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Frontiers in Neurology 2024
PubMed: 38756211
DOI: 10.3389/fneur.2024.1409139 -
Psychiatry Research. Neuroimaging Jul 2024Auditory verbal hallucinations (AVHs) involve perceptions, often voices, in the absence of external stimuli, and rank among the most common symptoms of schizophrenia....
Auditory verbal hallucinations (AVHs) involve perceptions, often voices, in the absence of external stimuli, and rank among the most common symptoms of schizophrenia. Metrical stress evaluation requires determination of the stronger syllable in words, and therefore requires auditory imagery, of interest for investigation of hallucinations in schizophrenia. The current functional magnetic resonance imaging study provides an updated whole-brain network analysis of a previously published study on metrical stress, which showed reduced directed connections between Broca's and Wernicke's regions of interest (ROIs) for hallucinations. Three functional brain networks were extracted, with the language network (LN) showing an earlier and shallower blood-oxygen-level dependent (BOLD) response for hallucinating patients, in the auditory imagery condition only (the reduced activation for hallucinations observed in the original ROI-based results were not specific to the imagery condition). This suggests that hypoactivation of the LN during internal auditory imagery may contribute to the propensity to hallucinate. This accords with cognitive accounts holding that an impaired balance between internal and external linguistic processes (underactivity in networks involved in internal auditory imagery and overactivity in networks involved in speech perception) contributes to our understanding of the biological underpinnings of hallucinations.
Topics: Humans; Hallucinations; Schizophrenia; Magnetic Resonance Imaging; Adult; Male; Female; Imagination; Language; Brain Mapping; Nerve Net; Brain; Auditory Perception
PubMed: 38754348
DOI: 10.1016/j.pscychresns.2024.111824 -
Frontiers in Endocrinology 2024Syndromic autism spectrum conditions (ASC), such as Klinefelter syndrome, also manifest hypogonadism. Compared to the popular Extreme Male Brain theory, the Enhanced... (Review)
Review
Syndromic autism spectrum conditions (ASC), such as Klinefelter syndrome, also manifest hypogonadism. Compared to the popular Extreme Male Brain theory, the Enhanced Perceptual Functioning model explains the connection between ASC, savant traits, and giftedness more seamlessly, and their co-emergence with atypical sexual differentiation. Overexcitability of primary sensory inputs generates a relative enhancement of local to global processing of stimuli, hindering the abstraction of communication signals, in contrast to the extraordinary local information processing skills in some individuals. Weaker inhibitory function through gamma-aminobutyric acid type A (GABA) receptors and the atypicality of synapse formation lead to this difference, and the formation of unique neural circuits that process external information. Additionally, deficiency in monitoring inner sensory information leads to alexithymia (inability to distinguish one's own emotions), which can be caused by hypoactivity of estrogen and oxytocin in the interoceptive neural circuits, comprising the anterior insular and cingulate gyri. These areas are also part of the Salience Network, which switches between the Central Executive Network for external tasks and the Default Mode Network for self-referential mind wandering. Exploring the possibility that estrogen deficiency since early development interrupts GABA shift, causing sensory processing atypicality, it helps to evaluate the co-occurrence of ASC with attention deficit hyperactivity disorder, dyslexia, and schizophrenia based on phenotypic and physiological bases. It also provides clues for understanding the common underpinnings of these neurodevelopmental disorders and gifted populations.
Topics: Humans; Androgens; Estrogens; Autism Spectrum Disorder; Male; Sex Differentiation; Klinefelter Syndrome; Perception; Brain
PubMed: 38752176
DOI: 10.3389/fendo.2024.1343759 -
The Annals of Otology, Rhinology, and... May 2024This study compared the utilization and outcomes of face-to-face (F2F) vestibular support groups and online support communities (OSC) for individuals with vestibular...
OBJECTIVE
This study compared the utilization and outcomes of face-to-face (F2F) vestibular support groups and online support communities (OSC) for individuals with vestibular disorders.
METHODS
We distributed a 31-question anonymous electronic survey through the Vestibular Disorders Association (VeDA) to F2F participants, categorizing user involvement in F2F, OSCs, or both and assessed impact on medical decision-making, psychosocial benefits, and goals achieved.
RESULTS
The F2F cohort consisted of 97 individuals comprising primarily of non-Hispanic White women (mean age = 57 years, SD ± 14 years) with diagnoses including persistent postural-perceptual dizziness (19%), Meniere's disease (15%), and vestibular neuritis (13%). Most participants were diagnosed by an otolaryngologist (65%) and attended F2F meetings monthly or less frequently (78%). The OSC group comprised of 551 individuals, primarily of non-Hispanic White women, but was younger in age (mean age = 50 years, SD ± 13 years). OSC participants notably engaged more, with 36% participating on a daily basis and 32% multiple times a week. F2F participants were older (mean age 57 years vs 50 years, < .001) and more commonly referred by medical professionals (22% F2F vs 6% OSC, < .001). Both groups had similar achieved goals, including hearing from others with the same diagnosis (84% vs 89%, > .05) and similar impact on medical decision-making (75% vs 78%, > .05). More F2F participants reported increased development of coping skills (79% F2F vs 69% OSC, = .037). OSC participants typically found the group via an online search (75%), compared to 51% for F2F. OSC participants had higher daily engagement (36%) compared to F2F (1%).
