首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The aim of this study was to explore the differences in procedural learning abilities between children with DCD and typically developing children by investigating the steps that lead to skill automatization (i.e., the stages of fast learning, consolidation, and slow learning). Transfer of the skill to a new situation was also assessed. We tested 34 children aged 6–12 years with and without DCD on a perceptuomotor adaptation task, a form of procedural learning that is thought to involve the cerebellum and the basal ganglia (regions whose impairment has been associated with DCD) but also other brain areas including frontal regions. The results showed similar rates of learning, consolidation, and transfer in DCD and control children. However, the DCD children's performance remained slower than that of controls throughout the procedural task and they reached a lower asymptotic performance level; the difficulties observed at the outset did not diminish with practice.  相似文献   

2.
    
Children with developmental language disorder (DLD) have significant deficits in language ability that cannot be attributed to neurological damage, hearing impairment, or intellectual disability. The symptoms displayed by children with DLD differ across languages. In English, DLD is often marked by severe difficulties acquiring verb inflection. Such difficulties are less apparent in languages with rich verb morphology like Spanish and Italian. Here we show how these differential profiles can be understood in terms of an interaction between properties of the input language, and the child's ability to learn predictive relations between linguistic elements that are separated within a sentence. We apply a simple associative learning model to sequential English and Spanish stimuli and show how the model's ability to associate cues occurring earlier in time with later outcomes affects the acquisition of verb inflection in English more than in Spanish. We relate this to the high frequency of the English bare form (which acts as a default) and the English process of question formation, which means that (unlike in Spanish) bare forms frequently occur in third-person singular contexts. Finally, we hypothesize that the pro-drop nature of Spanish makes it easier to associate person and number cues with the verb inflection than in English. Since the factors that conspire to make English verb inflection particularly challenging for learners with weak sequential learning abilities are much reduced or absent in Spanish, this provides an explanation for why learning Spanish verb inflection is relatively unaffected in children with DLD.  相似文献   

3.
IntroductionThe overall goal of the study was to draw, in French language, a complete picture of spelling abilities in young students with SLI, enrolling in ordinary classes.ObjectiveThe main aim was to show how the developmental trajectories of lexical spelling and the morphological spelling are different when a large age span is observed (7 to 18 years old).MethodsThe spelling abilities were evaluated through a narrative communicative. Two groups of students with SLI (7–11 years and 12–18 years) were compared with two groups of typical students matched on chronological age.ResultsThe lexical spelling was acquired before the morphological spelling for SLI and typical participants. At 12–18 of age, the SLI participants did not produce more lexical errors than the typical group. For the lexical spelling, at 7–11 years, the SLI participants had a specific difficulty with the segmentation of the words: they produced words that do not exist in the language and which by definition have no morphological markers.ConclusionThe SLI participants need more time to learn than the typical participants. At 7–11 years, before learning of morphology, they must be able to control segmentation the segmentation of words. The low number of morphological errors in the school SLI group of 7–11 years is not necessarily a sign of difficulty. The increase in the number of errors at 12–18 years is the sign that this problem has been exceeded and that the learning of the written morphological markers can really begin.  相似文献   

4.
    
Different processes are involved during visuomotor learning, including an error-based procedural and a strategy based cognitive mechanism. Our objective was to analyze if the changes in the adaptation or the aftereffect components of visuomotor learning measured across development, reflected different maturation rates of the aforementioned mechanisms. Ninety-five healthy children aged 4–12 years and a group of young adults participated in a wedge prism and a dove prism throwing task, which laterally displace or horizontally reverse the visual field respectively. The results show that despite the age-related differences in motor control, all children groups adapted in the error-based wedge prisms condition. However, when removing the prism, small children showed a slower aftereffects extinction rate. On the strategy-based visual reversing task only the older children group reached adult-like levels. These results are consistent with the idea of different mechanisms with asynchronous maturation rates participating during visuomotor learning.  相似文献   

