Bilateral Temporal Regions Research Articles

Functional Brain Adaptations During Speech Processing in 4-Month-Old Bilingual Infants.

Language learning is influenced by both neural development and environmental experiences. This work investigates the influence of early bilingual experience on the neural mechanisms underlying speech processing in 4-month-old infants. We study how an early environmental factor such as bilingualism interacts with neural development by comparing monolingual and bilingual infants' brain responses to speech. We used functional near-infrared spectroscopy (fNIRS) to measure 4-month-old Spanish-Basque bilingual and Spanish monolingual infants' brain responses while they listened to forward (FW) and backward (BW) speech stimuli in Spanish. We reveal distinct neural signatures associated with bilingual adaptations, including increased engagement of bilateral inferior frontal and temporal regions during speech processing in bilingual infants, as opposed to left hemispheric functional specialization observed in monolingual infants. This study provides compelling evidence of bilingualism-induced brain adaptations during speech processing in infants as young as 4 months. These findings emphasize the role of early language experience in shaping neural plasticity during infancy suggesting that bilingual exposure at this young age profoundly influences the neural mechanisms underlying speech processing.

Characteristics of Alzheimer’s Disease and Mild Cognitive Impairment Influenced by the Time of Onset

Introduction: Although the prevalence of Alzheimer’s disease (AD) is higher in older people compared to younger people, dementia has also been documented in younger adults. Although early-onset dementia and late-onset dementia had been considered a single disease in pathological investigations, many studies revealed differences in cognitive and neuroimaging changes between them. We evaluated differences in cognitive and neuroimaging changes among the following groups: individuals with early-onset AD (EOAD), late-onset AD (LOAD), early-onset mild cognitive impairment (EOMCI), or late-onset MCI (LOMCI), and healthy controls (HCs). Methods: Patients underwent both a 1.5 Tesla magnetic resonance imaging scan and the Mini-Mental State Examination (MMSE). Differences in regional gray matter volumes and MMSE subscales were investigated among the five diagnostic groups. Results: Compared to the EOAD group, the LOAD group had significantly higher scores on orientation in place. Compared to the LOMCI patients, the EOMCI patients achieved significantly higher recall scores. The LOAD and LOMC groups showed significant volume reductions in bilateral medial temporal regions compared to the HCs. The EOAD and EOMCI groups did not show significant atrophy of the medial temporal region compared to the HC group. Conclusions: The hippocampal volume and memory were preserved in the patients with EOMCI or EOAD compared to those with LOMCI or LOAD. These findings may indicate that the distinct and differing patterns of neuropsychological changes between EOAD and LOAD are also common in MCI, which is intermediate between normal cognition and AD.

Repetitive Transcranial Magnetic Stimulation Modulates Brain Connectivity in Children with Self-limited Epilepsy with Centrotemporal Spikes.

Interictal epileptiform discharges (IEDs) alter brain connectivity in children with epilepsy; this connectivity change may be a mechanism by which epilepsy induces cognitive deficits. Here, we test whether repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, modulates connectivity and reduces IEDs in children with epilepsy. Nineteen children with self-limited epilepsy with centrotemporal spikes (SeLECTS) participated in a cross-over study comparing the impact of active vs. sham rTMS on IEDs and brain connectivity. SeLECTS is an epilepsy syndrome affecting the motor cortex, and prior studies show that motor cortices become pathologically hyper-connected to frontal and temporal language cortices. Using a crossover design, we compared the effect of single doses of active versus sham motor cortex rTMS. Connectivity, which was quantified by the weighted phase lag index (wPLI), was measured before and after rTMS using single pulses of TMS combined with EEG (spTMS-EEG). Analyses focused on six regions: bilateral motor cortices and bilateral inferior frontal and superior temporal regions. IEDs were counted in the five minutes before and after rTMS. Active, but not sham, rTMS significantly and globally decreased wPLI connectivity between multiple regions, with the greatest reductions seen in the superior temporal region connections in the stimulated hemisphere. Additionally, there was a trend suggesting that rTMS decreases IED frequency. These findings underscore the potential of low-frequency rTMS to target pathologic hyperconnectivity and reduce IEDs in children with SeLECTS and potentially other pediatric epilepsy syndromes, offering a promising avenue for therapeutic intervention.

