自闭症儿童视觉动态信息的注意加工特点——来自多目标追踪任务的证据

为了考察中低功能自闭症儿童在动态条件下的多目标注意加工特点,研究采用多目标追踪实验范式,具体追踪任务采用多目标随机运动和碰撞反弹算法。实验设计为两因素混合设计,组间变量为年龄和性别匹配的中低功能自闭症和正常儿童组,组内变量为追踪目标数量（分别为1、2、3、4个目标）,因变量为被试在多目标追踪任务中的追踪正确率和追踪容量。结果发现：（1）中低功能自闭症儿童在目标数量为1到目标数量为4时的正确率均明显低于正常儿童,且标准差变异较大,中低功能自闭症儿童的多目标的持续追踪能力和稳定性存在一定的缺陷;（2）当目标数量为1时,正常组儿童与中低功能自闭症儿童的追踪容量差异不显著;目标为2、3、4时,两组追踪容量差异均显著。不同目标数量情况下中低功能自闭症儿童平均的注意容量为0.83~1.24个（平均容量约为1个）明显低于正常儿童的0.95~3.72个（最大容量接近4个）。中低功能自闭症儿童在多目标追踪上表现为单焦点注意加工的特点,存在一定程度的注意转移缺陷。     

Favourite objects of autistic children

Favourite objects (FOs) of autistic children were compared with the FOs of healthy preschool and school children as well as mentally handicapped children. Three clusters of objects were obtained for normal children (comprising primary transitional objects and their forerunners, secondary transitional objects, and non-cuddly toys). When autistic children and mentally handicapped children were included, a fourth cluster of deviant objects was found. Frequency distributions of the two handicapped groups in the clusters were similar. Similarities between the two handicapped groups were also found within each cluster. The occurrence of secondary transitional objects was rare in the handicapped groups. The characteristics of "autistic" FOs reported in earlier case studies (e.g. being hard, often having an exciting effect, not being used in their adequate functions) were typical only of objects in the fourth cluster.     

Evidence for language recoding in autistic, retarded and normal children: a re-examination

In a replication and extension of earlier studies by Hermelin & O'Connor, language recoding abilities in autistic, retarded and normal children matched for mental age and digit span, were compared in a verbal recall task. Random word lists, sentences, and anomalous sentences, eight or 12 items in length (for high and low memory span subgroups) were presented and the number of words recalled from each type of input was scored. All low span children recalled sentences better than random lists with normal children superior to retarded and autistic children and the latter group poorer than the retarded group. Autistic children showed a recency effect with both types of input. There were no group differences amongst high span children and sentences were again better recalled than random lists. In Expt II sentences were better recalled than anomalous sentences, with autistic and retarded children equivalent in performance and poorer than normal children. Although low span autistic children were clearly deficient in recall of sentence material when compared with the two control groups, the effect of conditions showed that they were able to use structure to improve recall. Since high span autistic children did not perform differently from controls it is suggested that results from this kind of study may not be generalizable, and that claims for a specific coding deficit in autistic children need further substantiation.     

The generality of overselectivity in developmentally disabled children

A growing body of research suggests that low Mental Age (MA) autistic and retarded children show a unique stimulus control deficit, one that may cause many or most of their behavioral deficiencies. This problem, stimulus overselectivity, is evidenced when a child responds only to a restricted portion of the stimulus environment when compared with normal children. The purpose of this study was to assess whether this overselectivity is general across situations or whether it is restricted to certain stimulus/task conditions. Eight autistic children, who evidenced overselectivity on a preassessment task, and 8 normal children with similar MA levels participated. All children were trained on 3 tasks to determine if overselectivity varied as a function of different stimulus conditions. Each of the 3 tasks involved training a child to respond to (i.e., touch) a card containing a circle (S +) and to avoid a blank (S ?) card. In each case, the circle comprised a series of dots. The difference between the 3 circles (tasks) was the distance between the successive dots making up each circle. Also, in the minimal separation condition the dots were smaller in size and greater in number than in the larger separation conditions. Of concern was whether autistic children learned about the gestalt (i.e., the circle), which required attention to multiple cues, or whether children would overselect and respond to the dots. The results showed that (1) stimulus overselectivity was found not to be a generalized deficit in autistic subjects; instead, it varied as a function of the stimulus variables; and (2) the stimulus variables manipulated in this study similarly influenced the responding of both normal and autistic children. The implications of these data for a theory of overselectivity are discussed.     

