources of signals that control visual attention
Awareness and the Neural Correlates of Consciousness: Chalmers
- Suggested the easy problems of consciousness: objectively observable data; third- person data
- Posed the hard problem of consciousness: how subjective experiences arise from neural activity’s first-person data
- Advocated for search for neural correlates of consciousness (NCCs); correspondence between neural activity and conscious awareness
- Idea is to tackle consciousness with minimal reliance on first-person data and max reliance on third-person data
Perceptual Bistability
Phenomenon in which unchanging visual stimulus leads to repeated alternation between two different perceptual experiences
Binocular Rivalry
A phenomenon in which two different images presented to the two eyes result in perceptual bistability
Perceptual bistability and binocular rivalry
- perception reverses spontaneously despite the fact that the visual information remains unchanged
- both bottom-up theories propose that neural fatigue underlies the perceptual switching
- top-down theories propose that the viewer must know the figure is bistable and the possible interpretation before perceptual switches are possible (and involve intentionality)
PPC can direct attention to […]
PPC can direct attention to visual object
- Activity as early as area V1 appears to reflect conscious visual experiences
Blindsight and vision
Phenomenon provides evidence for the existence of the unconscious as a contributor to human behavior
Blindsight Experiment
- area V1 necessary for awareness, but other aspects of vision don’t require functional area V1
- Based on signals that pass from retina to superior colliculus, through thalamus and into visual cortex - Can’t support conscious vision, but provides sufficient visual info to support visually guided actions and categorization of emotionally charged objects
Multitasking in real life
- Involves task switching
- rapid shifting of attention from one task to another and back again - Suggests that the very act of switching attention from one task to another significantly increases the time spent on each task
True or False: The impairment in driving performance while talking on a cell phone is similar to the impairment in driving performance while legally intoxicated
True