Language networks of normal-hearing infants exhibit topological differences between resting and steady states: An fNIRS functional connectivity study.

Task-related studies have consistently reported that listening to speech sounds activate the temporal and prefrontal regions of the brain. However, it is not well understood how functional organization of auditory and language networks differ when processing speech sounds from its resting state form. The knowledge of language network organization in typically developing infants could serve as an important biomarker to understand network-level disruptions expected in infants with hearing impairment. We hypothesized that topological differences of language networks can be characterized using functional connectivity measures in two experimental conditions (1) complete silence (resting) and (2) in response to repetitive continuous speech sounds (steady). Thirty normal-hearing infants (14 males and 16 females, age: 7.8 ± 4.8 months) were recruited in this study. Brain activity was recorded from bilateral temporal and prefrontal regions associated with speech and language processing for two experimental conditions: resting and steady states. Topological differences of functional language networks were characterized using graph theoretical analysis. The normalized global efficiency and clustering coefficient were used as measures of functional integration and segregation, respectively. We found that overall, language networks of infants demonstrate the economic small-world organization in both resting and steady states. Moreover, language networks exhibited significantly higher functional integration and significantly lower functional segregation in resting state compared to steady state. A secondary analysis that investigated developmental effects of infants aged 6-months or below and above 6-months revealed that such topological differences in functional integration and segregation across resting and steady states can be reliably detected after the first 6-months of life. The higher functional integration observed in resting state suggests that language networks of infants facilitate more efficient parallel information processing across distributed language regions in the absence of speech stimuli. Moreover, higher functional segregation in steady state indicates that the speech information processing occurs within densely interconnected specialized regions in the language network.

Associations of polygenic risk scores differentiating attention-deficit hyperactivity disorder from autism spectrum disorder with cognitive and cortical alterations in Schizophrenia patients.

Schizophrenia (SCZ) is a clinically and genetically heterogeneous disorder that shares genetic factors with autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). A genome-wide association study (GWAS) differentiating ADHD from ASD was performed recently. In this study, we investigated whether polygenic risk scores (PRSs) differentiating ASD from ADHD are associated with cognitive impairments and alterations in cortical structures in SCZ patients. Based on the GWAS data (9,315 ASD and 11,964 ADHD patients), PRSs differentiating ADHD from ASD (indicating a greater risk of ADHD and a lower risk of ASD) were calculated for SCZ patients (n = 168). Cognitive performance, including verbal comprehension (VC), perceptual organization (PO), working memory (WM), and processing speed (PS), was assessed using the WAIS-III (n = 145). The surface areas and cortical thicknesses of 34 bilateral brain regions were extracted using FreeSurfer (n = 126). We examined the associations of these PRSs with cognitive performance and cortical structures in SCZ patients. Among the four cognitive domains, a higher PRS, indicating a greater risk of ADHD, was associated with impaired WM in SCZ patients (beta=-0.21, p = 0.012). A lower PRS, indicating a greater risk of ASD, was associated with decreased surface areas of the left medial orbitofrontal (beta = 0.21, p = 8.29 × 10- 4), left entorhinal (beta = 0.21, p = 0.025), left postcentral (beta = 0.18, p = 7.52 × 10- 3), right fusiform (beta = 0.17, p = 6.64 × 10- 3), and left fusiform cortices (beta = 0.17, p = 7.77 × 10- 3) in SCZ patients. A higher PRS, indicating a greater risk of ADHD, was associated with decreased cortical thickness in the bilateral transverse temporal regions (left, beta=-0.17, p = 0.039; right, beta=-0.17, p = 0.045). Our study revealed a relationship between genetic factors that differentiate ADHD patients from ASD patients and both cortical structure and cognitive performance in SCZ patients. These findings suggest that the heterogeneity of SCZ might be partly derived from genetic factors related to neurodevelopmental and psychiatric disorders other than SCZ.

Differential reorganization of episodic and semantic memory systems in epilepsy-related mesiotemporal pathology.