TEACHING FUNCTIONAL COMMUNITY SKILLS TO AUTISTIC CHILDREN USING NONHANDICAPPED PEER TUTORS

In this study, two autistic children were paired with normal peers who, after pretraining sessions, taught community skills to the autistic children. Data were collected during three conditions: baseline, modeling, and peer tutoring. Results demonstrated that no identified skills were acquired during the baseline and modeling conditions. However, direct instruction of each child by a peer tutor resulted in the learning and maintenance of functional community skills.     

Teaching autistic children to respond to simultaneous multiple cues

A number of studies have shown that autistic children tend to learn new discriminations by responding to only a restricted number of available cues and that this may be responsible for some of their abnormal behavior. Therefore, this investigation assessed the feasibility of teaching autistic children to respond to multiple cues. The results showed that four autistic children could learn a conditional discrimination requiring them to discriminate a multiple-cue complex from each of its two component cues. However, the autistic children did not learn this discrimination in the same manner as normal children. In the early trials, the autistics responded at a higher level to one of the two component cues. Only after many trials did the autistics respond equally on the basis of both component cues. The results of an initial attempt to teach a general set to respond to multiple cues showed that, when an autistic child was taught a series of successive conditional discriminations, the child eventually learned a set to approach new discriminations by responding equally on the basis of both component cues. The results are discussed in terms of understanding and treating autistic children's abnormal development.     

NORMAL PEER MODELS AND AUTISTIC CHILDREN'S LEARNING

Present research and legislation regarding mainstreaming autistic children into normal classrooms have raised the importance of studying whether autistic children can benefit from observing normal peer models. The present investigation systematically assessed whether autistic children's learning of discrimination tasks could be improved if they observed normal children perform the tasks correctly. In the context of a multiple baseline design, four autistic children worked on five discrimination tasks that their teachers reported were posing difficulty. Throughout the baseline condition the children evidenced very low levels of correct responding on all five tasks. In the subsequent treatment condition, when normal peers modeled correct responses, the autistic children's correct responding increased dramatically. In each case, the peer modeling procedure produced rapid achievement of the acquisition criterion which was maintained after the peer models were removed. These results are discussed in relation to issues concerning observational learning and in relation to the implications for mainstreaming autistic children into normal classrooms.     

A comparison of hemispheric asymmetries in speech-related brain potentials of autistic and dysphasic children

In a previous study (G. Dawson, C. Finley, S. Phillips, & L. Galpert, 1986, Child Development, 57, 1440-1453) it was found that measures of hemispheric asymmetry during speech processing were predictive of level of language ability in autistic children. The purpose of the present study was to determine whether a similar relationship between pattern of hemispheric asymmetry and language ability exists for language-impaired children without autism. Ten autistic children (8-13 years), 10 dysphasic children (6-15 years), and 10 normal children (8-13 years) were compared in terms of their patterns of hemispheric asymmetry in the averaged cortical evoked response to a simple speech stimulus, and the relationship between pattern of hemispheric asymmetry and language ability was assessed for each clinical group. It was found that, for both the autistic and dysphasic groups, the majority of subjects showed a reversed direction of hemispheric asymmetry from that characteristic of the normal group. A strong relationship between pattern of asymmetry and level of language ability was found for autistic subjects; autistic subjects with more severe language impairments were more likely to show reversed asymmetry than subjects with less severe language impairments. In contrast, no relationship between language ability and direction of hemispheric asymmetry in the evoked response was found for dysphasic subjects. Separate analyses of right and left hemisphere evoked responses indicated that language ability was related to right hemisphere activity for autistic subjects, and to left hemisphere activity for dysphasic subjects.     

