VC: Neuroanatomy Flashcards
Why is EEG useful in investigating the anterior cingulate cortex?
It is a cheap way to uncover the neural correlates if error and conflict detection.
What is error-related negativity?
A response-synchronised ERP related to error processing.
When does ERN occur?
About 100ms after response onset (mistake).
Where does the negative peak occur in ERN?
Fronto-central electrode sires.
What does the effect of the speed-accuracy trade off on ERN show?
That ERN amplitude is modulated by the degree to which accuracy is important to the subject.
How does ERN amplitude relate to response force on Flanker task trials?
There is reduced force when ERN is activated.
How does ERN amplitude relate to error correction on Flanker task trials?
Participants are more likely to immediately press the correct key after pressing the wrong one when ERN activated, in an attempt to correct their response.
How does ERN amplitude relate to post-error slowing on Flanker task trials?
PES increases with ERN.
How is degree of conflict qualitatively defined in conflict monitoring theory?
The simultaneous activation of incompatible representations, connected by inhibitory links.
Give 3 key factors about conflict, according to CMT.
It increases with absolute activation of competing representations, is maximal when competing activations are equal and increases with number of competing representations.
What Flanker task results suggest there are 2 anatomically and functionally different systems for error detection and conflict monitoring?
ERN spiked for error vs correct trials, but stayed the same for compatible and incompatible trials, and fMRI showed 2 different areas of activation.
In conclusions from the Flanker study, what brain area seems responsible for error detection?
ACC.
In conclusions from the Flanker study, what brain area seems responsible for conflict monitoring?
Pre-SMA.
Give 3 pieces of evidence suggesting that error and conflict processing may use the same brain area.
Participant difference are huge across the two tasks and almost the whole frontal brain is activated across participants, stroop tasks show activation for both in similar areas, and schizophrenic people show deficits for both in similar areas.
Give 3 deficits schizophrenic people show in error and conflict processing.
Reduced ACC activity, no post-conflict adjustments and no post-error adjustments.
Briefly describe the feedback loop that may help explain how control is adjusted.
The ACC detects averse or negatively reinforcing events, and the LPFC makes control adjustments (biasing behaviour away from tasks and strategies with high control demand).
How do the results of a stroop task show that the size of an error signal predicts control adjustments?
ACC activity on an incongruent trial predicts adjustment on the next trial, ACC activity on a trial predicts PFC activity on the next trial and ACC activity increases LPFC inhibition of irrelevant stimuli.
In a modified stroop task, what results regarding the DLPFC suggest there are separate instruction and response mechanisms?
The left LDPFC was selectively activated during during the preparatory period (more for colour naming).
In a modified stroop task, what results regarding the ACC suggest there are separate instruction and response mechanisms?
Selectively activated during the response period (more for incongruent than congruent colour naming trials).
What does the evidence from a reward-based decision making task suggest about the pMFC?
It’s increased activity in response to a decrease or absence of an expected reward shows that it is reacting to rewards.
What idea and evidence may join the 2 key theories about error and conflicts together?
People try to avoid cognitively demanding tasks, shown in the card experiment with many or few task repetitions, where people often chose the low demand set.
