Cognitive Flashcards
Who is Wilhelm Wundt and what did he do?
The father of psychology - set up first psychology lab and used introspection to study thought
Decomposed thought into simpler components - emotion, perception, sensation
Structuralism
First attempt to study thought scientifically
What is structuralism?
Studying the structure of thought - decomposing thoughts into simpler components
What approach did William James coin?
Functionalism
How do mental processes operate?
What are the characteristics of mental processes?
How do we control behaviour?
What approach did Watson and Skinner coin?
Behaviourism - react to limits of introspection
- Focuses on observable causes of behaviour - associations between stimuli and responses
- Applying psychology
What approach did Koffka and Kohler coin?
The Gestalt approach (reaction to structuralism)
- Human thought seen as whole - impossible to break into smaller bits without losing the essence of the thought
- Emphasises organised units in perception and behaviour that cannot be reduced to component parts
What approach did Freud, Adler and Jung coin?
Psychodynamic approach (reaction to behaviourism)
- Focus on unconcious motivations as causes of behaviour
What does the Information Processing Approach in early cognitive psychology propose?
Rekindled scientific interest in unobservable mental processes like attention and signal detection
(Indirect measure of cognitive processes)
New paradigm developed - people as active information processors, and cognition conceptualised as a series of information processing stages
What is cognitive neuroscience?
Integrating models and theories from the IP approach with advances in understanding brain systems
(Are cognitive theories biologically plausible?)
What did functionalism develop from and how did James implement it?
Developed from pragmatism in philosophy - to find the meaning of an idea, you have to look at its consequences.
This led James towards emphasis on cause and effect, prediction and control, observation of environment and behaviour.
Laid groundwork for behaviourism
What is cognitive psychology?
Understanding the mental processes that allow us to make sense of our environment, and help us decide how to react to the environment and implement those decisions
Generate descriptions of how these mental processes function - typically a flow chart
What is functionalism?
Draws a distinction between
- Structure of a mental state (neural activity), and
- Function of a mental state (the consequences of the mental state - e.g. behaviours or new mental states
Cognitive psychology is about developing a functional explanation of mental processes
What is type identity theory?
A mental state is equivalent to a specific pattern of neural events
What is token identity theory?
A mental state maps onto a variety of different neural events
What is the two body/ two brains problem? (Searle, 1994)
Two people can have the same thought (‘mental state’) but must necessarily have different patterns of neural events (because all brains are different).
E.g. if I ask everyone “what is 4 x 4” the answer 16 pops into everyone’s heads. Thus, we all have the same mental state but different neural states.
If cognition is the processing of signals, how do psychologists measure cognition by investigating signal processing? (3 measures)
Redundancy - how much signal is needed to detect and identify a stimulus
Reaction time - how long does it take to detect or identify a stimulus
Capacity - how many signals can be processed simultaneously
What does measuring signal processing (redundancy, reaction time, capacity) allow psychologists to do?
Allows psychologists to operationalise and measure abstract concepts such as attention, memory, perception, planning, reasoning, motivation etc
- Measure cognition as how well signals are processed
What is the computational metaphor of the mind?
Input, processing, output
- Brains are like computer hardware, cognition (thought) is software (Searle, 1994)
- Sensory information transformed into internal representations which lead to actions
- Cognition refers to the processing of these internal representations
- Cognitive psychology is concerned with understanding the process, not the hardware
Assumption - mental software used for different processes is modular - programs can run independently of one another
What are Marr’s (1982) 3 Levels of Description?
1) Computational Theory level
2) Representation and algorithm level
3) Hardware level
(1 and 2 are of primary interest to cognitive psychologists)
What is computational theory level? (Marr’s (1982) 3 Levels of Description)
Asks:
- What is the function of cognition and what different cognitive functions there are
What is representation and algorithm level? (Marr’s (1982) 3 Levels of Description)
Asks:
How cognition works - how information is stored or internally represented and what operations algorithms are used to manipulate internal representations
What is hardware level?
Asks:
How the representations are instantiated in the real world
What is modularity? (Fodor, 1983)
Human cognition is organised into discrete mental modules, each of which fulfils a specific function
What are horizontal faculties? (Modules)
General competencies used across domains
e.g. LTM
What are vertical faculties?
