Frontiers in Human Neuroscience
ISSN / EISSN : 1662-5161 / 1662-5161
Published by: Frontiers Media SA (10.3389)
Total articles ≅ 11,012
Latest articles in this journal
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.858863
Purpose: The ability to hear ourselves speak has been shown to play an important role in the development and maintenance of fluent and coherent speech. Despite this, little is known about the developing speech motor control system throughout childhood, in particular if and how vocal and articulatory control may differ throughout development. A scoping review was undertaken to identify and describe the full range of studies investigating responses to frequency altered auditory feedback in pediatric populations and their contributions to our understanding of the development of auditory feedback control and sensorimotor learning in childhood and adolescence.Method: Relevant studies were identified through a comprehensive search strategy of six academic databases for studies that included (a) real-time perturbation of frequency in auditory input, (b) an analysis of immediate effects on speech, and (c) participants aged 18 years or younger.Results: Twenty-three articles met inclusion criteria. Across studies, there was a wide variety of designs, outcomes and measures used. Manipulations included fundamental frequency (9 studies), formant frequency (12), frequency centroid of fricatives (1), and both fundamental and formant frequencies (1). Study designs included contrasts across childhood, between children and adults, and between typical, pediatric clinical and adult populations. Measures primarily explored acoustic properties of speech responses (latency, magnitude, and variability). Some studies additionally examined the association of these acoustic responses with clinical measures (e.g., stuttering severity and reading ability), and neural measures using electrophysiology and magnetic resonance imaging.Conclusion: Findings indicated that children above 4 years generally compensated in the opposite direction of the manipulation, however, in several cases not as effectively as adults. Overall, results varied greatly due to the broad range of manipulations and designs used, making generalization challenging. Differences found between age groups in the features of the compensatory vocal responses, latency of responses, vocal variability and perceptual abilities, suggest that maturational changes may be occurring in the speech motor control system, affecting the extent to which auditory feedback is used to modify internal sensorimotor representations. Varied findings suggest vocal control develops prior to articulatory control. Future studies with multiple outcome measures, manipulations, and more expansive age ranges are needed to elucidate findings.
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.782579
Gluten ataxia is a rare immune-mediated neurological disorder caused by the ingestion of gluten. The diagnosis is not straightforward as antibodies are present in only up to 38% of patients, but often at lower titers. The symptoms of ataxia may be mild at the onset but lead to permanent damage if remain untreated. It is characterized by damage to the cerebellum however, the pathophysiology of the disease is not clearly understood. The present study investigated the neurochemical profile of vermis and right cerebellum and structural changes in various brain regions of patients with gluten ataxia (n = 6, age range 40–65 years) and compared it with healthy controls (n = 10, 40–55 years). Volumetric 3-D T1 and T1-weighted magnetic resonance imaging (MRI) in the three planes (axial, coronal, and sagittal) of the whole brain and single-voxel 1H- magnetic resonance spectroscopy (MRS) of the vermis and right cerebellum were acquired on 3 T human MR scanner. The metabolite concentrations were estimated using LC Model (6.1–4A) while brain volumes were estimated using the online tool volBrain pipeline and CERES and corrected for partial volumes. The levels of neuro-metabolites (N-acetyl aspartate + N-acetyl aspartate glutamate, glycerophosphocholine + phosphocholine, and total creatine) were found to be significantly lower in vermis, while N-acetyl aspartate + N-acetyl aspartate glutamate and glycerophosphocholine + phosphocholine was lower in cerebellum regions in the patients with gluten ataxia compared to healthy controls. A significant reduction in the white matter of (total brain, cerebellum, and cerebrum); reduction in the volumes of cerebellum lobe (X) and thalamus while lateral ventricles were increased in the patients with gluten ataxia compared to healthy controls. The reduced neuronal metabolites along with structural changes in the brain suggested neuronal degeneration in the patients with gluten ataxia. Our preliminary findings may be useful in understanding the gluten-induced cerebral damage and indicated that MRI and MRS may serve as a non-invasive useful tool in the early diagnosis, thereby enabling better management of these patients.