Declarative memory encompasses episodic and semantic divisions. Episodic memory captures singular events with specific spatiotemporal relationships, while semantic memory houses context-independent knowledge. Behavioural and functional neuroimaging studies have revealed common and distinct neural substrates of both memory systems, implicating mesiotemporal lobe (MTL) regions such as the hippocampus and distributed neocortices. Here, we explored declarative memory system reorganization in patients with unilateral temporal lobe epilepsy (TLE) as a human disease model to test the impact of variable degrees of MTL pathology on memory function. Our cohort included 31 patients with TLE as well as 60 age and sex-matched healthy controls, and all participants underwent episodic and semantic retrieval tasks during a multimodal MRI session. The functional MRI tasks were closely matched in terms of stimuli and trial design. Capitalizing on non-linear connectome gradient mapping techniques, we derived task-based functional topographies during episodic and semantic memory states, both in the MTL and in neocortical networks. Comparing neocortical and hippocampal functional gradients between TLE patients and healthy controls, we observed a marked topographic reorganization of both neocortical and MTL systems during episodic memory states. Neocortical alterations were characterized by reduced functional differentiation in TLE across lateral temporal and midline parietal cortices in both hemispheres. In the MTL, on the other hand, patients presented with a more marked functional differentiation of posterior and anterior hippocampal segments ipsilateral to the seizure focus and pathological core, indicating perturbed intrahippocampal connectivity. Semantic memory reorganization was also found in bilateral lateral temporal and ipsilateral angular regions, while hippocampal functional topographies were unaffected. Leveraging MRI proxies of MTL pathology, we furthermore observed alterations in hippocampal microstructure and morphology that were associated with TLE-related functional reorganization during episodic memory. Moreover, correlation analysis and statistical mediation models revealed that these functional alterations contributed to behavioural deficits in episodic, but again not semantic memory in patients. Altogether, our findings suggest that semantic processes rely on distributed neocortical networks, while episodic processes are supported by a network involving both the hippocampus and neocortex. Alterations of such networks can provide a compact signature of state-dependent reorganization in conditions associated with MTL damage, such as TLE.

Functional MRI-based biomarkers of insomnia with objective short sleep duration phenotype

BackgroundInsomnia disorder with objective short sleep duration (ISS) phenotype is a more serious biological subtype than insomnia with objective normal sleep duration (INS) phenotype, and the neuroimaging data is helpful to understand the pathophysiology of the ISS phenotype. This study was to compare the amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and functional connectivity (FC) between the ISS phenotype and the INS phenotype. MethodsIn this cross-sectional study, 55 patients with insomnia disorder were recruited, and 22 of them were defined as the ISS phenotype by the objective cardiopulmonary coupling (CPC) technique. The blood oxygen level-dependent (BOLD) sequences of all participants were obtained using the 3.0 T magnetic resonance imaging system. We analyzed and compared the ALFF, ReHo, and FC between the ISS phenotype and the INS phenotype. We also conducted Pearson's correlation analysis between significant neuroimaging biomarkers and the CPC parameters. ResultsThe differences were not significant in ALFF (PFWE-corr＞0.05) or ReHo (PFWE-corr＞0.05) between the ISS phenotype and the INS phenotype. For the FC analysis, the ISS phenotype had a Hub-node of the left inferior occipital gyrus (IOG.L), with significantly decreased connections (p＜0.001) in the bilateral occipital, parietal, and temporal regions. The significant FCs were closely related to sleep parameters. ConclusionThe left inferior occipital gyrus (IOG.L), as a Hub-node with decreased functional connections, may be a potential fMRI-based biomarker of the ISS phenotype.

Auditory hemispheric asymmetry for actions and objects.

What is the function of auditory hemispheric asymmetry? We propose that the identification of sound sources relies on the asymmetric processing of two complementary and perceptually relevant acoustic invariants: actions and objects. In a large dataset of environmental sounds, we observed that temporal and spectral modulations display only weak covariation. We then synthesized auditory stimuli by simulating various actions (frictions) occurring on different objects (solid surfaces). Behaviorally, discrimination of actions relies on temporal modulations, while discrimination of objects relies on spectral modulations. Functional magnetic resonance imaging data showed that actions and objects are decoded in the left and right hemispheres, respectively, in bilateral superior temporal and left inferior frontal regions. This asymmetry reflects a generic differential processing-through differential neural sensitivity to temporal and spectral modulations present in environmental sounds-that supports the efficient categorization of actions and objects. These results support an ecologically valid framework of the functional role of auditory brain asymmetry.

