Diagnosis and rehabilitation attempt of a patient with acquired deep dyslexia

This study presents a patient (JH) suffering from acquired deep dyslexia. According to a cognitive model of reading, JH exhibited a significant impairment in both the phonological and lexical routes to reading. A rehabilitation program was proposed. We decided to focus on the lexical route using a priming paradigm. The written words were associated with a picture and the patient was invited to construct a mental association between the written word and the image. During five sessions, JH was trained to read 50 words. A pre-test, a post-test, and an 8-month follow-up session consisted of reading 140 written words including the 50 trained words. At the post-test, 90% of the trained words were accurately read. At the follow-up session, JH's reading performance for the trained words was still highly accurate at 84%. This strong effect is discussed and ways of increasing the patient's abilities to read are proposed.     

DSM-IV criteria for generalized anxiety disorder in older adults: distinguishing the worried from the well

This study compared 36 older adults with generalized anxiety disorder (GAD), 22 older adults with subsyndromal anxiety symptoms, and 32 normal controls on criteria of the Diagnostic and Statistical Manual of Mental Disorders (4th ed.) for GAD. GAD patients reported more frequent and uncontrollable worry, somewhat different worry content, higher prevalence of most associated symptoms, and more distress or impairment than the subsyndromal group or normal controls. Individuals with subsyndromal anxiety reported more excessive, frequent, and uncontrollable worry than asymptomatic individuals, along with more sleep disturbance, fatigue, and distress or impairment. Results indicate that the key features of late-life GAD are distress and impairment, frequency and uncontrollability of worry, muscle tension, and sleep disturbance and that clinicians treating older adults with GAD should monitor and treat residual symptoms.     

Semantic categorization in the human brain: spatiotemporal dynamics revealed by magnetoencephalography

We examined the cortical representation of semantic categorization using magnetic source imaging in a task that revealed both dissociations among superordinate categories and associations among different base-level concepts within these categories. Around 200 ms after stimulus onset, the spatiotemporal correlation of brain activity elicited by base-level concepts was greater within than across superordinate categories in the right temporal lobe. Unsupervised clustering of data showed similar categorization between 210 and 450 ms mainly in the left hemisphere. This pattern suggests that well-defined semantic categories are represented in spatially distinct, macroscopically separable neural networks, independent of physical stimulus properties. In contrast, a broader, task-required categorization (natural/man-made) was not evident in our data. The perceptual dynamics of the categorization process is initially evident in the extrastriate areas of the right hemisphere; this activation is followed by higher-level activity along the ventral processing stream, implicating primarily the left temporal lobe.     

Enhanced human memory consolidation with post-learning stress: interaction with the degree of arousal at encoding

Abundant evidence indicates that endogenous stress hormones such as epinephrine and corticosterone modulate memory consolidation in animals. We recently provided the first demonstration that an endogenous stress hormone (epinephrine) can enhance human memory consolidation. However, these findings also suggested that post-learning stress hormone activation does not uniformly enhance memory for all recently acquired information; rather, that it interacts with the degree of arousal at initial encoding of material in modulating memory for the material. Here we tested this hypothesis by administering cold pressor stress (CPS) or a control procedure to subjects after they viewed slides of varying emotional content, and assessing memory for the slides 1 wk later. CPS, which significantly elevated salivary cortisol levels, enhanced memory for emotionally arousing slides compared with the controls, but did not affect memory for relatively neutral slides. These findings further support the view that post-learning stress hormone-related activity interacts with arousal at initial encoding to modulate memory consolidation.     

Adolescent Substance Use: Preliminary Examinations of School and Neighborhood Context

In considering the influences of microsystems on adolescent substance use, familial and peer contexts have received the most extensive attention in the research literature. School and neighborhood settings, however, are other developmental contexts that may exert specific influences on adolescent substance use. In many instances, school settings are organized to provide educational services to students who share similar educational abilities and behavioral repertoires. The resulting segregation of students into these settings may result in different school norms for substance use. Similarly, neighborhood resources, including models for substance use and drug sales involvement, may play an important role in adolescent substance use. We briefly review literature examining contextual influences on adolescent substance use, and present results from two preliminary studies examining the contribution of school and neighborhood context to adolescent substance use. In the first investigation, we examine the impact of familial, peer, and school contexts on adolescent substance use. Respondents were 283 students (ages 13 to 18) from regular and special education classrooms in six schools. Although peer and parental contexts were important predictors of substance use, school norms for drug use accounted for variance in adolescent use beyond that explained by peer and parental norms. Data from a second study of 114 adolescents (mean age = 15) examines neighborhood contributions to adolescent substance use. In this sample, neighborhood indices did not contribute to our understanding of adolescent substance use. Implications for prevention are presented.     