Domain specific cognitive functions and processes
e.g. language production or object recognition
What is information encapsulation?
Modules do not need to interact with other modules to operate successfully
Does disruption to a module affect processing in other modules?
Not necessarily
e.g. damaging an object recognition module does not affect STM
What are characteristics of modules?
- Modules correspond to anatomically defined brain areas
- Modules are similar across humans
- Module processing is fast and obligatory (happens without conscious thought and cannot be suppressed)
What types of faculties (modules) does cognition involve?
Activation of horizontal and vertical faculties
e.g. naming a face might draw on a visual module, memory faculty and linguistic module
What are input systems? (modularity)
- Process incoming sensory information
- Transfer information to central processors
- Domain specific (only process a particular class of information)
Typically these are vertical faculties
What is a central processor? (modularity)
Makes decisions and plans actions (not modular)
What is an effector system? (Modularity)
These execute responses
What is dissociation?
A manipulation that affects one cognitive task but not a different task
e.g. Spatial memory - saccades disrupt this (eye movements)
Verbal memory - saccades do not disrupt - we know that verbal and spatial are different
What is a double dissociation?
Completing two tasks that must be controlled by different cognitive modules
e.g. After doing task that affects spatial but not verbal, also do task that affects verbal but not spatial
Spatial memory - articulative rehearsal has no effect
Verbal memory - articulative rehearsal disrupts this
Can conclude that they are separate modules
What is cognitive neuropsychology? What methods does it use?
Looks at what brain damage can tell us about normal cognition
- Reverse engineering cognition
- Localisation of functions less important
- Typically investigate single cases
Same idea as dissociations - lesions instead of interfering task
Single dissociation:
e.g. DF - cannot recognise objects, but can use them - shows ventral part of brain deals with object recognition
Double dissociation:
Patients with parietal cortex lesions - can recognise objects but cannot use them
What was discovered from patient HM? (Scoville and Milner, 1957)
Had neurosurgery to cure epilepsy
- Could not form new memories (severe anterograde amnesia)
- Short term memory OK, could learn new skills
- Showed that LTM, STM and procedural memory must be different systems
- Revolutionised understanding of how memory functions
What are limitations of cognitive neuropsychology?
Rarely know normal performance - how good a person was at a task before injury
Does not account for functional reorganisation of cognition - patients could adopt compensatory strategies
Can’t say anything about time-course of information processing
Damage is rarely focal (e.g. stroke affects large brain area)
What is attention?
Filters out irrelevant stimuli
What did William James conceive attention to be?
The taking possession of the mind of one out of several simultaneously possible objects or trains of thought
Focalisation, concentration of conciousness
What is focusing attention closely tied to?
Concious perceptual experiences
How much information can be carried through the optic nerve?
Up to 100 megabits (MB) per second
What parts of attention are studied?
Input - selection of relevant sensory information - what cognitive mechanisms?
Central process - resource for switching between different tasks, concentration, active processing - once we have processed, how do we decide what action to take?
Is attention a module?
Better to conceive of it as an ‘Attentional Network’ of several different modules and processes that interact to guide behaviour
What is Posner and Peterson’s (1990; 2012) Three Component Model of the attention system?
1) Alerting: a system that regulates arousal level to maintain optimal vigilance (central process)
2) Orienting: prioritising relevant sensory signals (input module)
3) Executive: the conscious control of behaviour (central process)
How can components of the attention system be double dissociated?
Hemispatial neglect - deficit of attention to right brain and left body
- Orienting problems with no executive or alerting deficit
Alien hand syndrome - commissurotomy and frontal lobe injury - no control over a hand - failure of executive network
- Deficit of conscious control with no deficit of orienting or alerting
What is the ‘cocktail party’ effect? (Cherry, 1953)
How can people attend to one person while ignoring other conversations?
Ignoring speech from most people to listen to one person talking
What is the shadowing paradigm/ dichotic listening task? (Cherry)
Different word lists played to left and right ear
Participant must repeat words from one ear
- Participants cannot recall words presented to unattended ear - fail to detect language changes or backwards words
What does the dichotic listening task show about attentional orienting?
