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911.
912.
An experiment was conducted to investigate the generalizability of Rachman's match/mismatch model and to explore if environmental conditions affect the consequences of an underprediction. Twenty subjects walked around in agoraphobic, and 15 did so in neutral, situations. Both groups carried a walkman and 7 aversive human screams were administered to them at random times. The results gave strong support to previous investigations on matches and mismatches, but no differences were shown between agoraphobic and neutral situations. Possible explanations are discussed.  相似文献   
913.
In an experiment with handwriting tasks effects of phonological and motoric task factors upon reaction time and movement time were measured to test implications of a discrete information processing account of the task. The model is built up of serially organized stages, each of which monitors one specific type of operation, necessary to generate a message. The serial structure of the model is defined as the limitation that higher levels of the model provide their output to the next lower processor in the hierarchy, and receive their input from the next higher stage. The parallel character of the model is exemplified through the assumption that all processors are active at the same time and concurrently with the real time production of writing movements. The study adds evidence that a serial architecture of processors can be compatible with the parallel processing of a message as long as more abstract operations are prepared more in advance to real-time movements than operations lower in the hierarchy. In the experiment the prediction was tested that the time course of the manifestation of phonological and motoric task demands reflects the discrete and serial structure of the model.  相似文献   
914.
Tracking performance was investigated in children (aged 6-7 and 10-11) and in adult subjects. Target signals, moving unpredictably along a straight line, were tracked with the preferred arm, alternately with and without visual feedback. Qualitative observations indicate that tracking is based on continuous adjustments of the ongoing response to the continuously changing target position. No step-and-hold strategy could be detected in any of the three age groups. Tracking performance was described with four simple parameters, derived from linear systems analysis: (a) the delay between target signal and tracking movement (DL); (b) performance at the low-frequency range (LF), (c) performance at the high-frequency range (HF); and (d) a measure of tracking quality or overall similarity in the shape of target signal and tracking movement (Q). There was a considerable improvement in tracking performance with age, even after the age of 10-11, which was mainly demonstrated by a decrease in DL and increases in HF and Q. Tracking performance decreased only to a small extent when visual feedback was withdrawn. Age-related differences in the contribution of visual feedback to tracking performance could not be demonstrated.  相似文献   
915.
A perceptual identification task was used to provide an implicit measure for automatic memory processes. The facilitation of word identification on repeated presentation is taken as a measure of the automatic retrieval of an episode. In addition, recognition memory was tested. The recognition task is an explicit test of memory and relies mainly on controlled processing. In the first experiment 11 patients suffering from probable Alzheimer disease and 11 normal age- and sex-matched controls were tested. Both groups exhibited a rather small facilitation effect (ca 7%) but did not differ in the size of the effect. However, when tested explicitly, a difference in recognition memory existed between the two groups. In the second experiment the performance of 11 normal young subjects was compared to that of 11 normal elderly subjects. Whereas the elderly group showed a small facilitation effect similar to that observed in the first experiment, a considerable facilitation effect was found for the young group. Also, the elderly group had poorer recognition memory than the young group.  相似文献   
916.
Van Lohuizen’s ideal of unity, must above all be seen as a challenge to attain the necessary integration of planning, research, and design to meet the requirements of a changing society. Though Van Lohuizen's ideas were influenced strongly by the rational and technical principles of the CIAM, he saw technology as a means to an end in an approach that is primarily based on humans and culture. In the ideas of Van Lohuizen, different dimensions can be traced. New developments in these dimensions are discussed in the article. There is no lack of innovative ideas and methods. Nearly all the ideas and methods discussed were developed in the forties, fifties, or sixties. On the basis of the incubation period required for introduction on a wider scale, it is now time for them to find greater favor with society. Following the years of a no-nonsense policy, it seems that in many fields there is a new need for a wider, more qualitative approach. Ron van Eck studied architecture and management research at the University of Technology of Delft. He is working at the RIW—Research Institute of the Department of Architecture at the University of Technology of Delft, and at the Network for Spatial Organisation in Amsterdam.  相似文献   
917.
The smoking attitudes and behavior of two samples of British 15-year-olds (N = 278) were studied by questionnaire. “Smokers” (anyone who had smoked at all within the previous week) held less negative attitudes about smoking, were more likely to have a father who smoked, and anticipated less parental disapproval of their smoking. When asked to name their five best friends among their classmates, smokers were more likely to name other smokers than were nonsmokers. On the basis of these results, we argue that the notion of “peer group influence” should be reconceptualized in terms of intergroup processes and social identity concerns within the peer group.  相似文献   
918.
The motor programming of fast goal-directed arm movements was studied in a tracking task. A target jumped once or twice randomly to the left or right direction with an interstimulus interval (ISI) in a range between 50 and 125 msec. Double step stimuli were either two steps in the same direction (C-trial) or in opposite direction (R-trial). Tracking results show that at the beginning average EMG-activity is the same for responses to single step trials, R-trials and C-trials. Differences set in after some time equal to or somewhat shorter than ISI. It was concluded that muscle activation patterns of fast goal-directed movements are not preprogrammed but that they can be modified during the movement. The time interval between second target step and the moment when EMG activity of the double step response deviates from the EMG activity of a single step (RT2) could be smaller than the time interval between first target displacement and EMG onset. (RT1). If modification of the muscle activation pattern required a longer or larger activation of the active muscle, RT2 tended to be smaller than RT1, whereas RT2 was about equal to RT1 if the new muscle activation required a termination of the ongoing muscle activation pattern and the activation of another muscle.  相似文献   
919.
Children referred with specific reading dysfunction were subtyped as accuracy disabled or rate disabled according to criteria developed from an information processing model of reading skill. Multiple measures of oral and written language development were compared for two subtyped samples matched on age, sex, and IQ. The two samples were comparable in reading fluency, reading comprehension, word knowledge, and word retrieval functions. Accuracy disabled readers demonstrated inferior decoding and spelling skills. The accuracy disabled sample proved deficient in their understanding of oral language structure and in their ability to associate unfamiliar pseudowords and novel symbols in a task designed to simulate some of the learning involved in initial reading acquisition. It was suggested that these two samples of disabled readers may be best described with respect to their relative standing along a theoretical continuum of normal reading development.  相似文献   
920.
Ultrasound technology has not been used extensively in the study of normal and abnormal oral physiology and speech. Features such as soft tissue detail, real-time motion display, and subject safety make ultrasound ideal for imaging the tongue and the floor of the mouth. This study demonstrates visualization of the muscles of the tongue and floor of the mouth for a normal subject using ultrasound imaging. By employing submandibular transducer placement of real-time sector scanners, tongue anatomy and motion were continuously visualized in sagittal or coronal planes. In addition to the entire tongue surface, much of the intrinsic anatomy was identified including: the genioglossus, geniohyoid, mylohyoid, and digastric muscles; fascial boundaries such as the median fibrous septum, floor intermuscular septum, and paramedian septums; and the hyoid bone. A tongue excised from a human cadaver was scanned using ultrasound and dissected to confirm the anatomy seen in the live tongue. Tongue surface shape and configuration of the intrinsic tissue structures were observed and compared for the phonemes /k/, /u/, and /i/. Anatomical landmarks in the resting and speaking tongue are discussed as well as applications in the fields of speech science and speech pathology.  相似文献   
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