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“Brain-predicted age” quantifies apparent brain age compared to normative neuroimaging trajectories. Advanced brain-predicted age has been well established in symptomatic Alzheimer disease (AD), but is underexplored in preclinical AD. Prior brain-predicted age studies have typically used structural MRI, but resting-state functional connectivity (FC) remains underexplored. Our model predicted age from FC in 391 cognitively normal, amyloid-negative controls (ages 18–89). We applied the trained model to 145 amyloid-negative, 151 preclinical AD, and 156 symptomatic AD participants to test group differences. The model accurately predicted age in the training set. FC-predicted brain age gaps (FC-BAG) were significantly older in symptomatic AD and significantly younger in preclinical AD compared to controls. There was minimal correspondence between networks predictive of age and AD. Elevated FC-BAG may reflect network disruption during symptomatic AD. Reduced FC-BAG in preclinical AD was opposite to the expected direction, and may reflect a biphasic response to preclinical AD pathology or may be driven by inconsistency between age-related vs. AD-related networks. Overall, FC-predicted brain age may be a sensitive AD biomarker.

Importance: More than 4 million Medicare beneficiaries have enrolled in dual-eligible Special Needs Plans (D-SNPs), and coordination-only D-SNPs are common. Little is known about the impact of coordination-only D-SNPs on Medicaid-covered services and spending, including long-term services and supports, which are financed primarily by Medicaid., Objective: To evaluate changes in Medicaid fee-for-service (FFS) spending before and after new enrollment in coordination-only D-SNPs vs new enrollment in non-D-SNP Medicare Advantage (MA) plans among community-living beneficiaries enrolled in both Medicare and North Carolina Medicaid., Design, Setting, and Participants: This cohort study applied a new user, active comparator design to control for selection into MA and inverse probability of treatment weighting to improve the comparability between groups. The cohort included community-living dual-eligible Medicare and Medicaid beneficiaries in North Carolina with 365 days of Medicare FFS enrollment prior to new enrollment in D-SNP (treatment) or other MA plan (active comparator). Linked 100% Medicare and North Carolina Medicaid claims data (2014-2017) provided payments across both payers prior to MA enrollment; after MA enrollment, payments for Medicaid-funded services and supplemental Medicaid payments for Medicare-funded services were observed. Data were analyzed from August 2023 to November 2024., Exposure: New D-SNP enrollment., Main Outcomes and Measures: Outcomes included annualized 1-year Medicaid FFS spending overall and by claim type, including inpatient, outpatient, carrier, home health, personal care services, and behavioral health services., Results: Among 8869 participants in the D-SNP cohort, 4762 (53.7%) were younger than 65 years, 5833 (65.8%), were female, and 975 (11.0%) resided in rural areas. After inverse probability of treatment weighting, characteristics were similar among the comparison MA cohort of 4389 participants (4706 [53.2%] aged <65 years; 5739 [64.9%] female; 971 [11.0%] rural). There were no significant differences in Medicaid FFS spending per person-year (PPY) at baseline or differential change in the year following new enrollment (mean marginal effect, -$387 [95% CI, -$1274 to $501) between groups. There were significant differences between groups in the change in spending on long-term services and supports, with maintained spending on community-based personal care services following new enrollment in D-SNPs compared with reductions for other MA, resulting in a relative increase of $343 (95% CI, $147 to $539)., Conclusions and Relevance: This cohort study found that coordination-only D-SNPs was associated with maintained North Carolina Medicaid FFS spending levels for long-term services and supports compared with other MA plans, despite limited integration requirements. However, to reduce or delay nursing home transitions, higher levels of integration may be necessary.

Objective: The authors aimed to examine racial-ethnic differences in filled psychotropic prescriptions among a pediatric Medicaid population., Methods: This retrospective cohort study included patients ages 0-21 with at least one North Carolina Medicaid claim from October 1, 2017, through September 30, 2018 (N=983,886). The primary outcome was a filled psychotropic prescription. Separate multivariable modified Poisson regression models generated adjusted risk ratios (ARRs) and 95% confidence intervals (CIs), adjusted for patient demographic characteristics., Results: Black and Hispanic patients were significantly less likely to receive any filled psychotropic prescription (ARR=0.61, 95% CI=0.60-0.62; ARR=0.29, 95% CI=0.28-0.29, respectively) compared with White and non-Hispanic patients. Furthermore, Black and Hispanic patients were less likely to receive filled prescriptions in the four included drug classes compared with White and non-Hispanic patients., Conclusions: Future studies should focus on understanding the factors contributing to racial and ethnic differences among pediatric patients receiving filled psychotropic prescriptions.

