The myth of the visual word form area

Recent functional imaging studies have referred to a posterior region of the left midfusiform gyrus as the "visual word form area" (VWFA). We review the evidence for this claim and argue that neither the neuropsychological nor neuroimaging data are consistent with a cortical region specialized for visual word form representations. Specifically, there are no reported cases of pure alexia who have deficits limited to visual word form processing and damage limited to the left midfusiform. In addition, we present functional imaging data to demonstrate that the so-called VWFA is activated by normal subjects during tasks that do not engage visual word form processing such as naming colors, naming pictures, reading Braille, repeating auditory words, and making manual action responses to pictures of meaningless objects. If the midfusiform region has a single function that underlies all these tasks, then it does not correspond to visual word form processing. On the other hand, if the region participates in several functions as defined by its interactions with other cortical areas, then identifying the neural system sustaining visual word form representations requires identification of the set of regions involved. We conclude that there is no evidence that visual word form representations are subtended by a single patch of neuronal cortex and it is misleading to label the left midfusiform region as the visual word form area.     

Acute care functional assessment begins at the bedside

Patient functional ability is a determining factor in successful discharge and self-care. A model for improving the use of functional assessment in the acute care setting gives the bedside registered nurse a tool to manage care.     

Effects of word form on brain processing of written Chinese

Both logographic characters and alphabetic pinyins can be used to write words in Chinese. Here we use fMRI to address the question of whether the written form affects brain processing of a word. Fifteen healthy, right-handed, native Chinese-reading volunteers participated in our study and were asked to read silently either Chinese characters (8 subjects) or pinyins (7 subjects). The stimulus presentation rate was varied for both tasks to allow us to identify brain regions with word-load-dependent activation. Rate effects (fast minus slow presentations) for Chinese character reading were observed in striate and extrastriate visual cortex, superior parietal lobule, left posterior middle temporal gyrus, bilateral inferior temporal gyri, and bilateral superior frontal gyri. Rate effects for pinyin reading were observed in bilateral fusiform, lingual, and middle occipital gyri, bilateral superior parietal lobule/precuneus, left inferior parietal lobule, bilateral inferior temporal gyrus, left middle temporal gyrus, and left superior temporal gyrus. These results demonstrate that common regions of the brain are involved in reading both Chinese characters and pinyins, activated apparently independently of the surface form of the word. There also appear to be brain regions in which activation is dependent on word form. However, it is unlikely that these are entirely specific for a given word form; their activation more likely reflects relative functional specializations within broader networks for processing written language.     

The roles of the "visual word form area" in reading

Activation of the left midfusiform gyrus in response to reading words and pseudowords is such a reliable finding in functional imaging that this region has been called "the visual word form area" (VWFA). However, this label has recently been challenged, because activation in VWFA is also observed in other lexical tasks. We evaluated whether VWFA is necessary, sufficient, or specialized for reading by examining how frequently acute lesions in VWFA disrupt tasks that require access to written word forms versus other lexical tasks. We administered lexical tasks with spoken and written input and output, and identified damage or dysfunction of VWFA and other regions of interest (ROI) on diffusion- and perfusion-weighted imaging (DWI and PWI) in 80 patients within 24 h of onset of acute left ischemic stroke. Associations between abnormalities in each region of interest and impairment on lexical tasks were evaluated with chi-squared tests. Damage or dysfunction of VWFA was not significantly associated with impairment of written word comprehension or lexical decision, but was significantly associated with impairment on all tasks requiring lexical output: oral reading and oral naming (visual or tactile input), and written naming. We account for these results and results from functional imaging by proposing that the left midfusiform gyrus normally has two roles in reading: (1) computation of location- and modality-independent grapheme sequences from written word stimuli, and (2) a modality-independent stage of lexical processing that links modality-specific input and output representations. VWFA is not necessary for the former because the right homologue of VWFA can immediately assume this role.     

