Pubmed (TDAH) du 05/06/26
1. Alger JR, Gupta I, Farkouh L, Korthas J, Shah A, Silverberg A, Salamon N, Schneider BN, Joshi SH, O’Connor MJ, O’Neill J. Anterior middle cingulate cortex gamma-aminobutyric acid level is elevated in children with both familial and prenatal alcohol exposure-associated attention deficit hyperactivity disorder. medRxiv. 2026.
BACKGROUND: Prior neuroimaging suggests brain differences between children with attention deficit hyperactivity disorder due to prenatal alcohol exposure (ADHD+PAE) and non-exposed children with ADHD due to other, e.g., familial, causes (ADHD-PAE). There has been interest in regional brain levels of gamma-aminobutyric acid (GABA) and glutamate (Glu) measured in vivo with magnetic resonance spectroscopy (MRS) as possible indicators of local inhibitory, respectively, excitatory activity in ADHD. For the first time, we report here a comparison of GABA and Glu in ADHD+PAE vs. ADHD-PAE. METHODS: At 3 T, we used J-difference-edited single-voxel MRS to assay GABA and Glu in 28 children with ADHD+PAE, 20 with ADHD-PAE, and 28 typically developing (TD) controls, all aged 8-14 years. MRS was sampled from midline anterior middle cingulate cortex (aMCC), the « cognitive cingulate » considered functionally relevant to ADHD. Spectra were fit with custom software, including a unique technique for isolating the GABA signal from the confounding macromolecular baseline (MMBL). RESULTS: aMCC GABA was higher in ADHD+PAE and ADHD-PAE than in TD. GABA increased with age in TD, but not in ADHD+PAE or ADHD-PAE. Similar effects were observed for the ratios GABA/Glu and GABA/Glx. For GABA+MMBL (GABA+) these effects were not seen, rather GABA+ and MMBL increased with age for the ADHD+PAE group only. No significant effects were found for Glu or Glx. CONCLUSIONS: GABA in the aMCC does not distinguish the two etiologies of ADHD, rather elevated GABA that follows an abnormal developmental appears to be common to both. High GABA may reflect increased inhibition of the aMCC impairing its cognitive functions. GABA+ results in ADHD may not tract reliably with underlying GABA values. Negative results for Glu and Glx should be reexamined at shorter echo-times.
Lien vers le texte intégral (Open Access ou abonnement)
2. Feier DS, Gilbert DL, Crocetti D, Migneault KY, Huddleston DA, Horn PS, Mostofsky SH, Wu SW. Shortened Cortical Silent Period in Children with Attention Deficit Hyperactivity Disorder. medRxiv. 2026.
BACKGROUND AND OBJECTIVE: In ADHD, a heterogeneous neurodevelopmental condition, behavioral and motor manifestations may reflect multiple inefficient or perturbed inhibitory systems. To evaluate Transcranial Magnetic Stimulation (TMS) evoked cortical silent period (CSP) duration, an indicator of GABA (B) receptor-mediated inhibition in motor cortex, as a potential biomarker of Attention-Deficit/Hyperactivity Disorder (ADHD) in children. METHOD: We retrospectively analyzed TMS data, obtained using both round and figure-of-8 coils, from three cross-sectional studies conducted in 8- to 12-year-old children with ADHD (n=79; 10.7 +/- 1.5 years old) and age-and-sex-matched typically-developing controls (n=96; 10.5 +/- 1.4 years old). RESULTS: Median CSP was 32% shorter in ADHD (p=0.02). Regression analysis demonstrated a relationship between shorter CSP and both lower active motor thresholds (p < 0.0001) and more severe hyperactivity symptom rating (p = 0.026). Test-retest CSP measures in 83 children showed moderate reliability (intraclass correlation 0.77 [ADHD], 0.75 [controls]). CONCLUSION: TMS-evoked CSP may be a useful biomarker in future investigations of ADHD subtypes, domains of impaired function, or treatment outcomes.
Lien vers le texte intégral (Open Access ou abonnement)
3. Gupta I, Farkouh L, Kilpatrick L, Korthas J, Salamon N, Schneider BN, Joshi SH, Alger JR, O’Connor MJ, O’Neill J. Distinct Resting-State Functional Connectivity Profiles in ADHD with and without Prenatal Alcohol Exposure. medRxiv. 2026.
AIM: To determine whether the neural phenotype (whole-brain resting-state functional connectivity pattern) of attention-deficit/hyperactivity disorder associated with prenatal alcohol exposure (ADHD-PAE) differs from that in unexposed children with ADHD of probable familial origin (ADHD-PAE). METHOD: Resting-state functional MRI was acquired from 26 children with ADHD+PAE, 25 with ADHD-PAE and 25 typically developing (TD) children, all aged 8-13 years. Mean connectivity matrices based on the Cole-Anticevic Brainwide Network Parcellation of the brain were compared between the groups. RESULTS: Within the frontoparietal network (FPN), children with ADHD+PAE showed widespread lower group-mean connectivity than children with ADHD-PAE; effects were concentrated primarily in cerebellar-cerebral cortical and cerebral cortical-cerebral cortical connections. Children with ADHD-PAE showed widespread hyperconnectivity relative to TD children. Children with ADHD+PAE showed mixed hyper- and hypoconnectivity relative to TD. INTERPRETATION: These results are consistent with other MRI findings indicating that ADHD+PAE is neurally distinct from ADHD-PAE; PAE may be associated with broadly reduced connectivity, especially across cerebellar-cerebral cortical systems.
Lien vers le texte intégral (Open Access ou abonnement)
4. Johnson JA, Sudhir PM, Arumugham SS, Yadav R. Prioritizing sleep in adult ADHD: Addressing clinical priority and therapeutic gap. Asian J Psychiatr. 2026; 122: 105029.