Excitation/Inhibition balance relates to cognitive function and gene expression in temporal lobe epilepsy: a high density EEG assessment with aperiodic exponent.

Patients with epilepsy are characterized by a dysregulation of excitation/inhibition balance (E/I). The assessment of E/I may inform clinicians during the diagnosis and therapy management, even though it is rarely performed. An accessible measure of the E/I of the brain represents a clinically relevant feature. Here, we exploited the exponent of the aperiodic component of the power spectrum of the electroencephalography (EEG) signal, as a non-invasive and cost-effective proxy of the E/I balance. We recorded resting-state activity with high-density EEG from 67 patients with temporal lobe epilepsy and 35 controls. We extracted the exponent of the aperiodic fit of the power spectrum from source-reconstructed EEG and tested differences between patients with epilepsy and controls. Spearman's correlation was performed between the exponent and clinical variables (age of onset, epilepsy duration and neuropsychology) and cortical expression of epilepsy-related genes derived from the Allen Human Brain Atlas. Patients with temporal lobe epilepsy showed a significantly larger exponent, corresponding to inhibition-directed E/I balance, in bilateral frontal and temporal regions. Lower E/I in the left entorhinal and bilateral dorsolateral prefrontal cortices corresponded to a lower performance of short-term verbal memory. Limited to patients with temporal lobe epilepsy, we detected a significant correlation between the exponent and the cortical expression of GABRA1, GRIN2A, GABRD, GABRG2, KCNA2 and PDYN genes. EEG aperiodic exponent maps the E/I balance non-invasively in patients with epilepsy and reveals a close relationship between altered E/I patterns, cognition and genetics.

Beta Spectral Power during Passive Listening in Preschool Children with Specific Language Impairment

Introduction: Children with specific language impairment (SLI) have difficulties in different speech and language domains. Electrophysiological studies have documented that auditory processing in children with SLI is atypical and probably caused by delayed and abnormal auditory maturation. During the resting state, or different auditory tasks, children with SLI show low or high beta spectral power, which could be a clinical correlate for investigating brain rhythms. Methods: The aim of this study was to examine the electrophysiological cortical activity of the beta rhythm while listening to words and nonwords in children with SLI in comparison to typical development (TD) children. The participants were 50 children with SLI, aged 4 and 5 years, and 50 age matched TD children. The children were divided into two subgroups according to age: (1) children 4 years of age; (2) children 5 years of age. Results: The older group differed from the younger group in beta auditory processing, with increased values of beta spectral power in the right frontal, temporal, and parietal regions. In addition, children with SLI have higher beta spectral power than TD children in the bilateral temporal regions. Conclusion: Complex beta auditory activation in TD and SLI children indicates the presence of early changes in functional brain connectivity.

Pain symptoms are associated with two-point discrimination threshold in patients with temporomandibular disorders.

This study aimed to explore the associations of orofacial two-point discrimination (2-PD) test result with pain symptoms and psychological factors in patients with Temporomandibular Disorders (TMDs). 193 patients with TMDs were included in this study. Patients' demographics, pain intensity, and psychological status were recorded. The 2-PDs in the bilateral temporal, zygomatic, mandibular, and temporomandibular joint (TMJ) regions of the patients were measured. Statistical analyses were conducted to observe the associations between variables. For Pain-related TMDs (PT) patients, Monthly Visual Analogue Scale (VAS-M) and Current Analogue Scale (VAS-C) were correlated with TMJ, zygomatic and temporal 2-PDs. Patients with PT tended to have higher TMJ 2-PDs[Right: β = 1.827mm, 95%CI(0.107, 3.548), P = 0.038], zygomatic 2-PDs[Right: β = 1.696mm, 95%CI(0.344, 3.048), P = 0.014], temporal 2-PDs[Left: β = 2.138mm, 95%CI(0.127, 4.149), P = 0.037; Right: β = 1.893mm, 95%CI(0.011, 3.775), P = 0.049]. Associations were also observed between VAS-C and TMJ 2-PDs[Left: β = 0.780, 95%CI(0.190, 1.370), P = 0.01; Right: β = 0.885, 95%CI(0.406, 1.364), P = 0.001], Zygomatic 2-PDs[Right: β = 0.555, 95%CI(0.172, 0.938), P = 0.005]; VAS-M and TMJ 2-PDs[Left: β = 0.812, 95%CI(0.313, 1.311), P = 0.002; Right: β = 0.567, 95%CI(0.152, 0.983), P = 0.008], zygomatic 2-PDs[Left: β = 0.405, 95%CI(0.075, 0.735), P = 0.016; Right: β = 0.545, 95%CI(0.221, 0.870), P = 0.001], and temporal 2-PDs [Left: β = 0.741, 95%CI(0.258, 1.224), P = 0.003; Right: β = 0.519, 95%CI(0.063, 0.975), P = 0.026]. TMJ, zygomatic, and temporal 2-PDs were significantly associated with PT and pain intensity. Age, gender and psychological factors were not associated with orofacial 2-PDs. PT patients exhibited weaker tactile acuity compared to Non-PT patients. Further discussion on the underlying mechanism is needed. Orofacial tactile acuity of TMDs patients was associated with their pain symptoms, which researchers should take account into when performing 2-PD tests for TMDs patients. The 2-PD test can be considered as a potential tool along with the current procedures for the differentiations of PT and Non-PT.