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.806513
Deep brain stimulation (DBS) of the subthalamic nucleus or the globus pallidus is an established treatment for Parkinson’s disease (PD) that yields a marked and lasting improvement of motor symptoms. Yet, DBS benefit on gait disturbances in PD is still debated and can be a source of dissatisfaction and poor quality of life. Gait disturbances in PD encompass a variety of clinical manifestations and rely on different pathophysiological bases. While gait disturbances arising years after DBS surgery can be related to disease progression, early impairment of gait may be secondary to treatable causes and benefits from DBS reprogramming. In this review, we tackle the issue of gait disturbances in PD patients with DBS by discussing their neurophysiological basis, providing a detailed clinical characterization, and proposing a pragmatic programming approach to support their management.
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.810046
Introduction: Preoperative neurocognitive disorder (preO-NCD) is a common condition affecting 14–51. 7% of the elderly population. General anesthesia has already been associated with the one-year post-operative neurocognitive disorder (PostO-NCD), specifically, a deficit in executive function, measured by the Trail Making Test B (TMT-B), but its long-term effects on cognitive function have not been investigated. We aimed to detect preO-NCD prevalence in patients scheduled for cardiac surgery and further investigate the possible role of previous general anesthesia (pGA) in general preoperative cognitive status [measured via the Montreal Cognitive Assessment (MoCA)] and/or in executive functioning (measured via TMT-B).Methods: In this observational, prospective study, 151 adult patients scheduled for elective cardiac surgery underwent MoCA and TMT-B. Data on age, education, pGA, comorbidities, and laboratory results were collected.Results: We discovered a general cognitive function impairment of 79.5% and an executive function impairment of 22%. Aging is associated with an increased likelihood (OR 2.99, p = 0.047) and education with a decreased likelihood (OR 0.35, p = 0.0045) of general cognitive impairment, but only education was significantly associated with a decreased likelihood (OR 0.22, p = 0.021) of executive function impairment. While pGA did not significantly affect preO-NCD, a noteworthy interaction between aging and pGA was found, resulting in a synergistic effect, increasing the likelihood of executive function impairment (OR 9.740, p = 0.0174).Conclusion: We found a high prevalence of preO-NCD in patients scheduled for cardiac surgery. General cognitive function impairment is highly associated with advancing age (not pGA). However, older patients with at least one pGA appeared to be at an increased risk of preO-NCD, especially executive function impairment, suggesting that TMT-B should be associated with MoCA in the preoperative cognitive evaluation in this population.
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.866256
Musical transposing is highly demanding of working memory, as it involves mentally converting notes from one musical key (i.e., pitch scale) to another key for singing or instrumental performance. Because musical transposing involves mental adjustment of notes up or down by a specific amount, it may share cognitive elements with arithmetical operations of addition and subtraction. We compared brain activity during high and low working memory load conditions of musical transposing versus math calculations in classically trained musicians. Magnetoencephalography (MEG) was sensitive to differences of task and working memory load. Frontal-occipital connections were highly active during transposing, but not during math calculations. Right motor and premotor regions were highly active in the more difficult condition of the transposing task. Multiple frontal lobe regions were highly active across tasks, including the left medial frontal area during both transposing and calculation tasks but the right medial frontal area only during calculations. In the more difficult calculation condition, right temporal regions were highly active. In coherence analyses and neural synchrony analyses, several similarities were seen across calculation tasks; however, latency analyses were sensitive to differences in task complexity across the calculation tasks due to the high temporal resolution of MEG. MEG can be used to examine musical cognition and the neural consequences of music training. Further systematic study of brain activity during high versus low memory load conditions of music and other cognitive tasks is needed to illuminate the neural bases of enhanced working memory ability in musicians as compared to non-musicians.