表情强度对自闭症儿童面部表情识别影响的实验研究

为探寻自闭症儿童在识别低强度（10%,30%）、中强度（40%,60%）和高强度（70%,90%）的愤怒和开心面部表情时,识别情绪类型的既有能力和差异。采用表情标签范式,用E-prime软件在电脑上呈现不同强度的3D合成面部表情刺激,分别对10名自闭症儿童、10名正常发育儿童和10名智障儿童进行了实验研究。结果发现,自闭症儿童在低强度表情时具有面部表情识别障碍,其对不同强度面部表情识别正确率显著低于智障儿童和正常发育儿童;自闭症儿童面部表情识别正确率与面部表情强度呈正相关,面部表情强度越大,自闭症儿童面部表情识别的正确率越高;自闭症儿童对低强度面部表情识别时,对开心表情的识别正确率高于愤怒表情,但是,在中强度和高强度面部表情识别时,存在显著的愤怒优势效应。     

自闭症儿童的中心信息整合及其与心理理论的关系

研究用积木测验和镶嵌图形测验测量中心信息整合,用5个信念任务测量心理理论能力,比较了12名自闭症儿童和同等言语能力的28名正常儿童的表现,并分析了心理理论和中心信息整合的相关。结果表明:(1)中心信息整合的测量指标积木测验和镶嵌图形测验成绩保持中高度相关;(2)自闭症儿童中心信息整合显著弱于正常儿童;(3)心理理论和中心信息整合成绩相互独立。     

Overselectivity,developmental level,and overtraining in autistic and normal children

Thirteen autistic children were compared to 13 normal children, matched to them in mental age, on performance of a visual discrimination task. Form, color, and size were relevant and redundant cues. The groups did not differ significantly in mean trials to reach criterion or in breadth of learning, and both groups increased their breadth of learning after 50 trials of overtraining. Form was preferred to color and size by both autistic and normal children. Within each group, rank on mental age was highly correlated with rank in breadth of learning. Verbal and nonverbal autistic children did not differ in breadth of learning or in dimensional preference. Even nonverbal autistics equaled the performance of their normal controls. Our results suggest that overselective attention is better understood as part of a general developmental lag in cognition in autistic children than as a specific deficit underlying psychotic behavior.This research was supported in part by NIMH Grant 11440, O. I. Lovaas, principal investigator. The authors thank Dr. Lovaas and Dennis C. Russo for their helpful criticisms of an earlier draft.     

Caregiver interactions with autistic children

Caregiver interactions with young autistic children were contrasted with those involving caregivers and developmentally matched mentally retarded and normal infants. Caregivers of autistic children were similar to other caregivers in their responsiveness to child nonverbal communication bids and in their engagement in mutually sustained play. Caregivers of autistic children were similar to caregivers of mentally retarded children in their greater use of control strategies. However, these two groups of caregivers differed in the particular strategies they used to shape their children's behavior. Caregivers of mentally retarded children pointed to objects while caregivers of autistic children spent more time physically holding their children on task. Individual differences within the autistic sample indicated that caregivers regulated their children's behavior less and showed more mutual play and positive feedback to more communicatively able autistic children. These findings suggest that caregivers respond differentially to the specific deficiencies shown by their children.     

The scaling of postural adjustments during bimanual load-lifting in traumatic brain-injured adults

Previous postural studies of traumatic brain injury (TBI) patients have been limited to identifying deficits in static and quasi-dynamic postural control tasks such as weight shifting. In this study, we examined whether or not patients with TBI are able to scale adequately their postural adjustments during the performance of the dynamic task of bimanual load-lifting. An age matched group of healthy adults served as controls. We used the Tetrax posturography system that calculates a stability score (ST) based on fluctuations in vertical ground reaction forces, normalized for body weight. During quiet standing, the ST scores of the TBI group were significantly higher than the control group. Forward weight shift and percentage change in the vertical ground reaction forces (lift postural adjustment (LPA) and post-lift postural adjustment (PLPA) scores) linearly increased with increasing load weight in both healthy and TBI subjects. Group differences were found in the magnitude of forward weight shift but not in the relative increase of the LPA and PLPA scores during the lifting and post-lifting phases respectively. The forward weight shift of the TBI group was lower-than-normal and asymmetrical--there was significantly less forward weight shift on the more affected than on the less affected limb. In addition, a significant amplitude coupling was found between the scaling of the weight shift of the heel and forefoot of each limb. However, no coupling was found between the weight shift amplitudes of homologous parts of both limbs in the TBI group. The results showed that scaling based on prior experience was preserved in the TBI group, though some TBI subjects demonstrated absent scaling in either the more affected or less affected heel or forefoot. The differences between the normal and TBI groups in postural adjustments are not necessarily a sign of pathology; rather they may represent a deliberate choice of the central nervous system to counteract predictable disturbances.     

