Age of acquisition for naming and knowing: A new hypothesis

Understanding differing outcomes from semantic and phonological interventions with children with word-finding difficulties: A group and case series study

Developmental Language Disorder occurs in up to 10% of children and many of these children have difficulty retrieving words in their receptive vocabulary. Such word-finding difficulties (WFD) can impact social development and educational outcomes. This research aims to develop the evidence-base for supporting children with WFD and inform the design and analysis of intervention studies. We included 20 children (age 6 to 8) with WFD each of whom participated in two interventions one targeting semantic attributes and the other phonological attributes of target words. The interventions, employing word-webs, were carefully constructed to facilitate direct comparison of outcome which was analysed at both group and case-series level. The study used a robust crossover design with pre-intervention baseline, between-intervention wash-out and post-intervention follow-up testing. We incorporated: matching of item sets on individual performance at baseline, independent randomisation of order of intervention and items to condition, blinding of assessor, evaluation of fidelity and control items. The interventions were clinically feasible, with weekly sessions over six weeks. Intervention improved children's word-finding abilities with statistically significant change only during treatment phases of the study and not over baseline, wash-out or follow-up phases. For the group the semantic intervention resulted in a gain of almost twice as many items as the phonological intervention, a significant difference. However, children differed in their response to intervention. Importantly, case-series analysis revealed outcomes predictable on the basis of children's theoretically driven language profiles. Taking account of individual profiles in determining choice of intervention would enable more children to benefit. The study provides new evidence to inform and refine clinical practice with this population. Future studies should be designed such that results can be analysed at both group and case series levels to extend theoretical understanding and optimise use of appropriate interventions.

What a pooled data study tells us about the relationships between gender and knowledge of semantic categories

Introduction: Both the neuropsychological study of patients with category-specific semantic disorders (CSSD) and the experimental research on categorical processing in healthy subjects (HSs) have shown that men are mainly impaired with fruits and vegetables and women with animals and artifacts. Since this difference is more striking in patients with CSSD than in HSs, we hypothesized that the lack of power of some investigations conducted with HSs and the different methods used in studies conducted with HSs and patients with CSSD could explain some of these inconsistencies and that a study conducted with a very large number of HSs using visual naming tasks should strongly confirm the role of gender in categorical tasks. Methods: Picture naming data gathered during the last ten years with our category-specificity paradigm from a large number (702) of HSs were reanalyzed. Results: As predicted, men named significantly more animals and artifacts, while women named more plant life items. Discussion: These data confirm that, if different domains of knowledge are studied in a very large sample of HSs using a picture naming task equivalent to the naming tasks used in most anatomo-clinical studies on CSSD, then the gender effects are highly significant.

Intervention for children with word-finding difficulties: a parallel group randomised control trial

PURPOSE

The study investigated the outcome of a word-web intervention for children diagnosed with word-finding difficulties (WFDs).

METHOD

Twenty children age 6-8 years with WFDs confirmed by a discrepancy between comprehension and production on the Test of Word Finding-2, were randomly assigned to intervention (n = 11) and waiting control (n = 9) groups. The intervention group had six sessions of intervention which used word-webs and targeted children's meta-cognitive awareness and word-retrieval.

RESULT

On the treated experimental set (n = 25 items) the intervention group gained on average four times as many items as the waiting control group (d = 2.30). There were also gains on personally chosen items for the intervention group. There was little change on untreated items for either group.

CONCLUSION

The study is the first randomised control trial to demonstrate an effect of word-finding therapy with children with language difficulties in mainstream school. The improvement in word-finding for treated items was obtained following a clinically realistic intervention in terms of approach, intensity and duration.

Right-hemisphere reading in a case of developmental deep dyslexia

The right-hemisphere hypothesis of deep dyslexia has received support from functional imaging studies of acquired deep dyslexia following damage to the left cerebral hemisphere, but no imaging studies of cases of developmental deep dyslexia, in which brain damage is not suspected, have been reported. In this paper, we report the first evidence of right hyperactivation in an adult case of developmental deep dyslexia. Hyperactivation was observed in the right inferior frontal cortex during functional magnetic resonance imaging (fMRI) of the oral reading of imageable content words and nonwords to which imageable lexical responses were frequently made. No evidence of right hyperactivation was observed in the oral reading of function words, nor during the naming of imageable words in response to pictured objects. The results reveal strategic and selective use of right-hemisphere functions for particular types of written stimuli. We propose that children with developmental deep dyslexia compensate for their lack of phonological skills by accessing right-hemisphere imageable associations that provide a mnemonic for linking written forms to spoken names.

