Faculty Bibliography

OBJECTIVES/OBJECTIVE:Developmentally specified measures that identify clinically salient irritability are needed for early school-age youth to meaningfully capture this transdiagnostic risk factor for psychopathology. Thus, the current study modeled the normal:abnormal irritability spectrum and generated a clinically optimized screening tool for this population. METHODS:The irritability spectrum was modeled via the youth version of the Multidimensional Assessment Profile Scales-Temper Loss Scale (MAPS-TL-Youth) in children (n = 474; 6.0-8.9 years) using item response theory (IRT). Both cross-cutting core irritability items from the early childhood version and new developmentally specific items were included. Items uniquely associated with impairment were identified and used to derive a brief, clinically optimized irritability screener. Longitudinal data were then utilized to test the predictive utility of this clinically optimized screener in preadolescence (n = 348; 8.0-12.9 years). RESULTS:Most children exhibit irritability regularly, but daily occurrence was rare. Of the top 10 most severe items from the IRT analyses, 9 were from the developmentally specific items added for the MAPS-TL Youth version. Two items associated with concurrent impairment were identified for the clinically optimized irritability screener ("Become frustrated easily" and "Act irritable"). The MAPS-TL-Youth clinically optimized screener demonstrated good sensitivity (69%) and specificity (84%) in relation to concurrent DSM 5 irritability-related diagnoses. Youth with elevated scores on the screener at early school age (ESA) had more than 7x greater odds of irritability-related psychopathology at pre-adolescence. CONCLUSIONS:The MAPS-TL-Youth characterized the developmental spectrum of irritability at ESA and a clinically optimized screener showed promise at predicting psychopathology risk. Rigorous testing of clinical applications is a critical next step.

BACKGROUND:The striatal-pallidal pathway plays an important role in cognitive control and modulation of behaviors. Globus pallidus interna (GPi), as a primary output structure, is crucial in modulating excitation and inhibition. Studies of GPi in psychiatric illnesses are lacking given the technical challenges of examining this small and functionally diverse subcortical structure. METHODS:71 medication-naïve first episode schizophrenia (FES) participants and 73 healthy controls (HC) were recruited at the Shanghai Mental Health Center. Clinical symptoms and imaging data were collected at baseline and, in a subset of patients, 8 weeks after initiating treatment. Resting-state functional connectivity of sub-regions of the GP were assessed using a novel mask that combines two atlases to create 8 ROIs in the GP. RESULTS: = 0.486, p < 0.001). CONCLUSIONS:Our results implicate striatal-pallidal-thalamic pathways in antipsychotic efficacy. If replicated, these findings may reflect failure of neurodevelopmental processes in adolescence and early adulthood that decrease functional connectivity as an index of failure of the limbic/associative GPi to appropriately inhibit irrelevant signals in psychosis.

OBJECTIVES/OBJECTIVE:Heightened irritability in adolescence is an impairing symptom that can lead to negative outcomes in adulthood, but effective screening tools are lacking. This study aimed to derive clinically-optimized cutoff scores using the Multidimensional Assessment Profile Scales-Temper Loss (MAPS-TL) to pragmatically identify adolescents with impairing irritability. METHODS:A diverse sample of 79 adolescents and their parents completed the MAPS-TL-Youth version. Stepwise logistic regression analyses were used to determine the items associated with impairment, and receiver operator characteristic (ROC) analyses were conducted to derive optimal cutoff scores. RESULTS:Three parent-report items (become frustrated easily, angry/irritable/grouchy throughout the day, difficulty calming down when angry) and two youth-report items (hit/shove/kick when lost temper, difficulty calming down when angry) were strongly associated with impairment. Optimal cutoff scores garnered very good sensitivity (91%, 73%) and specificity (77%, 75%) for the parent- and youth-report versions respectively. Scores above these cutoffs were associated with increased internalizing and externalizing problems and lower overall quality of life. CONCLUSIONS:The MAPS-TL clinically optimized irritability scores show preliminary validity for implementation in practical settings to efficiently identify adolescents who need additional evaluation and/or intervention. Further research is important to validate these cutoff scores with larger population-based samples and real-world settings.

OBJECTIVE/UNASSIGNED:To document the experience of 14 academic child and adolescent psychiatry programs in transitioning to and managing telehealth services during the COVID-19 pandemic. The goal was to understand how programs adopted and sustained telehealth during the pandemic. Telehealth was defined as services delivered via videoconferencing and telephony. METHOD/UNASSIGNED:In this descriptive study, faculty from 14 programs completed online surveys about the use of both telehealth and in-person services from February 2020 to June 2021. Survey questions addressed telehealth practices (e.g., policies, support resources), monthly service utilization, telehealth modality (videoconferencing vs. telephony), and missed appointments. RESULTS/UNASSIGNED:Programs varied in the proportion of appointments delivered by telehealth prior to the pandemic (February 2020; 0-27%). By May 2020 all programs were providing a majority of visits via telehealth (64-100%). In June 2021, all programs continued to provide services via telehealth (41% to 100%) and reported that they would continue to do so moving forward. Programs addressed many challenges to telehealth provision during the study period, including adding interpreter services, technological support for providers and patients, and formalizing safety and training requirements. CONCLUSION/UNASSIGNED:Academic child and adolescent psychiatry programs provided outpatient services primarily via telehealth throughout the COVID-19 pandemic and reported that they planned to continue utilizing telehealth in combination with in-person services moving forward. Academic programs should therefore address logistical, technological, and financial barriers to the sustained use of telehealth.