5.
This study examines performance at a syllogistic reasoning task for a group of children (age 10 years) with specific language impairment (SLI) along with age- and language-matched controls. The syllogisms were presented either verbally or verbally/pictorially, and contained two types of item: imaginary versus real, both intended not to evoke strong beliefs. Children with SLI performed worse than age-matched controls, and equivalently to language-matched controls. Patterns of performance indicate this may be due to cognitive ability deficits rather than specific language deficits. For all groups, pictorial presentation interfered with reasoning processes. It is suggested that, for syllogisms, this pictorial information contextualises the interpretation of the task, and that in turn either raises working memory load or evokes belief bias. Additionally, these results suggest that caution should be exhibited before using visual aids to help children with SLI in the classroom.  相似文献   

6.
Sixty-five children with specific reading disability (SRD), 25 children with specific language impairment (SLI), and 37 age-matched controls were tested for their frequency discrimination, rapid auditory processing, vowel discrimination, and consonant–vowel discrimination. Subgroups of children with SRD or SLI produced abnormal frequency discrimination (42%), rapid auditory processing (12%), vowel discrimination (23%), or consonant–vowel discrimination (18%) thresholds for their age. Twenty-eight of these children trained on a programme that targeted their specific auditory processing deficit for 6 weeks. Twenty-five of these 28 trainees produced normal thresholds for their targeted processing skill after training. These gains were not explained by gains in auditory attention, in the ability to do psychophysical tasks in general, or by test–retest effects. The 25 successful trainees also produced significantly higher scores on spoken language and spelling tests after training. However, an untrained control group showed test–retest effects on the same tests. These results suggest that auditory processing deficits can be treated successfully in children with SRD and SLI but that this does not help them acquire new reading, spelling, or spoken language skills.  相似文献   

7.
8.
Rapid processing deficits have been the subject of much debate in the literature on specific language impairment (SLI). Hari and Renvall (2001) [Hari, R. & Renvall, H. (2001). Impaired processing of rapid stimulus sequences in dyslexia. Trends in cognitive sciences, 5, 525-532.] proposed that the source of this deficit can be attributed to sluggish attentional shifting abilities. That is, more time is required to shift attention between stimuli. To test this claim, 26 adolescents with SLI (divided into two subgroups to control for differences in non-verbal intelligence) and 14 controls were presented with a rapid serial visual presentation task. In this task participants were asked to detect two visual targets presented serially with distracter items with varying inter-target intervals (i.e., time difference between targets). This task was designed to elicit an attentional blink (AB). The AB describes the phenomenon whereby non-impaired individuals are less likely to report the second of two targets presented within 200-500ms of each other. After controlling for group differences in non-verbal intelligence, the SLI group was found to be significantly less accurate than the control group at successfully reporting the second target at inter-target intervals of 100, 200, 300, 400 and 800ms. The results were interpreted to suggest that adolescents with language impairments have an AB which differs from non-impaired individuals in both magnitude and duration.  相似文献   

9.
McArthur and Bishop (2004) found that people with specific language impairment (SLI) up to 14 years of age have poor behavioural frequency discrimination (FD) thresholds for 25-ms pure tones, while people with SLI upto 20 years of age have abnormal auditory N1--P2--N2 event-related potential (ERP) responses to the same tones. In the present study, we extended these findings to more complex non-speech and speech sounds by comparing younger (around 13 years) and older (around 17 years) teenagers with SLI and controls for their behavioural FD thresholds and N1-P2 ERPs to 25 and 250-ms pure tones, vowels, and non-harmonic complex tones. We found that a subgroup of people with SLI had abnormal responses to tones and vowels at the level of behaviour and the brain, and that poor processing was associated with the spectral complexity of auditory stimuli rather than their phonetic significance. We suggest that both the age of listeners and the sensitivity of psychoacoustic tasks to age-related changes in auditory skills may be crucial factors in studies of sound processing in SLI.  相似文献   

10.
The prism adaptation test examines procedural learning (PL) in which performance facilitation occurs with practice on tasks without the need for conscious awareness. Dynamic interactions between frontostriatal cortices, basal ganglia, and the cerebellum have been shown to play key roles in PL. Disruptions within these neural networks have also been implicated in schizophrenia, and such disruptions may manifest as impairment in prism adaptation test performance in schizophrenia patients. This study examined prism adaptation in a sample of patients diagnosed with schizophrenia (N=91) and healthy normal controls (N=58). Quantitative indices of performance during prism adaptation conditions with and without visual feedback were studied. Schizophrenia patients were significantly more impaired in adapting to prism distortion and demonstrated poorer quality of PL. Patients did not differ from healthy controls on aftereffects when the prisms were removed, but they had significantly greater difficulties in reorientation. Deficits in prism adaptation among schizophrenia patients may be due to abnormalities in motor programming arising from the disruptions within the neural networks that subserve PL.  相似文献   

11.
    