Are Sex-Related Category-Specific Differences in Semantic Tasks Innate or Influenced by Social Roles? A Viewpoint

In semantic tasks, sex-related categorical differences, in the form of better processing of fruits and vegetables by women and of artifacts (human-made objects) and animals by men, have been reported both in healthy participants and in brain-damaged patients. Researchers' interpretation of these sex-related categorical asymmetries has, however, been controversial, being connected with the more general (innatist versus experience-dependent) interpretations that had been given of the mechanisms subsuming the categorical organization of the brain. I begin this review with a brief reminder of the debate between supporters of the innatist and the experience-related accounts of categorical brain organization. Then I summarize results that have documented a preference by women for fruits and vegetables and a preference by men for artifacts and animals, and I discuss the innatist and social role-related interpretations that have been given of these results. I conclude that sex-related categorical effects disappear in generations in which the traditional social roles have almost completely disappeared, and these differences are not seen in young individuals raised in societies that emphasize sex equality.

Reading comprehension in children with Down syndrome

Two studies aimed to investigate the reading comprehension abilities of 14 readers with Down syndrome aged 6 years 8 months to 13 years relative to those of typically developing children matched on word reading ability, and to investigate how these abilities were associated with reading accuracy, listening comprehension, phonological awareness and vocabulary knowledge. Study 1 confirmed significantly poorer passage-reading comprehension than the typically developing group. In an experimental task, readers with Down syndrome understood fewer written sentences than the typical group and, contrary to prediction, received no advantage from printed sentences compared to spoken sentences, despite the lower memory load. Reading comprehension was associated with listening comprehension, word reading and phonological awareness in DS. Vocabulary knowledge was also associated with reading comprehension, mediated by word reading and nonverbal cognitive abilities. Study 2 investigated the longitudinal relationships between reading and language measures in the readers with DS over around 22 months. Time 1 listening comprehension and phonological awareness predicted Time 2 reading comprehension but there was no evidence that reading or reading comprehension predicted Time 2 language scores or phonological awareness, and no evidence that readers had acquired greater depth of vocabulary.

Cognitive processing of currency: Euros and Dollars

In the current study, we evaluated whether the processing of currency was determined by familiarity of people with banknotes. In Experiment 1, participants who used the Euro currency named sequences of Euro banknotes and Dollar banknotes blocked by category or mixed with exemplars of other categories. The participants showed an interference effect in the blocked context with Dollar banknotes but not with Euro banknotes. In Experiment 2, the interference effect was observed with Euro banknotes when participants were not familiar with the Euro currency. These results suggest that the semantic processing of banknotes depends on the participants' familiarity with currency.

Inborn and experience-dependent models of categorical brain organization. A position paper

The present review aims to summarize the debate in contemporary neuroscience between inborn and experience-dependent models of conceptual representations that goes back to the description of category-specific semantic disorders for biological and artifact categories. Experience-dependent models suggest that categorical disorders are the by-product of the differential weighting of different sources of knowledge in the representation of biological and artifact categories. These models maintain that semantic disorders are not really category-specific, because they do not respect the boundaries between different categories. They also argue that the brain structures which are disrupted in a given type of category-specific semantic disorder should correspond to the areas of convergence of the sensory-motor information which play a major role in the construction of that category. Furthermore, they provide a simple interpretation of gender-related categorical effects and are supported by studies assessing the importance of prior experience in the cortical representation of objects On the other hand, inborn models maintain that category-specific semantic disorders reflect the disruption of innate brain networks, which are shaped by natural selection to allow rapid identification of objects that are very relevant for survival. From the empirical point of view, these models are mainly supported by observations of blind subjects, which suggest that visual experience is not necessary for the emergence of category-specificity in the ventral stream of visual processing. The weight of the data supporting experience-dependent and inborn models is thoroughly discussed, stressing the fact observations made in blind subjects are still the subject of intense debate. It is concluded that at the present state of knowledge it is not possible to choose between experience-dependent and inborn models of conceptual representations.

