Gender Differences in Cognitive and Emotional Adjustment to Traumatic Brain Injury

This study examined gender differences in cognitive and emotional status after traumatic brain injury (TBI) among 262 men and 140 women with TBI referred for neuropsychological evaluations. In this cross-sectional study, cognition was measured in terms of both absolute level of functioning (i.e., raw/standard scores) and estimated decline from premorbid levels expressed as z-deficit scores in the following domains: intelligence [Wechsler Adult Intelligence Scale—Revised (WAIS-R)], memory and attention [Wechsler Memory Scale—Revised (WMS-R)], processing speed (Trails A), and cognitive flexibility (Trails B). Emotional functioning was measured in terms of depression (Beck Depression Inventory) and general emotional distress (Brief Symptom Inventory). Kruskal–Wallis nonparametric one-way ANOVAs indicated that women and men differed significantly on 2 of 8 raw/standard cognitive scores [men demonstrated lower WMS-R General Memory (p < .05) and Trails B scores (p < .0001) and 4 of 8 relative decline scores [women demonstrated more estimated change in VIQ (Verbal IQ) [p < .0001], FSIQ (Full Scale IQ) [p < .01], and Attention (p < .01)]; men demonstrated greater estimated z-decline scores on Trails B (p < .01)]. Women reported significantly higher levels of depression (p < .01), but men endorsed significantly greater general psychological distress (p < .05). Research and assessment recommendations are suggested.     

Problems in Psychiatric Genetic Research: A Reply to Faraone and Biederman

This article examines evidence cited in favor of the operation of genetic factors in attention-deficit hyperactivity disorder (ADHD). Like other psychiatric conditions, a belief in the genetic basis of ADHD is derived from the results of family, twin, and adoption studies. Because family studies are widely believed to be confounded by environmental factors, primary emphasis is placed on twin and adoption studies. ADHD twin studies depend on the validity of the equal environment assumption (EEA), which holds that the environments of identical (MZ) and fraternal (DZ) twins are the same. Here it is argued that however the EEA is defined, it cannot be accepted. Therefore, the greater similarity or concordance of MZ twins when compared to DZ twins is plausibly explained by environmental factors. Adoption studies constitute a third method for investigating the role of genetic factors in ADHD. It is argued that these studies are greatly flawed by factors including non blinded diagnoses and the failure to study the biological relatives of adoptees. After an examination of the total weight of evidence in favor of a genetic basis or predisposition for ADHD, it is concluded that a role for genetic factors is not supported and that future research should be directed toward psychosocial causes     

颅脑肿瘤切除术后硬膜外血肿的原因及预防

浅析颅脑肿瘤切除术后硬膜外血肿形成的原因及预防措施。回顾性分析本科室自2005年7月～2009年7月共计13例脑肿瘤术后硬膜外血肿发生的特点,所有病例血肿均发生于小脑幕上,其中7例位于额部,3例位于颞部,2例位于顶部,1例位于枕部;平均血肿量为(37.3±3.2)ml。脑肿瘤切除术后硬膜外血肿形成机制为多种原因所导致的颅内压及脑脊液动力学改变致硬脑膜与颅骨剥离有关。各环节采取相应预防措施及术后常规复查头颅CT是防治脑肿瘤术后非手术区域硬膜外血肿的关键。     

孤独症谱系障碍者的视觉-空间工作记忆缺陷及脑机制

孤独症谱系障碍(ASD)个体存在视觉-空间工作记忆加工缺陷,主要表现在4个方面,即随认知负荷增大而缺陷加重、工作记忆容量不足、工作记忆加工过程中的注意功能失调和对刺激进行整体组织的能力缺乏。神经机制研究显示,ASD个体存在明显的额-顶工作记忆网络激活异常,以及相关脑区的脑结构、白质连接异常。另外,作为基础性的认知加工过程,ASD个体的视觉-空间工作记忆各加工环节与言语工作记忆、执行功能、社会认知等因素均存在交互影响。纵观目前研究成果,未来研究可从研究手段、机制探究和干预训练三方面入手,着眼于研究方法的生态化和多元化,揭示客体和空间工作记忆的机制分离,并着力开发更具针对性的干预训练模式。     

计算的脑机制研究进展

采用计算任务来探讨脑机制已成为国外研究大脑活动的重要领域。该文阐述了神经心理学和脑成像领域有关计算的脑机制研究。神经心理学及脑损伤的研究结果表明,大脑两侧顶下小叶和左前额叶与计算加工有关。ERP、PET和fMRI脑成像研究结果显示,数字命名与比较、心算、精算和估算等不同计算任务,其所激活的脑部位有所差异,但是大脑两侧顶下小叶和左前额叶可能是计算加工的主要脑部位。由于研究材料、方法和程序的不同,大脑皮层的广泛区域都有可能参与计算加工。     

