Cognitive Neuroscience

individuals w executive dysfunction have psychological inertia- its difficult for them to initiate a path of action, and then difficult to stop once they are on that path

tendency to repeatedly perform the same behavioral response even when it is no longer appropriate (WCST)

• person's behavior is drven by environmental cues
• respond to cues in an automatic stimulus-response manner that has been conditioned by learning rather than by an internally generated goal

the supervisory attention system not able to overide behavior (frontal lobe damage)

• when you have to respond or withhold an action/response (go-no-go)
• inferior prefrontal cortex tied to inhibition, involved in overriding prepotent responses

Inferior prefrontal regions

not well- won't be able to inhibit

• Evaluation of the appropriatentess of one's actions and plans
• Error-related negativity

• tied to a person knowing they made an error
• use EMG- when EMG shows movement, timelock to EEG and get larger voltage deflection when they get it wrong

• Emphasis on speed: not much of an ERN
• Emphasis on accuracy: large ERN

the ERN

• 100-150 milliseconds after a response
• is greater when accuracy is emphasized
• is greater, the larger the error
• may index an emotional, not just a cognitive reaction

Anterior Cingulate Cortex

• fine at recognition of which items appeared in the sequence
• poor at determining which item appeared more recently

maybe sequencing is difficult bc experimenter controlled so let the patient control sequencing with self-ordered pointing task

difficulties occur even when frontal lobe damage pts determine the sequence themselves

• Norman & Sallice:
• 2 systems for control of behavior
• contention scheduling controls routine behavior
• SAS controls non-routine behaviors

• Shallice:
• behavior of frontal patients reflects the functioning of contention scheduling in the absence of the supervisory attention

sensory-short term - long term

• 100-150 msec
• few to several seconds
• minutes to lifetime

sensory input->sensory memory (unattended info quickly lost)->attention->Working short term memory (maintenance rehearsal or info is lost if not rehearsed)->encoding ->Long-term memory (retrieval back to STM, or some info lost over time)

rows of letters flashed, tone indicates which row to remember, subject reports cued line

• name as many items as you can remember
• name only items that are cued

• can remember more when line is cued.
• flash had to be long enough
• used iconic memory (visual) to have attention and then extract out info to report
• attention in sensory memory allows it to move to working memory

fleeting store of information

report was almost perfect.

• as delay of signal increases, performance level decreases.
• this tells us how fleeting sensory memory is

• Iconic ("picture")
• Lasts 500 ms to 1 sec
• Forms automatically without attention of interpretation
• unconscious to the person
• separate sensory-memory store for each sensory system

• Vision (Iconic Memory : Visual info)
• Hearing (Echoic Memory- Auditory info)
• Touch
• Smell
• Taste

• To retain all the sensory input long enough for:
• analysis by unconscious mental processes
• transfer to STM/Working memory via the "Attention" process

This moment in time (short term)

memory storehouse (long term)

• Active contents of consciousness
• Active nodes in LTM
• Fast access to contents
• Limited capacity

• Not currently in consciousness
• Inactive until cued
• slower access
• unliminted capacity