Functional ear (a)symmetry in brainstem neural activity relevant to encoding of voice pitch: a precursor for hemispheric specialization?

Pitch processing is lateralized to the right hemisphere; linguistic pitch is further mediated by left cortical areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch depending on linguistic status. Brainstem frequency-following responses (FFRs) were elicited by monaural stimulation of the left and right ear of 15 native speakers of Mandarin Chinese using two synthetic speech stimuli that differ in linguistic status of tone. One represented a native lexical tone (Tone 2: T2); the other, T2′, a nonnative variant in which the pitch contour was a mirror image of T2 with the same starting and ending frequencies. Two 40-ms portions of f₀ contours were selected in order to compare two regions (R1, early; R2 late) differing in pitch acceleration rate and perceptual saliency. In R2, linguistic status effects revealed that T2 exhibited a larger degree of FFR rightward ear asymmetry as reflected in f₀ amplitude relative to T2′. Relative to midline (ear asymmetry = 0), the only ear asymmetry reaching significance was that favoring left ear stimulation elicited by T2′. By left- and right-ear stimulation separately, FFRs elicited by T2 were larger than T2′ in the right ear only. Within T2′, FFRs elicited by the earlier region were larger than the later in both ears. Within T2, no significant differences in FFRS were observed between regions in either ear. Collectively, these findings support the idea that origins of cortical processing preferences for perceptually-salient portions of pitch are rooted in early, preattentive stages of processing in the brainstem.     

Thinking ahead or not? Natural aging and anticipation during reading

Despite growing evidence of young adults neurally pre-activating word features during sentence comprehension, less clear is the degree to which this generalizes to older adults. Using ERPs, we tested for linguistic prediction in younger and older readers by means of indefinite articles (a’s and an’s) preceding more and less probable noun continuations. Although both groups exhibited cloze probability-graded noun N400s, only the young showed significant article effects, indicating probabilistic sensitivity to the phonology of anticipated upcoming nouns. Additionally, both age groups exhibited prolonged increased frontal positivities to less probable nouns, although in older adults this effect was prominent only in a subset with high verbal fluency (VF). This ERP positivity to contextual constraint violations offers additional support for prediction in the young. For high VF older adults, the positivity may indicate they, too, engage in some form of linguistic pre-processing when implicitly cued, as may have occurred via the articles.     

A brief review on the use of functional near-infrared spectroscopy (fNIRS) for language imaging studies in human newborns and adults

Upon stimulation, real time maps of cortical hemodynamic responses can be obtained by non-invasive functional near-infrared spectroscopy (fNIRS) which measures changes in oxygenated and deoxygenated hemoglobin after positioning multiple sources and detectors over the human scalp. The current commercially available transportable fNIRS systems have a time resolution of 1-10 Hz, a depth sensitivity of about 1.5 cm, and a spatial resolution of about 1 cm. The goal of this brief review is to report infants, children and adults fNIRS language studies. Since 1998, 60 studies have been published on cortical activation in the brain’s classic language areas in children/adults as well as newborns using fNIRS instrumentations of different complexity. In addition, the basic principles of fNIRS including features, strengths, advantages, and limitations are summarized in terms that can be understood even by non specialists. Future prospects of fNIRS in the field of language processing imaging are highlighted.     

精神分裂症肠道微生物与脑影像和临床表征的关系

微生物-肠-脑轴假设在精神分裂症发病机制中的研究受到越来越多的关注。以往研究初步考察了肠道微生物的构成与精神分裂症患者脑影像和临床表征之间的联系,但具体的作用路径尚不明确。当前研究通过总结最新研究进展,并在此基础上提出肠道微生物影响精神分裂症患者大脑结构和功能的机制假设。相关内容对于进一步阐明精神分裂症的病理机制,为将肠道微生物纳入精神分裂症的评估与干预提供理论基础。     

Intimate Partner Violence (IPV) and Neurological Outcomes: A Review for Practitioners

ABSTRACT

Thirty-eight million women will experience intimate partner violence (IPV) during the course of their lifetime. Many of these women will experience brain injuries as a result of IPV and may not seek medical attention. Several types of practitioners who work with IPV survivors consistently, e.g., first responders, advocates, and clinicians, may be unfamiliar with brain functioning, screening, assessment, and treatment. This article reviews the dual traumas of IPV and TBI, the impact on neurological processes and symptomatology, and short and long-term outcomes. Recommendations for screening, intervention, interprofessional collaboration, and research are outlined.     