Perisylvian and Hippocampal Anomalies in Individuals With Pathogenic GRIN2A Variants.

Pathogenic variants in GRIN2A are associated with a spectrum of epilepsy-aphasia syndromes (EASs). Seizures as well as speech and language disorders occur frequently but vary widely in severity, both between individuals and across the life span. The link between this phenotypic spectrum and brain characteristics is unknown. Specifically, altered brain networks at the root of speech and language deficits remain to be identified. Patients with pathogenic variants in GRIN2A offer an opportunity to interrogate the impact of glutamate receptor dysfunction on brain development. We characterized brain anomalies in individuals with pathogenic GRIN2A variants and EASs, hypothesizing alterations in perisylvian speech-language regions and the striatum. We compared structural MRI data from 10 individuals (3 children and 7 adults, 3 female) with pathogenic GRIN2A variants with data from age-matched controls (N = 51 and N = 203 in a secondary analysis). We examined cortical thickness and volume in 4 a priori hypothesized speech and language regions (inferior frontal, precentral, supramarginal, and superior temporal) and across the whole brain. Subcortical structures (hippocampus, basal ganglia, thalamus) and the corpus callosum were also compared. Individuals with pathogenic GRIN2A variants showed increased thickness and volume in the posterior part of Broca's area (inferior frontal gyrus, pars opercularis). For thickness, the effects were bilateral but more pronounced in the left (large effect size, η2 = 0.37) than the right (η2 = 0.12) hemisphere. Both volume and thickness were also higher in the bilateral superior temporal region while the supramarginal region showed increased thickness only. Whole-brain analyses confirmed left-sided thickness increases in Broca's area, with additional increases in the occipital and superior frontal cortices bilaterally. Hippocampal volume was reduced in the left hemisphere. There were no age-dependent effects or corpus callosum group differences. Anomalies in perisylvian regions, with largest differences in Broca's area, suggest an altered development of classical speech-language networks in GRIN2A-related EAS. Left hippocampal reduction suggests a role for this structure in early speech and language development and is consistent with GRIN2A gene expression in that region. Overall, elucidating the neural correlates of EAS provides insights into the impact of GRIN2A dysfunction, opening avenues for targeted intervention in developmental syndromes with compromised speech-language development.

Comparison of the Efficacy of Two Different Local Anesthesia Techniques for Mesotherapy in Temporal Region Alopecia.

