Faculty Bibliography

BACKGROUND:Attention-deficit/hyperactivity disorder (ADHD) symptomatology in childhood is associated with a high risk of suicide attempt later in life. However, symptom presentation in ADHD is heterogeneous, and little is known about how suicide risk varies according to different profiles of ADHD symptoms and sex. OBJECTIVE:The aim was to investigate the longitudinal associations between childhood profiles of ADHD symptoms (ie, hyperactivity-impulsivity and inattention) and youth suicide attempt in males and females, separately. METHODS:This population-based cohort study used data from three longitudinal cohorts: the Quebec Longitudinal Study of Child Development (QLSCD), the Quebec Longitudinal Study of Kindergarten Children (QLSKC) and the Quebec Newborn Twin Study (QNTS) for a total of 4399 participants (1490 from the QLSCD, 2134 from the QLSKC and 775 from the QNTS; 50% females) followed up from ages 6-23 years. Symptoms of hyperactivity-impulsivity and inattention were assessed by teachers five times from ages 6-12 years. Suicide attempt in adolescence and young adulthood (by age 23) was self-reported. Multitrajectory modelling was used to identify profiles of ADHD symptoms, and regression analysis was used to test their association with suicide attempt, adjusting for childhood socioeconomic and clinical characteristics. FINDINGS/RESULTS:We identified four ADHD symptom profiles with distinct associations with suicide attempt for males and females. Compared with those with persistently low symptoms, females with persistently high inattention and hyperactivity-impulsivity (OR: 2.54, CI 1.39 to 4.63) or high inattention and low hyperactivity-impulsivity (OR: 1.81, CI 1.21 to 2.70) were at higher risk of suicide attempt, while, among males, only those with decreasing hyperactivity-impulsivity and inattention over time (OR: 2.23, CI 1.20 to 4.13) were at higher risk of suicide attempt. CONCLUSIONS:Risk of suicide attempt in children with ADHD symptoms varies according to both symptom profile and sex, the highest risk being for females with high inattention symptoms (with or without hyperactivity), and males with decreasing symptoms. CLINICAL IMPLICATIONS/CONCLUSIONS:Taking into account differences in both sex and ADHD symptoms profile may be relevant to more accurately identify and manage suicide risk in individuals with high ADHD symptoms, though caution is needed when generalising our population-based findings to clinical populations.

Sharp wave-ripples (SPW-Rs) are critical to hippocampal function, and the same is true of gonadal steroids, but the interactions are unclear. We find that surgical removal of the gonads greatly reduces SPW rates in both sexes. Ripples are greatly reduced also. Testosterone treatment rescues SPW and ripple rates in males, and 17β-estradiol restores SPW rates in females. We also find that male SPW rates are higher than females but have less power. Furthermore, in intact females, SPW rates fluctuate with the stage of the ovarian cycle. These data demonstrate that hippocampal SPWs are significantly affected by gonadal removal, testosterone, and 17β-estradiol. In addition, there are sex differences. The data are consistent with past demonstrations that testosterone and 17β-estradiol play central roles in hippocampus and significantly expand the views of hormone action and SPW-Rs.

Preterm birth can significantly impact cognitive development, particularly executive functions (EF). This study investigated hot (with emotional/motivational aspects) and cool (purely neutral/cognitive) EF trajectories in preterm and full-term children, examining brain-behavior relationships. It included 3508 participants aged 9-10 years (mean age 10.0 years) at baseline from the Adolescent Brain and Cognitive Development (ABCD®) study, evenly split between preterm and full-term births (54.36 % males; 1.05 % Asian American, 10.69 % Black, 15.68 % Hispanic, 61.57 % White, 11.09 % other). Participants were followed for 4 years, completing MRI scans and a cool EF task at baseline and at the 2-year follow-up, as well as hot/cool and hot EF tasks at the 1- and 3-year follow-ups. Linear mixed models showed varying effects of preterm birth across the different EF tasks. Specifically, preterm children showed persistent cool EF deficits and a catch-up pattern for hot EF, while performance on the hot/cool task showed no association with preterm birth. Brain-behavior bivariate latent change score analyses identified distinct bidirectional relationships in specific regions, suggesting altered cognitive-brain maturation interactions in preterm children. These findings highlight the complex nature of EF development following preterm birth: while cool EF deficits persist, hot EF shows catch-up growth in preterm children during early adolescence. This emphasizes the need for tailored interventions and long-term follow-up in this population.