Receptive vocabulary and semantic knowledge in children with SLI and children with Down syndrome

Receptive vocabulary and associated semantic knowledge were compared within and between groups of children with specific language impairment (SLI), children with Down syndrome (DS), and typically developing children. To overcome the potential confounding effects of speech or language difficulties on verbal tests of semantic knowledge, a novel task was devised based on picture-based semantic association tests used to assess adult patients with semantic dementia. Receptive vocabulary, measured by word-picture matching, of children with SLI was weak relative to chronological age and to nonverbal mental age but their semantic knowledge, probed across the same lexical items, did not differ significantly from that of vocabulary-matched typically developing children. By contrast, although receptive vocabulary of children with DS was a relative strength compared to nonverbal cognitive abilities (p < .0001), DS was associated with a significant deficit in semantic knowledge (p < .0001) indicative of dissociation between word-picture matching vocabulary and depth of semantic knowledge. Overall, these data challenge the integrity of semantic-conceptual development in DS and imply that contemporary theories of semantic cognition should also seek to incorporate evidence from atypical conceptual development.

Separating lexical-semantic access from other mnemonic processes in picture-name verification

We present a novel paradigm to identify shared and unique brain regions underlying non-semantic, non-phonological, abstract, audio-visual (AV) memory vs. naming using a longitudinal functional magnetic resonance imaging experiment. Participants were trained to associate novel AV stimulus pairs containing hidden linguistic content. Half of the stimulus pairs were distorted images of animals and sine-wave speech versions of the animal's name. Images and sounds were distorted in such a way as to make their linguistic content easily recognizable only after being made aware of its existence. Memory for the pairings was tested by presenting an AV pair and asking participants to verify if the two stimuli formed a learned pairing. After memory testing, the hidden linguistic content was revealed and participants were tested again on their recollection of the pairings in this linguistically informed state. Once informed, the AV verification task could be performed by naming the picture. There was substantial overlap between the regions involved in recognition of non-linguistic sensory memory and naming, suggesting a strong relation between them. Contrasts between sessions identified left angular gyrus and middle temporal gyrus as key additional players in the naming network. Left inferior frontal regions participated in both naming and non-linguistic AV memory suggesting the region is responsible for AV memory independent of phonological content contrary to previous proposals. Functional connectivity between angular gyrus and left inferior frontal gyrus and left middle temporal gyrus increased when performing the AV task as naming. The results are consistent with the hypothesis that, at the spatial resolution of fMRI, the regions that facilitate non-linguistic AV associations are a subset of those that facilitate naming though reorganized into distinct networks.

Using ratings to gain insight into conceptual development

PURPOSE

The authors explored a novel technique with potential for assessing conceptual development. Participants rated how "normal" to "really weird" an image was in order to determine whether (a) participants would rate images by amount of variation (slight/significant) from the standard image, (b) participants would treat variation related to different concepts equally, or (c) there would be developmental differences in these ratings. Then, authors asked whether children with specific language impairment (SLI) would demonstrate weaker conceptual skills based on their ratings.

METHOD

Adults and school-age children (with and without SLI) used a 9-point equal-appearing interval scale to rate photographic images of animals. These included standard images and images that altered the animals' shape, pattern, color, and facial morphometry.

RESULTS

Significant differences in ratings were obtained for adults compared with typically developing children and children with SLI compared with their age-matched peers. This is in line with the expectation that adults have stronger representations than children, as do typical children compared with those with SLI. Participants differentially rated images that varied from the standard image (slight/significant) for all parameters except shape.

CONCLUSION

Probing conceptual representations without the need for verbal response has the potential for exploring conceptual deficits in SLI.