Brain activation and lexical learning: The impact of learning phase and word type

This study investigated the neural correlates of second-language lexical acquisition in terms of learning phase and word type. Ten French-speaking participants learned 80 Spanish words–40 cognates, 40 non-cognates–by means of a computer program. The learning process included the early learning phase, which comprised 5 days, and the consolidation phase, which lasted 2 weeks. After each phase, participants performed an overt naming task during an er-fMRI scan. Naming accuracy was better for cognates during the early learning phase only. However, cognates were named faster than non-cognates during both phases. The early learning phase was characterized by activations in the left iFG and Broca's area, which were associated with effortful lexical retrieval and phonological processing, respectively. Further, the activation in the left ACC and DLPFC suggested that monitoring may be involved during the early phases of lexical learning. During the consolidation phase, the activation in the left premotor cortex, the right supramarginal gyrus and the cerebellum indicated that articulatory planning may contribute to the consolidation of second-language phonetic representations. No dissociation between word type and learning phase could be supported. However, a Fisher r-to-z test showed that successful cognate retrieval was associated with activations in Broca's area, which could reflect the adaptation of known L1 phonological sequences. Moreover, successful retrieval of non-cognates was associated with activity in the anterior-medial left fusiform and right posterior cingulate cortices, suggesting that their successful retrieval may rely upon the access to semantic and lexical information, and even on the greater likelihood of errors.     

Learning word meanings during reading: Effects of phonological and semantic cues on children with language impairment

Abstract

Phonological and semantic deficits in spoken word learning have been documented in children with language impairment (LI), and cues that address these deficits have been shown to improve their word learning performance. However, the effects of such cues on word learning during reading remain largely unexplored. This study investigated whether (a) control, (b) phonological, (c) semantic, and (d) combined phonological-semantic conditions affected semantic word learning during reading in 9- to 11-year-old children with LI (n =?12) and with typical language (TL, n =?11) from low-income backgrounds. Children were exposed to 20 novel words across these four conditions prior to reading passages containing the novel words. After reading, a dynamic semantic assessment was given, which included oral definitions, contextual clues, and multiple choices. Results indicated that the LI group performed more poorly than the TL group in phonological and combined conditions, but not in the control or semantic conditions. Also, a similar trend for both groups was suggested, with improved performance in the semantic and combined conditions relative to the control and phonological conditions. Clinical implications include a continued need for explicit instruction in semantic properties of novel words to facilitate semantic word learning during reading in children with LI.     

Modulation of brain activity by multiple lexical and word form variables in visual word recognition: A parametric fMRI study

Psycholinguistic research has documented a range of variables that influence visual word recognition performance. Many of these variables are highly intercorrelated. Most previous studies have used factorial designs, which do not exploit the full range of values available for continuous variables, and are prone to skewed stimulus selection as well as to effects of the baseline (e.g. when contrasting words with pseudowords). In our study, we used a parametric approach to study the effects of several psycholinguistic variables on brain activation. We focussed on the variable word frequency, which has been used in numerous previous behavioural, electrophysiological and neuroimaging studies, in order to investigate the neuronal network underlying visual word processing. Furthermore, we investigated the variable orthographic typicality as well as a combined variable for word length and orthographic neighbourhood size (N), for which neuroimaging results are still either scarce or inconsistent. Data were analysed using multiple linear regression analysis of event-related fMRI data acquired from 21 subjects in a silent reading paradigm. The frequency variable correlated negatively with activation in left fusiform gyrus, bilateral inferior frontal gyri and bilateral insulae, indicating that word frequency can affect multiple aspects of word processing. N correlated positively with brain activity in left and right middle temporal gyri as well as right inferior frontal gyrus. Thus, our analysis revealed multiple distinct brain areas involved in visual word processing within one data set.     

功能性构音障碍临床表现及语言训练疗效分析

背景功能性构音障碍是在学龄前儿童和学龄期儿童中最常见的语言障碍,影响了患者日常的交流能力、心理发育、学习,成年患者甚至影响工作及社会交往.因此对功能性构音障碍患者进行语言评价及语言训练具有重大意义.目的探讨功能性构音障碍临床特点及康复治疗方法.设计病例分析.单位中山大学附属第三医院康复医学科.对象中山大学附属第三医院康复医学科收治的25例功能性构音障碍患者,其中15例为4～11岁学龄前期、学龄期儿童,10例为17～25岁成年人.方法对15例功能性构音障碍儿童及10例功能性构音障碍成人进行语言评价及语言训练.主要观察指标①功能性构音障碍临床特点.②儿童与成年患者语言治疗的治愈率.③观察语言训练的次数.结果构音检查方面,儿童与成人主要错误方式为歪曲、置换,主要错误音为舌尖前音、舌尖后音、舌根音、舌面音和舌尖音.平均错误音儿童与成人差别无显著性意义(P=O.910 0).训练时,引出每个目标音正确发音平均需时儿童较成人长(P=O.003),而每个目标音较熟练应用所需时间儿童较成人短(P=O.008).经训练15例儿童患者12例完全纠正,3例部分纠正;10例成人患者9例完全纠正,1例部分纠正后失访.结论功能性构音障碍临床特点儿童与成人差别不大,均以歪曲、置换的错误方式为主;语言训练效果好,但开始训练的时机应该适当,并非越早训练效果越好.     

