Chimpanzees (Pan troglodytes) recognize spatial and object correspondences between a scale model and its referent

In the present study, the contributions of spatial and object features to chimpanzees' comprehension of scale models were examined. Seven chimpanzees that previously demonstrated the ability to use a scale model as an information source for the location of a hidden item were tested under conditions manipulating the feature correspondence and spatial-relational correspondence between objects in the model and an outdoor enclosure. In Experiment 1, subjects solved the task under two conditions in which one object cue (color or shape) was unavailable, but positional cues remained. Additionally, performance was above chance under a third condition in which both types of object cues, but not position cues, were available. In Experiment 2, 2 subjects solved the task under a condition in which shape and color object cues were simultaneously unavailable. The results suggest that, much like young children, chimpanzees are sensitive to both object and spatial-relational correspondences between a model and its referent.     

Hierarchical categorization by bilingual Latino children: does a basic-level bias exist?

Research has shown that children classify most easily at the basic level where objects in the same category look similar enough to each other to be grouped together but are distinct enough from objects in other categories to be discriminated (e.g., animal/bird/duck). In this article, the authors report on 2 experiments they conducted to determine whether children maintain this basic category bias when the perceptual similarity of stimuli at different hierarchical levels is equalized. Pictures within and across 3 hierarchical levels were made perceptually equivalent and shown to 71 Latino children who were bilingual in Spanish and English. In Experiment 1, the pictures used as exemplars could be categorized on any of the 3 hierarchical levels. In Experiment 2, example pictures unambiguously defined the level of categorization that would be accurate, and linguistic cues were given that might assist in the selection of the correct category. In both experiments, the children sorted pictures from all 3 levels equally well, but they found it harder to justify their sorting of superordinate pictures. English competence predicted sorting on the more ambiguous sorting task in Experiment 1; and English competence predicted verbal justifications in both experiments, even though the experiments were conducted in Spanish. Competence in Spanish or English was an equally good predictor of sorting in the better defined sorting task in Experiment 2. These findings indicate that a superordinate level deficiency remains after perceptual differences are eliminated and that the deficiency is cognitive in nature. Differences in the performances of children who differed in bilingualism support the hypothesis that a threshold of proficiency in both languages is an important determinant of the effect of bilingualism on categorization.     

Effects of noncontingent reinforcement on problem behavior and stimulus engagement: the role of satiation, extinction, and alternative reinforcement

This study examined the effects of noncontingent reinforcement (NCR) with and without extinction on problem behavior and stimulus engagement (consumption of reinforcement) of 4 participants. Reductions in problem behavior using NCR have frequently been attributed to both satiation of the reinforcer and extinction. In the current study, aspects of the NCR treatment effects were difficult to explain based solely on either a satiation or an extinction account. Specifically, it was found that stimulus engagement remained high throughout the NCR treatment analysis, and that problem behavior was reduced to near-zero levels during NCR without extinction. The implications of these findings are discussed with respect to the satiation and extinction hypotheses frequently described in the applied literature. Findings from basic studies examining the effects of response-independent schedules are presented, and are used as the basis for a matching theory account of NCR-related effects. It is proposed that reductions in problem behavior observed during NCR interventions may be a function of the availability of alternative sources of reinforcement.     

Sex offenders, sentencing laws and pharmaceutical treatment: a prescription for failure

The phenomenon of adults who have sexual interests involving children as partners, or pedophiles, is considered among the most sociopathological of human conditions. Considerable literature is devoted to issues and problems associated with or related to pedophilia, including prevalence, etiology, treatment, and outcome studies. The sexual victimization of children, based upon data gathered from a number of sources, suggests an intractable problem that is national in scope. Recent manifestations of society's efforts to deal with the sexual victimization of children include the enactment of criminal sentencing laws that mandate the treatment of offenders with certain pharmaceutical agents, such as medroxy-progesterone acetate ("MPA"). Because sentencing laws as a rule vary widely from state to state, there is considerable variation as to who is subject to MPA treatment laws, and how such laws-including specific provisions, such as clinical criteria, if any, required for treatment; type and period of treatment plans; informed consent; etc-are implemented. Most important, these sentencing laws may have remarkably little relation to what is widely considered effective treatment for pedophilia disorders. We examine in detail the most recent sentencing laws pertaining to treatment of persons who have been convicted of sex offenses involving children as victims. Our critique may offer insight and suggestions as to how such sentencing laws can be more suitably tailored to the treatment needs of persons with pedophilia disorders.     