Sex Differences in Visual Realism in Drawings of Animate and Inanimate Objects

Sex differences in a visually realistic drawing style were examined using the model of a curvy cup as an inanimate object, and the Draw-A-Person test (DAP) as a task involving animate objects, with 7- to 12-year-old children ( N = 60; 30 boys). Accurately drawing the internal detail of the cup—indicating interest in a depth feature—was not dependent on age in boys, but only in girls, as 7-year-old boys were already engaging with this cup feature. However, the age effect of the correct omission of an occluded handle—indicating a transition from realism in terms of function (intellectual realism) to one of appearance (visual realism)—was the same for both sexes. The correct omission of the occluded handle was correlated with bilingualism and drawing the internal cup detail in girls, but with drawing the silhouette contour of the cup in boys. Because a figure's silhouette enables object identification from a distance, while perception of detail and language occurs in nearer space, it was concluded that boys and girls may differ in the way they conceptualize depth in pictorial space, rather than in visual realism as such.

Development of a vocabulary of object shapes in a child with a very-early-acquired visual agnosia: A unique case

We report a longitudinal study of an exceptional child (S.R.) whose early-acquired visual agnosia, following encephalitis at 8 weeks of age, did not prevent her from learning to construct an increasing vocabulary of visual object forms (drawn from different categories), albeit slowly. S.R. had problems perceiving subtle differences in shape; she was unable to segment local letters within global displays; and she would bring complex scenes close to her eyes: a symptom suggestive of an attempt to reduce visual crowding. Investigations revealed a robust ability to use the gestalt grouping factors of proximity and collinearity to detect fragmented forms in noisy backgrounds, compared with a very weak ability to segment fragmented forms on the basis of contrasts of shape. When contrasts in spatial grouping and shape were pitted against each other, shape made little contribution, consistent with problems in perceiving complex scenes, but when shape contrast was varied, and spatial grouping was held constant, S.R. showed the same hierarchy of difficulty as the controls, although her responses were slowed. This is the first report of a child's visual–perceptual development following very early neurological impairments to the visual cortex. Her ability to learn to perceive visual shape following damage at a rudimentary stage of perceptual development contrasts starkly with the loss of such ability in childhood cases of acquired visual agnosia that follow damage to the established perceptual system. Clearly, there is a critical period during which neurological damage to the highly active, early developing visual–perceptual system does not prevent but only impairs further learning.

Object and action naming in children with specific language impairment

PURPOSE

In this study, the authors aimed to examine the accuracy, latency, and errors of noun (object) and verb (action) naming in children with and without specific language impairment (SLI) and to determine whether children with SLI have a particularly large noun-verb performance gap.

METHOD

Children with SLI, age-matched peers (AM), and expressive vocabulary-matched peers (VM) named 120 matched object and action pictures in a computerized confrontation naming task.

RESULTS

The SLI and VM groups demonstrated comparable naming latency and accuracy; both were slower and less accurate than the AM group. Object naming was more accurate than action naming in the SLI and VM groups; their noun-verb performance gaps were comparable. Object naming was faster than action naming in all children. In comparison with the AM group, the SLI group made proportionally fewer taxonomic errors and more omission errors when naming objects, and fewer misperception errors when naming actions.

CONCLUSIONS

The naming abilities of children with SLI, although deficient given their chronological age, are commensurate with their vocabulary level. Their naming errors suggest immaturities in semantic representation. Action naming is significantly more difficult than object naming, but the noun-verb gap that characterizes the performance of children with SLI is appropriate for their vocabulary level.

Age of acquisition effects in vocabulary learning

Two experiments examined whether the age of acquisition (AoA) of a concept influences the speed at which native English speakers are able to name pictures using a newly acquired second language (L2) vocabulary. In Experiment 1, participants were taught L2 words associated with pictures. In Experiment 2 a second group of participants were taught the same words associated with L1 translations. Following training both groups performed a picture naming task in which they were asked to name pictures using the newly acquired words. Significant AoA effects were observed only in Experiment 1, in that participants were faster at naming pictures representing early acquired relative to late acquired concepts. The results suggest that the AoA of a concept can exert influence over processing which is independent of the AoA of the word form. The results also indicate that different training methods may lead to qualitative differences in the nature of the links formed between words and concepts during the earliest stages of second language learning.

