Statistical regularities in distractor location trigger suppression of high-probability distractor locations during visual search. The degree to which such suppression reflects generalizable, persistent changes in a spatial priority map has not been examined. We demonstrate that suppression of high-probability distractor locations persists after location probabilities are equalized and likely reflects a genuine reshaping of the priority map rather than more transient effects of selection history. Statistically learned suppression generalizes across contexts within a task during learning but does not generalize between task paradigms using unrelated stimuli in identical spatial locations. These findings suggest that stimulus features do play a role in learned spatial suppression, potentially gating the weights applied to a spatial priority map. However, the binding of location to context during learning is not automatic, in contrast to the previously reported interaction of location-based statistical learning and stimulus features. Public Significance StatementWith practice, people can learn to ignore locations in space that are likely to contain distracting information. We show that such learning has a persistent influence on attention that generalizes across context during learning but fails to generalize to new contexts not experienced during learning.

Attention is biased toward stimuli that have been associated with aversive outcomes in the past. This bias has previously been interpreted as reflecting automatic orienting toward threat signals. However, in many prior studies, either the threatening stimulus provided valuable predictive information, signaling the possibility of an otherwise unavoidable punishment and thereby allowing participants to brace themselves, or the aversive event could be avoided with fast and accurate task performance. Under these conditions, monitoring for threat could be viewed as an adaptive strategy. In the present study, fixating a color stimulus immediately resulted in a shock on some trials, providing a direct incentive not to look at the stimulus. Nevertheless, this contingency resulted in participants fixating the shock-associated stimulus more frequently than a neutral distractor matched for physical salience. Our findings demonstrate that threatening stimuli are automatically attended even when attending such stimuli is actually responsible for triggering the aversive event, providing compelling evidence for automaticity.

Attention prioritizes stimuli previously associated with reward or punishment. The present study examined whether this attentional bias, widely considered to be involuntary and automatic, could be suppressed with sufficient motivation. Participants performed visual search for a shape-defined target. One color-singleton distractor predicted the possibility of receiving a reward and another an electric shock, with each outcome occurring infrequently. Participants were informed that the likelihood to earn a reward or avert punishment depended on fast and accurate performance, thus providing strong motivation to resist distraction by rewardand shock-related stimuli. Results revealed a reduction in the magnitude of attentional capture by reward-and threat-associated distractors, relative to neutral distractors, that persisted into extinction. In a second experiment, we replicated the suppression of value-modulated attentional capture in the absence of the shock condition, thus confirming that the suppression did not result from the presence of threat. Finally, in a third experiment, we replicated the typical pattern of attentional capture by reward cues using a more conventional procedure in which the motivation to suppress valent stimuli was low (the likelihood to be rewarded was high and not contingent on fast performance). This study demonstrates that signals for reward and threat can be actively suppressed with sufficient motivation.

Purpose: The neurometabolic timecourse of healthy aging is not well-established, in part due to diversity of quantification methodology. In this study, a large structured cross-sectional cohort of male and female subjects throughout adulthood was recruited to investigate neurometabolic changes as a function of age, using consensus-recommended magnetic resonance spectroscopy quantification methods. Methods: 102 healthy volunteers, with approximately equal numbers of male and female participants in each decade of age from the 20s, 30s, 40s, 50s, and 60s, were recruited with IRB approval. MR spectroscopic data were acquired on a 3T MRI scanner. Metabolite spectra were acquired using PRESS localization (TE = 30 ms; 96 transients) in the centrum semiovale (CSO) and posterior cingulate cortex (PCC). Water-suppressed spectra were modeled using the Osprey algorithm, employing a basis set of 18 simulated metabolite basis functions and a cohort-mean measured macromolecular spectrum. Pearson correlations were conducted to assess relationships between metabolite concentrations and age for each voxel; paired t-tests were run to determine whether metabolite concentrations differed between the PCC and CSO. Results: Two datasets were excluded (1 ethanol; 1 unacceptably large lipid signal). Statistically significant age-by-metabolite correlations were seen for tCr (R2=0.36; p<0.001), tCho (R2=0.11; p<0.001), sI (R2=0.11; p=0.004), and mI (R2=0.10; p<0.001) in the CSO, and tCr (R2=0.15; p<0.001), tCho (R2=0.11; p<0.001), and GABA (R2=0.11; p=0.003) in the PCC. No significant correlations were seen between tNAA, NAA, GSH, Glx or Glu and age in either region (all p>0.25). Levels of sI were significantly higher in the PCC in female subjects (p<0.001) than in male subjects. There was a significant positive correlation between linewidth and age. Conclusion: The results indicated age correlations for tCho, tCr, sI, and mI in CSO and for tCr, tCho and GABA in PCC, while no age-related changes were found for NAA, tNAA, GSH, Glu or Glx. Our results provide a normative foundation for future work investigating the neurometabolic time course of healthy aging using MRS.