It acts like a filter that prevents information in the unattended channel being processed
What is Broadbent’s Filter Theory? (1958)
First information processing theory of attention
- Information about physical properties (e.g. tone, pitch, loudness) of stimuli are processed pre-attentively
- This information is used for channel selection: choosing which source of input to process
- Attention module filters out irrelevant info
- Attended information is processed and acted on
- Information in the unattended channel is lost
Sensory processing
- Channels 1 and 2
Input modules: Attention module
- Channel 1, channel 2 is stopped
Central process: Channel 1 continues through to semantic processing and working memory
How does ‘breakthrough’ from unattended ear challenge Broadbent’s filter theory? (Moray, 1959)
Not all unattended information is lost: “breakthrough” from unattended ear - when word in unattended ear makes sense in the context of the message in the attended ear
The persons’ name occurs in the unattended ear (e.g. Moray 1959)
What is attenuation theory? (Triesman & Geffen, 1967)
Filter limits the amount of stimulus information that can be processed
- Attended stimuli analysed in detail
Processing attenuated in unattended channel, but not extinguished
- Much less information available to identify the stimulus
Breakthrough occurs when
- Stimuli can be identified using limited information (e.g. a beep in spoken language)
- Stimuli is consistent with ongoing tasks
- Stimuli are very easily identified (e.g. own name)
Channel 1 and 2 are processed all the way through, but more attention is payed to channel 1 after they both pass through the attenuating filter and carry on to semantic processing and working memory
- Revision of Broadbent’s filter theory
What is the spotlight metaphor of attention?
Spotlight a filter that moves through space (Posner 1980)
Zoom-lens (Erikson & St. James 1986)
- Spotlight is flexible
- Wide focus, little detail
- Tightly focused, lots of detail
Generalising a filtering module from auditory to visual system
What is overt attention?
A movement of the eyes to fixate the location of interest
What is covert attention?
Orienting attention to a location that is not being fixated (no eye movement)
What is the spatial cueing task? (Posner, Snyder & Davidson, 1980)
Fixate the centre of the screen and a cue orients attention to one or other side
Participant must respond as quickly as possible to the appearance of the target
Usually 3 types of trial:
Valid: Target appears at cued location
Invalid: Target appears opposite cued location
Neutral: Cue does not indicate any location
Experiment 1:
Cue is valid on 80% of trials,
Experiment 2:
Cue valid on 50% of trials (no incentive to attend to cued location)
On experiment 1 people preferentially look at invalid cues on both central and peripheral cues
On experiment 2 people look more at invalid than valid for peripheral cue, equal looking for central arrow cue
- 80% valid - Shows that you can look at one thing and pay attention to something else
- 50% valid - if arrow is informative then people do not use it
- Peripheral cue - stronger response than central cue
What is the exogenous system for orienting spatial attention?
Orient to salient location - orienting of attention towards unexpected visual targets
Involuntary
Stimulus-driven
Fast (Max effect @ 150ms)
Transient
Inferior Parietal Lobe & ventral frontal regions (right)
Inhibitory after-effect
What is the endogenous system for orienting spatial attention?
Orient to task relevant location - orienting of attention towards visual targets
Voluntary
Goal-directed
Slow (Max effect after 300ms)
Sustained
Superior Parietal Lobule, FEF (bilateral)
Which attention theory is consistent with exogenous and endogenous attention?
Consistent with attenuating filter theory that prioritises information at the attended location
What is feature integration theory? (FIT)
Integrates attention into information processing model of perception
Paying attention - bind visual features together - this forms an object
Input modules e.g. colour, shape, location, texture
Visual representation
Attentional spotlight leads to:
Central processing - relates to memory (episodic, declarative, procedural)
Output modules
What is the binding problem? Who explored this?
Visual processing splits objects into component features
- Paying attention - bind visual features together - this forms an object
- Target identified by single unique feature - tends to pop out, does not matter how many distractions there are
- Conjunction - more difficult, affected by distractors
How does the visual system know which ones belong together?
Triesman & Gelade (1980) explored this using visual search tasks
What are visual search tasks? Triesman & Gelade (1980)
Find a target in a cluttered display
Set size (the number of items)
Target Type
Target Present (Pos)
Target Absent (Neg)
Disjunction (feature)
Conjunction
What are the two stages of processing of feature integration theory?