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.923816
Editorial on the Research TopicNeural Mechanisms of Perceptual-Cognitive Expertise in Elite Performers Perception of sensory information and accompanying cognitive processing are crucial for human interactions with the environment. Elite performers in a number of human endeavors such as athletics, piloting, and surgery are exposed to extremely challenging environmental conditions resulting in the development of exceptional perceptual-cognitive skills. Although it is unknown if these abilities are primary, or are secondary to training and experience, when compared to non-experts they are superior. These enhanced abilities include greater sensitivity and reaction to visual and auditory stimuli, more rapid decision making and faster initiation of motor responses. The increased interest in, and the study of, sports and high-performance activities have enabled the development of an ever-increasing number of tools and techniques to study, quantify, evaluate, and potentially train these skills. With this approach, elite human performance can be studied not only holistically, but also by examining the contribution of each portion of the sensory-motor pathway to decision making and action. In addition to the sensory organs, the central nervous system is integral to this process, and with increasing skill and expertise, structural and functional reorganization is noted within the central nervous system. Our ability to measure these changes provides scientists and clinicians the information necessary to identify targets and the methods to optimize training for maximal performance. The Frontiers Research Topic entitled “Neural Mechanisms of Perceptual-Cognitive Expertise in Elite Performers” is aimed at further exploring the mechanisms and processes that are responsible for perceptual-cognitive expertise in elite performers. Across the seven articles there are a diverse group of reports—ranging from the specific use of auditory stimulation to increase arousal, to broader reports involving surgeons, athletes, and eGamers. The articles in this Research Topic cover three themes. Two of the articles evaluate the role of auditory stimulation to enhance performance in Badminton and Cycling. A second set of articles look at the role of oculomotor learning and behavior in video gamers and bowling, respectively. The final set of three articles review and evaluate models by which the visual-cognitive system can be trained and enhanced through theoretical and experimental perspectives in surgeons, ice hockey, and motorsport athletes. The article, “Music Augmented With Isochronic Auditory Beats or Vibrotactile Stimulation Does Not Affect Subsequent Ergometer Cycling Performance: A Pilot Study” by Fry et al. evaluates two commercially available methods and a self-selected music approach, to quantify ergogenic effects on six male and five female cyclists. The authors evaluated a variety of measurable outcomes including power output as well as felt arousal and feeling scores. The authors found no significant difference between the methods. A second article addressing auditory stimulation entitled “Auditory Information Accelerates the Visuomotor Reaction Speed of Elite Badminton Players in Multisensory Environments,” by Hülsdünker et al. presents results of a comparison between monosensory and multisensory cues in 19 elite badminton athletes. The authors recorded visual and auditory sequences on a live badminton court and then isolated one from the other. These stimuli were then presented in a lab-based reaction test where athletes responded to monosensory (vision or sound) or multisensory (audio-visual) stimulation while brain activity was recorded using EEG. They find that multisensory stimuli lead to the fastest reaction times, followed by mono auditory, then mono visual stimuli. Faster reactions were further paralleled by lower latencies of visual and auditory-evoked potentials. Their results emphasize the contribution of auditory information to elite athlete performance in multisensory environments and suggest that realistic auditory stimulation may be a promising target for training in sports. The next set of papers consider oculomotor behavior and motor learning in sports. In the publication “Oculomotor Behavior Predict Professional Cricket Batting and Bowling Performance” by Murray et al., the authors study 59 male T20 professional cricket athletes. The authors evaluated several measures of oculomotor movement using eye-tracking tests and compared these through multiple regression analyses to cricket performance variables. The results demonstrated predictive relationships between the eye tracking metrics and batting statistics, supporting previously published literature regarding the use of eye-tracking in sports performance evaluation. A second article addressing oculomotor control, entitled “Long-Term Motor Learning in the “Wild” With High Volume Video Game Data” was authored by Listman et al. While most previously published studies in this area are limited by small sample sizes and performed over a short period of study, this study employed a very large sample (7,174 subjects) over a period of several months. The authors found improvements in performance accuracy (modest) as well as motor acuity (considerable). The greatest improvements in motor acuity were noted with an hour of practice in ecologically valid conditions, with 90% of the learning benefit after 30 min of practice per day. These results provide a proof-of-concept for training in ecologically valid settings for longer time scales than are currently typically studied and reported. In a third study addressing oculomotor control, entitled “Neuromonitoring Correlates of Expertise Level in Surgical Performers: A Systematic Review” Hannah et al. review the question of how to...
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.803163
Using fMRI, we investigated how right temporal lobe gliomas affecting the posterior superior temporal sulcus alter neural processing observed during speech perception and production tasks. Behavioural language testing showed that three pre-operative neurosurgical patients with grade 2, grade 3 or grade 4 tumours had the same pattern of mild language impairment in the domains of object naming and written word comprehension. When matching heard words for semantic relatedness (a speech perception task), these patients showed under-activation in the tumour infiltrated right superior temporal lobe compared to 61 neurotypical participants and 16 patients with tumours that preserved the right postero-superior temporal lobe, with enhanced activation within the (tumour-free) contralateral left superior temporal lobe. In contrast, when correctly naming objects (a speech production task), the patients with right postero-superior temporal lobe tumours showed higher activation than both control groups in the same right postero-superior temporal lobe region that was under-activated during auditory semantic matching. The task dependent pattern of under-activation during the auditory speech task and over-activation during object naming was also observed in eight stroke patients with right hemisphere infarcts that affected the right postero-superior temporal lobe compared to eight stroke patients with right hemisphere infarcts that spared it. These task-specific and site-specific cross-pathology effects highlight the importance of the right temporal lobe for language processing and motivate further study of how right temporal lobe tumours affect language performance and neural reorganisation. These findings may have important implications for surgical management of these patients, as knowledge of the regions showing functional reorganisation may help to avoid their inadvertent damage during neurosurgery.
