Because the outcome of the PLS analysis might vary with the valence of our materials, we conducted separate analyses for Negative and Neutral scenes. For Negative scenes, the first LV accounted for 76% and 79% of the covariance between intrusion control activations and behavioral measures of intrusion proportion and affect suppression within the frontoparietal retrieval suppression network and the MTL mask, respectively (p < 0.05). The first LV was significantly different from random noise as assessed by permutation testing (p < 0.05). For Neutral scenes, the first LV accounted for 73% and 68% of the covariance between behavioral measurements and the prefrontal retrieval suppression network and the MTL mask, respectively (p < 0.05). A second LV was not significant for either Negative or Neutral scenes.
B, Scatter plots observed in the proper MFG showing the relationship grabbed because of the PLS investigation between your upregulation (Invasion ? Non-Intrusion) and behavioural scores to have Bad and Basic moments
The presence of a critical LV one to makes up a massive portion of the covariance anywhere between intrusion-handle activations and you will all of the behavioral strategies reveals that certain voxels from inside the prefrontal cortex and you will MTL are linked to mnemonic and/otherwise affective control over unpleasant memories. They do not, although not, indicate how head activation sugar daddy Kansas City MO relates to those individuals actions. To accommodate a lot more clear interpretation of your own part of them voxels, we second computed “voxel salience” (the fresh voxels that every triggered our very own trick LV) and you can a brain score for each and every participant (select Material and techniques). A head get ways just how much certain participant conveys the fresh new multivariate spatial trend out-of relationship anywhere between intrusion manage activations and behavioral steps from mnemonic and affective manage captured because of the an LV.
Thus, correlations between notice scores and behavioral dimensions help to select the brand new guidelines while the fuel of relationships grabbed by the confirmed LV (which means that the newest corresponding voxel salience more one LV)
Critically, within the frontoparietal control network, we found that, for negative scenes, participants’ brain scores for the first LV correlated positively with their affect suppression scores (r = 0.60 p < 0.05, [0.35, 0.79] bootstrapped 95% CI) and negatively with intrusion proportion (r = ?0.79, p < 0.05, [?0.91, ?0.60] bootstrapped 95% CI; Fig. 5A). Importantly, this finding indicates that for those voxels having a positive salience, upregulation during Intrusions (vs Non-intrusions) negatively correlated with intrusion frequency (i.e., better mnemonic suppression), and additionally positively correlated with affect suppression score (i.e., better affective suppression) for Negative scenes (for an illustration of this pattern, see Fig. 5B). These patterns are inverted for voxels associated with a negative salience. Voxels within our retrieval suppression mask associated with a significantly positive salience (using a bootstrapping procedure; see Materials and Methods) were localized across the entire control network, including left and right MFG, dorsal portion of the anterior cingulate cortex, superior frontal medial gyrus, inferior frontal gyrus, insula, and inferior parietal cortex (Fig. 5A; Table 3). For Neutral scenes, participants’ brain scores for the first LV also correlated negatively with intrusion proportion (r = ?0.72, p < 0.05, [?0.87, ?0.54] bootstrapped 95% CI) but, in contrast to findings with negative scenes, showed no significant correlation with their affect suppression scores (r = ?0.16, [?0.54, 0.19] bootstrapped 95% CI; Fig. 5A).
Outcome of the PLS analysis for both Negative and Neutral scenes (conducted within the retrieval suppression network; see Materials and Methods) between intrusion-related upregulation (Intrusion ? Non-Intrusion) and behavioral measures (intrusion proportion and affect suppression score). A, Voxels showing a significant pattern of brain/behavior correlations as revealed by the first (significant) LV were identified using a BSR threshold higher/lower than 1.96/?1.96, respectively (i.e., p < 0.05). Correlations between participants' brain scores and behavioral measures for the first significant LV are also reported in A. Error bars indicate bootstrapped 95% CI. Brain scores reflect the contribution of each participant to a given LV. The correlation between brain scores and behaviors thus reveals the meaning of the LV. These findings reveal voxels whose upregulation is associated with reduced intrusion frequency for both Negative and Neutral scenes and also with increased affect suppression score only in the case of Negative scenes (reduced negative affect for suppressed images). BSR maps were rendered on the top of the PALS human surface using Caret software (Van Essen et al., 2001) (RRID:SCR_006260).