White matter associations with spelling performance
AbstractMultiple neurocognitive processes are involved in the highly complex task of producing written words. Yet, little is known about the neural pathways that support spelling in healthy adults. We assessed the associations between performance on a difficult spelling-to-dictation task and microstructural properties of language-related white matter pathways, in a sample of 73 native English-speaking neurotypical adults. Participants completed a diffusion magnetic resonance imaging scan and a cognitive assessment battery. Using constrained spherical deconvolution modeling and probabilistic tractography, we reconstructed d...
Source: Anatomy and Embryology - March 25, 2024 Category: Anatomy Source Type: research

The effect of high-frequency rTMS over left DLPFC and fluid abilities on goal neglect
AbstractGoal neglect refers to when an aspect of task instructions is not utilised due to increased competition between goal representations, an attentional limit theoretically linked to working memory. In an attempt to alleviate goal neglect and to investigate the association between dorsolateral prefrontal cortex (DLPFC)-supported working memory and goal neglect, we used high-frequency repetitive transcranial magnetic stimulation to the left DLPFC whilst participants completed the letter-monitoring task, a measure of goal neglect, and an N3-back task, a working memory task known to be affected by rTMS of the left DLPFC, ...
Source: Anatomy and Embryology - March 22, 2024 Category: Anatomy Source Type: research

White matter structural changes before and after microvascular decompression for hemifacial spasm
AbstractHemifacial spasm (HFS) is a syndrome characterized by involuntary contractions of the facial muscles innervated by the ipsilateral facial nerve. Currently, microvascular decompression (MVD) is an effective treatment for HFS. Diffusion weighted imaging (DWI) is a non-invasive advanced magnetic resonance technique that allows us to reconstruct white matter (WM) virtually based on water diffusion direction. This enables us to model the human brain as a complex network using graph theory. In our study, we recruited 32 patients with HFS and 32 healthy controls to analyze and compare the topological organization of whole...
Source: Anatomy and Embryology - March 19, 2024 Category: Anatomy Source Type: research

Unveiling the neuroanatomy of Josephoartigasia monesi and the evolution of encephalization in caviomorph rodents
AbstractCaviomorph rodents are an exceptional model for studying the effects of ecological factors and size relations on brain evolution. These mammals are not only speciose and ecologically diverse but also present wide body size disparity, especially when considering their fossil relatives. Here, we described the brain anatomy of the largest known rodent,Josephoartigasia monesi, uncovering distinctive features within this species regarding other taxa. Albeit resembling extant pacaranaDinomys branickii,J. monesi stands out due to its longer olfactory tract and well-developed sagittal sinus. Challenging the previous hypoth...
Source: Anatomy and Embryology - March 19, 2024 Category: Anatomy Source Type: research

MRI atlas of the pituitary gland in young female adults
In this study, we aimed at creating maximum probability maps for the anterior and posterior PG in young female adults. We manually delineated the anterior and posterior parts of the pituitary glands in 26 healthy subjects using high-resolution MRI T1 images. A three-step procedure and a cost function-masking approach were employed to optimize spatial normalization for the PG. We generated probabilistic atlases and maximum probability maps, which were subsequently coregistered back to the subjects ’ space and compared to manual delineations. Manual measurements led to a total pituitary volume of 705 ± 88 mm³, with ...
Source: Anatomy and Embryology - March 19, 2024 Category: Anatomy Source Type: research

Aspiration removal of orbitofrontal cortex disrupts cholinergic fibers of passage to anterior cingulate cortex in rhesus macaques
AbstractThe study of anthropoid nonhuman primates has provided valuable insights into frontal cortex function in humans, as these primates share similar frontal anatomical subdivisions (Murray et al.2011). Causal manipulation studies have been instrumental in advancing our understanding of this area. One puzzling finding is that macaques with bilateral aspiration removals of orbitofrontal cortex (OFC) are impaired on tests of cognitive flexibility and emotion regulation, whereas those with bilateral excitotoxic lesions of OFC are not (Rudebeck et al.2013). This discrepancy is attributed to the inadvertent disruption of fib...
Source: Anatomy and Embryology - March 19, 2024 Category: Anatomy Source Type: research

A revision of the dorsal origin of the frontal aslant tract (FAT) in the superior frontal gyrus: a DWI-tractographic study
AbstractThe frontal aslant tract (FAT) is a white matter tract connecting the superior frontal gyrus (SFG) to the inferior frontal gyrus (IFG). Its dorsal origin is identified in humans in the medial wall of the SFG, in the supplementary motor complex (SM-complex). However, empirical observation shows that many FAT fibres appear to originate from the dorsal, rather than medial, portion of the SFG. We quantitatively investigated the actual origin of FAT fibres in the SFG, specifically discriminating between terminations in the medial wall and in the convexity of the SFG. We analysed data from 105 subjects obtained from the ...
Source: Anatomy and Embryology - March 19, 2024 Category: Anatomy Source Type: research

