Linguistic cues enhance the learning of perceptual cues.
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When language is correlated with regularities in the world, does it enhance the learning of these regularities? This question lies at the core of both notions of linguistic bootstrapping in children and the Whorfian hypothesis. Support for an affirmative answer is provided in an artificial-noun-learning task in which 2-year-old children were taught to distinguish categories of solid and nonsolid things with and without supporting correlated linguistic cues. (+info)
Effects of reverberation time on the cognitive load in speech communication: theoretical considerations.
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The paper presents a theoretical analysis of possible effects of reverberation time on the cognitive load in speech communication. Speech comprehension requires not only phonological processing of the spoken words. Simultaneously, this information must be further processed and stored. All this processing takes place in the working memory, which has a limited processing capacity. The more resources that are allocated to word identification, the fewer resources are therefore left for the further processing and storing of the information. Reverberation conditions that allow the identification of almost all words may therefore still interfere with speech comprehension and memory storing. These problems are likely to be especially serious in situations where speech has to be followed continuously for a long time. An unfavourable reverberation time (RT) then could contribute to the development of cognitive fatigue, which means that working memory resources are gradually reduced. RT may also affect the cognitive load in two other ways: RT may change the distracting effects of a sound and a person's mood. Both effects could influence the cognitive load of a listener. It is argued that we need studies of RT effects in realistic long-lasting listening situations to better understand the effect of RT on speech communication. Furthermore, the effect of RT on distraction and mood need to be better understood. (+info)
Children's cognition and aircraft noise exposure at home--the West London Schools Study.
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The association of aircraft noise exposure with cognitive performance was examined by means of a cross-sectional field survey. Two hundred thirty six children attending 10 primary schools around Heathrow Airport in west London were tested on reading comprehension, immediate/delayed recall and sustained attention. In order to obtain the information about their background, a questionnaire was delivered to the parents and 163 answers were collected. Logistic regression models were used to assess performance on the cognitive tests in relation to aircraft noise exposure at home and possible individual and school level confounding factors. A significant dose-response relationship was found between aircraft noise exposure at home and performance on memory tests of immediate/delayed recall. However there was no strong association with the other cognitive outcomes. These results suggest that aircraft noise exposure at home may affect children's memory. (+info)
Reading skills after left anterior temporal lobe resection: an fMRI study.
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Maintaining language functions after left hemisphere lesions has been associated with compensatory right hemisphere activation. It remains unclear whether recruitment of right hemisphere regions necessarily provides an effective mechanism to compensate for language deficits. To investigate the compensatory mechanisms that mediate good reading skills in patients after left anterior temporal lobe resection for mesial temporal lobe epilepsy (mTLE), we tested for the effect of their reading ability on the regional fMRI (functional MRI) signal elicited by sentence reading. Sixteen control subjects and 16 patients participated in the study. In the activation condition, they silently read nine-word sentences, and in the baseline condition they viewed nine-word sentences after all the letters were transformed into false fonts. Reading ability in controls and patients significantly (P < 0.05, corrected) predicted activations in a left hemisphere middle temporal region that was part of the normal sentence reading system. In addition, reading ability in patients, but not controls, significantly predicted activation in the right inferior frontal sulcus, right hippocampus and right inferior temporal sulcus. Right inferior frontal activation was only observed in the patients. In contrast, right hippocampal and inferior temporal activation was observed in all controls and in patients whose reading ability was within the normal range, indicating the importance of these regions for efficient encoding during normal sentence reading. We conclude that proficient reading skills following left anterior temporal lobe resection for mTLE rely on two mechanisms: (i) integrating regions from the normal system (i.e. the left middle temporal, right hippocampus and anterior superior temporal sulcus); and (ii) recruiting right hemisphere regions (i.e. the right inferior frontal sulcus) that are not activated in control subjects. (+info)
Public opinion and purchasing.
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OBJECTIVES: To explore the use of a questionnaire to obtain representative public opinions on health services. To examine residents' priorities, knowledge, and views on the public's role in decision making. DESIGN: Self administered postal questionnaire. POPULATION: Random sample of 1500 residents in Bath District Health Authority, drawn from electoral registers. MAIN OUTCOME MEASURES: Levels of agreement or disagreement with statements provided and degree of importance given to services and aspects of services. RESULTS: 70 questionnaires were returned unopened. Completed questionnaires were returned by 704 (49.2%) of the 1430 remaining residents. Kidney dialysis was thought very important by 559 (87%) respondents and family planning by only 58 (9%). Public priorities did not seem to reflect value for money. Clear information about treatment was rated as very important by 530 (76%) and comfortable waiting areas by 70 (10%). 372 (53%) of respondents said that they would definitely travel to a hospital outside the district to reduce their wait for surgery. Knowledge of the services provided by the authority and the money available to it was poor. 446 (65%) respondents wanted greater public involvement in decision making. CONCLUSIONS: A postal questionnaire can provide useful information about public priorities and perceptions about the services provided. More information about health services and their costs and benefits should be given to the public to assist greater public participation in decision making. (+info)
Sign and speech: amodal commonality in left hemisphere dominance for comprehension of sentences.