Introduction Mesotherapy is a wide range of minimally invasive injections. In mesotherapy, a mixture of various tonics is injected into the skin. These include plant extracts, various medications, vitamins, enzymes, hormones, growth factors, and other factors that will help treat alopecia. Most commonly, a mixture of platelet-rich plasma (PRP) and vitamins is used. In mesotherapy treatment for hair regrowth in the temporal region, zygomaticotemporal nerve blocks, supratrochlear nerve blocks, and supraorbital nerve blocks are given. The zygomaticotemporal nerve, supraorbital nerve, and supratrochlear nerve are the branches of the trigeminal nerve. They provide sensation on the lateral side of the forehead, which is the temple region. Methods A sample size of 100 people was taken for the study who were undergoing mesotherapy in the bilateral temporal region for alopecia. Each group had 50 subjects: group I was given supratrochlear, supraorbital, and zygomaticotemporal nerve blocks as local anesthesia techniques, and group II was given supratrochlear and supraorbital nerve blocks. PRP was injected using an insulin syringe. Pain was assessed using a visual analog scale (VAS). Results During the procedure, a mean VASof 1 and 3 wasobserved in groups I and II, respectively, during the procedure (p-value0.023). A mean VASof 3 and 5 was observed in groups I and II, respectively, after three hours (p-value 0.000). This shows a significant difference in the pain experienced by the subjects between the groups. Conclusion This study proves that the zygomaticotemporal nerve, used along with supratrochlear and supraorbital nerve blocks, is better at producing analgesia and reducing pain.

Altered perivascular spaces in subcortical white matter in Parkinson’s disease patients with levodopa-induced dyskinesia

Dilated perivascular spaces (PVS) have emerged as a pathological hallmark in various neurological conditions, including Parkinson’s disease (PD). Levodopa-induced dyskinesia (LID), an intractable motor complication of PD, remains enigmatic regarding the distribution patterns of PVS. Our objective was to scrutinize the percent PVS (pPVS) changes within PD patients with LID (PD-LID). In total, 132 individuals were enrolled, including PD-LID (n = 42), PD patients without LID (PD-nLID, n = 45), and healthy controls (HCs, n = 45). Employing an automated approach for PVS quantification based on structural magnetic resonance imaging, we comprehensively evaluated total pPVS in subcortical white matter globally and regionally. A significant increase in global pPVS was observed in PD patients versus HCs, particularly evident in PD-LID relative to HCs. Within the PD-LID group, elevated pPVS was discerned in the right inferior frontal gyrus region (rIFG) (pars opercularis), contrasting with PD-nLID and HCs. Moreover, PD patients exhibited increased pPVS in bilateral superior temporal regions compared to HCs. Notably, pPVS in the rIFG positively correlated with dyskinetic symptoms and could well identify LID. Our findings unveiled PVS alternations in subcortical white matter in PD-LID at both global and regional levels, highlighting the increased pPVS in rIFG as a prospective imaging marker for LID.

Pure amnestic seizure: A clinico-intracranial EEG study.

Enduring anterograde amnesia is caused by lesions in bilateral mesial temporal lobes. However, whether transient dysfunction of bilateral mesial temporal regions induces reversible amnesia has not been proven. We investigated this association in patients with epilepsy and analyzed the electroclinical correlation during pure amnestic seizures (PAS). PAS are defined as seizures with anterograde amnesia as the only ictal manifestation, accompanied by preserved responsiveness and other cognitive functions. We retrospectively searched our intracranial EEG database to find PAS. Pure ictal amnesia was confirmed by immediate and comprehensive ictal examinations. Among 401 patients who underwent intracranial EEG recording, three patients with temporal lobe epilepsy (TLE) manifesting PAS were identified. The patients talked and behaved normally during seizure but did not remember the episodes afterwards. Ictal discharges were confined to bilateral mesial temporal regions, with no or mild involvement of surrounding structures. Spread of low-voltage fast activities to bilateral mesial temporal regions corresponded to onset of ictal anterograde amnesia. Two patients underwent unilateral mesial temporal resection and became seizure-free with improvement in cognitive functions. PAS is a rare ictal semiology in TLE. Bilateral mesial temporal regions that play a critical role in memory encoding are presumably the symptomatogenic zones for PAS.

Brain gray matter morphometry relates to onset age of bilingualism and theory of mind in young and older adults

Lifelong bilingualism may result in neural reserve against decline not only in the general cognitive domain, but also in social cognitive functioning. In this study, we show the brain structural correlates that are associated with second language age of acquisition (L2AoA) and theory of mind (the ability to reason about mental states) in normal aging. Participants were bilingual adults (46 young, 50 older) who completed a theory-of-mind task battery, a language background questionnaire, and an anatomical MRI scan to obtain cortical morphometric features (i.e., gray matter volume, thickness, and surface area). Findings indicated a theory-of-mind decline in older adults compared to young adults, controlling for education and general cognition. Importantly, earlier L2AoA and better theory-of-mind performance were associated with larger volume, higher thickness, and larger surface area in the bilateral temporal, medial temporal, superior parietal, and prefrontal brain regions. These regions are likely to be involved in mental representations, language, and cognitive control. The morphometric association with L2AoA in young and older adults were comparable, but its association with theory of mind was stronger in older adults than young adults. The results demonstrate that early bilingual acquisition may provide protective benefits to intact theory-of-mind abilities against normal age-related declines.

