Frontiers in Human Neuroscience最新文献

Metropolitan Mexico City (MMC) children and young adults exhibit overlapping Alzheimer and Parkinsons' diseases (AD, PD) and TAR DNA-binding protein 43 pathology with magnetic ultrafine particulate matter (UFPM) and industrial nanoparticles (NPs). We studied magnetophoresis, electron microscopy and energy-dispersive X-ray spectrometry in 203 brain samples from 14 children, 27 adults, and 27 ALS cases/controls. Saturation isothermal remanent magnetization (SIRM), capturing magnetically unstable FeNPs ~ 20nm, was higher in caudate, thalamus, hippocampus, putamen, and motor regions with subcortical vs. cortical higher SIRM in MMC ≤ 40y. Motion behavior was associated with magnetic exposures 25-100 mT and children exhibited IRM saturated curves at 50-300 mT associated to change in NPs position and/or orientation in situ. Targeted magnetic profiles moving under AC/AD magnetic fields could distinguish ALS vs. controls. Motor neuron magnetic NPs accumulation potentially interferes with action potentials, ion channels, nuclear pores and enhances the membrane insertion process when coated with lipopolysaccharides. TEM and EDX showed 7-20 nm NP Fe, Ti, Co, Ni, V, Hg, W, Al, Zn, Ag, Si, S, Br, Ce, La, and Pr in abnormal neural and vascular organelles. Brain accumulation of magnetic unstable particles start in childhood and cytotoxic, hyperthermia, free radical formation, and NPs motion associated to 30-50 μT (DC magnetic fields) are critical given ubiquitous electric and magnetic fields exposures could induce motion behavior and neural damage. Magnetic UFPM/NPs are a fatal brain cargo in children's brains, and a preventable AD, PD, FTLD, ALS environmental threat. Billions of people are at risk. We are clearly poisoning ourselves.

[This retracts the article DOI: 10.3389/fnhum.2022.886971.].

Past studies have explored formant centering, a corrective behavior of convergence over the duration of an utterance toward the formants of a putative target vowel. In this study, we establish the existence of a similar centering phenomenon for pitch in healthy elderly controls and examine how such corrective behavior is altered in Alzheimer's Disease (AD). We found the pitch centering response in healthy elderly was similar when correcting pitch errors below and above the target (median) pitch. In contrast, patients with AD showed an asymmetry with a larger correction for the pitch errors below the target phonation than above the target phonation. These findings indicate that pitch centering is a robust compensation behavior in human speech. Our findings also explore the potential impacts on pitch centering from neurodegenerative processes impacting speech in AD.

Empathy as one of the basic prerequisites for successful social interactions seems to be aberrant in individuals with major depressive disorder (MDD). Although understanding empathic impairments in MDD is crucial considering the frequently reported social skill deficits in patients, the current state of research is still inconclusive, pointing to both elevated and impaired levels of empathy. In this review, we extend previous reports of MDD-related aberrations in self-reported and behavioral empathy by shedding light on the neural correlates of empathy in MDD. Study findings indicate a complex and potentially state-dependent association, comprising both elevated and lower neural activity in empathy-related brain regions such as the inferior frontal gyri, bilateral anterior insulae, and cingulate areas. Predominantly, lower activity in these areas seems to be induced by antidepressant treatment or remission, with accompanying behavioral results indicating a reduced negativity-bias in empathic processing compared to acute states of MDD. We propose a preliminary model of empathy development throughout the course of the disorder, comprising initially elevated levels of empathy and a somewhat detached and lower empathic responding during the further progression of the disorder or post-treatment. The seemingly multifaceted nature of the association between empathy and MDD requires further exploration in future multimodal and longitudinal studies. The study of neural correlates of empathy in MDD should prospectively be enlarged by including further socio-affective and -cognitive capacities in MDD and related mental disorders.