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.845505
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.867055
Introduction: Parkinson’s disease (PD) patients have a significantly higher risk of developing dementia in later disease stages, leading to severe impairments in quality of life and self-functioning. Questions remain on how deep brain stimulation (DBS) affects cognition, and whether we can individualize therapy and reduce the risk for adverse cognitive effects. Our aim in this systematic review is to assess the current knowledge in the field and determine if the findings could influence clinical practice.Methods: We have conducted a systematic review according to PRISMA guidelines through MEDLINE and Embase databases, with studies being selected for inclusion via a set inclusion and exclusion criteria.Results: Sixty-seven studies were included in this systematic review according to the selected criteria. This includes 6 meta-analyses, 18 randomized controlled trials, 17 controlled clinical trials, and 26 observational studies with no control arms. The total number of PD patients encompassed in the studies cited in this review is 3677, not including the meta-analyses.Conclusion: Cognitive function in PD patients can deteriorate, in most cases mildly, but still impactful to the quality of life. The strongest evidence is present for deterioration in verbal fluency, while inconclusive evidence is still present for executive function, memory, attention and processing speed. Global cognition does not appear to be significantly impacted by DBS, especially if cognitive screening is performed prior to the procedure, as lower baseline cognitive function is connected to poor outcomes. Further randomized controlled studies are required to increase the level of evidence, especially in the case of globus pallidus internus DBS, pedunculopontine nucleus DBS, and the ventral intermediate nucleus of thalamus DBS, and more long-term studies are required for all respective targets.
Frontiers in Human Neuroscience, Volume 16; https://doi.org/10.3389/fnhum.2022.811550
The use of transcranial Electrical Stimulation (tES) in the modulation of cognitive brain functions to improve neuropsychiatric conditions has extensively increased over the decades. tES techniques have also raised new challenges associated with study design, stimulation protocol, functional specificity, and dose-response relationship. In this paper, we addressed challenges through the emerging methodology to investigate the dose-response relationship of High Definition-transcranial Direct Current Stimulation (HD tDCS), identifying the role of negative valence in tinnitus perception. In light of the neurofunctional testable framework and tES application, hypotheses were formulated to measure clinical and surrogate endpoints. We posited that conscious pairing adequately pleasant stimuli with tinnitus perception results in correction of the loudness misperception and would be reinforced by concurrent active HD-tDCS on the left Dorsolateral Prefrontal Cortex (dlPFC). The dose-response relationship between HD-tDCS specificity and the loudness perception is also modeled. We conducted a double-blind, randomized crossover pilot study with six recruited tinnitus patients. Accrued data was utilized to design a well-controlled adaptive seamless Bayesian dose-response study. The sample size (n = 47, for 90% power and 95% confidence) and optimum interims were anticipated for adaptive decision-making about efficacy, safety, and single session dose parameters. Furthermore, preliminary pilot study results were sufficient to show a significant difference (90% power, 99% confidence) within the longitudinally detected self-report tinnitus loudness between before and under positive emotion induction. This study demonstrated a research methodology used to improve emotion regulation in tinnitus patients. In the projected method, positive emotion induction is essential for promoting functional targeting under HD-tDCS anatomical specificity to indicate the efficacy and facilitate the dose-finding process. The continuous updating of prior knowledge about efficacy and dose during the exploratory stage adapts the anticipated dose-response model. Consequently, the effective dose range to make superiority neuromodulation in correcting loudness misperception of tinnitus will be redefined. Highly effective dose adapts the study to a standard randomized trial and transforms it into the confirmatory stage in which active HD-tDCS protocol is compared with a sham trial (placebo-like). Establishing the HD-tDCS intervention protocols relying on this novel method provides reliable evidence for regulatory agencies to approve or reject the efficacy and safety. Furthermore, this paper supports a technical report for designing multimodality data-driven complementary investigations in emotion regulation, including EEG-driven neuro markers, Stroop-driven attention biases, and neuroimaging-driven brain network dynamics.