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.  相似文献   

12.
13.
This study focuses on the comorbidity between attention-deficit/hyperactivity disorder (ADHD) symptoms and speech sound disorder (SSD). SSD is a developmental disorder characterized by speech production errors that impact intelligibility. Previous research addressing this comorbidity has typically used heterogeneous groups of speech-language disordered children. This study employed more precise speech-language diagnostic criteria and examined ADHD symptomatology in 108 SSD children between the ages of 4 and 7 years old with specific language impairment (SLI) (n = 23, 14 males, 9 females) and without SLI (n = 85, 49 males, 36 females). We also examined whether a subcategory of SSD, persistent (n = 39, 25 males, 14 females) versus normalized SSD (n = 67, 38 males, 29 females), was associated with ADHD and/or interacted with SLI to predict ADHD symptomatology. Results indicated that participants in the SSD + SLI group had higher rates of inattentive ADHD symptoms than those in the SSD-only and control groups. In addition, an unexpected interaction emerged such that children with SLI and normalized-SSD had significantly higher ADHD inattentive ratings than the other subgroups. A proposed explanation for this interaction is discussed.  相似文献   

14.
DeCaro et al. [DeCaro, M. S., Thomas, R. D., & Beilock, S. L. (2008). Individual differences in category learning: Sometimes less working memory capacity is better than more. Cognition, 107(1), 284-294] explored how individual differences in working memory capacity differentially mediate the learning of distinct category structures. Specifically, their results showed that greater working memory capacity facilitates the learning of novel category structures that are verbalisable and discoverable through logical reasoning processes. Conversely, however, greater working memory was shown to impede the learning of novel category structures thought to be non-verbalisable, inaccessible to conscious reasoning and discoverable only through implicit (procedural) learning of appropriate stimulus-category responses. The present paper calls into question the specific nature of the category learning tasks used, in particular their ability to discriminate between different modes of category learning.  相似文献   

15.
    
Environmental context can have a profound influence on the efficacy of intervention protocols designed to eliminate undesirable behaviors. This is clearly seen in drug rehabilitation clinics where patients often relapse soon after leaving the context of the treatment facility. A similar pattern is commonly observed in controlled laboratory studies of context-dependent savings in instrumental conditioning, where simply placing an animal back into the original conditioning chamber can renew an extinguished instrumental response. Surprisingly, context-dependent savings in human procedural learning has not been carefully examined in the laboratory. Here, we provide the first known empirical demonstration of context-dependent savings in a perceptual categorization task known to recruit procedural learning. We also present a computational account of these savings using a biologically detailed model in which a key role is played by cholinergic interneurons in the striatum.  相似文献   

16.
Learning to avoid danger by observing others can be relatively safe, because it does not incur the potential costs of individual trial and error. However, information gained through social observation might be less reliable than information gained through individual experiences, underscoring the need to apply observational learning critically. In order for observational learning to be adaptive it should be modulated by the skill of the observed person, the demonstrator. To address this issue, we used a probabilistic two-choice task where participants learned to minimize the number of electric shocks through individual learning and by observing a demonstrator performing the same task. By manipulating the demonstrator’s skill we varied how useful the observable information was; the demonstrator either learned the task quickly or did not learn it at all (random choices). To investigate the modulatory effect in detail, the task was performed under three conditions of available observable information; no observable information, observation of choices only, and observation of both the choices and their consequences. As predicted, our results showed that observable information can improve performance compared to individual learning, both when the demonstrator is skilled and unskilled; observation of consequences improved performance for both groups while observation of choices only improved performance for the group observing the skilled demonstrator. Reinforcement learning modeling showed that demonstrator skill modulated observational learning from the demonstrator’s choices, but not their consequences, by increasing the degree of imitation over time for the group that observed a fast learner. Our results show that humans can adaptively modulate observational learning in response to the usefulness of observable information.  相似文献   

17.
    