CONCLUSION
F2F users are older and more commonly referred by medical professionals. Despite less frequent engagement, F2F participants reported similar influences on achieved goals, medical decision-making, and impact on psychosocial benefits. These findings highlight the importance of both F2F and OSC support groups for individuals with vestibular disorders.
PubMed: 38738670
DOI: 10.1177/00034894241241861 -
Journal of Psychosomatic Research Aug 2024Recent neuroscientific models suggest that functional bodily symptoms can be attributed to perceptual dysregulation in the central nervous system. Evidence for this...
Experimental evidence for a robust, transdiagnostic marker in functional disorders: Erroneous sensorimotor processing in functional dizziness and functional movement disorder.
OBJECTIVE
Recent neuroscientific models suggest that functional bodily symptoms can be attributed to perceptual dysregulation in the central nervous system. Evidence for this hypothesis comes from patients with functional dizziness, who exhibit marked sensorimotor processing deficits during eye-head movement planning and execution. Similar findings in eye-head movement planning in patients with irritable bowel syndrome confirmed that these sensorimotor processing deficits represent a shared, transdiagnostic mechanism. We now examine whether erroneous sensorimotor processing is also at play in functional movement disorder.
METHODS
We measured head movements of 10 patients with functional movement disorder (F44.4, ICD-10), 10 patients with functional dizziness (F45.8, ICD-10), and (respectively) 10 healthy controls during an eye-head experiment, where participants performed large gaze shifts under normal, increased, and again normal head moment of inertia. Head oscillations at the end of the gaze shift served as a well-established marker for sensorimotor processing problems. We calculated Bayesian statistics for comparison.
RESULTS
Patients with functional movement disorder (Bayes Factor (BF) = 5.36, BF = 11.16; substantial to strong evidence) as well as patients with functional dizziness (BF = 2.27, BF = 3.56; anecdotal to substantial evidence) showed increased head oscillations compared to healthy controls, indicating marked deficits in planning and executing movement.
CONCLUSION
We replicate earlier experimental findings on erroneous sensorimotor processing in patients with functional dizziness, and show that patients with functional movement disorder show a similar impairment of sensorimotor processing during large gaze shifts. This provides an objectively measurable, transdiagnostic marker for functional disorders, highlighting important implications for diagnosis, treatment, and de-stigmatization.
Topics: Humans; Dizziness; Female; Male; Adult; Middle Aged; Movement Disorders; Head Movements; Eye Movements; Bayes Theorem
PubMed: 38734533
DOI: 10.1016/j.jpsychores.2024.111694 -
Cortex; a Journal Devoted To the Study... Jul 2024Spatial neglect is a common and debilitating disorder after stroke whereby individuals have difficulty reporting, orienting, and/or responding to the contralesional side... (Review)
Review
Spatial neglect is a common and debilitating disorder after stroke whereby individuals have difficulty reporting, orienting, and/or responding to the contralesional side of space. Given the heterogeneity of neglect symptom presentation, various neglect subtypes have been proposed to better characterize the disorder. This review focuses on the distinction between Input neglect (i.e., difficulty perceiving and/or attending to contralesional stimuli) and Output neglect (i.e., difficulty planning and/or executing movements toward contralesional stimuli). Conceptualizations of Input and Output neglect have varied considerably. We provide a novel summary of the terminology, measurement approaches, and neural correlates of these subtypes. A protocol detailing our systematic scoping review strategy is registered on the Open Science Framework (https://osf.io/bvtxf/). For feasibility and greater comparability across studies, we limited our inclusion criteria to tasks focused on visual stimuli and upper-limb movements. A total of 110 articles were included in the review. Subtyping tasks were categorized based on whether they mainly manipulated aspects of the input (i.e., congruence of visual input with motor output, presence of visual input) or the output (i.e., modality, goal, or direction of output) to produce an Input-Output subtype dissociation. We used our review results to identify four main critiques of this literature: 1) lack of consistency/clarity in conceptual models; 2) methodological issues of dissociating Input and Output subtypes; 3) a need for updated neural theories; and 4) barriers to clinical application. We discuss the lessons learned from this subtyping dimension that can be applied to future research on neglect subtype assessment and treatment.