Age of Acquisition, Word Frequency, and Picture–Word Interference

In two experiments participants named pictures superimposed with unrelated words. The age of acquisition (AoA) of the picture names was manipulated. Additionally, the word frequency (WF, Experiment 1) or AoA (Experiment 2) of the interfering distractor words was manipulated. Early-acquired pictures were named faster than their late-acquired counterparts. Both WF and AoA modulated the degree of interference from the irrelevant word; low-frequency and late-acquired words produced most interference. In neither case did the WF or AoA of the distractor word interact with the AoA of the picture. The results show that in the context of word processing both WF and AoA have similar effects.

Name-picture verification as a control measure for object naming: a task analysis and norms for a large set of pictures

The name-picture verification task is widely used in spoken production studies to control for nonlexical differences between picture sets. In this task a word is presented first and followed, after a pause, by a picture. Participants must then make a speeded decision on whether both word and picture refer to the same object. Using regression analyses, we systematically explored the characteristics of this task by assessing the independent contribution of a series of factors that have been found relevant for picture naming in previous studies. We found that, for "match" responses, both visual and conceptual factors played a role, but lexical variables were not significant contributors. No clear pattern emerged from the analysis of "no-match" responses. We interpret these results as validating the use of "match" latencies as control variables in studies or spoken production using picture naming. Norms for match and no-match responses for 396 line drawings taken from Cycowicz, Friedman, Rothstein, and Snodgrass (1997) can be downloaded at: http://language.psy.bris.ac.uk/name-picture_verification.html.

Coding of visual object features and feature conjunctions in the human brain

Object recognition is achieved through neural mechanisms reliant on the activity of distributed coordinated neural assemblies. In the initial steps of this process, an object's features are thought to be coded very rapidly in distinct neural assemblies. These features play different functional roles in the recognition process--while colour facilitates recognition, additional contours and edges delay it. Here, we selectively varied the amount and role of object features in an entry-level categorization paradigm and related them to the electrical activity of the human brain. We found that early synchronizations (approx. 100 ms) increased quantitatively when more image features had to be coded, without reflecting their qualitative contribution to the recognition process. Later activity (approx. 200-400 ms) was modulated by the representational role of object features. These findings demonstrate that although early synchronizations may be sufficient for relatively crude discrimination of objects in visual scenes, they cannot support entry-level categorization. This was subserved by later processes of object model selection, which utilized the representational value of object features such as colour or edges to select the appropriate model and achieve identification.

How young children judge whether a word is one they know: a dual criterion account

Word familiarity judgment may be important for word learning, yet little is known about how children make this judgment. We hypothesized that preschool-age children differ in the judgment criteria that they use and that this difference derives from individual differences in basic memory processes. Those who have superior phonological working memory, but who retrieve less semantic information than their peers, base the judgment on whether they recognize a word's sound form. Those who show the opposite memory profile base the judgment on whether they retrieve a word's meaning. The results of two studies of 3- and 4-year-olds were consistent with these claims. Among those performing poorly on one memory measure, judgment accuracy was directly related to performance on the other memory measure. These memory-judgment relations were also found to be highly specific. This is the first investigation to demonstrate the usefulness of an individual differences approach for identifying relations between linguistic judgment processes and basic memory processes during early childhood.

Object and action picture naming in three- and five-year-old children

The objectives were to explore the often reported noun advantage in children's language acquisition using a picture naming paradigm and to explore the variables that affect picture naming performance. Participants in Experiment 1 were aged three and five years, and in Experiment 2, five years. The stimuli were action and object pictures. In Experiment 1, action pictures produced more errors than object pictures for the three-year-olds, but not the five-year-olds. A qualitative analysis of the errors revealed a somewhat different pattern of errors across age groups. In Experiment 2 there was no robust difference in accuracy for the actions and objects but naming times were longer for actions. Across both experiments, imageability was a robust predictor of object naming performance, while spoken frequency was the most important predictor of action naming. The results are discussed in terms of possible differences in the manner in which nouns and verbs are acquired.