OBJECTIVE/UNASSIGNED:To examine the effects of Serdexmethylphenidate/dexmethylphenidate (SDX/d-MPH) on ADHD symptoms throughout the day in adults with DSM-5 ADHD. METHOD/UNASSIGNED:This was a 6-week pilot study that included 3 weeks of open label treatment with SDX/d-MPH (39.2/7.8 mg/day to 52.3/10.4 mg/day in clinical titration) after completion of a one-week screening period and a two-week observation period in seventeen adults with ADHD. Two subjects were discontinued from the trial, one for being placebo-responder and another for exhibiting blood pressure lability during the observation period. Of the remaining 15 subjects, one dropped out after one week on 39.2/7.8 mg/day, while all others completed the trial. All fifteen participants were included in the data analyses. RESULTS/UNASSIGNED:There were substantial effects of SDX/d-MPH on all clinical measures, including investigator symptom scores (AISRS); self-report (ASRS) scores, time-sensitive ADHD (TASS) scores throughout the day, impairment (CGI) and executive function scores (BRIEF-A) and measures of medication smoothness (AMSES). SDX/d-MPH was generally well tolerated. CONCLUSIONS/UNASSIGNED:This pilot study is the first systematic treatment effect trial data for SDX/d-MPH in adults with DSM-5 ADHD. The data preliminarily supports the clinical efficacy of DSM/d-MPH in adult ADHD and its ability to ameliorate symptoms throughout the day.

OBJECTIVE:Childhood inhibited temperament (cIT) is associated with an increased risk for developing internalizing psychopathology. Neurobiological characteristics identified by structural magnetic resonance imaging (MRI) may elucidate the neural substrates for cIT, but studies are scarce and often focus on particular regions of interest. Moreover, current findings lack replication. This pre-registered analysis from the ENIGMA-Anxiety Working Group examined structural brain characteristics associated with cIT using a comprehensive whole-brain approach. METHOD/METHODS:Temperament assessments (behavioral observations, parental/teacher reports or self-reports on cIT before age 13) and MRI-data (age at scan: 6-25 years) from international research sites (Europe, North America, South America) were pooled for mega-analysis. Following image processing and quality control, associations between cIT and brain structure were examined in 3,803 participants. Subcortical volumes, cortical thickness and surface area (main analyses) and detailed subcortical characteristics (e.g. subnuclei, subfields, partial volume effects; exploratory analyses) were considered. RESULTS:= 0.029) in youth with parental/teacher reports on cIT-levels. Exploratory analyses revealed findings in hippocampus, putamen and caudate, but most did not survive statistical correction for multiple testing. CONCLUSION/CONCLUSIONS:This mega-analysis found no consistent associations between cIT and regional brain structure, although the role of parietal regions warrants further investigation. Future studies should consider brain function in cIT, preferably using longitudinal designs.

Human cortical development follows a hierarchical, sensorimotor-to-association sequence. The brain's capacity to enact this sequence indicates that it relies on unknown mechanisms to regulate regional differences in the timing of cortical maturation. Given evidence from animal systems that thalamic axons mechanistically regulate periods of cortical plasticity, here we evaluate in humans whether the development of structural connections between the thalamus and cortex aligns with cortical maturational heterochronicity. By deriving a new tractography atlas of human thalamic connections and applying it to diffusion data from three youth samples (8-23 years; total n = 2,676), we demonstrate that thalamocortical connectivity matures in a generalizable manner along the cortex's sensorimotor-association axis. Associative cortical regions with thalamic connections that take the longest to mature exhibit neurochemical, structural and functional signatures of protracted developmental plasticity as well as heightened sensitivity to the socioeconomic environment. This work highlights the role of the thalamus in the expression of hierarchical periods of cortical developmental plasticity and environmental receptivity.

