The integration of knowledge and experimentation strategies in understanding a physical system

This study investigated how people integrate different kinds of knowledge in coming to understand the functions of components of a physical system. Twenty-three undergraduates worked on a hypothesis-testing task in which they constructed test circuits to decide the identity of electrical components hidden inside boxes. The students' problem-solving was driven by qualitative causal models that included ideas about cause and effect, task demands, and functions of circuits and circuit components. There was a hierarchy of four causal models, with higher levels representing increasing understanding and supporting increasingly successful problem solution. These causal models were associated with characteristic experimentation strategies, including strategies for generating evidence, interpreting evidence, and managing memory requirements. Some of these strategies followed directly from the causal model a student held, whereas others appeared to be more general. The level of understanding a student eventually attained about this physical system was a function of both domain knowledge and proficiency in experimentation strategies.     

Nine-month-old infants learn about a physical event in a single session: Implications for infants' understanding of physical phenomena

Infants' ability to learn about physical phenomena after only brief training was observed. During training, infants first observed and handled a weighted ball or an identical-looking empty ball, then watched an experimenter place a ball in the bottom of a tube connected to a paddle. When infants pressed the paddle, the empty ball ascended the tube while the weighted ball stayed down. During test trials infants experienced trials that were consistent and inconsistent (i.e., heavy ball ascended and empty ball did not) with training trials. Infants pressed and looked longer at the inconsistent events. A second experiment replicated the findings and ensured that infants were not using prior knowledge about gravity and weight. Infants formed a representation of what was inside the balls, remembered what each ball did during training, and detected a violation of expectations about the ball's movement.     

Knowledge in transition: Adults' developing understanding of a principle of physical causality

What are the conditions that make it likely that cognitive change will occur? We investigate this issue with respect to 25 college students' developing understanding of gear movement (a particular problem in the domain of physical causation). The participants solved problems, then received minimal instruction, and solved additional problems. Significantly, only some of the participants changed their approach to solving the problems after receiving instruction; the remainder of the participants were stable in their understanding and either continued to solve all problems correctly or continued to solve key problems incorrectly. Most analyses focused on the participants who began by solving problems incorrectly. In particular, we attempted to differentiate those participants who exhibited cognitive change from those who did not. To do this, we examined precursors of knowledge change that were motivated by different theoretical positions on mechanisms of cognitive change and development (i.e., consideration of multiple approaches, cognitive conflict, and instruction as an example of a sociocultural process). Results suggest that having multiple approaches available and using instructional information to build on not-well-developed conceptions are likely candidates for understanding knowledge change for adult participants with respect to their developing understanding of physical causality.     

Grey parrot numerical competence: a review

The extent to which humans and nonhumans share numerical competency is a matter of debate. Some researchers argue that nonhumans, lacking human language, possess only a simple understanding of small quantities, generally less than four. Animals that have, however, received some training in human communication systems might demonstrate abilities intermediate between those of untrained nonhumans and humans. Here I review data for a Grey parrot (Psittacus erithacus) that has been shown to quantify sets of up to and including six items (including heterogeneous subsets) using vocal English labels, to comprehend these labels fully, and to have a zero-like concept. Recent research demonstrates that he can also sum small quantities. His success shows that he understands number symbols as abstract representations of real-world collections, and that his sense of number compares favorably to that of chimpanzees and young human children.     

Discontinuities in early development of the understanding of physical causality

Research on early physical reasoning has shown surprising discontinuities in developmental trajectories. Infants possess some skills that seem to disappear and then re-emerge in childhood. It has been suggested that prediction skills required in search tasks might cause these discontinuities (Keen, 2003). We tested 3.5- to 5-year-olds’ understanding of collision events using a forced-choice paradigm with reduced prediction demands. Although the group as a whole performed at chance level, when the preschoolers were subdivided into three age groups, the oldest group performed above chance level. These findings suggest that it is unlikely to be prediction skills that affect young preschoolers’ performance on physical reasoning tasks. The findings lend support to a task-demand hypothesis, which proposes that discontinuities in developmental trajectories can be explained by differences in the extent to which cognitive processes are required by the different tasks.     