Preattentive, when objects defined by single, salient feature
Attentive, when features need to be combined
Attention acts like a ‘glue’ that binds features into objects
What are illusory conjuctions? (Triesman & Schmidt, 1982)
Participants identify numbers then identify shapes in briefly presented displays (200ms)
Participants incorrectly report letter/colour combinations that are not present
Paying attention to the peripheral would mean issues with binding the colour letter combinations in the middle
Triesman argues this shows attention needed to bind features into objects
What is the capacity of the attentional filter?
Filter capacity limited to ~3-4 items
What studies back up the capacity of the attentional filter?
Change blindness: which object changes?
One object changes after a black screen - hard to detect the change with six objects on screen - limited capacity filter
For 3 items, less of a change blindness effect
Multiple Object Tracking (Pylyshyn & Storm 1988)
Monitor specific objects moving - usually limited to three or four objects of a group
Participants can accurately (85% correct) track up to 5 objects
What number of locations can be attended to?
Some argue for multiple loci (up to~4) (Baldauf & Deubel 2010)
Different filters for different effector systems?
Other argue for a single, indivisible locus of attention (Jans, Peters & De Weerd., 2010)
What is early selection and who argued for this?
Early filter theories argue that attention module prevent the processing of irrelevant stimuli.
Broadbent, Cherry & Treisman argued for early selection
- Filtering occurs between perception and semantic processing
- Unattended receive limited or no semantic processing
What evidence is there for early selection?
Broadbent (1958) argued that unfiltered stimuli are not processed at all!
- Shadowing (Broadbent 1958):Very poor recall for information presented to unattended ear
- Selective looking (Neisser & Becklen 1975)
- Change blindness (Rensink et al. ,1997)
- Inattentional Blindness (Mack & Rock 1998)
What is the attenuated filter? (Triesman, 1964) How did this change early selection theory?
Irrelevant information can pass through filter if capacity not filled by relevant information
Depends on capcacity
What is the ball passing or hand slapping experiment?
Participant views video, has to count either how many ball passes or how many hand slaps
Ppt shown overlapping streams but only attend to one
Same thing happens but with an unexpected event
Attention is focused in such a way that unexpected event is not realised
How are ERP studies consistent with early selection?
Magnitude of change is measured
When attending to a stimulus and ignoring another one, the magnitude of ERP is smaller than when new stimulus is attended to
Shows it is an intentionally selective mechanism
What are practical consequences of attention producing signal enhancement in visual cortex?
Attention enhances spatial resolution (Yeshurun & Carrasco 1998)
Attended locations have higher perceived contrast (Carrasco, Ling & Reid 2004)
What neurophysiological evidence supports attention link with the visual cortex?
- Phosphene: An illusory visual experience triggered by stimulation of the visual cortex
- Attention modulates the responses of early visual areas such as V1, V2, V4 and V5
- Attention lowers phosphene thresholds in visual cortex
How does attention affect our perception of light and dark?
- Perceive difference between light and dark as greater when they pay attention to it
- Lower phosphene thresholds - more sensitive to changes
What did Deutsch and Deutsch (1963) propose?
That filtering occurred AFTER semantic processing
Selection based on which items are consistent with the observers’ goals
How do Flanker Interference Effects provide evidence for late selection?
Identify direction of central chevrons/arrows (L/R) when the surrounding arrows are either pointing the same way or a different way
Reaction times faster and fewer errors in congruent condition because of less interference
How does ‘Blindsight’ in patient PS provide evidence for late selection? (Halligan & Marshall, 1988)
PS has hemispatial neglect: inattention to left side of space
PS - lesions to right brain
She does not consciously perceive the flames when shown image of burning house (and reports the houses as identical)
But, when asked to pick one to live in she picked the non-burning house of 9/11 trials!
What have electrophysiological studies of auditory attention shown? (Hillyard et al., 1973)
Participants attend to one ear, ignore the other
Detect occasional probe stimuli in a stream of ‘standards’ (non-target sounds)
- Big spike in ERP associated with early processing in attended ear
- Also evidence for late processing - late perception (300ms after stimulus starts)
Suggests attention can modulate both early and late processing