Caregivers often tailor their language to infants' ongoing actions (e.g., "are you stacking the blocks?"). When infants develop new motor skills, do caregivers show concomitant changes in their language input? We tested whether the use of verbs that refer to locomotor actions (e.g., "come," "bring," "walk") differed for mothers of 13-month-old crawling (N = 16) and walking infants (N = 16), and mothers of 18-month-old experienced walkers (N = 16). Mothers directed twice as many locomotor verbs to walkers compared to same-age crawlers, but mothers' locomotor verbs were similar for younger and older walkers. In real-time, mothers' use of locomotor verbs was dense when infants were locomoting, and sparse when infants were stationary, regardless of infants' crawler/walker status. Consequently, infants who spent more time in motion received more locomotor verbs compared to infants who moved less frequently. Findings indicate that infants' motor skills guide their in-the-moment behaviors, which in turn shape the language they receive from caregivers. RESEARCH HIGHLIGHTS: Infants' motor skills guide their in-the-moment behaviors, which in turn shape the language they receive from caregivers. Mothers directed more frequent and diverse verbs that referenced locomotion (e.g., "come," "go," "bring") to walking infants compared to same-aged crawling infants. Mothers' locomotor verbs were temporally dense when infants locomoted and sparse when infants were stationary, regardless of whether infants could walk or only crawl.

Down syndrome (DS) is a genetic disorder caused by triplication of human chromosome 21. In addition to intellectual disability, DS is defined by a premature aging phenotype and Alzheimer's disease (AD) neuropathology, including septohippocampal circuit vulnerability and degeneration of basal forebrain cholinergic neurons (BFCNs). The Ts65Dn mouse model recapitulates key aspects of DS/AD pathology, namely age-associated atrophy of BFCNs and cognitive decline in septohippocampal-dependent behavioral tasks. We investigated whether maternal choline supplementation (MCS), a well-tolerated treatment modality, protects vulnerable BFCNs from age- and genotype-associated degeneration in trisomic offspring. We also examined the effect of trisomy, and MCS, on GABAergic basal forebrain parvalbumin neurons (BFPNs), an unexplored neuronal population in this DS model. Unbiased stereological analyses of choline acetyltransferase (ChAT)-immunoreactive BFCNs and parvalbumin-immunoreactive BFPNs were conducted using confocal z-stacks of the medial septal nucleus and the vertical limb of the diagonal band (MSN/VDB) in Ts65Dn mice and disomic (2N) littermates at 3-4 and 10-12 months of age. MCS trisomic offspring displayed significant increases in ChAT-immunoreactive neuron number and density compared to unsupplemented counterparts, as well as increases in the area of the MSN/VDB occupied by ChAT-immunoreactive neuropil. MCS also rescued BFPN number and density in Ts65Dn offspring, a novel rescue of a non-cholinergic cell population. Furthermore, MCS prevented age-associated loss of BFCNs and MSN/VDB regional area in 2N offspring, indicating genotype-independent neuroprotective benefits. These findings demonstrate MCS provides neuroprotection of vulnerable BFCNs and non-cholinergic septohippocampal BFPNs, indicating this modality has translational value as an early life therapy for DS, as well as extending benefits to the aging population at large.

Data on incidence, prevalence and burden of ADHD are crucial for clinicians, patients, and stakeholders. We present the incidence, prevalence, and burden of ADHD globally and across countries from 1990 to 2019 from the Global Burden of Disease (GBD) study. We also: (1) calculated the ADHD prevalence based on data actually collected as opposed to the prevalence estimated by the GBD with data imputation for countries without prevalence data; (2) discussed the GBD estimated ADHD burden in the light of recent meta-analytic evidence on ADHD-related mortality. In 2019, GBD estimated global age-standardized incidence and prevalence of ADHD across the lifespan at 0.061% (95%UI = 0.040-0.087) and 1.13% (95%UI = 0.831-1.494), respectively. ADHD accounted for 0.8% of the global mental disorder DALYs, with mortality set at zero by the GBD. From 1990 to 2019 there was a decrease of -8.75% in the global age-standardized prevalence and of -4.77% in the global age-standardized incidence. The largest increase in incidence, prevalence, and burden from 1990 to 2019 was observed in the USA; the largest decrease occurred in Finland. Incidence, prevalence, and DALYs remained approximately 2.5 times higher in males than females from 1990 to 2019. Incidence peaked at age 5-9 years, and prevalence and DALYs at age 10-14 years. Our re-analysis of data prior to 2013 showed a prevalence in children/adolescents two-fold higher (5.41%, 95% CI: 4.67-6.15%) compared to the corresponding GBD estimated prevalence (2.68%, 1.83-3.72%), with no significant differences between low- and middle- and high-income countries. We also found meta-analytic evidence of significantly increased ADHD-related mortality due to unnatural causes. While it provides the most detailed evidence on temporal trends, as well as on geographic and sex variations in incidence, prevalence, and burden of ADHD, the GBD may have underestimated the ADHD prevalence and burden. Given the influence of the GBD on research and policies, methodological issues should be addressed in its future editions.