自控摄入小剂量酒精影响熟练驾驶行为的实验研究

一个小样本受试者内设计实验,受试者在实验允许的酒精剂量范围内自由选择摄入量。实验安排饮酒前,酒后３０分钟、１１０分钟和１７０分钟四个测试阶段,分别检验受试者在模拟驾驶和实际驾驶两项任务中的认知行为。酒后３０分钟实际驾驶的技能与其他三个测试期相比存在有意义的差别显著性;模拟测试任务中酒后对红、黄两种信号灯的认知反应时之间呈现显著性差别,酒后１１０分钟对黄色信号灯的反应明显延迟。研究提示：受试对酒精感受性的估计是不可靠的,小剂量酒精也能对驾驶行为构成伤害。     

Disgusting clusters: trypophobia as an overgeneralised disease avoidance response

Individuals with trypophobia have an aversion towards clusters of roughly circular shapes, such as those on a sponge or the bubbles on a cup of coffee. It is unclear why the condition exists, given the harmless nature of typical eliciting stimuli. We suggest that aversion to clusters is an evolutionarily prepared response towards a class of stimuli that resemble cues to the presence of parasites and infectious disease. Trypophobia may be an exaggerated and overgeneralised version of this normally adaptive response. Consistent with this explanation, individuals with trypophobia, as well as comparison individuals, reported aversion towards disease-relevant cluster stimuli, but only the trypophobic group reported aversion towards objectively harmless cluster stimuli that had no relevance to disease. For both groups the level of aversion reported was predicted uniquely by a measure of disgust sensitivity. Scaled emotion ratings and open-ended responses revealed that the aversive response was predominantly based on the disease avoidance emotion, disgust. Many open-ended responses also described skin sensations (e.g. skin itching or skin crawling). These findings support the proposal that individuals with trypophobia primarily perceive cluster stimuli as cues to ectoparasites and skin-transmitted pathogens.     

The synergy of working memory and inhibitory control: behavioral, pharmacological and neural functional evidences

Concomitant deficits in working memory and behavioral inhibition in several psychiatric disorders like attention-deficit/hyperactivity disorder, addiction or mania, suggest that common brain mechanisms may underlie their etiologies. Based on the theoretical assumption that a continuum exists between health and mental disorders, we explored the relationship between working memory and inhibition in healthy individuals, through spontaneous inter individual differences in behavior, and tested the hypothesis of a functional link through the fronto-striatal dopaminergic system. Rats were classified into three groups, showing good, intermediate and poor working memory and were compared for their inhibitory abilities. These two functions were simultaneously modulated by a dose-effect of d-amphetamine and in situ hybridization was used to quantify dopaminergic receptor (RD1) mRNAs in prefrontal cortex and striatal areas. A functional relationship between working memory and inhibition abilities was revealed. Both functions were similarly modulated by d-amphetamine according to an inverted-U shaped relationship and depending on initial individual performances. D-amphetamine selectively improved working memory and inhibition of poor and intermediate performers at low doses whereas it impaired both processes in good performers at a higher dose. D1 receptors were less expressed in prelimbic, infralimbic and anterior cingulate cortices of good compared to intermediate and poor performers, whereas no difference was observed between groups in striatal areas. The synergy of working memory and inhibitory abilities, observed in both healthy and psychiatric populations, may originate from endogenous variability in dopaminergic prefrontal cortex activity. Such findings confirm the validity of a dimensional approach, based on the concept of continuity between health and mental disorders for identifying endophenotypes of mental disorders.     

Visuospatial processing in memory for word location in writing

Two experiments examined how visuospatial processing engaged during text composition intervenes in memory for word location. Experiment 1 showed that in contrast to participants who performed a spatial task concurrently with composing a text, participants who performed a concurrent visual task recalled fewer word locations after the composition. Consequently, it is hypothesized that writers process the written text in order to visually represent its physical layout, and that this representation is then used when locating words. Experiment 2 tested this hypothesis by comparing a standard composition condition (with the written trace) with a condition in which the written trace was suppressed during composition, and with a condition without written trace and with added visual noise. Memory for word location only decreased with visual noise, indicating that construction of the visual representation of the text does not rely on the written trace but involves visual working memory.