Word recognition in a phonemic dyslexic patient

Effectiveness of production and drawing as encoding techniques on recall using mixed- and pure-list designs

We compared the benefit of production and drawing on recall of concrete and abstract words, using mixed- and pure-list designs. We varied stimulus and list types to examine whether the memory benefit from these strategies was sustained across these manipulations. For all experiments, the memory retrieval task was free recall. In Experiment 1, participants studied concrete and abstract words sequentially, with prompts to either silently-read, read aloud, write, or draw each target (intermixed). Reading aloud, writing, and drawing improved recall compared to silent reading, with drawing leading to the largest boost. Performance, however, was at floor in all but the drawing condition. In Experiment 2, the number of targets was reduced, and each strategy (between-subjects) was compared to silent-reading. We eliminated floor effects and replicated results from Experiment 1. In Experiment 3, we manipulated strategy in a pure-list-design. The drawing benefit was maintained while that from production was eliminated. In all experiments, recall was higher for concrete than abstract words that were drawn; no such effect was found for words produced. Results suggest that drawing facilitates memory by enhancing semantic elaboration, whereas the production benefit is largely perceptually based. Importantly, the memory benefit conferred by drawing at encoding, unlike production, cannot be explained by a distinctiveness account as it was relatively unaffected by study design.

More than a scaffold: Language is a neuroenhancement

What role does language play in our thoughts? A longstanding proposal that has gained traction among supporters of embodied or grounded cognition suggests that it serves as a cognitive scaffold. This idea turns on the fact that language-with its ability to capture statistical regularities, leverage culturally acquired information, and engage grounded metaphors-is an effective and readily available support for our thinking. In this essay, I argue that language should be viewed as more than this; it should be viewed as a neuroenhancement. The neurologically realized language system is an important subcomponent of a flexible, multimodal, and multilevel conceptual system. It is not merely a source for information about the world but also a computational add-on that extends our conceptual reach. This approach provides a compelling explanation of the course of development, our facility with abstract concepts, and even the scope of language-specific influences on cognition.

Phonological Encoding in the Lexical Decision Task

In lexical decision experiments, subjects have difficulty in responding NO to non-words which are pronounced exactly like English words (e.g. BRANE). This does not necessarily imply that access to a lexical entry ever occurs via a phonological recoding of a visually-presented word. The phonological recoding procedure might be so slow that when the letter string presented is a word, access to its lexical entry via a visual representation is always achieved before phonological recoding is completed. If prelexical phonological recodings are produced by using grapheme-phoneme correspondence rules, such recodings can only occur for words which conform to these rules (regular words), since applications of the rules to words which do not conform to the rules (exception words) produce incorrect phonological representations. In two experiments, it was found that time to achieve lexical access (as measured by YES latency in a lexical decision task) was equivalent for regular words and exception words. It was concluded that access to lexical entries in lexical decision experiments of this sort does not proceed by sometimes or always phonologically recoding visually-presented words.

Reading for Meaning: The Effects of Concurrent Articulation

Six experiments are reported which examine the assertion that phonological recoding for the purpose of lexical access in visual word recognition is prevented or impaired by concurrent articulation (“articulatory suppression”). The first section of this paper selectively reviews the literature, and reports two experiments which fail to replicate previous work.

The third experiment contrasts performance with visually presented words and with non-words. Latency measures show an effect of suppression that is specific to words, whilst error rates show an effect common to both words and non-words. The fourth experiment shows that if the task is changed from a judgement of rhyme (BLAME-FLAME) to one of homophony (AIL-ALE), the suppression effect seen in the latency data is eliminated, whilst error effects remain. It is suggested that, in addition to producing error effects that are not easily interpretable, suppression prevents or impairs a phonological segmentation process operating subsequent to the retrieval of whole word phonology (a process that is needed for rhyme judgement but not for one of homophony).

Experiment V shows that while suppression has no effect on the time taken to decide if printed non-words sound like real words (e.g. PALLIS), error rates increase. Experiment VI shows that suppression has no effect on either RT or errors in the same task if subjects suppress at a slower rate than in Experiment V.

It is suggested that there are at least two different phonological codes. Buffer storage and/or maintenance of phonologically coded information derived from print is affected by suppression; phonological recoding from print for the purpose of lexical access can be carried out without any interference from suppression.

Semantic Errors or Statistical Flukes? a Note on Allport's “On Knowing the Meaning of Words We are Unable to Report”

Allport (1977) has claimed that normal subjects who view briefly a multi-word array, which is then pattern-masked, produce semantic errors analogous to those made by subjects with “deep dyslexia”. We claim that the rate at which normal subjects make such errors is consistent with their arising purely by chance.