Developmental neural activity organizes sensory system development. New evidence in mice suggests postnatal olfactory bulb activity also modulates development of the structure and function of hippocampal-cortical circuits. Reducing cell-specific olfactory bulb output during an infant sensitive period impairs later-life cognition.

Interictal spikes (IIS) are a common type of abnormal electrical activity in Alzheimer's disease (AD) and preclinical models. The brain regions where IIS are largest are not known but are important because such data would suggest sites that contribute to IIS generation. Because hippocampus and cortex exhibit altered excitability in AD models, we asked which areas dominate the activity during IIS along the cortical-CA1-dentate gyrus (DG) dorso-ventral axis. Because medial septal (MS) cholinergic neurons are overactive when IIS typically occur, we also tested the novel hypothesis that silencing the MS cholinergic neurons selectively would reduce IIS. We used mice that simulate aspects of AD: Tg2576 mice, presenilin 2 (PS2) knockout mice and Ts65Dn mice. To selectively silence MS cholinergic neurons, Tg2576 mice were bred with choline-acetyltransferase (ChAT)-Cre mice and offspring were injected in the MS with AAV encoding inhibitory designer receptors exclusively activated by designer drugs (DREADDs). We recorded local field potentials along the cortical-CA1-DG axis using silicon probes during wakefulness, slow-wave sleep (SWS) and rapid eye movement (REM) sleep. We detected IIS in all transgenic or knockout mice but not age-matched controls. IIS were detectable throughout the cortical-CA1-DG axis and occurred primarily during REM sleep. In all 3 mouse lines, IIS amplitudes were significantly greater in the DG granule cell layer vs. CA1 pyramidal layer or overlying cortex. Current source density analysis showed robust and early current sources in the DG, and additional sources in CA1 and the cortex also. Selective chemogenetic silencing of MS cholinergic neurons significantly reduced IIS rate during REM sleep without affecting the overall duration, number of REM bouts, latency to REM sleep, or theta power during REM. Notably, two control interventions showed no effects. Consistent maximal amplitude and strong current sources of IIS in the DG suggest that the DG is remarkably active during IIS. In addition, selectively reducing MS cholinergic tone, at times when MS is hyperactive, could be a new strategy to reduce IIS in AD.

A significant proportion of temporal lobe epilepsy (TLE) patients experience drug-resistant seizures associated with mesial temporal sclerosis, in which there is extensive cell loss in the hippocampal CA1 and CA3 subfields, with a relative sparing of dentate gyrus granule cells and CA2 pyramidal neurons (PNs). A role for CA2 in seizure generation was suggested based on findings of a reduction in CA2 synaptic inhibition (Williamson and Spencer, 1994) and the presence of interictal-like spike activity in CA2 in resected hippocampal tissue from TLE patients (Wittner et al., 2009). We recently found that in the pilocarpine-induced status epilepticus (PILO-SE) mouse model of TLE there was an increase in CA2 intrinsic excitability associated with a loss of CA2 synaptic inhibition. Furthermore, chemogenetic silencing of CA2 significantly reduced seizure frequency, consistent with a role of CA2 in promoting seizure generation and/or propagation (Whitebirch et al., 2022). In the present study, we explored the cellular basis of this inhibitory deficit using immunohistochemical and electrophysiological approaches in PILO-SE male and female mice. We report a widespread decrease in the density of pro-cholecystokinin-immunopositive (CCK⁺) interneurons and a functional impairment of CCK⁺ interneuron-mediated inhibition of CA2 PNs. We also found a disruption in the perisomatic perineuronal net in the CA2 stratum pyramidale. Such pathologic alterations may contribute to an enhanced excitation of CA2 PNs and CA2-dependent seizure activity in the PILO-SE mouse model.SIGNIFICANCE STATEMENT Impaired synaptic inhibition in hippocampal circuits has been identified as a key feature that contributes to the emergence and propagation of seizure activity in human patients and animal models of temporal lobe epilepsy (TLE). Among the hippocampal subfields, the CA2 region is particularly resilient to seizure-associated neurodegeneration and has been suggested to play a key role in seizure activity in TLE. Here we report that perisomatic inhibition of CA2 pyramidal neurons mediated by cholecystokinin-expressing interneurons is selectively reduced in acute hippocampal slices from epileptic mice. Parvalbumin-expressing interneurons, in contrast, appear relatively conserved in epileptic mice. These findings advance our understanding of the cellular mechanisms underlying inhibitory disruption in hippocampal circuits in a mouse model of spontaneous recurring seizures.