Training to Improve Calibration and Discrimination: The Effects of Performance and Environmental Feedback

This study investigated whether calibration and discrimination are distinct or related aspects of probability judgment accuracy by examining the effects of two different training techniques. Participants received either performance feedback or environmental feedback, and we measured their improvement in calibration and discrimination as a function of feedback type. Whereas performance feedback reduced participants' overconfidence and environmental feedback improved discrimination, neither type of feedback led to an improvement on the other component. In fact, environmental feedback led to an increase in overconfidence. We take these results as evidence that calibration and discrimination are dissociable abilities that require separate training techniques for improvement.     

The effects of reinforcement magnitude on functional analysis outcomes

The duration or magnitude of reinforcement has varied and often appears to have been selected arbitrarily in functional analysis research. Few studies have evaluated the effects of reinforcement magnitude on problem behavior, even though basic findings indicate that this parameter may affect response rates during functional analyses. In the current study, 6 children with autism or developmental disabilities who engaged in severe problem behavior were exposed to three separate functional analyses, each of which varied in reinforcement magnitude. Results of these functional analyses were compared to determine if a particular reinforcement magnitude was associated with the most conclusive outcomes. In most cases, the same conclusion about the functions of problem behavior was drawn regardless of the reinforcement magnitude.     

Childhood amnesia in children and adolescents: their earliest memories

Investigations of childhood amnesia have almost exclusively focused on the earliest memories of adults. Here we investigate the earliest memories of children of 6--19 years old. Parents confirmed the memory events and dated the memories. There were surprisingly few developmental differences between the earliest memories of children. Although 6--9-year-olds recalled earlier events than did older children, there were no differences between older age groups. Memories from all age groups were similar in structure, social orientation, and the nature of the recalled event. However, memories of older children were more likely to involve negative affect. There were also few gender differences, although girls were more likely to recall traumatic or transitional events while boys were more likely to recall play events. Overall, results deepen the paradox of early memory: 6--9-year-olds have verbally accessible memories from very early childhood that then seem to disappear as they get older.     

Strength of visual percept generated by famous faces perceived without awareness: effects of affective valence, response latency, and visual field

Participants who were unable to detect familiarity from masked 17 ms faces (Stone and Valentine, 2004 and Stone and Valentine, in press-b) did report a vague, partial visual percept. Two experiments investigated the relative strength of the visual percept generated by famous and unfamiliar faces, using masked 17 ms exposure. Each trial presented simultaneously a famous and an unfamiliar face, one face in LVF and the other in RVF. In one task, participants responded according to which of the faces generated the stronger visual percept, and in the other task, they attempted an explicit familiarity decision. The relative strength of the visual percept of the famous face compared to the unfamiliar face was moderated by response latency and participants' attitude towards the famous person. There was also an interaction of visual field with response latency, suggesting that the right hemisphere can generate a visual percept differentiating famous from unfamiliar faces more rapidly than the left hemisphere. Participants were at chance in the explicit familiarity decision, confirming the absence of awareness of facial familiarity.     

Bilingualism and adult differences in inhibitory mechanisms: evidence from a bilingual stroop task

The present investigation examined the functioning of inhibitory mechanisms in younger and older bilinguals using a bilingual version of the Stroop test. The study predicted different patterns of age related decline in inhibitory mechanisms (inter- and intralingual interference) in bilinguals depending on their level of proficiency. Consistent with expectations, older bilinguals were slower when they responded in their non-dominant language. Furthermore, older unbalanced bilinguals showed greater interlingual interference when they responded with their second language to visual stimuli written in their dominant language. Balanced bilinguals showed equivalent interference effects between all conditions. These findings suggest that manipulating two languages may enhance the efficiency of inhibitory mechanisms.     

Clever hands: uncontrolled intelligence in facilitated communication

Five studies examined how people who are answering questions on behalf of another person may use their own knowledge to answer correctly while attributing authorship of their answers to the other. Experiments 1 and 2 found that participants instructed to answer yes/no questions randomly were unable to do so. They were more often correct on easy than hard questions, and extended opportunity and incentive did not reduce this effect. Experiments 3-5 found similar correctness for participants who were asked to answer yes/no questions by sensing either the ostensible keyboard finger movements or unvoiced inclinations of another person who had been admonished not to answer, and who was infact a confederate and was not even given the questions. In this paradigm, the answers were often attributed to the other.