Patterns of maternal and infant imitation during play

In contrast to recent experimental studies that have sought to establish the infant's ability to imitate, the goal of the current study was to establish the actual performance of imitation by infants and their mothers during episodes of face-to-face play. Three-min play episodes of 20 mothers and their 13- to 16-week-old infants were videotaped. Instances of mouth openings, lip movements, tongue protrusions, smiling, and vocalizations by both partners were coded. Sequential analyses revealed stochastic patterns of imitation by both interactants. Mothers contingently imitated initiations by their infants and were more likely to make like initiations during action in the same category by their infants. Infants did not show onset-to-onset imitation but did show an increased likelihood to initiate actions when their mothers were engaged in a like action. That imitation by the mother is a pervasive characteristic of such interactions is consistent with earlier suggestions of its role in the acquisition of social and emotional skills. The results suggest that infants also display patterns of matching in early social interactions.     

Analyzing sequential relations in observational data: A practical guide

Many observational systems in basic and applied research produce a record of sequences of events over time. Within such observational systems, important information may be found in the frequency of the transitions between events that does not emerge in the typical researcher's focus on absolute event frequency. Indeed, if many behaviors are controlled by closely adjacent preceding events, then substantial prediction and control can be obtained through knowledge and manipulation of causal event transitions. A method for analyzing and testing sequential dependencies between events is proposed as part of an integrated package of computer-based data entry, storage, and analysis procedures. The mathematical portion of these techniques is based on the statistic, kappa,which is applicable to determining whether particular transitions among events differ from chance and whether particular transitions differ significantly across groups of subjects. Low-cost hardware and software to implement the proposed procedures are described.This work has been supported by Grant 1 RO1 HD19245-01A1 from the National Institute of Child Health and Human Development to the two senior authors and by grants of equipment from Commodore Computers, Inc., Koala Corporation, and NEC Telephones, Inc.     

A sequential cognitive diagnosis model for polytomous responses

This paper proposes a general polytomous cognitive diagnosis model for a special type of graded responses, where item categories are attained in a sequential manner, and associated with some attributes explicitly. To relate categories to attributes, a category‐level Q‐matrix is used. When the attribute and category association is specified a priori, the proposed model has the flexibility to allow different cognitive processes (e.g., conjunctive, disjunctive) to be modelled at different categories within a single item. This model can be extended for items where categories cannot be explicitly linked to attributes, and for items with unordered categories. The feasibility of the proposed model is examined using simulated data. The proposed model is illustrated using the data from the Trends in International Mathematics and Science Study 2007 assessment.     

A Mixed Model to Disentangle Variance and Serial Autocorrelation in Affective Instability Using Ecological Momentary Assessment Data

Affective instability, the tendency to experience emotions that fluctuate frequently and intensively over time, is a core feature of several mental disorders including borderline personality disorder. Currently, affect is often measured with Ecological Momentary Assessment protocols, which yield the possibility to quantify the instability of affect over time. A number of linear mixed models are proposed to examine (diagnostic) group differences in affective instability. The models contribute to the existing literature by estimating simultaneously both the variance and serial dependency component of affective instability when observations are unequally spaced in time with the serial autocorrelation (or emotional inertia) declining as a function of the time interval between observations. In addition, the models can eliminate systematic trends, take between subject differences into account and test for (diagnostic) group differences in serial autocorrelation, short-term as well as long-term affective variability. The usefulness of the models is illustrated in a study on diagnostic group differences in affective instability in the domain of eating disorders. Limitations of the model are that they pertain to group (and not individual) differences and do not focus explicitly on circadian rhythms or cycles in affect.     

听觉任务下汉语母语者对不同类型时间句的加工

采用听觉刺激-口头问答任务考察汉语母语者对指示性时间句和顺序性时间句的加工。结果表明:(1)对指示性时间句,被试的加工不受听觉刺激的呈现位置影响,时间概念与空间知觉之间无法形成对应的自动化联结;(2)对顺序性时间句,汉语母语者对出现在前方的"较早"事件和出现在后方的"较晚"事件反应快,出现了隐喻一致性效应,即汉语母语者更倾向于用"前"表示过去,用"后"表示未来。整个研究表明,对于汉语母语者而言,"自我参照点"和"时间参照点"两大时间隐喻系统都具有心理现实性,二者之间的区别在于是否有运动经验参与,并由此造成汉语母语者在听觉任务中对指示性时间句和顺序性时间句加工的差异。     

