Final Flashcards
Attentional Bottleneck
- Attention acts as a filter, blocking unimportant stimuli and focusing cognitive resources on only the most important events
- protects the brain from being overwhelmed by the world
Shadowing tasks
-Task where participant is asked to focus attention to one of the two stimuli and repeat the material presented in attended ear
Divided attention task
- a task in which the Participant is asked to focus attention on two or more stimuli simultaneously
- confirm that attention is a limited resource.
Early selection of attention
Unattended information is filtered out right away, at the level of initial sensory input.
(I.e. Shadowing experiments)
-before semantic and even basic perceptual analysis
Late selection of attention
- After semantic analysis has occurred
- important but unattended stimuli may undergo substantial unconscious processing up to level of semantic meaning and awareness before capturing attention (I.e. Hearing your name at a crowded bar)
Neural evidence for early selection
Larger N1 is observed in ERP for the attended ear of a dichroic listening task (where stimulus is input in both ears)
When late selection occurs
When perceptual load in attended channel is low, semantic processing In the unattended channel is possible
Feature search
Basic features like—motion, color and basic form—pop out.
-Can be processed before attention comes on line and before you process meaning of situation
-early attention
Conjunction search
Search for item based on two or more features (I.e. Size and color)
Requires attention because these different features are processed by different regions in the brain
Feature integration theory (FIT)
Theory that attention is the “glue” that binds features together so that objects can be perceived as a unit and selected for further processing
Illusory conjunctions
Mislicatiins of features can occur when spatial attention is impaired
-distracted/ poor visual conditions
2 ways to move attention
Covertly
Overtly
Covertly
Without repositioning the sensory organs
-uses Pulvinar (thalamus)
Overtly
Reposition the sensory organ
-uses superior colliculus (midbrain)
2 ways to guide attention
Endogenous
Exogenous
Endogenous
Directed voluntarily by internal goals of perceived
- top down
- symbolic cueing tasks (use arrows/ meaningful symbols to guide attentions)
- slower onset but can be sustained
Exogenous
Drawn reflexively by information in the environment (involuntary)
- bottom up
- peripheral cueing tasks (use sensory stimulus to grab attention)
- faster onset but diminishes quickly
Valid cue (Correct guidance= benefit)
Benefits reaction time ONLY if presented Briefly Before the target
Inhibition of Return
If there is a delay between cue and target, reaction time is slowed compared to invalid cue’s reaction time
Invalid cues (Incorrect guidance= cost)
Cue is not in the same place as the target
-slower to respond than neutral cue
Neural activity
Attention boosts neural activity Associated with the features or area of space your attending to
Dosal frontoparietal system
Endogenous–voluntary control
- cognitive control
- too down
Intraparietal sukcus (IPS)
Involved in voluntary top-down control of attention
Ventral temporoparietal system
Novelty detection
-Right side is dominant in attentional orienting
Temporoparietal junction (TPJ)
Role in shifting attention to a new location after target onset
Asymmetric attention control
Right hemisphere: takes care of both sides
Left hemisphere: only takes care of right side
Hemispatial neglect
Neglect to the side of space opposite of Lesion
-most commonly follows Right superior parietal damage—neglect left side of space
Balint’s syndrome
-bilateral damage to parietal lobe
- difficulty directing attention overtly–eye movements
- optic ataxia (cannot appropriately reach for things)
- simultagnosia
Simultagnosia
- restriction of attention
- can attend to only one object at at time
Simultaneous extinction
Find out
Executive functions
Carried out by prefrontal cortex
Taxonomy of executive functions
Establish and modify rules:
- initiate new rules
- inhibit inappropriate rules
- shift among rules
- relate rules
Contextual Control
-monitor whether rules are working
Working memory
-space for maintaining rules and info needed to execute rules
Dorsolateral PFC
Important for dealing with novel or ambiguous COGNITIVE decisions
- develops new, inhibits old and tests rules
- modifies behavior based on feedback
Maintain mental effort toward pursuit of goals even when distracted
Damage to dlPFC
-Perseveration—get stuck: unable to inhibit old rules
- no long term goals
- can cause apathy or abulia
Dysexecutive syndrome
Collection of deficits associated with dl PFC damage
-can be tested with Wisconsin card sorting test
Apathy
Lack of interest or concern
Ventromedial/orbitofrontal
Important for dealing with novel or ambiguous SOCIAL and EMOTIONAL decisions
- evaluate meaning and appropriateness of possible responses in social context
- infer mental states of others
- integrate physiological info (gut feelings) into decision making
Damage to vmPFC
- inappropriate affect, aggression, inability to control sexual impulses
- impaired insight into self and others
Disinhibition Syndrome
Collection of deficits associated with vmPFC
-cannot judge self conscious emotions like guilt, jealousy, embarrassment
Severest case= sociopathy
Sociopathy
Engage in aggressive acts with little remorse and little care for others
Confabulation
- damage to vmPFC