Penalized canonical correlation analysis reveals a relationship between temperament traits and brain oscillations during mind wandering.

There has been a growing interest in studying brain activity under naturalistic conditions. However, the relationship between individual differences in ongoing brain activity and psychological characteristics is not well understood. We investigated this connection, focusing on the association between oscillatory activity in the brain and individually characteristic dispositional traits. Given the variability of unconstrained resting states among individuals, we devised a paradigm that could harmonize the state of mind across all participants. We constructed task contrasts that included focused attention (FA), self-centered future planning, and rumination on anxious thoughts triggered by visual imagery. Magnetoencephalography was recorded from 28 participants under these 3 conditions for a duration of 16min. The oscillatory power in the alpha and beta bands was converted into spatial contrast maps, representing the difference in brain oscillation power between the two conditions. We performed permutation cluster tests on these spatial contrast maps. Additionally, we applied penalized canonical correlation analysis (CCA) to study the relationship between brain oscillation patterns and behavioral traits. The data revealed that the FA condition, as compared to the other conditions, was associated with higher alpha and beta power in the temporal areas of the left hemisphere and lower alpha and beta power in the parietal areas of the right hemisphere. Interestingly, the penalized CCA indicated that behavioral inhibition was positively correlated, whereas anxiety was negatively correlated, with a pattern of high oscillatory power in the bilateral precuneus and low power in the bilateral temporal regions. This unique association was found in the anxious-thoughts condition when contrasted with the focused-attention condition. Our findings suggest individual temperament traits significantly affect brain engagement in naturalistic conditions. This research underscores the importance of considering individual traits in neuroscience and offers an effective method for analyzing brain activity and psychological differences.

The MAPT P.G324L and P.A406G mutations are associated with progressive supranuclear palsy with atypical features

IntroductionProgressive supranuclear palsy (PSP) is an atypical parkinsonism caused by the intracerebral aggregation of the microtubule-associated protein tau (MAPT) which is encoded by MAPT gene. Although PSP is a sporadic disease, MAPT mutations have been reported in rare cases. MethodsAmong 190 patients with PSP who were recruited by the Neurodegenerative Research Group at Mayo Clinic during 2009–2023, we identified two patients who fulfilled diagnostic criteria for PSP-Richardson's syndrome (PSP-RS) and harbor novel MAPT mutations. To better investigate the potential effects of these mutations, we compared the clinical, and neuroimaging characteristics of these two patients to 20 randomly selected patients with PSP-RS without a MAPT mutation. ResultsMAPT c.1024G > A, p. Glu342Lys, and MAPT c.1217 G > A, p. Arg406Gln mutations were found in 2 men who developed PSP-RS with atypical features at the ages of 60 and 62 years, respectively. Glu342Lys mutation was associated with features resembling alpha-synucleinopathies (autonomic dysfunction, dream enactment behavior), while both mutations were associated with features suggestive of Alzheimer's disease with poorer performance on tests of episodic memory. Comparison of 18F-flortaucipir uptake between the two MAPT mutation cases with 20 patients without a mutation revealed increased signal on flortaucipir-PET in bilateral medial temporal lobe regions (amygdala, entorhinal cortices, hippocampus, parahippocampus) but not in PSP-related regions (globus pallidum, midbrain, superior frontal cortex and dentate nucleus of the cerebellum). ConclusionGlu342Lys and Arg406Gln mutations appear to modify the PSP-RS phenotype by targeting the medial temporal lobe regions resulting in more memory loss and greater flortaucipir uptake.

