pattern of conflict modulation during one correct response is 489 orthogonal to the pattern during another correct response
i.e. it is not a 'general boosting' effect -> only on average the activity of neurons can still increase, but it is all about upregulating the relevant neurons for this correct response
higher when Ericksen conflict was present (Figure 2A)
Yeah, in single neurons you can show the detection of general conflict this way, and it was not partitionable into different responses...
with Ericksen conflict than it was for trials without Ericksen
what about simon?
This does mean: Conflict increases representation shifting response toward correct action!
AUC
This axis has more predictive power when there is conflict than when there is no conflict (task is already so easy that the information is not needed, or at least a lot less?)
amplification hypothesis, conversely, does not predict a unified conflict 341 detection axis in the population. Instead, it makes a prediction that is exactly contrary to 342 the epiphenomenal view: that conflict should shift population activity along task-variable 343 coding dimensions, but in the opposite direction. That is, conflict is predicted to amplify 344 task-relevant neural responses
conflict means more control will be exterted. Heavier representation of whatever info it is that dACC encodes that 'pushes' for the correct action. This function of dACC would be in line with the context layer!?
At the population level, then, the epiphenomenon hypothesis330 predicts that conflict should decrease the amount of information about the correct response 331 and shift neuronal population activity down along the axis in firing rate space that encodes 332 this response
Because less % of neurons 'fighting' for the correct response are active, at least in total.
Neurons that were tuned for a specific correct response were 298 often tuned to prefer the same Simon/Ericksen distractor response
DLPFC is tuned to action-outcomes? -> in single neurons!
neurons did not encode the distractor response
So on trials with a unique distractor response, that action-outcome was not represented at all? It's interesting but then where does the actual conflict take place?
significant 270 proportion of neurons were selective for the correct response
So desired action-outcome is represented. I think that was already known about dACC.
Furthermore, the population of cells whose responses were significantly 244 affected by Eriksen conflict was almost entirely non-overlapping with the population 245 significantly affected by Simon conflict (specifically, only one cell was significantly 246 modulated by both)
Really separate representations for different aspects of the current task-set?
additive model was a better fit to the data than other, more 205 flexible models
So separate statistical significance testing shows effect for Eriksen, not for Simon, but regression model shows through model comparison that it's best to ascribe to them the same effect...
(n=15/145) neurons had significantly different firing rates between Simon and no-196 (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. The copyright holder for this preprintthis version posted March 15, 2020. . https://doi.org/10.1101/2020.03.14.991745doi: bioRxiv preprint
No significant main effect but more single cells had a significant effect...? -> also directionality is not all positive, some positive some negative
A small number of individual 187 neurons also had different activity levels on Eriksen conflict and no conflict trials (8.2%, 188 n=12/145 neurons, within-cell t-test)
Note the difference between 'averaged over all neurons' (first report) or 'within one specific neuron' (this report)
activity was higher on Ericksen conflict 185 trials than on no conflict trials
for Eriksen flankers there is a main effect of conflict (vs no-conflict). Simon was not statistically significant. Was it mainly a power issue?
4917.0 (1) 5826.5 (1)*
Additive model is the winner in single cell firing rates -> coding simply for the notion of conflict? cf. the population coding from dimensionality reduction!
Subtracting this expectation from the observed pattern 723 of activity left the residual activity that could not be explained by the linear co-activation 724 of task and distractor conditions
So this is what to analyze: If this still covaries with conflict in some way it means we go beyond epiphenomenal?