Reading without Semantics

Analysis of the reading of a neurological patient (HTR) indicates that it is based on the operation of a relatively unimpaired phonological route. Quantitative investigations of type of error, reading speed and the effects of lexicality and spelling-to-sound regularity all support this conclusion. Spelling-to-sound regularity is shown to influence reading not only through regular words being better read than irregular, but also through mildly irregular words being better read than very irregular ones. A model is presented of the operation of the phonological route and of its progressive impairment in certain types of neurological disease.

Spelling Error Patterns of Normal, Learning-Disabled, and Underprepared College Writers

The spelling performance of normally achieving, learning-disabled, and underprepared college writers was examined across three measures to determine which, if any, measures were effective in differentiating among the three groups. The types of spelling errors made by each group also were examined. Results indicated that the Wide Range Achievement Test-Revised spelling subtest effectively distinguished among groups, while the other measures only distinguished between adequate (normal) and poor (learning-disabled and underprepared) writers. A modified version of Cromer's spelling error analysis was applied to a spontaneous writing sample and revealed no significant group differences with respect to type of spelling error between normal and underprepared writers. However, significant differences were found between the learning-disabled writers and both the normal and underprepared writers on all the spelling error types except spelling-rule errors.

The nature and treatment of phonological text agraphia

Phonological alexia and agraphia are written language disorders characterised by disproportionate difficulty reading and spelling nonwords in comparison to real words. In phonological alexia, it has been shown that, despite relatively accurate reading of words in isolation, text-level reading deficits are often marked and persistent. Specifically, some individuals demonstrate difficulty reading functors and affixes in sentences, a profile referred to as phonological text alexia. In this paper, we demonstrate an analogous manifestation of the phonological impairment on text-level writing and suggest the term "phonological text agraphia". We examined four individuals with phonological alexia/agraphia who also showed disproportionate difficulty writing well-formed sentences in comparison to their grammatical competence in spoken utterances. Implementation of a phonological treatment protocol resulted in significantly improved sublexical phonology skills as well as improvements in grammatical accuracy of written narratives. These findings support the notion of a common phonological impairment underlying nonword reading/spelling deficits and sentence-level difficulties.

Semantic Neighborhood Effects for Abstract versus Concrete Words

Studies show that semantic effects may be task-specific, and thus, that semantic representations are flexible and dynamic. Such findings are critical to the development of a comprehensive theory of semantic processing in visual word recognition, which should arguably account for how semantic effects may vary by task. It has been suggested that semantic effects are more directly examined using tasks that explicitly require meaning processing relative to those for which meaning processing is not necessary (e.g., lexical decision task). The purpose of the present study was to chart the processing of concrete versus abstract words in the context of a global co-occurrence variable, semantic neighborhood density (SND), by comparing word recognition response times (RTs) across four tasks varying in explicit semantic demands: standard lexical decision task (with non-pronounceable non-words), go/no-go lexical decision task (with pronounceable non-words), progressive demasking task, and sentence relatedness task. The same experimental stimulus set was used across experiments and consisted of 44 concrete and 44 abstract words, with half of these being low SND, and half being high SND. In this way, concreteness and SND were manipulated in a factorial design using a number of visual word recognition tasks. A consistent RT pattern emerged across tasks, in which SND effects were found for abstract (but not necessarily concrete) words. Ultimately, these findings highlight the importance of studying interactive effects in word recognition, and suggest that linguistic associative information is particularly important for abstract words.

Aphasia, Alexia, and Oral Reading

Alexia is an acquired disturbance in reading. Alexias that occur after left hemisphere damage typically result from linguistic deficits and may occur as isolated symptoms or as part of an aphasia syndrome. This article presents an overview of the classification of the alexias, including both the traditional neuroanatomical perspective and the more recent psycholinguistic approach. Then, assessment procedures are reviewed, followed by a summary of treatment approaches for alexia. Finally, two case studies illustrate how oral reading of connected language (sentences and paragraphs rather than single words) has been used as a technique for treating alexia in patients with aphasia.

Thinking in words: language as an embodied medium of thought

Recently, there has been a great deal of interest in the idea that natural language enhances and extends our cognitive capabilities. Supporters of embodied cognition have been particularly interested in the way in which language may provide a solution to the problem of abstract concepts. Toward this end, some have emphasized the way in which language may act as form of cognitive scaffolding and others have emphasized the potential importance of language-based distributional information. This essay defends a version of the cognitive enhancement thesis that integrates and builds on both of these proposals. I argue that the embodied representations associated with language processing serve as a supplementary medium for conceptual processing. The acquisition of a natural language provides a means of extending our cognitive reach by giving us access to an internalized combinatorial symbol system that augments and supports the context-sensitive embodied representational systems that exist independently of language.