Exploring gray matter volume atrophy associations with hearing in the UK Biobank

AbstractBackgroundHearing impairment was recently recognized as a modifiable risk factor for dementia. Theories to explain this relationship propose that hearing impairment results in reduced sensory input across the brain, which negatively affects brain structure. Therefore, large exploratory studies are needed to examine potential relationships between hearing and brain volume.Method2,000 participants (age = 63±7 years, 50% female) from the UK Biobank were include in this study. Voxelwise multiple regression models examined the association between hearing and baseline MRI gray matter volume. Hearing was assessed using a speech‐in‐noise task, with positive scores reflecting poorer hearing. Interactions between hearing and sex on brain volume were also explored. Covariates included age, sex (except in model with sex interaction), socioeconomic status, and total intracranial volume. Given the exploratory aim of the analysis, a threshold of p<0.001 was used.ResultThe multiple regression model results showed that poorer hearing is associated with lower gray matter volume in bilateral temporal auditory regions (Heschl’s gyrus, superior temporal gyrus) and left amygdala. While hearing scores did not significantly differ by sex, there were significant hearing‐by‐sex interactions. In women, poorer hearing was associated with lower volume in bilateral auditory regions. In men, poorer hearing was associated with lower volume in right hippocampus and higher volume in posterior cingulate cortex.ConclusionThis study sought to address a major gap in the current literature and explored voxelwise associations between hearing and brain volume in a large sample. The results show that poorer hearing is associated with lower brain volume in lateral and medial temporal regions, which differed by sex. Poorer hearing in women was associated with lower volume in auditory regions, while in men, poorer hearing was associated with lower volume in regions similarly affected by Alzheimer’s disease and dementia. Together, these data provide support for a potential mechanistic explanation for the association between hearing loss and dementia through increased brain atrophy.

Acute myelomonoblastic leukemia in children, the particularities of extramedullary infiltration based on a clinical case

Childhood acute myeloidleukemia (AML) represents approximately 5% of childhood malignancies and 15% to 25% of pediatric acute leukemia. The extramedullary manifestation of infiltrating clonal blast populations in a variety of organs and tissues in acute myeloid leukemia (AML) is defined as a distinct entity in the 2016 WHO classification of myeloid neoplasms, myeloid sarcoma The rate of complete remission after induction chemotherapy was lower in patients with extramedullary infiltration, overall survival and event-free survival were not different between patients with and without extramedullary infiltration. Purpose of the study: Presentation of a clinical case of ALM type M4 with the presence of an extramedullary infiltrate in the tissue of the central nervous system in children. Materials and methods: The clinical, paraclinical, imaging data of the patient were studied in parallel with the specialized literature on similar cases. Results: Boy, 5 years old, goes to the doctor with accusations of bilateral palpebral edema, bilateral temporal region edema and bilateral exophthalmos , more pronounced on the left. In the general analysis of the blood: - Hemoglobin - 89 g/l , Leukocytes - 7.2 x 10^9/l; unsegmented neutrophil - 1%; segmented - 18%; lymphocytes - 44%; monocytes - 20%; blast cells - 16%; Platelets - 70 x 10^9/l;VSH - 44 mm/h. During the physical examination: the peripheral lymph nodes are palpable. No signs of central nervous system damage. It is supposed the diagnosis: Acute myeloid leukemia, sarcoma, or neuroblastoma. A medullary puncture: moderately cellular marrow was determined, with blastcells 15.2%. Morphologically, it is more similar to acute myelo-monoblastic leukemia FAB-M4. Computerized Tomography-multiple, hyperdense pathological foci, with localization with inand bilateral extraorbital, associated with exophthalmos. The formation from the sphenoid sinus extends to the nasopharynx , through the pterygopalatine fossa, with narrowing of the lumen and mass effect on the palatine tonsils. Immunophenotyping: CD45-/+ SS low 8% population, CD36+ 6%CD64+ monoblasts 8%, Promonocytes /monocytes – (CD64+/CD14+) 25%.He underwent treatment according to the AML BFM 2004 program with numerous complications, andcranial radiotherapy. At the moment, the child is in morphological remission. Conclusions. The differential diagnosis of hyperdense intracranial masses may include neuroblastoma, meningioma, lymphoma, metastases, or sarcomas. Correct and early diagnosis and initiation of specific treatment are essential to increase the survival rate in cases of acute leukemia in children.