Cognition Part 1 Flashcards
Cognition:
Attention Memory Executive Functions
Part I: Attention and
Memory
What is attention?
Attention: Characteristics
Definition
- Ability to utilize and direct one’s focus in order to receive and process information from one’s environment
- Classifications and definitions highly varied in literature
Classifications of Consciousness
- Alertness: Generalized readiness
- Selective or Directed Attention: Specific stimuli over irrelevant stimuli
- Awareness: Highest processing level
What is sustained attention?
Attention: Theoretical Concepts
Sustained Attention (Continuum)
- Concentration, Vigilance, Selective Attention, Non-Distractibility
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Definition
- Ability to direct attention toward a specific stimulus for an extended period of time
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Examples
- Sustained (boring material)
- Non-Distractibility (boring material in Starbucks, don’t let people around you distract you, ignoring outside stimuli)
- Vigilance (courtside at a game, in heightened state of attention bc of a lot of action, anticipate action)
What is shifting attention?
Shifting Attention (aka divided attention)
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Definition
- Ability to focus on one event then disengage and focus on new event and subsequently re-engage in previous event
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Example
- Locking door, answer phone, start one thing and completely forget what you were doing, Cooking.
What are the neural substrates for attention?
Attention: Neural Substrates
Foundation Systems
- Brainstem
- ARAS (Ascending Reticular Activating System) and basic alertness
- Thalamus and Limbic Connections
- Sensory processing and big role in attention
- Neurotransmitters
- Dopamine and norepinephrine
- Right Hemisphere
- Widespread connections to many brain areas
What are alerting functions?
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Alerting Functions
- Definition: Ability to focus in anticipation of events (at stoplight)
- Neural Substrates: Thalamus, Frontal and Parietal regions; Norepinephrine
- Dysfunction: Decreased ability to maintain alertness or slowed responses; Missing critical cues from environment
What are orienting functions?
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Orienting Functions
- Definition: Ability to choose one source of information to process among an array of stimuli (attend to conversation in restaurant)
- Neural Substrates: Superior Parietal Lobe, Temporal/Parietal Lobe junction, Frontal Eye Fields; Cholinergic System
- Dysfunction: Inability to selectively attend during competing stimuli or distractions
What is executive control of attention?
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Executive Control of Attention
- Definition: Ability to process multiple stimuli or highly complex stimuli at the same time (busy clinic)
- Neural Substrates: Anterior Cingulate Cortex (ACC))decision making, values), Lateral Prefrontal Cortex (LPFC); Dopamine
- Dysfunction: Inability to process multi-step or complex tasks or can only handle one step at a time
What are the hierachical processing levels?
Cortical Processing of Attention
Hierarchical Processing Levels
- Primary Somatosensory, Visual and Auditory Cortex
- Primary Motor Cortex
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Secondary Association Cortex (Unimodal Association Areas)
- Somatosensory, Visual and Auditory Association Cortex
- Motor Association Cortex: Supplementary and Premotor Cortex
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Tertiary Association Cortex (Heteromodal Association Areas)
- Posterior Multi-modal Association Cortex (MAC) in Parietal, Occipital and Temporal Lobes
- Anterior Multi-modal Association Cortex (AMAC) in Frontal Lobe
Explain the hemisphere dominance and why we only have left neglect.
Right Hemisphere Dominant for Attention
- Right Hemisphere attends to LEFT and RIGHT sides of hemispaces or environment
- Left Hemisphere attends to RIGHT side of hemispaces or environment
Dysfunction [SEE DRAWING]
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Right Hemisphere Lesion
- Common LEFT neglect syndromes (Examples)
- Left Hemisphere Lesion
- Rare RIGHT neglect syndromes due to Right Hemisphere attends to BOTH sides
Explain the role of the frontal and parietal association cortex’s.
Frontal and Parietal Association Cortex
- Frontal Cortex critical for attentional processing
- Parietal Cortex serves as alerting or “heads up” role for Frontal Cortex Strong reciprocal connections between Frontal and Parietal Cortex especially for processing multi-modal stimuli
- Superior Longitudinal Fasciculus/Arcuate Fasciculus
- Prefrontal Cortex/Dorsolateral Prefrontal Cortex/ Anterior Cingulate Cortex and Inferior/Superior Parietal Cortex
- PMAC and AMAC
Explain the role of the PPC and Frontal Premotor areas.
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Posterior Parietal Cortex (PPC) and Frontal Cortex critical for sensorimotor transformations (frontal lobe has strong role over sensory and motor outputs, coordination)
- Planning, decision-making, forward state estimation, and relative-coordinate representations
- Intended goal of movement, trajectory of movement, higher cortical function, and coordinate multiple body parts
- Frontal Premotor areas code for visual targets with eye- limb coordination or visually guided reaching
- Visual functions of smooth pursuits and saccades are also represented in Parietal Cortex
- PPC critical for motor planning and decision-making involving a temporal sequence (timing)
Explain coordination between lobes in relation to attention.
Cortical Processing of Attention
- Topographical representations in frontal and parietal areas related to motor planning or goal- directed actions
- Coordination among parietal areas, frontal eye fields (frontal lobe) directing visual attention and saccades, parietal functions related to spatial and visual spatial awareness
- Coordination among systems leads to memory storage of goal-directed actions (no such thing as muscle memory- this is where its stored) Also the basal ganglia is where automatic, stererogenic actions)
Explain the significance of the prefrontal cortex.
Prefrontal Cortex –(sustained attention)
- AMAC aka Frontal Heteromodal Association Cortex
- Key: Coordination of information from PMAC (sensory info)
- Key: Directed or Sustained Attention via Frontal Eye Fields (FEF)
- Role in initiation of eye movements (Saccades) to target of interest
- Initiation of motor control on contralateral side
- Reduction in distractibility
What is the relationship with the ACC and Limbic structures?
Anterior Cingulate Cortex (ACC) and Limbic Pathways
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ACC
- Key role in motivation needed for attending
- Error detection
- Assigning “value” to events
- Assigned value to events for decision-making
- Based on rewards and punishments
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Limbic Structures
- Key role in motivation needed for attending
- Stimuli of interest driven by emotions
- Example…