Objective: In adulthood, depressive mood is often comorbid with ADHD, but its role in ADHD-inattentiveness and especially relations with mind wandering remains to be elucidated. This study investigated the effects of laboratory-induced dysphoric mood on task-unrelated mind wandering and its consequences on cognitive task performance in college students with high (n = 46) or low (n = 44) ADHD-Inattention symptomatology and Hyperactivity/Impulsivity symptoms in the normal range., Methods: These non-clinical high/low ADHD-Inattention symptom groups underwent negative or positive mood induction after which mind wandering frequency was measured in a sustained attention (SART), and a reading task. Effects of ruminative response style and working memory capacity on mind wandering frequency were also investigated., Results: Significantly higher frequencies of self -reported mind wandering in daily life, in the SART and reading task were reported in the ADHD-Inattention symptom group, with detrimental effects on text comprehension in the reading task. Induced dysphoric mood did specifically enhance the frequency of mind wandering in the ADHD-Inattention symptom group only during the SART, and was related to their higher self-reported intrusive ruminative response styles. Working memory capacity did not differ between high/low attention groups and did not influence any of the reported effects., Conclusions: These combined results suggest that in a non-clinical sample with high ADHD-inattention symptoms, dysphoric mood and a ruminative response style seem to be more important determinants of dysfunctional mind wandering than a failure in working memory capacity/executive control, and perhaps need other ways of remediation, like cognitive behavioral therapy or mindfulness training.

Mind-wandering is the focus of extensive investigation, yet until recently there has been no validated scale to directly measure trait levels of task-unrelated thought. Scales commonly used to assess mind-wandering lack face validity, measuring related constructs such as daydreaming or behavioral errors. Here we report four studies validating a Mind-Wandering Questionnaire (MWQ) across college, high school, and middle school samples. The 5-item scale showed high internal consistency, as well as convergent validity with existing measures of mind-wandering and related constructs. Trait levels of mind-wandering, as measured by the MWQ, were correlated with task-unrelated thought measured by thought sampling during a test of reading comprehension. In both middle school and high school samples, mind-wandering during testing was associated with worse reading comprehension. By contrast, elevated trait levels of mind-wandering predicted worse mood, less life-satisfaction, greater stress, and lower self-esteem. By extending the use of thought sampling to measure mind-wandering among adolescents, our findings also validate the use of this methodology with younger populations. Both the MWQ and thought sampling indicate that mind-wandering is a pervasive-and problematic-influence on the performance and well-being of adolescents.

The negative effects of mind-wandering on performance and mood have been widely documented. In a recent well-cited study, Killingsworth and Gilbert (2010) conducted a large experience sampling study revealing that all off-task episodes, regardless of content, have equal to or lower happiness ratings, than on-task episodes. We present data from a similarly implemented experience sampling study with additional mind-wandering content categories. Our results largely conform to those of the Killingsworth and Gilbert (2010) study, with mind-wandering generally being associated with a more negative mood. However, subsequent analyses reveal situations in which a more positive mood is reported after being off-task. Specifically when off-task episodes are rated for interest, the high interest episodes are associated with an increase in positive mood compared to all on-task episodes. These findings both identify a situation in which mind-wandering may have positive effects on mood, and suggest the possible benefits of encouraging individuals to shift their off-task musings to the topics they find most engaging.

Although consciousness can be brought to bear on both perceptual and internally generated information, little is known about how these different cognitive modes are coordinated. Here we show that between-participant variance in thoughts unrelated to the task being performed (known as task unrelated thought, TUT) is associated with longer response times (RT) when target presentation occurs during periods when baseline Pupil Diameter (PD) is increased. As behavioral interference due to high baseline PD can reflect increased tonic activity in the norepinephrine system (NE), these results might implicate high tonic NE activity in the facilitation of TUTs. Based on these findings, it is hypothesised that high tonic mode NE leads to a generalised de-amplification of task relevant information that prioritses internally generated thought and insulates it from the potentially disruptive events taking place in the external environment.

Accumulating evidence suggests that the brain can efficiently process both external and internal information. The processing of internal information is a distinct "offline" cognitive mode that requires not only spontaneously generated mental activity; it has also been hypothesized to require a decoupling of attention from perception in order to separate competing streams of internal and external information. This process of decoupling is potentially adaptive because it could prevent unimportant external events from disrupting an internal train of thought. Here, we use measurements of pupil diameter (PD) to provide concrete evidence for the role of decoupling during spontaneous cognitive activity. First, during periods conducive to offline thought but not during periods of task focus, PD exhibited spontaneous activity decoupled from task events. Second, periods requiring external task focus were characterized by large task evoked changes in PD; in contrast, encoding failures were preceded by episodes of high spontaneous baseline PD activity. Finally, high spontaneous PD activity also occurred prior to only the slowest 20% of correct responses, suggesting high baseline PD indexes a distinct mode of cognitive functioning. Together, these data are consistent with the decoupling hypothesis, which suggests that the capacity for spontaneous cognitive activity depends upon minimizing disruptions from the external world.

The role of the intraparietal sulcus (IPS) in the representation of numerical magnitude is well established. Recently, there has also been speculation that the IPS is involved in the representation of ordinal information as well. These claims, however, overlook the fact that all neuroimaging paradigms in which participants make judgments about either magnitude and/or order result in a behavioral distance effect (i.e., the comparison is easier when the stimuli span a greater distance). This leaves open two possibilities: It may be that activation of the IPS is due to the mechanism that yields distance effects, or it may be that the IPS is involved in the representation of information about both magnitude and order. The current study used fMRI to compare a magnitude task in which participants show distance effects to an order-judgment task that yields reverse-distance effects. The results reveal activation of the IPS for both the magnitude and order tasks that is based on participants' strategies as opposed to the actual distance between the numbers. This leads to the conclusion that the IPS represents a mental number line, and that accessing this line can lead to distance effects when participants compare magnitudes and to reverse-distance effects when participants check for order.