OBJECTIVE/UNASSIGNED:The Houston Conference Guidelines (Hannay et al., 1998) provided an initial framework for North American neuropsychology training that served the specialty well for several decades. Subsequent advances in technology, increased diversity of the U.S. and Canadian populations, and the adoption of competency-based training models within Health Service Psychology have created a need to update neuropsychology training guidelines. Therefore, in 2022, the Minnesota Conference to Update Education and Training Guidelines in Clinical Neuropsychology began a two-year drafting process leading to the currently proposed update. METHOD/UNASSIGNED:A Steering Committee worked with content experts, consultants, and delegates representing North American neuropsychological organizations and specialists. The final version of the guidelines was developed after reviewing neuropsychological training literature, gathering feedback from specialists, and making iterative revisions of earlier drafts to reach consensus. CONCLUSION/UNASSIGNED:The resulting "Minnesota Guidelines" include five foundational (Neuroscience and Brain Behavior Relationships; Integration of Science and Practice; Ethics, Standards, Laws, and Policies; Diversity; and Professional Relationships) and eight functional (Assessment; Intervention; Interdisciplinary Systems and Consultation; Research and Scholarship; Technology and Innovation; Teaching, Supervision, and Mentoring; Health and Professional Advocacy; and Administration, Management, and Business) areas of competency required for entry level specialty practice. While consensus was not achieved, a majority of voting delegates recommended the Guidelines for adoption and the Guidelines have been endorsed by six neuropsychology education and board certification organizations. The American Academy of Clinical Neuropsychology has not endorsed the Minnesota Guidelines and will not make an endorsement decision until three months after online publication.

Fetal iron status has long-lasting effects on neurodevelopmental outcomes and risk of psychopathology. Although prenatal exposure to maternal psychological stress has been linked to offspring peripheral iron status at birth, it is unknown whether maternal prenatal stress is related to fetal brain iron during gestation. We utilized 86 multi-echo functional magnetic resonance imaging (fMRI) scans from 52 fetuses (23 females; gestational age [GA] 24-38 weeks) to estimate R2* relaxometry as a proxy for fetal brain iron levels. Our results showed that greater maternal anxiety symptoms were associated with higher estimated fetal iron levels in the left cerebellar vermis after controlling for fetal sex and GA. Our finding suggests that fetal brain iron levels may be sensitive to exposure to maternal stress in utero. In a subset of participants with available infant outcome data (n = 31), no significant associations were found between fetal brain iron levels and later cognitive, language, and motor development during infancy. Overall, this study presents the first evidence of associations between maternal prenatal stress and fetal brain iron, which lays the groundwork for future investigations of biological embedding of prenatal maternal stress on the fetal brain and later neurodevelopment through prenatal iron accumulation as a potential mechanism.

Assessment of psychiatric symptoms relies on subjective self-report, which can be unreliable. Digital phenotyping collects data from smartphones to provide near-continuous behavioral monitoring. It can be used to provide objective information about an individual's mental state to improve clinical decision-making for both diagnosis and prognostication. The goal of this study was to evaluate the feasibility and acceptability of smartphone-based digital phenotyping for long-term mental health monitoring in adolescents with bipolar disorder and typically developing peers. Participants (aged 14-19) with bipolar disorder (BD) or with no mental health diagnoses were recruited for an 18-month observational study. Participants installed the Beiwe digital phenotyping app on their phones to collect passive data from their smartphone sensors and thrice-weekly surveys. Participants and caregivers were interviewed monthly to assess changes in the participant's mental health. Analyses focused on 48 participants who had completed participation. Average age at baseline was 15.85 years old (SD = 1.37). Approximately half (54%) identified as female, and 54% identified with a minoritized racial/ethnic background. Completion rates across data types were high, with 99% (826/835) of clinical interviews completed, 89% of passive data collected (22,233/25,029), and 47% (4,945/10,448) of thrice-weekly surveys submitted. The proportion of days passive data were collected was consistent over time for both groups; the clinical interview and active survey completion decreased over the study course. Results of this study suggest digital phenotyping has significant potential as a method of long-term mental health monitoring in adolescents. In contrast to traditional methods, including interview and self-report, it is lower burden and provides more complete data over time. A necessary next step is to determine how well the digital data capture changes in mental health to determine the clinical utility of this approach.

Altered fetal brain function is proposed as a mechanism underlying the relationship between prenatal maternal depression (PMD) and neurodevelopmental outcomes in offspring. This study investigated the association between PMD symptoms and fetal brain functional connectivity (FC) using graph theory. A total of 123 pregnant women participated in the study, completed the Center for Epidemiologic Studies Depression Scale (CES-D), and underwent fetal MRI scans. Results revealed a significant relationship between elevated PMD symptoms and reduced global efficiency in the right insular region of the fetal brain. However, because fetal age was not associated with local or global efficiency in the insular brain region, we cannot determine if the PMD-related reduction in insula global efficiency is indicative of an accelerated or delayed developmental pattern. This study is one of the few to examine fetal brain connectivity in relation to prenatal maternal depression, providing valuable insights into early neurodevelopmental risks and potential targets for early intervention.