Unconsciously deciphering handwriting: Subliminal invariance for handwritten words in the visual word form area

Expert readers exhibit a remarkable ability to recognize handwriting, in spite of enormous variability in character shape—a competence whose cerebral underpinnings are unknown. Subliminal priming, combined with neuroimaging, can reveal which brain areas automatically compute an invariant representation of visual stimuli. Here, we used behavioral and fMRI priming to study the areas involved in invariant handwritten word recognition. Compared to printed words, easily readable handwritten words caused additional activity in ventral occipitotemporal cortex, particularly in the right hemisphere, while difficult handwriting also mobilized an attentional parietofrontal network. Remarkably, however, subliminal repetition effects were observed across printed and handwritten styles, whether easy or difficult to read, both behaviorally and in the activation of the left visual word form area (VWFA). These results indicate that the left inferotemporal VWFA possesses an unsuspected degree of fast and automatic visual invariance for handwritten words, although surprisingly this invariance can be reflected both as repetition suppression and as repetition enhancement.     

Planning at the unit level

In recent years, management responsibilities at the unit level have expanded considerably. In this evolution of the nurse-manager role, the importance of the planning process in the overall productivity and success of the unit has gained widespread acceptance. To meet the challenges of today's health care climate, the nurse manager and the unit staff must have a clear understanding of what our business is, what it should be, and finally, depending on the plans developed, what it will be.     

Dynamic assessment of word learning skills of pre-school children with primary language impairment

Abstract

Dynamic assessment has been shown to have considerable theoretical and clinical significance in the assessment of socially disadvantaged and culturally and linguistically diverse children. In this study it is used to enhance assessment of pre-school children with primary language impairment. The purpose of the study was to determine whether a dynamic assessment (DA) has the potential to enhance the predictive capacity of a static measure of receptive vocabulary in pre-school children. Forty pre-school children were assessed using the static British Picture Vocabulary Scale (BPVS), a DA of word learning potential and an assessment of non-verbal cognitive ability. Thirty-seven children were followed up 6 months later and re-assessed using the BPVS. Although the predictive capacity of the static measure was found to be substantial, the DA increased this significantly especially for children with static scores below the 25th centile. The DA of children's word learning has the potential to add value to the static assessment of the child with low language skills, to predict subsequent receptive vocabulary skills and to increase the chance of correctly identifying children in need of ongoing support.     

功能性构音障碍语言评价及训练效果的分析

目的　探讨功能性构音障碍的临床特点及康复治疗。方法　对功能性构音障碍儿童 12例及功能性构音障碍成人 5例进行语言评价及语言训练 ,比较并分析儿童及成人功能性构音障碍患者的特点及疗效。结果　构音检查方面 ,儿童与成人的主要错误方式为歪曲、置换 ,主要的错误音为舌尖前音、舌尖后音、舌根音、舌面音和舌尖音。儿童与成人平均错误音差异无显著性 (P >0 .0 5 )。训练时 ,引出每个目标音正确发音平均需时儿童较成人长 (P <0 .0 0 1) ,而每个目标音较熟练应用所需时间儿童较成人短 (P <0 .0 0 1)。经训练后 ,12例儿童患者中有 10例完全纠正 ,2例部分纠正 ,治愈率为 83.33 % ,有效率为 10 0 .0 0 % ;5例成人患者全部纠正 ,治愈率为 10 0 .0 0 % ;总治愈率为 88.2 4% ,总有效率为 10 0 .0 0 %。结论　儿童与成人功能性构音障碍的临床特点差别不大 ,均以歪曲、置换的错误方式为主 ;语言训练效果好 ,但开始训练的时机应该适当 ,并非越早训练效果越好。