Difficulties in math are the most frequently reported area of academic deficit in survivors of acute lymphoblastic leukemia (ALL) and the most frequent academic complaint among parents of ALL survivors. However, previous studies that included measures of math skills have been limited by the use of only a single measure of math skills, most often a measure of written calculations, without any assessment of math reasoning or math application skills. Further, the nature of these math difficulties has not been adequately investigated. The purpose of this study was to examine the performance of ALL survivors using multiple measures of math skills. Performance was compared to a group of healthy controls matched for age and sex as well as to normative levels. Other measures of neuropsychological function were also administered, and the relationships between these measures and the math measures were explored. Converging evidence for math difficulties in ALL survivors compared to healthy controls and normative levels was found. While ALL survivors generally performed within the average range on measures of math skills, math performance was mostly related to memory function and dominant-hand psychomotor speed. By contrast, math performance of healthy children was mostly related to basic reading skills and visual-motor integration. These findings shed light on the nature of math difficulties in ALL survivors and have implications for intervention.  相似文献   

18.
Although children with language impairments, including those associated with reading, usually demonstrate deficits in phonological processing, there is minimal agreement as to the source of those deficits. This study examined two problems hypothesized to be possible sources: either poor auditory sensitivity to speech-relevant acoustic properties, mainly formant transitions, or enhanced masking of those properties. Adults and 8-year-olds with and without phonological processing deficits (PPD) participated. Children with PPD demonstrated weaker abilities than children with typical language development (TLD) in reading, sentence recall, and phonological awareness. Dependent measures were word recognition, discrimination of spectral glides, and phonetic judgments based on spectral and temporal cues. All tasks were conducted in quiet and in noise. Children with PPD showed neither poorer auditory sensitivity nor greater masking than adults and children with TLD, but they did demonstrate an unanticipated deficit in category formation for nonspeech sounds. These results suggest that these children may have an underlying deficit in perceptually organizing sensory information to form coherent categories.  相似文献   

19.
    
This study examined the contribution of verbal and visual memory to performance on the Family Pictures subtest of the Children’s Memory Scale. This subtest purports to assess declarative memory functioning in the visual/nonverbal domain. A total of 115 nine-year-old children participated in this study. Fifty-eight had specific language impairment (SLI), whilst the remaining 57 were typically developing (TD), with no history of language difficulties. Results showed that the children with SLI, who had intact declarative memory for visual but not verbal information, obtained significantly lower scores on the Family Pictures subtest when compared to the TD group. Regression analyses revealed that across the entire sample, individual differences on the Family Pictures subtest was best predicted by a measure of verbal working memory. These results question whether the Family Pictures subtest can be considered a measure of visual memory in pediatric populations. These results have implications for the interpretation of scores on this subtest regarding the nature of the types of neurocognitive difficulties children may exhibit.  相似文献   

20.
The ability to seriate nesting cups as a sensorimotor task has posed interesting questions for cognitive scientists. Greenfield et al. [(1972) Cognit Psychol 3:291–310] found parallels between children's combinatorial activity with nesting cups and patterns of phonological and grammatical constructions. The parallels suggested the possibility of a neurally based developmental homology between language and instrumental action [Greenfield (1991) Behav Brain Sci 14:531–595]. Children who predominantly used subassembly, a hierarchical method of combining cups, succeeded at seriating nesting cups more often than those who did not. Greenfield and others [e.g., Piaget and Inhelder (1969) The psychology of the child. Basic Books, New York; DeLoache et al. (1985) Child Dev 56:928–939] argued that success in seriation reflects the child's growing recognition of a reversible relationship: a particular element in a series is conceived of as being smaller than the previous element and larger than the subsequent element. But is a concept of reversibility or a hierarchical form of object manipulation necessary to seriate cups? In this article, we review studies with very young children and nonhuman primates to determine how individuals that do not evidence conceptual reversibility manage the seriation task. We argue that the development of skill in seriation is experientially, rather than conceptually, driven and that it may be unnecessary to link seriation with cognitive conceptions of reversibility or linguistic capacities. Rather, in ordering a set of objects by size, perceptual-motor learning may enable contemplative refinement. Accepted after revision: 10 September 2001 Electronic Publication  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号