Support for hybrid models of the age of acquisition of English nouns

Age of acquisition (AoA) is a psycholinguistic construct that refers to the chronological age at which a given word is acquired. Contemporary theories of AoA have focused on lexical acquisition with respect to either the developing phonological or semantic systems. One way of testing the relative dominance of phonological or semantic contributions is through open-source psycholinguistic databases, whereby AoA may be correlated with other variables (e.g., morphology, semantics, phonology). We report two multiple regression analyses conducted on a corpus of English nouns with, respectively, subjective and objective AoA measures as the dependent variables and a combination of 10 predictors, including 2 semantic, 4 phonological, 2 morphological, and 2 lexical. This multivariate combination of predictors accounted for significant proportions of the variance ofAoA in both analyses. We argue that this evidence supports hybrid models of language development that integrate multiple levels of processing-from sound to meaning.

Complexities of expressive word learning over time

PURPOSE

The purpose of this study was to examine semantic and lexical aspects of word learning over time.

METHOD

Thirty-four 8-year-olds participated in vocabulary lessons for 2 weeks. Frequency of exposure and informativeness of semantic context were manipulated. A definition task assessed semantic learning and a naming task assessed lexical learning.

RESULTS

Semantic and lexical knowledge accrued over time and were maintained after a 1-month interval. Higher frequency of exposure had an immediate effect on semantic learning and a more gradual effect on lexical learning. Frequency of exposure coupled with informative context promoted semantic learning.

CLINICAL IMPLICATIONS

Speech-language pathologists should be mindful of the richness of the learning context and the redundancy of massed and distributed exposures. Learning at the semantic and lexical levels can dissociate so both should be addressed.

Objective age of acquisition norms for a set of 328 words in Spanish

Age of acquisition is one of the most important variables in picture naming. For this reason, a large number of findings concerning age-of-acquisition data have been published in recent years in a number of different languages. In this article, objective age-of-acquisition data in Spanish for 328 pictures were collected from a pool of 760 children, half of whom were boys and the other half girls. A total of 246 pictures were selected from the Snodgrass and Vanderwart (1980) set, and 82 were new pictures. Like the results of other studies, we found that objective age of acquisition correlates less than rated age of acquisition with familiarity and frequency, which indicates that the objective measure is less contaminated by other variables than are rated estimates. A very high correlation was obtained between the norms from this study and those published in English, French, Icelandic, and Italian. These norms will be very useful to Spanish psycholinguists and clinicians. Related materials may be downloaded from the Psychonomic Society Web archive at www.psychonomic.org/archive/.

Different variables predict anomia in different subjects: a longitudinal study of two Alzheimer's patients

Two Alzheimer's patients participated in a longitudinal study of picture naming aimed at analysing the effect of lexical frequency, age of acquisition, stimulus familiarity, word length, name imageability, visual complexity and semantic category membership on naming success. The results were analysed with a new method [Capitani, E., & Laiacona, M. (2004). A method for studying the evolution of naming error types in the recovery of acute aphasia: A single-patient and single-stimulus approach. Neuropsychologia, 42, 613-623] that allows us to consider the consistency of responses to stimuli over repeated testing within clinical stages. The experiment was carried out as a longitudinal study of single cases, and the effect of each variable was estimated after removing the overlap with the other predictors. The semantic category of stimuli was not an influential factor for either patient. Other findings sharply distinguished between the two patients. In one case, disease-related decline consistently affected mainly late acquired names, whereas in the other case the decline affected names corresponding to low-familiarity items. To interpret this contrast, we further analysed the quality of the errors produced by each patient. This study shows that the psycholinguistic characteristics of a stimulus may exert varying influence in different patients, warranting further development of this line of inquiry.

Reflections on how color term acquisition is constrained

Compared with object word learning, young children typically find learning color terms to be a difficult linguistic task. In this reflections article, I consider two questions that are fundamental to investigations into the developmental acquisition of color terms. First, I consider what constrains color term acquisition and how stable these constraints are over culture and age. I review recent studies that have identified conceptual, attentional, and linguistic constraints that seemingly operate on the acquisition of color terms compared with object words and the differential acquisition of color terms within a given language. Second, I consider whether these constraints are specific to the acquisition of color terms or whether they reflect more general constraints that operate on other classes of lexical terms such as different abstract property terms.