The combination treatment of hypothermia and intranasal insulin ameliorates the structural and functional changes in a rat model of traumatic brain injury
AbstractThe present study aimed to investigate the combination effects of hypothermia (HT) and intranasal insulin (INS) on structural changes of the hippocampus and cognitive impairments in the traumatic brain injury (TBI) rat model. The rats were divided randomly into the following five groups (n = 10): Sham, TBI, TBI with HT treatment for 3 h (TBI + HT), TBI with INS (ten microliters of insulin) treatment daily for 7 days (TBI + INS), and TBI with combining HT and INS (TBI + HT + INS). At the end of the 7th day, the open field and the Morris water maze tests were done for evaluation of anxiety-like ...
Source: Anatomy and Embryology - March 18, 2024 Category: Anatomy Source Type: research

A clinico-anatomical dissection of the magnocellular and parvocellular pathways in a patient with the Riddoch syndrome
This study shows that damage to the anatomical input to V1, i.e., the optic radiations, can result in selective visual deficits that mimic the Riddoch syndrome. The results also highlight the differential susceptibility of the magnocellular and parvocellular visual systems to injury. Overall, this study offers new insights that will improve our understanding of the impact of brain injury and neurosurgery on the visual pathways.AbstractThe Riddoch syndrome, characterised by the ability to perceive, consciously, moving visual stimuli but not static ones, has been associated with lesions of primary visual cortex (V1). We pres...
Source: Anatomy and Embryology - March 16, 2024 Category: Anatomy Source Type: research

Transcriptomic contributions to a modern cytoarchitectonic parcellation of the human cerebral cortex
AbstractTranscriptomic contributions to the anatomical, functional, and network layout of the human cerebral cortex (HCC) have become a major interest in cognitive and systems neuroscience. Here, we tested if transcriptomic differences support a modern, algorithmic cytoarchitectonic parcellation of HCC. Using a data-driven approach, we identified a sparse subset of genes that differentially contributed to the cytoarchitectonic parcellation of HCC. A combined metric of cortical thickness and myelination (CT/M ratio), as well as cell density, correlated with gene expression. Enrichment analyses showed that genes specific to ...
Source: Anatomy and Embryology - March 16, 2024 Category: Anatomy Source Type: research

Rodent maze studies: from following simple rules to complex map learning
AbstractMore than 100  years since the first maze designed for rodent research, researchers now have the choice of a variety of mazes that come in many different shapes and sizes. Still old designs get modified and new designs are introduced to fit new research questions. Yet, which maze is the most optimal to use or wh ich training paradigm should be applied, remains up for debate. In this review, we not only provide a historical overview of maze designs and usages in rodent learning and memory research, but also discuss the possible navigational strategies the animals can use to solve each maze. Furthermore, we s ummari...
Source: Anatomy and Embryology - March 15, 2024 Category: Anatomy Source Type: research

Modulation of intracortical circuits in primary motor cortex during automatic action tendencies
AbstractHumans display automatic action tendencies toward emotional stimuli, showing faster automatic behavior (i.e., approaching a positive stimulus and avoiding a negative stimulus) than regulated behavior (i.e., avoiding a positive stimulus and approaching a negative stimulus). Previous studies have shown that the primary motor cortex is involved in the processing of automatic actions, with higher motor evoked potential amplitudes during automatic behavior elicited by single-pulse transcranial magnetic stimulation. However, it is unknown how intracortical circuits are involved with automatic action tendencies. Here, we ...
Source: Anatomy and Embryology - March 14, 2024 Category: Anatomy Source Type: research

Hayling and stroop tests tap dissociable deficits and network-level neural correlates
This study presents a comparative analysis of the Stroop and Hayling tests aiming to evaluate whether these tests measure the same underlying cognitive functions and to identify the neural correlates of the deficits detected by both tasks. Sixty six stroke survivors and 70 healthy ageing controls completed the Hayling and Stroop tests. Stroke patients were found to exhibit qualitative performance differences across analogous Stroop and Hayling Test metrics intended to tap initiation and inhibition. The Stroop test was found to have high specificity to abnormal performance, but low sensitivity relative to the Hayling Test. ...
Source: Anatomy and Embryology - March 13, 2024 Category: Anatomy Source Type: research

Altered functional-structural coupling may predict Parkinson ’s patient’s depression
AbstractWe aimed to elucidate the neurobiological basis of depression in Parkinson ’s disease and identify potential imaging markers for depression in patients with Parkinson’s disease. We recruited 43 normal controls (NC), 46 depressed Parkinson’s disease patients (DPD) and 56 non-depressed Parkinson’s disease (NDPD). All participants underwent routine T2-weighted, T2Flai r, and resting-state scans on the same 3.0 T magnetic resonance imaging (MRI) scanner at our hospital. Pre-processing includes calculating surface-based Regional Homogeneity (2DReHo) and cortical thickness. Then we defined the correlation coeffi...
Source: Anatomy and Embryology - March 13, 2024 Category: Anatomy Source Type: research

Topological features of functional brain networks and subclinical impulsivity: an investigation in younger and older adults
AbstractImpulsive traits (i.e., the tendency to act without forethought regardless of negative outcomes) are frequently found in healthy populations. When exposed to risk factors, individuals may develop debilitating disorders of impulse control (addiction, substance abuse, gambling) characterized by behavioral and cognitive deficits, eventually leading to huge socioeconomic costs. With the far-reaching aim of preventing the onset of impulsive disorders, it is relevant to investigate the topological organization of functional brain networks associated with impulsivity in sub-clinical populations. Taking advantage of the op...
Source: Anatomy and Embryology - March 6, 2024 Category: Anatomy Source Type: research