Qualitative influences on the perception of movement: An experimental study

One of the most puzzling features of “hyperactivity” in children is the importance of activity itself. Generalized overactivity has not been found to be a valid diagnostic marker. Could some qualitative features of activity be important determinants of the perceived quantity of activity? The analogue study reported here derives from a social-psychological hypothesis that anything that makes a behavior more noticeable or distracting can create an illusion of increased movement. Subjects performed a simple cognitive task while watching short films of adult actors. Two variables were manipulated: (a) The sound level was either loud or quiet, and (b) instructions to subjects were varied so that the behaviors shown were perceived as either appropriate or inappropriate. Results strongly supported the hypothesis. Loudness and contextual inappropriateness made the films more distracting, produced higher ratings of the amount of movement observed, and led to more negative evaluations of the behaviors seen. Implications for assessment and intervention are discussed.     

Delayed temporal discrimination in pigeons: A comparison of two procedures

A within-subjects comparison was made of pigeons' performance on two temporal discrimination procedures that were signaled by differently colored keylight samples. During stimulus trials, a peck on the key displaying a slanted line was reinforced following short keylight samples, and a peck on the key displaying a horizontal line was reinforced following long keylight samples, regardless of the location of the stimuli on those two choice keys. During position trials, a peck on the left key was reinforced following short keylight samples and a peck on the right key was reinforced following long keylight samples, regardless of which line stimulus appeared on the correct key. Thus, on stimulus trials, the correct choice key could not be discriminated prior to the presentation of the test stimuli, whereas on position trials, the correct choice key could be discriminated during the presentation of the sample stimulus. During Phase 1, with a 0-s delay between sample and choice stimuli, discrimination learning was faster on position trials than on stimulus trials for all 4 birds. During Phase 2, 0-, 0.5-, and 1.0-s delays produced differential loss of stimulus control under the two tasks for 2 birds. Response patterns during the delay intervals provided some evidence for differential mediation of the two delayed discriminations. These between-task differences suggest that the same processes may not mediate performance in each.     

PIGEONS ARE SENSITIVE TO THE SPATIAL ORGANIZATION OF COMPLEX VISUAL STIMULI

Abstract— Two experiments investigated the role of spatial organisation in the discrimination and generalization of complex visual stimuli by pigeons. In Experiment 1, after pigeons had been trained to discriminate line drawings of four objects, they were tested with novel pictures in which the same component parts of the objects were spatially rearranged. The spatially scrambled pictures led to a dramatic drop in recognition accuracy, hut responding remained above chance. In Experiment 2, pigeons reached a high level of discriminative performance when required to choose among four different spatial arrangements of the same object parts. These results confirm Cerella's (1980) conclusion that pigeons discriminate the component parts of complex visual stimuli, but. unless it is assumed that the scrambling deleted or created emergent features, the results disconfirm his conclusion that spatial organization plays no role in pigeons' picture perception.     

Social networks with two sets of actors

Traditional network research analyzes relational ties within a single group of actors: the models presented in this paper involve relational ties exist beteen two distinct sets of actors. Statistical models for traditional networks in which relations are measured within a group simplify when modeling unidirectional relations measured between groups. The traditional paradigm results in a one-mode socionatrix; the network paradigm considered in this paper results in a two-mode socionatrix; A statistical model is presented, illustrated on a sample data set, and compared to its traditional counterpart. Extensions are discussed, including those that model multivariate relations simultaneously, and those that allow for the inclustion of attributes of the individuals in the group.We thank the Editor and two anonymous reviewers for their helpful comments. We are also grateful to George Barnett for allowing us to analyze his data.     

Conversational time patterns and mutual influence in parent-child interactions: A time series approach

Mutual influencing processes are assumed to be the basic building blocks in establishing parentchild bonding and in influencing cognitive and language behavior. A study by Jasnow and Feldstein (1986) revealed that, within the temporal domain of speech, preverbal (9-month-old) infants and their mothers exhibit a pattern of mutual influence (attunement) in their average durations of switching pauses. The general purpose of this research was to extend those findings to children with higher verbal functioning. In addition, parent and child genders, nature of the interaction, and specific aspects of parents' personalities, expressiveness, and instrumentality were considered. Each parent interacted with their 4-or 5-year-old son or daughter in each of two conversations—unstructured (social conversation) and structured (task activity). Conversations were processed by an automated computer system yielding objective measure of turns, vocalizations, pauses, and switching-pause durations. To examine interspeaker influence or attunement of temporal speech patterns, influence coefficients were computer for each speaker on a turn-by-turn basis using time series regression. Analysis of these coefficients revealed that: (1) Mutual influence is most evident with switching-pause duration. (2) Structure in the conversation (as defined by the task or parental instrumentality) seems to facilitate attunement for vocalization and switching pause duration. (3) Attunement with girls seems to occur equally well with both parents, while boys exhibit a style of temporal patterning influence which suggests greater identification with the father. (4) Expressiveness seems to facilitate attunement to the child's switching-pause duration.     

Perfectionism and Suicide Ideation in Adolescent Psychiatric Patients

This study was conducted to examine the relations between dimensions of perfectionism and suicide ideation in an adolescent psychiatric sample. A sample of 66 adolescents from an inpatient psychiatric facility completed the Child and Adolescent Perfectionism Scale, the Child's Hopelessness Scale, and the Suicide Ideation Questionnaire. Overall, the results indicated that socially prescribed perfectionism was associated with greater suicide ideation and that it, along with hopelessness, accounted for unique variance in suicide ideation scores. The findings are discussed in terms of their practical and theoretical significance as well as their consistency with similar research with adults.     

Learning spatial sequences in unilateral neglect

Brain-damaged patients with unilateral spatial neglect ignore aspects of the world located on the side opposite their lesion. In the present study we examined the performance of unilateral neglect patients (UN) on an SRT task in which a hybrid repeating sequence (21313) was used. We analyzed the patients' performance for each location separately as a function of the target's location in the trial preceding the response. The UN patients were severely limited in their learning of the sequence when compared to normal controls. In particular, they appeared to learn unique associations (21 and 13) but not ambiguous ones (31 and 32). We discuss two possible explanations for this phenomenon. The first is that UN patients show a deficit similar to that of normal subjects in dual task situations. The second is that the learning deficit is unique to spatial processing impairments of UN patients and is not directly related to research with normal population. We outline future research that may distinguish between these two explanations.