观察不同形状和颜色时眼运动的顺序性

实验使用EVM3200型眼动仪测量被试在观察四种不同形状和四种不同颜色时眼运动轨迹的特点,来研究人眼运动的顺序性。结果表明：人眼在观察不同形状和颜色时,眼运动具有时间序列和空间序列的特性;形状和颜色一样具有诱目性序列特征;眼运动凝视点受到刺激所处空间位置的明显影响;首次凝视点是研究眼运动的重要变量。     

Cross-cultural differences in processes underlying sequential cognitive activity

Abstract: Similarities and differences in the processes underlying performance on the Stroop Color-Word Test (Card A, 100 color words/black ink; Card B, 100 color patches; Card C, 100 color words/incongruous ink color) were investigated with Japanese ( N = 96) and Americans ( N = 96) with stimulus items read: (a) vertically, top to bottom; and (b) horizontally, left to right. Total time as well as errors, namely, those involved with the underlying processes of identification and sequential organization, were significantly longer or more frequent on Card C than on Cards A and B for both nationalities and spatial arrangements. Further, greater frequency of serial organization errors in females than in males was obtained for the Japanese group, and the opposite for the American group. The implications and directions for future research are discussed.     

Dynamics of waiting in pigeons

Two experiments used response-initiated delay schedules to test the idea that when food reinforcement is available at regular intervals, the time an animal waits before its first operant response (waiting time) is proportional to the immediately preceding interfood interval (linear waiting; Wynne & Staddon, 1988). In Experiment 1 the interfood intervals varied from cycle to cycle according to one of four sinusoidal sequences with different amounts of added noise. Waiting times tracked the input cycle in a way which showed that they were affected by interfood intervals earlier than the immediately preceding one. In Experiment 2 different patterns of long and short interfood intervals were presented, and the results implied that waiting times are disproportionately influenced by the shortest of recent interfood intervals. A model based on this idea is shown to account for a wide range of results on the dynamics of timing behavior.     

Differential diagnosis of steroid-dependent nephrotic syndrome with psychosis: Practical and ethical issues

The present case illustrates practical and ethical issues that can be encountered by clinical psychologists providing consultation services in medical settings. The neuropsychological consultation service was asked to evaluate a 22-year-old male with psychosis, steroid-dependent nephrotic syndrome, and a family history of schizophrenia. MRI revealedmarked cortical atrophy. Clinical findings were consistent with (1) steroid inducedapparent atrophy, which has been shown to be reversible with withdrawal of steroids; (2) uremia secondary to steroid withdrawal; (3) cortical atrophy, found in some schizophrenics; or (4) an atypical, diffuse degenerative disorder. Clinical interview and psychological testing revealed significant thought disorder, prominent delusions, somatic hallucinations, and mood disturbance. Deterioration in social and academic functioning was also present. Except for impaired attention and concentration, neuropsychological evaluation showed no clear evidence of brain-based dysfunction. Further, neuropsychological results effectively ruled out a degenerative process and were not consistent with a steroid effects profile. A conclusive differential diagnosis of steroid induced psychosis versus severe psychopathology would require withdrawal from steroids and antipsychotics. In addition to the practical and ethical issues of withholding antipsychotics, steroid withdrawal would require either dialysis or renal transplant surgery. Decision making regarding dialysis dependency and the possibility of postsurgical psychosis secondary to true psychopathology were salient issues to both the patient and the treatment team.     

Dependency, temporal contiguity, and response-independent reinforcement

A comparison was made of the effects of variable-interval, variable-time, and tandem variable-interval fixed-time schedules on key-peck responding of pigeons. The variable-interval component of the tandem schedule retained the response-reinforcement dependency; the fixed-time component allowed the temporal proximity between responding and reinforcement to vary, constrained only by the duration of the fixed-time interval. Response rates were highest during the variable-interval and lowest during the variable-time schedule. Intermediate response rates occurred during the tandem schedule. The results of a yoked control condition showed that the effects of the tandem schedule were not due simply to changes in reinforcement distribution or frequency. The results suggest that substantial reductions in responding occur when reinforcement is response-dependent but not necessarily contiguous with the response required to produce reinforcement.