HYPOTHESIS-BASED INTERVENTIONS FOR TANTRUM BEHAVIORS OF PERSONS WITH DEVELOPMENTAL DISABILITIES IN SCHOOL SETTINGS

We conducted a functional assessment of problem behaviors of 2 students with developmental disabilities in their classroom environments. Results of the assessments showed that although there were more tantrums in demand than in no-demand conditions, the function of the behavior was to gain attention (positive reinforcement) rather than to avoid or escape demands (negative reinforcement); demand conditions apparently served a discriminative function for the availability of attention. Therefore, intervention was based on the positive reinforcement hypothesis, resulting in a substantial reduction of tantrums for both subjects.     

I am not a Crook: Effects of Denials on Perceptions of a Defendant's Guilt, Personality, and Motives

Two studies were conducted to explore the effects of a defendant's overinformative denials (i.e., denials not prompted by an accusation or specific request) in a courtroom trial. Subjects read the testimony of a defendant who either did or did not deny several negative propositions (Study I) or whose denials either were or were not in response to the prosecutor's questions (Study 2). The denials had little effect on subjects' beliefs regarding the denied propositions. However, the defendant who provided the overinformative denials was perceived as being less trustworthy, more nervous, more concerned with presenting a positive image, and more likely to believe that others believed the negative propositions. Subjects who read the testimony of this defendant also generated more negative and fewer positive thoughts, and they perceived the defendant as being more guilty. The results illustrate the importance of the conversational context for determining the pragmatic meaning of a speaker's remarks.     

Towards a Hierarchical Model of Self-concept for Hong Kong Chinese Adults with Physical Disabilities

This paper explores the basic facets and structure of the self-concepts of groups of 135 and 146 Hong Kong Chinese adults with and without physical disabilities, respectively. Comparison of responses to a 20-item scale indicated a very similar pattern of the importance the individuals in these groups attached to these areas of their lives. However, the non-disabled group did report higher satisfaction ratings on six of these areas and factor analysis of both the importance and satisfaction ratings showed a similar underlying factor structure for both groups. Content analysis of open-ended questions confirmed that both groups shared similar self-concept facets except that the subjects with physical disabilities most frequently reported the importance of “functional independence in daily living tasks”. It is proposed that this facet needs to be included in a self-concept instrument appropriate for subjects with physical disabilities. Models of self-concept were then suggested for each group.     

Stimulus-independent thought depends on central executive resources

Stimulus-independent thoughts (SITs) are streams of thoughts and images unrelated to immediate sensory input. Four experiments examined the contribution of aspects of working memory to production of SITs. In Experiments 1 and 2, interventions that were targeted on, respectively, phonological and visuospatial components of working memory both interfered with production of SITs, but there was evidence that these tasks also made demands on central executive resources. Experiments 3 and 4 specifically examined the hypothesis that production of SITs and control of nonproceduralized tasks both depend on central executive resources, and so should show mutual interference. In Experiment 3, prior practice on pursuit rotor and memory tasks reduced the interference with SITs from concurrent task performance. In Experiment 4, randomness within a task involving random-number generation was less when SITs were being produced concurrently than it was when they were not. The results suggest that production of SITs depends on central executive resources.     

GUIDED VISUAL SEARCH IS A LEFT-HEMISPHERE PROCESS IN SPLIT-BRAIN PATIENTS

Abstract— Previous research has shown that split-brain (callosotomy) patients search through visual displays twice as fast as normal observers when items are divided evenly between visual hemifields, as though each disconnected hemisphere possessed its own attentional scanning system (Luck, Hillyard, Mangun, & Gazzaniga, 1989, 1994) Results from 3 split-brain patients in the present study indicate that the ability to limit search to a relevant subset of the visual display is lateralized to the left cerebral hemisphere. This ability to perform guided search was not shown in the right hemisphere, even when the search time in that hemisphere was superior to search time in the left Furthermore, guided search was observed for both hemifields in normal control observers. These findings suggest that, as with higher cognitive processes such as language, strategic visuospatial attentional processes are preferentially lateralized to the left cerebral hemisphere. The findings also imply that the callosum mediates guided search in the right hemisphere of normal subjects     

Case study: Examining the relationship between self-initiations of an individual with disabilities and directive behavior of staff persons in a residential setting

This case study examines the relationship between self-initiations of an adult woman with severe disabilities and the directive behavior of staff persons in a community residential setting. Hypotheses generated from functional assessment procedures indicated that (a) Susan's low self-initiations were very likely related to high directive behavior of staff persons, and (b) infrequent problem behaviors during the morning routine were maintained by escape from repeated staff demands. An intervention was implemented to enable Susan to increase self-initiation in choice and sequence of activities and simultaneously decrease staff directives. Results and discussion focus on the need for a contextual approach for addressing problematic situations and an affirmation of the effectiveness of the positive behavioral support technology for increasing adaptive behaviors in individuals with severe disabilities.     

Functional Aspects of Recollective Experience in Face Recognition

This article describes two experiments on awareness in recognition memory for novel faces. Two kinds of awareness, recollective experience and feelings of familiarity in the absence of recollective experience, were measured by "remember" and "know" responses. Experiment 1 showed that "remember" but not "know" responses were reduced by divided attention at study. Experiment 2 showed that massed versus spaced repetition of faces in the study list had the opposite effects on "remember" and "know" responses. Massed repetition increased "know" responses and reduced "remember" responses. Spaced repetition increased "remember" responses and reduced "know" responses. The results of both experiments replicate previous findings from the verbal domain in the domain of face recognition, and hence they increase the ecological validity of this experiential approach to memory and awareness and the generality of its database. These findings are discussed from a rehearsal perspective on factors influencing the two states of awareness and in relation to the alternative "process dissociation" procedure.     

Are microsaccades responsible for the gap effect?

Extinguishing a fixation point shortly before, or concurrently with, the onset of a peripheral visual target reduces the latency of saccades to that target. Saslow (1967) hypothesized that thisgap effect might occur because fixation point offsets reduce the incidence of corrective microsaccades with an associated saccadic refractory period. In the present study, a robust gap effect was obtained. However, using a Purkinje image eyetracker with 1 arcmin of resolution, we found that fixation point offsets had no effect on the occurrence of microsaccades and that the occurrence of microsaccades had no impact on the magnitude of the gap effect. Microsaccades therefore do not appear to play any part in the production of the gap effect.