Advancing age progressively affects obstacle avoidance skills in the elderly

The ability to adequately avoid obstacles while walking is an important skill that allows safe locomotion over uneven terrain. The high proportion of falls in the elderly that is associated to tripping over obstacles potentially illustrates an age-related deterioration of this locomotor skill. Some studies have compared young and old adults, but very little is known about the changes occurring within different age groups of elderly. In the present study, obstacle avoidance performance was studied in 25 young (20-37 years) and 99 older adults (65-88 years). The participants walked on a treadmill at a speed of 3 km/h. An obstacle was dropped 30 times in front of the left foot at various phases in the step cycle. Success rates (successful avoidance) were calculated and related to the time available between obstacle appearance and the estimated instant of foot contact with the obstacle (available response times or ARTs ranging from 200 to more than 350 ms). In addition, latencies of avoidance reactions, the choice of avoidance strategies (long or short step strategy, LSS or SSS), and three spatial parameters related to obstacle avoidance (toe distance, foot clearance, and heel distance) were determined for each participant. Compared to the young, the older adults had lower success rates, especially at short ARTs. Furthermore, they had longer reaction times, more LSS reactions, smaller toe and heel distances, and larger foot clearances. Within the group of elderly, only the 65-69 year olds were not different from young adults with respect to success rate, despite marked changes in the other parameters measured. In particular, even this younger group of elderly showed a dramatic reduction in the amount of SSS trials compared to young adults. Overall, age was a significant predictor of success rates, reaction times, and toe distances. These parameters deteriorated with advancing age. Finally, avoidance success rates at short ARTs were considerably worse in elderly participants who sustained recurrent falls in the six-month period prior to the assessment compared to those who sustained no or only one fall. An exercise program has been shown to improve avoidance success rates, especially at short ARTs, but the training effects on the determinants of success still need to be assessed.     

Selective responding to the components of multiple visual cues by autistic children

Fifteen autistic and 15 normal Ss were trained to respond to a card containing two visual cues. After this training disctimination was established, the children were tested on the single cues in order to assess whether one or both stimuli had acquired control over their responding. The autistic children (12 of 15) gave evidence for stimulus overselectivity in that they responded correctly to only one of the two component cues. On the other hand, the normal children (12 of 15) showed clear evidence of control by both component cues of the training card. These results were consistent with previous studies, where autistics showed overselectivity when presented with multiple sensory input in several modalities. However, now autistic children appear to have difficulty responding to multiple cues even when both cues are in the same modality. These results were discussed in relation to the experimental literature on selective attention in normally functioning organisms.     

Application of a simple recording system to the analysis of free-play behavior in autistic children

An observational system, which has been developed to facilitate recording of the total behavioral repertoire of autistic children, involves time-sampling recording of behavior with the help of a common Stenograph machine. Categories which exhausted all behavior were defined. Each category corresponded with a designated key on the Stenograph machine. The observer depressed one key at each 1-sec interval. The observer was paced by audible beats from a metronome. A naive observer can be used with this method. The observer is not mechanically limited and a minimum of observer training is required to obtain reliable measures. The data sampled during a five-week observation period indicated the stability of a taxonomic instrument of behavior based upon direct, time-sampling observations and the stability of spontaneous autistic behavior. Results showed that the behavior of the subjects was largely nonrandom and unsocialized in character.     