Artificial language training reveals the neural substrates underlying addressed and assembled phonologies

Although behavioral and neuropsychological studies have suggested two distinct routes of phonological access, their neural substrates have not been clearly elucidated. Here, we designed an artificial language (based on Korean Hangul) that can be read either through addressed (i.e., whole word mapping) or assembled (i.e., grapheme-to-phoneme mapping) phonology. Two matched groups of native English-speaking participants were trained in one of the two conditions, one hour per day for eight days. Behavioral results showed that both groups correctly named more than 90% of the trained words after training. At the neural level, we found a clear dissociation of the neural pathways for addressed and assembled phonologies: There was greater involvement of the anterior cingulate cortex, posterior cingulate cortex, right orbital frontal cortex, angular gyrus and middle temporal gyrus for addressed phonology, but stronger activation in the left precentral gyrus/inferior frontal gyrus and supramarginal gyrus for assembled phonology. Furthermore, we found evidence supporting the strategy-shift hypothesis, which postulates that, with practice, reading strategy shifts from assembled to addressed phonology. Specifically, compared to untrained words, trained words in the assembled phonology group showed stronger activation in the addressed phonology network and less activation in the assembled phonology network. Our results provide clear brain-imaging evidence for the dual-route models of reading.

Is there a semantic system for abstract words?

Two views on the semantics of concrete words are that their core mental representations are feature-based or are reconstructions of sensory experience. We argue that neither of these approaches is capable of representing the semantics of abstract words, which involve the representation of possibly hypothetical physical and mental states, the binding of entities within a structure, and the possible use of embedding (or recursion) in such structures. Brain based evidence in the form of dissociations between deficits related to concrete and abstract semantics corroborates the hypothesis. Neuroimaging evidence suggests that left lateral inferior frontal cortex supports those processes responsible for the representation of abstract words.

Abstract and concrete phrases processing differentially modulates cortico-spinal excitability

An important challenge of embodied theories is to explain the comprehension of abstract sentences. The aim of the present study was to scrutinize the role of the motor cortex in this process. We developed a new paradigm to study the abstract-concrete dimension by combining concrete (i.e., action-related) and abstract (i.e., non-action-related) verbs with nouns of graspable and non-graspable objects. Using these verb-noun combinations we performed a Transcranial Magnetic Stimulation (TMS) on the left primary motor cortex while participants performed a sentence sensibility task. Single-TMS pulses were delivered 250ms after verb or noun presentation in each of four combinations of abstract and concrete verbs and nouns. To evaluate cortico-spinal excitability we registered the electromyographic activity of the right first dorsal interosseous muscle. As to verb-noun integration, analysis of motor evoked potentials (MEPs) after TMS pulse during noun presentation revealed greater peak-to-peak amplitude in phrases containing abstract rather than concrete verbs. Response times were also collected and showed that compatible (Concrete-Concrete and Abstract-Abstract) combinations were processed faster than mixed ones; moreover in combinations containing concrete verbs, participants were faster when the pulse was delivered on the first word (verb) than on the second one (noun). Results support previous findings showing early activation of hand-related areas after concrete verbs processing. The prolonged or delayed activation of the same areas by abstract verbs will be discussed in the framework of recent embodied theories based on multiple types of representation, particularly theories emphasizing the role of different acquisition mechanisms for concrete and abstract words (Borghi and Cimatti, 2009,2012).

Spelling and dysgraphia

Early cognitive models of spelling assumed that orthographic word representations are linear, ordered sequences of abstract letter identities (graphemes), activated only by word meaning information, and in some cases proposed that activating phonological information is a necessary stage of the spelling process. Over the past 20 years, studies on dysgraphia have shown that orthographic representations are autonomous from phonological representations and, just like the latter, are directly activated from semantics. The selection of an orthographic form for output relies on the convergence of activation from lexical-semantic information and from sublexical phoneme-grapheme conversion procedures. In addition, it is increasingly clear that orthographic representations are multidimensional objects that separately represent the graphosyllabic structure (or perhaps the nucleus/non-nucleus positions) of the target, and the identity, the CV status, and the quantity (doubling) of each grapheme. In spelling, the structure of orthographic knowledge and the mechanisms involved in processing serial order interact in complex ways and constrain performance accuracy. Further research is needed to clarify some critical issues: We need to specify in greater detail the mechanisms involved in the interaction between meaning and sublexical information; we must consider the possibility that orthographic representations have texture, in addition to structure; we must provide explicit hypotheses on the mechanisms that process orthographic knowledge; and we must gain a better understanding of the interaction between structure and serial order.