基因-脑-行为视角下的自伤行为产生机制

自伤是遗传与环境共同作用的结果。目前对于自伤行为的探讨已深入到基因及神经系统层面，基因-脑-行为的综合视角为客观揭示自伤产生机制提供了一条有效途径。本文将在已有研究的基础上，结合分子遗传学和神经生物学的最新成果，对自伤候选基因多态性及其可能的脑机制进行系统阐述，并提出今后应在基因多态性的交互作用及其脑机制、积极环境下自伤行为研究、自伤青少年的追踪研究以及自伤行为的系统性探讨等方面进一步深化。     

Mind matters: A narrative review on affective state-dependency in non-invasive brain stimulation

Variability in findings related to non-invasive brain stimulation (NIBS) have increasingly been described as a result of differences in neurophysiological state. Additionally, there is some evidence suggesting that individual differences in psychological states may correlate with the magnitude and directionality of effects of NIBS on the neural and behavioural level. In this narrative review, it is proposed that the assessment of baseline affective states can quantify non-reductive properties which are not readily accessible to neuroscientific methods. Particularly, affective-related states are theorized to correlate with physiological, behavioural and phenomenological effects of NIBS. While further systematic research is needed, baseline psychological states are suggested to provide a complementary cost-effective source of information for understanding variability in NIBS outcomes. Implementing measures of psychological state may potentially contribute to increasing the sensitivity and specificity of results in experimental and clinical NIBS studies.     

Depression and cognitive sequelae registered within the first year among young Danish TBI survivors

The aim of the study was to determine the proportion of depression and cognitive sequelae among young (15-30 years) Danish TBI survivors referred to interdisciplinary evaluation through a nationwide government-initiated health initiative. The cross-sectional study is based on data from the “Danish register for young adults with acquired brain injury” on TBI survivors included from October 2013 to December 2016. The main measures were Major depression inventory, Trail making test A and B, Fluency, Word learning with selective reminding, Matrix reasoning, Coding and Glasgow outcome scale - extended (GOS-E). During the study period, 131 young TBI survivors were referred to one of five national outpatient clinics. Ninety-six had complete data and of these 14.6% fulfilled the ICD-10 diagnostic criteria for depression and 34.4% had cognitive sequelae. An association was found between depression and cognitive sequelae (p = 0.004). Patients with both depression and cognitive sequelae (n = 10) had a significantly lower mean score on GOS-E (p = 0.0001). Depression and cognitive sequelae were frequent and associated with a poorer global functional outcome among young TBI survivors referred within a year after trauma. This finding and the notion that only 20% of the expected TBI population was referred to this nationwide health initiative indicate an unacknowledged need for interdisciplinary follow-up.     

Traumatic brain injury and adverse psychological effects: Examining a potential pathway to aggressive offending

Contemporary scholarship has demonstrated an association between traumatic brain injury (TBI) during adolescence and aggressive offending. Research, however, has yet to identify any mechanisms linking TBI to subsequent aggressive offending. Consequently, the current study hypothesized that adverse psychological effects is one such pathway. The current study used the Pathways to Desistance data set (n = 416) to examine the pathway of TBI to aggressive offending through adverse psychological effects. The findings of the structural equation model supported the hypothesized association. Specifically, increased exposure to TBI was indirectly associated with aggressive offending through adverse psychological effects. An additional supplemental analysis illustrated that a direct link between TBI and aggressive offending did not exist for the analytical sample. The findings suggested that the neurological disruptions commonly associated with TBI could result in direct increases in negative psychological outcomes and indirect increases in subsequent negative behavioral outcomes.