Perceptibility of large and sequential changes in somatosensory information during leaning forward and backward when standing

11 healthy young men served as subjects in two experiments on perceptibility of (1) large changes in foot pressure and muscle activity induced by body leaning and (2) sequential changes in pressure at the first toe and the head of the first metatarsalis when leaning forward. The effects of reduced sensitivity on that perceptibility were also studied by repeating the experiments while cooling localized plantar areas of the sole (the head of the first metatarsalis, the first toe, and the heel). Under the normal (noncooled) condition, all subjects accurately perceived maximum pressure at the head of the first metatarsalis, but most subjects misperceived the second large increase in pressure at the first toe and in muscle activity as the first large increase. Under the cooling condition, localized cooling did not affect the perceptibility of maximum pressure at the head of the first metatarsalis or the activity in the tibialis anterior, but the perceptibility of pressure at the first toe and activity of the abductor hallucis were reduced. There were individual differences in perceptibility of activity of the rectus femoris when the heel was cooled. Perceptibility of sequential changes in the pressure was affected differently by the localized cooling of each region. Given these findings, we discussed the role and interrelatedness of pressure sensation in perceiving large and sequential changes in somatosensory information while standing and leaning forward and backward.     

Affective exchanges between young autistic children and their mothers

This study examined autistic children's social behavior, affect, and use of gaze during naturalistic interactions with their mothers. Sixteen autistic children, 30 to 70 months of age, and 16 normal children, matched on receptive language, participated. Children and their mothers were videotaped during three situations: a free-play period, a more structured period during which communicative demand was made on the child, and a face-to-face interaction. In all three situations, autistic and normal children did not differ in the frequency or duration of gaze at mother's face. In the one condition (face-to-face interaction) during which affective expressions were coded, autistic and normal children also were not found to differ significantly in the frequency or duration of smiles displayed, and neither group displayed frowns. However, autistic children were much less likely than normal children to combine their smiles with eye contact in a single act that conveyed communicative intent. Autistic and normal children were not found to differ in the percentages of smiles they displayed to social versus nonsocial events. However, when autistic children's responses to mother's smiles specifically were examined, it was found that they were much less likely to smile in response to mother's smiles than were normal children. Finally, it was found that mothers o f autistic children displayed fewer smiles and were less likely to smile in response to their children's smiles, when compared with mothers o f normal children. These findings suggest that the autistic child's unusual affective behavior may negatively affect the behavior of others.We wish to thank the children and their mothers who participated in this study, and the staff at Division TEACCH at the University of North Carolina at Chapel Hill for their help in recruiting children for the study. Harriet Reingold generously allowed us to videotape the children in her infant observation laboratory at the University of North Carolina, Chapel Hill. Cathy Lord provided videotapes of some of the autistic children and their mothers. Mary Evers assisted in data collection. Kerry Hogan assisted in the coding of data; her help is gratefully acknowledged. The study was supported by a grant from the University of North Carolina at Chapel Hill.     

自闭症幼儿的情感认知特点的实验研究

本实验采用3(组别)×4(基本情绪)×3(实验材料)×2(实验条件)的混合设计的方法对平均心理年龄24个月的6名自闭症幼儿和心理年龄与之相近的6名正常儿童和6名弱智儿童的情感认知特点进行了比较性的研究。实验结果表明:在“语言提示”条件下,自闭症幼儿的正答率远远低于正常儿童和弱智儿童,但在“表情提示”条件下,自闭症幼儿与弱智幼儿几乎没差距,在对“愤怒”和“惊恐”等情绪的认知中,正答率高于弱智幼儿。这意味着自闭症幼儿可能运用了其他的替代策略进行情感认知。     

自闭症儿童依恋研究述评

摘要　　研究者曾一度认为自闭症儿童无法建立起依恋关系。本文系统回顾了自闭症儿童依恋研究的最新进展,将自闭症儿童是否存在依恋行为（尤其是安全型依恋行为）、依恋发展解释理论、研究方法、类型分布以及影响因素等问题进行了详细梳理,并结合研究分析,提出有关自闭症儿童依恋研究的几点启示,以供参考。