Précis of From neuropsychology to mental structure

Neuropsychological results are increasingly cited in cognitive theories although their methodology has been severely criticised. The book argues for an eclectic approach but particularly stresses the use of single-case studies. A range of potential artifacts exists when inferences are made from such studies to the organisation of normal function – for example, resource differences among tasks, premorbid individual differences, and reorganisation of function. The use of “strong” and “classical” dissociations minimises potential artifacts. The theoretical convergence between findings from fields where cognitive neuropsychology is well developed and those from the normal literature strongly suggests that the potential artifacts are not critical. The fields examined in detail in this respect are short-term memory, reading, writing, the organisation of input and output speech systems, and visual perception. Functional dissociation data suggest that not only are input systems organised modularly, but so are central systems. This conclusion is supported by findings on impairment of knowledge, visual attention, supervisory functions, memory, and consciousness.

Neural representation of abstract and concrete concepts: a meta-analysis of neuroimaging studies

A number of studies have investigated differences in neural correlates of abstract and concrete concepts with disagreement across results. A quantitative, coordinate-based meta-analysis combined data from 303 participants across 19 functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) studies to identify the differences in neural representation of abstract and concrete concepts. Studies that reported peak activations in standard space in contrast of abstract > concrete or concrete > abstract concepts at a whole brain level in healthy adults were included in this meta-analysis. Multilevel kernel density analysis (MKDA) was performed to identify the proportion of activated contrasts weighted by sample size and analysis type (fixed or random effects). Meta-analysis results indicated consistent and meaningful differences in neural representation for abstract and concrete concepts. Abstract concepts elicit greater activity in the inferior frontal gyrus and middle temporal gyrus compared to concrete concepts, while concrete concepts elicit greater activity in the posterior cingulate, precuneus, fusiform gyrus, and parahippocampal gyrus compared to abstract concepts. These results suggest greater engagement of the verbal system for processing of abstract concepts and greater engagement of the perceptual system for processing of concrete concepts, likely via mental imagery.

Semantic Typicality Effects in Acquired Dyslexia: Evidence for Semantic Impairment in Deep Dyslexia

BACKGROUND: Acquired deep dyslexia is characterized by impairment in grapheme-phoneme conversion and production of semantic errors in oral reading. Several theories have attempted to explain the production of semantic errors in deep dyslexia, some proposing that they arise from impairments in both grapheme-phoneme and lexical-semantic processing, and others proposing that such errors stem from a deficit in phonological production. Whereas both views have gained some acceptance, the limited evidence available does not clearly eliminate the possibility that semantic errors arise from a lexical-semantic input processing deficit. AIMS: To investigate semantic processing in deep dyslexia, this study examined the typicality effect in deep dyslexic individuals, phonological dyslexic individuals, and controls using an online category verification paradigm. This task requires explicit semantic access without speech production, focusing observation on semantic processing from written or spoken input. METHODS #ENTITYSTARTX00026; PROCEDURES: To examine the locus of semantic impairment, the task was administered in visual and auditory modalities with reaction time as the primary dependent measure. Nine controls, six phonological dyslexic participants, and five deep dyslexic participants completed the study. OUTCOMES #ENTITYSTARTX00026; RESULTS: Controls and phonological dyslexic participants demonstrated a typicality effect in both modalities, while deep dyslexic participants did not demonstrate a typicality effect in either modality. CONCLUSIONS: These findings suggest that deep dyslexia is associated with a semantic processing deficit. Although this does not rule out the possibility of concomitant deficits in other modules of lexical-semantic processing, this finding suggests a direction for treatment of deep dyslexia focused on semantic processing.

Are there independent lexical and nonlexical routes in word processing? An evaluation of the dual-route theory of reading

One of the most popular and influential theories of word processing, dual-route theory, proposes that there are two functionally independent means of processing words, one involving access to lexical knowledge and the other involving nonlexical grapheme-to-phoneme conversion. Three topics germane to this theory are the processing of nonwords, spelling regularity effects, and the manner in which reading may be impaired following selective damage to either route. This paper evaluates evidence on these topics, and in each case the claims of the theory for an independent nonlexical processing route are called into question. This conclusion is further supported by a discussion of the linguistic constraints that limit any nonlexical grapheme—phoneme conversion process. Some alternative approaches to visual word processing, which share the assumption that lexical knowledge can guide the assembly of phonological information, are discussed. It is argued that these approaches should direct future research.