Imagination and Reality: On the Relations Between Myth, Consciousness, and the Quantum Sea

There often appears to be a striking correspondence between mythic stories and aspects of reality. We will examine the processes of creative imagination within a neurobiological frame and suggest a theory that may explain the functions of myth in relation to the hidden aspects of reality. Myth is peppered with archetypal entities and interactions that operate to reveal hidden processes in reality that are relative to the human condition. The imagery in myths in a sense "sustains the true." That is, mythopoetic imagery keeps the interpretive process in experience closer to the actual nature of reality than the rational faculties operating alone are able to do. Indeed, whereas rationalizing can easily lead us awry, genuine myth rarely does. Explanations of events offered by cultures around the world are frequently couched in terms of mythic themes and events. An important function of myth is to provide a "field of tropes" that in-forms the lived experience of people. This paper focuses especially on those aspects of myth that represent facets of the quantum universe and give us clues as to the relationship between consciousness, symbolism, and reality.     

Neurophysiological marker of inhibition distinguishes language groups on a non-linguistic executive function test

Successful interaction with the environment depends on flexible behaviors which require shifting attention, inhibiting primed responses, ignoring distracting information, and withholding motor responses. These abilities, termed executive function (EF), are believed to be mediated by inhibitory processes in the frontal lobes. Superior performance on EF tests (i.e., faster reaction times (RT), and fewer errors) has been shown in bilinguals compared to monolingual speakers. However, findings are inconsistent, and no study has directly linked this bilingual advantage to frontal lobe inhibitory processes. To clarify this uncertainty, we concomitantly tested neural inhibitory processes and behavioral responses on an EF test in bilinguals and monolinguals. Specifically, we compared English monolinguals (N = 15) to Spanish/English bilinguals (N = 13) on event-related brain potentials (ERP) during a non-linguistic, auditory Go/NoGo task, a task linked to non-motor, cognitive inhibition in monolinguals. Participants responded with a button press on trials in which target tone-pairs (Go trials) were presented and withheld their responses on non-target trials (NoGo trials). Results revealed significantly greater inhibition (i.e., greater mean N2 amplitude) in bilinguals compared to monolinguals during NoGo trials even though both groups performed the task equally well (i.e., withheld a motor response). On Go trials where participants pressed a response button, neither ERPs nor RT distinguished the groups. Additionally, scores on a second language proficiency test (i.e., English in our bilingual group) were positively correlated with N2 amplitude. These findings are the first to directly link this bilingual advantage to a neural correlate of inhibition and to reveal that inhibition in bilinguals is moderated by second language proficiency. Results are discussed in the context of plasticity, and we propose that evaluating bilinguals at varying levels of second-language proficiency may serve as a model of human neuroplasticity.     

Using fMRI to study recovery from acquired dysphasia

We have used functional magnetic resonance imaging (fMRI) to characterize brain activations associated with two distinct language tasks performed by a 28-year-old woman after partial recovery from dysphasia due to a left frontal hemispheric ischemic stroke. MRI showed that her ischemic lesion extended posteriorly from the left inferior frontal to the perisylvian cortex. fMRI scans of both language tasks revealed substantial differences in activation pattern relative to controls. The nature of this difference was task-specific. During performance of a verbal semantic decision task, the patient, in contrast to controls, activated a network of brain areas that excluded the inferior frontal gyrus (in either hemisphere). A second task involving rhyme judgment was designed to place a heavier cognitive load on language production processes and activated the left inferior frontal gyrus (Broca's area) strongly in normal controls. During this task, the most prominent frontal activation in the patient occurred in the right homologue of Broca's area. Subsequent analysis of this data by methods able to deal with responses of changing amplitude revealed additional, less sustained recruitment by the patient of cortex adjacent to the infarct in the region inferior to Broca's area during rhyming. These results suggest that in addition to changes in cognitive strategy, recovery from dysphasia could be mediated by both the preservation of neuronal networks in and around the infarct and the use of homologous regions in the contralateral hemisphere.     

Rapid word identification in pure alexia is lexical but not semantic

Following the notion that patients with pure alexia have access to two distinct reading strategies-letter-by-letter reading and semantic reading-a training program was devised to facilitate reading via semantics in a patient with pure alexia. Training utilized brief stimulus presentations and required category judgments rather than explicit word identification. The training was successful for trained words, but generalized poorly to untrained words. Additional studies involving oral reading of nouns and of functors also resulted in improved reading of trained words. Pseudowords could not be trained to criterion. The results suggest that improved reading can be achieved in pure alexia by pairing rapidly presented words with feedback. Focusing on semantic processing is not essential to this process. It is proposed that the training strengthens connections between the output of visual processing and preexisting orthographic representations.