- retrieve false information, but go with it and try to create an autobiographical narrative
- “honest lying”
Abulia
Lack of ability to act decisively or make decisions
- act slowly and are distracted easily
- difficulty maintaining attention
Frontopolar
Portion of lateral PFC important for RELATING rules to create higher order, abstract models of the world (I.e. What if)
- plan of larger goals with Su goals
- complex relational and integrative processes
- holding info seeking goals with long term rewards, not short term
Environmental Dependency Syndrome
Damage to anterior (polar) and medial regions
-behaviors initiated by external environment rather than internal goals
- lack insight of causes and consequences of actions
- stuck in here and now, not good at longer abstract goals
Imitation
Copy what they see
-physical, vocal, etc
Utilization behavior
Lack of top down influence, so when they see an object, they use it
-relies on external stimuli to trigger behavior
Raven’s Matrices IQ test
Requires integrating multiple rules
-like sudoku
-3x3 or more complex table with different pictures following different rules
Person is asked to complete last box
Tower of London
Requires multiple Su goals
Dorsomedial and Anterior Cingulate Cortex (ACC)
Monitor and allocate resources for control of behavior
- detect mismatch between internal top-down expected/ desired outcome and bottom-up external info
- communicates with lateral PFC to indicate how much executive control is needed to keep behavior on track
The stroop task
-read words (that spell a color) and are in a specific color
- word and color may be incongruent
- incongruency activates ACC and relates to how much you slow down and adjust (monitoring)
Ventral ACC
Emotional
-More stimulate in ppl with depression
Damage to ACC
Does not impair performance on Stroop task
-ACC is correlated (no causation) to task
ERN
Error related negativity
(ERP is negative)
- follows mistaken action:
1. Motor mov’t that a participant realized is incorrect
2. Feedback indicating action did not result in desired outcome
Amplitude of potential is positively related to engagement of control processes
Working memory
- temporarily maintains and manipulates information not currently available to the senses
- necessary for achieving short term behavioral objectives
From perception to memory
Encode (take in from senses) –store — retrieve
- bottom up = transforming experience into memory
- top-down = using past memories to shape experience
Models of working memory (WM)
Baddeley’s Model
Cowan’s Model
Baddeley’s Models
Storage of WM is separate from storage of Long term memory (LTM)
Separate buffers for different types of info (i.e. Episodic, visuospatial, etc.)
Cowan’s Model
No separate WM storage
WM is a spotlight of info in LTM
-central executive can manipulate a small subset of activated representations at a time
Manipulation of WM
- dorsolateral anterior PFC
- compare and group info
Maintenance of WM
Initial retrieval of info
Ventral posterior PFC
-left vlPFC: verbal info
-right vlPFC: nonverbal/spatial info
Primacy effect
Superior performance seen in a a memory task for tens at the start of a list
-attributed to LTM
Recency effect
The superior performance seen in a memory task for items at the end of the list
-attributed to short term memory…aka WM
Amnesia disrupts Serial Position Effect
- intact recency effect Bc WM is normal
- impaired primacy effect Bc amnesia affects transfer of info to LTM, but leaves WM intact
Types of Long term Memory
Declarative
Nondeclarative
Declarative
Things you know that you can tell others
- past we can represent using symbolic format (I.e. Language)
- tested with EXPLICIT tests: ask them to think back and remember
- involves some level of CONSCIOUS awareness in process of retrieval
Nondeclarative (procedural)
Things you know that you can show by doing (I.e. Riding a bike)
- memory inferred by a change in performance due to previous experience (incremental learning)—->faster and more accurate
- tested with IMPLICIT tests
- does NOT involve CONSCIOUS recollection of the past events that led to the change
2 types of declarative
Episodic
Semantic
Episodic memories
Include specific info about the context (time and place) in which info was learned –like encoding episode
-examples: autobiographical memories, personal events
-uses hippocampus and prefrontal
Semantic
Memory associated with recalling facts
-example: word meanings, non-personal, general facts and events
-doesn’t involve prefrontal
Before consolidation
Need hippocampus AND cortical ares
Post consolidation
Cortical areas ONLY
Process of episode
- Engage in perceptual processing (v1)
- Hippocampus/ medial temporal lobe (MTL) bind together the cortical memory traces at encoding and reconstruct the memory at retrieval
- Using few retrieval cues, hippocampus can reactivate the whole memory trace
Memory retrieval
Construct memories from parts we can retrieve
false memories
Memories that are partly or wholly inaccurate but are accepted as real by person remembering it
Korsakoff’s Syndrome
Result of alcoholism–and poor diet
- amnesia and confabulation
- can see some recovery of function
3 types of Nondeclarative
Skill/Habit
Conditioning
Priming
Skill/Habits
Gradual improvement in performance with practice
Uses: Basal Ganglia and Cerebellum
Classical conditioning
Learning associations between events
Uses: cerebellum
Priming
Improvement in processing a stimulus as a result of having seen it before
2 types of Priming
Perceptual
Conceptual