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The neural basis of functional lateralization in language processing is a fundamental issue in systems neuroscience. We used functional MRI (fMRI) to examine hemispheric dominance during the processing of signed and spoken sentences. By using tasks involving comprehension of sentences (Sc) and sentential non-word detection (Sn), we compared different groups and stimulus conditions. Under the sign condition with sentence stimuli in Japanese Sign Language (JSL), we tested two groups of subjects: Deaf signers (Deaf) of JSL, and hearing bilinguals (children of Deaf adults, CODA) of JSL and Japanese (JPN). Under the speech condition, we tested hearing monolinguals (Mono) of JPN with auditory JPN stimuli alone (AUD), or with an audiovisual presentation of JPN and JSL stimuli (A&V). We found that the overall bilateral activation patterns under the four experimental conditions of Deaf, CODA, AUD and A&V were almost identical, despite differences in stimuli (JSL and JPN) and groups (Deaf, CODA and Mono). Moreover, consistently left-dominant activations involving frontal and temporo-parietal regions were observed across all four conditions. Furthermore, irrespective of the modalities of sign and speech, the main effects of task (Sc-Sn) were found primarily in the left regions: the ventral part of the inferior frontal gyrus (F3t/F3O), the precentral sulcus, the superior frontal gyrus, the middle temporal gyrus, the angular gyrus and the inferior parietal gyrus. Among these regions, only the left F3t/F3O showed no main effects of modality condition. These results demonstrate amodal commonality in the functional dominance of the left cortical regions for comprehension of sentences, as well as the essential and universal role of the left F3t/F3O in processing linguistic information from both signed and spoken sentences. (+info)
Grasping the intentions of others with one's own mirror neuron system.
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Understanding the intentions of others while watching their actions is a fundamental building block of social behavior. The neural and functional mechanisms underlying this ability are still poorly understood. To investigate these mechanisms we used functional magnetic resonance imaging. Twenty-three subjects watched three kinds of stimuli: grasping hand actions without a context, context only (scenes containing objects), and grasping hand actions performed in two different contexts. In the latter condition the context suggested the intention associated with the grasping action (either drinking or cleaning). Actions embedded in contexts, compared with the other two conditions, yielded a significant signal increase in the posterior part of the inferior frontal gyrus and the adjacent sector of the ventral premotor cortex where hand actions are represented. Thus, premotor mirror neuron areas-areas active during the execution and the observation of an action-previously thought to be involved only in action recognition are actually also involved in understanding the intentions of others. To ascribe an intention is to infer a forthcoming new goal, and this is an operation that the motor system does automatically. (+info)
Right hemisphere language functions and schizophrenia: the forgotten hemisphere?
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This review highlights the importance of right hemisphere language functions for successful social communication and advances the hypothesis that the core deficit in psychosis is a failure of segregation of right from left hemisphere functions. Lesion studies of stroke patients and dichotic listening and functional imaging studies of healthy people have shown that some language functions are mediated by the right hemisphere rather than the left. These functions include discourse planning/comprehension, understanding humour, sarcasm, metaphors and indirect requests, and the generation/comprehension of emotional prosody. Behavioural evidence indicates that patients with typical schizophrenic illnesses perform poorly on tests of these functions, and aspects of these functions are disturbed in schizo-affective and affective psychoses. The higher order language functions mediated by the right hemisphere are essential to an accurate understanding of someone's communicative intent, and the deficits displayed by patients with schizophrenia may make a significant contribution to their social interaction deficits. We outline a bi-hemispheric theory of the neural basis of language that emphasizes the role of the sapiens-specific cerebral torque in determining the four-chambered nature of the human brain in relation to the origins of language and the symptoms of schizophrenia. Future studies of abnormal lateralization of left hemisphere language functions need to take account of the consequences of a failure of lateralization of language functions to the right as well as the left hemisphere. (+info)