Cognitive Neuroscience

frontal -parietal control

Higher order cognitive operations that are subserved by the prefrontal cortex

programming, regulating, monitoring, attention/inhibition, task managemetn, contextual coding, planning, monitoring

• Choose goal
• plan-subgoals
• execute-sequencing
• monitor progress
• interweaving planning and executing
• flexibility

• The ability to plan for a goal and take concrete stepts to reach goal
• The ability to be flexible and deal with novel situations
• The ability to prioritize tasks and to switch between them
• The ability to assess or evaluate the efficacy of actions

• Norman and Shallice
• 1. Fully automatic processing controlled by SCHEMATA
• 2. Passive processing controlled by Contention Scheduling
• 3. Supervisory Attentional System (SAS)

• knowledge-restaurant- picking up the phone.
• schema need to be developed before they are automatic

• action-sequence: coming to class and taking notes
• -Gear changing when driving is performed "automatically" (without conscious awareness)
• -When routines clash, relative importance is used to determine which to perform (contention scheduling) (left foot on brake or clutch)

• override action sequence via voluntary control
• -Driving in England - inhibit look right, activate look left
• SAS overides habitual actions

dancer, choice of response, novelty

Habitual actions become automatic (overactive CS)

SAS does not inhibit a habit (underactive CS)

perceptual system ->trigger database ->contention scheduling (passive, prevents simultaneous activation of multiple schema) SAS overlay (flexible behavior, learning novel stimuli, overcoming habits, error correction etc) -> effector system

• Lateral prefrontal cortex
• ventromedial prefrontal cortex

• Medial frontal gyrus
• Superior FG
• Inferior FG

damage to left frontal cortex

• seizure left him with lack of motivation
• frontal astrocytoma
• passive detachment

• but lack ability to function in every day life
• (example with errands)

• sensory processing of stimuli
• understanding task instructions
• selecting a response
• executing a response
• understanding feedback
• planning next response
• mainintaing correct rule
• manipulating response based on new rule
• switching strategy based on a new rule

• 1. tendency to focus on one stimulus dimension at the expense of others
• 2. inability to ignore a dimension hat was reinforced previously

• robust activator and engager in executive control
• but so broad - is maintaining a rule separate from retaining a rule?
• doesn't fractionate aspects of control into difference subprocesses

• Condition A: card task alone, no distraction
• Condition B: task while hearing high and low pitched sounds, keeping count of sounds

• Hippocampal activity greater for condition A than B
• Striatal activity greater for Condition B than A
• Memory for cards better in condition A
• flexibility to extrapolate categories better in A

executive attention is INDIVISIBLE. you are actually rapidly switching between tasks!

activate pathways, inactivate pathways, switch

remember the number for trail 1 and trial 2, then remember the letter for trial 3 and trial 4

yes, switch task trial takes longer for normal subjects, and even longer for frontal lobe pts

RT on switch-RT on no-switch trials

Show oddball target and get the P3b response in both normal and pre-frontal region damage pts.

Show oddball and task-irrelevant (novel) stimuli, get the P3a to novel, task-irrelevant stimuli, don't get this for pts wtih prefrontal damage.

• Parietal regions important for response to targets- P3b for targets,
• Frontal regions important for response to novel stimuli P3a for novel stimuli