Topics: Humans; Perceptual Disorders; Space Perception; Stroke; Functional Laterality; Visual Perception; Psychomotor Performance
PubMed: 38729033
DOI: 10.1016/j.cortex.2024.04.005 -
PloS One 2024Developmental coordination disorder (DCD) is one of the most prevalent pediatric chronic conditions. Without proper intervention, significant delays in motor skill...
INTRODUCTION
Developmental coordination disorder (DCD) is one of the most prevalent pediatric chronic conditions. Without proper intervention, significant delays in motor skill performance and learning may persist until adulthood. Moderate-to-vigorous physical exercise has been proven to improve motor learning (adaptation and consolidation) in children with or without disorders. However, the effect of a short bout of physical exercise on motor adaptation and consolidation in children with DCD has not been examined. Furthermore, the role of perceptual-motor integration and attention as mediators of learning has not been examined via neuroimaging in this population.
OBJECTIVES
Therefore, the primary aims of this project will be to compare children with and without DCD to (a) examine the effect of acute exercise on motor learning (adaptation and consolidation) while performing a rotational visuo-motor adaptation task (rVMA), and (b) explore cortical activation in the dorsolateral- and ventrolateral-prefrontal cortex areas while learning the rVMA task under rest or post-exercise conditions.
METHODS
One hundred twenty children will be recruited (60 DCD, 60 controls) and within-cohort randomly assigned to either exercise (13-minute shuttle run task) or rest prior to performing the rVMA task. Adaptation and consolidation will be evaluated via two error variables and three retention tests (1h, 24h and 7 days post adaptation). Cortical activation will be registered via functional near-infrared spectroscopy (fNIRS) during the baseline, adaptation, and consolidation.
DISCUSSION
We expect to find exercise benefits on motor learning and attention so that children with DCD profiles will be closer to those of children with typical development. The results of this project will provide further evidence to: (a) better characterize children with DCD for the design of educational materials, and (b) establish acute exercise as a potential intervention to improve motor learning and attention.
Topics: Humans; Motor Skills Disorders; Child; Learning; Exercise; Female; Male; Motor Skills; Brain; Adaptation, Physiological; Adolescent; Exercise Therapy
PubMed: 38722962
DOI: 10.1371/journal.pone.0302242 -
JASA Express Letters May 2024The perceptual boundary between short and long categories depends on speech rate. We investigated the influence of speech rate on perceptual boundaries for short and...
The perceptual boundary between short and long categories depends on speech rate. We investigated the influence of speech rate on perceptual boundaries for short and long vowel and consonant contrasts by Spanish-English bilingual listeners and English monolinguals. Listeners tended to adapt their perceptual boundaries to speech rates, but the strategy differed between groups, especially for consonants. Understanding the factors that influence auditory processing in this population is essential for developing appropriate assessments of auditory comprehension. These findings have implications for the clinical care of older populations whose ability to rely on spectral and/or temporal information in the auditory signal may decline.
Topics: Humans; Multilingualism; Speech Perception; Female; Male; Adult; Phonetics; Young Adult
PubMed: 38717469
DOI: 10.1121/10.0025862 -
Translational Psychiatry May 2024Bi-stable stimuli evoke two distinct perceptual interpretations that alternate and compete for dominance. Bi-stable perception is thought to be driven at least in part...
Bi-stable stimuli evoke two distinct perceptual interpretations that alternate and compete for dominance. Bi-stable perception is thought to be driven at least in part by mutual suppression between distinct neural populations that represent each percept. Abnormal visual perception has been observed among people with psychotic psychopathology (PwPP), and there is evidence to suggest that these visual deficits may depend on impaired neural suppression in the visual cortex. However, it is not yet clear whether bi-stable visual perception is abnormal among PwPP. Here, we examined bi-stable perception in a visual structure-from-motion task using a rotating cylinder illusion in a group of 65 PwPP, 44 first-degree biological relatives, and 43 healthy controls. Data from a 'real switch' task, in which physical depth cues signaled real switches in rotation direction were used to exclude individuals who did not show adequate task performance. In addition, we measured concentrations of neurochemicals, including glutamate, glutamine, and γ-amino butyric acid (GABA), involved in excitatory and inhibitory neurotransmission. These neurochemicals were measured non-invasively in the visual cortex using 7 tesla MR spectroscopy. We found that PwPP and their relatives showed faster bi-stable switch rates than healthy controls. Faster switch rates also correlated with significantly higher psychiatric symptom levels, specifically disorganization, across all participants. However, we did not observe any significant relationships across individuals between neurochemical concentrations and SFM switch rates. Our results are consistent with a reduction in suppressive neural processes during structure-from-motion perception in PwPP, and suggest that genetic liability for psychosis is associated with disrupted bi-stable perception.
Topics: Humans; Male; Female; Adult; Psychotic Disorders; Visual Cortex; Visual Perception; Young Adult; Motion Perception; Magnetic Resonance Spectroscopy; Middle Aged
PubMed: 38714650
DOI: 10.1038/s41398-024-02913-z