Children's understanding of physical illnesses and psychological states

Abstract

The present study set out to compare 5.7, and 9-year-old children's understanding of a physical illness (chicken pox) with their understanding of a psychological state (depression). In addition, information about personal experience of the illnesses and external sources of information was elicited, in order to assess the effects of both age and experience. Children at all ages showed a basic intact knowledge of both chicken pox and depression, although older children had a more sophisticated understanding of depression, and had acquired this knowledge from a greater number of sources. The clinical implications of the findings, and their relationship to both neo-Piagetian and more recent theories of conceptual development in childhood are discussed.     

Stimulation-induced behavioral inhibition: a new model for understanding physical violence.

Physical violence is widely considered to result from action carried out with the intention of causing injury; that is, from aggression. However, the "hypothesis" of aggression is inapplicable in all but a few instances as well as inappropriate for many destructive, rage-associated responses directed at inanimate objects. This paper outlines a new perspective on physical violence, reinterpreting many behaviors hitherto labeled aggressive as stimulation-seeking behaviors (SSBs) above an arbitrary level of intensity. It is further proposed that: 1) physical violence is a by-product of SSB, driven in part by brain catecholaminergic (CA) systems, and the direct result of exchanges of energy that exceed the body's tolerance threshold; 2) allegedly discrete categories of motor-motivational behavior represent overlapping bands of intensity on a continuous spectrum of SSB; and 3) the sensory input derived from SSB is fed back into the central nervous system where it activates brain serotonergic and/or cholinergic systems, which in turn inhibit CA systems, resulting in a general state of behavioral quiescence. In addition to accounting for a number of previously unexplained observations, the model suggests that physical violence could be prevented by providing groups at high risk with extensive opportunities for therapeutic sensory stimulation to substitute for that derived from excessive SSB. For people at especially high risk, portable devices could be developed that would allow the user to self-administer desired levels of sensory stimulation at moments of intense anger, thereby preventing potentially dangerous outbursts of SSB prior to the onset of the behavior.     

Simultaneous development of vocal and physical object combinations by a Grey parrot (Psittacus erithacus): bottle caps, lids, and labels

On the basis of primarily behavioral data, researchers (e.g., P. M. Greenfield, 1991) have argued (a) that parallel development of communicative and physical object (manual) combinatorial abilities exists in young children; (b) that these abilities initially have a common neural substrate; (c) that a homologous substrate in great apes allows for similar, if limited, parallel development of these 2 abilities; and (d) that such abilities thus may indicate a shared evolutionary history for both communicative and physical behavior (J. Johnson-Pynn, D. M. Fragaszy, E. M. Hirsh, K. E. Brakke, & P. M. Greenfield, 1999). The authors of the present study found a comparable, if limited, parallel combinatorial development in a Grey parrot (Psittacus erithacus). Given the evolutionary distance between parrots and primates, the authors suggest that the search for and arguments concerning responsible substrates and common behavior should be approached with care and should not be restricted to the primate line.     

Stacking of blocks by chimpanzees: developmental processes and physical understanding

The stacking-block task has been used to assess cognitive development in both humans and chimpanzees. The present study reports three aspects of stacking behavior in chimpanzees: spontaneous development, acquisition process following training, and physical understanding assessed through a cylindrical-block task. Over 3 years of longitudinal observation of block manipulation, one of three infant chimpanzees spontaneously started to stack up cubic blocks at the age of 2 years and 7 months. The other two infants began stacking up blocks at 3 years and 1 month, although only after the introduction of training by a human tester who rewarded stacking behavior. Cylindrical blocks were then introduced to assess physical understanding in object-object combinations in three infant (aged 3-4) and three adult chimpanzees. The flat surfaces of cylinders are suitable for stacking, while the rounded surface is not. Block manipulation was described using sequential codes and analyzed focusing on failure, cause, and solution in the task. Three of the six subjects (one infant and two adults) stacked up cylindrical blocks efficiently: frequently changing the cylinders' orientation without contacting the round side to other blocks. Rich experience in stacking cubes may facilitate subjects' stacking of novel, cylindrical shapes from the beginning. The other three subjects were less efficient in stacking cylinders and used variable strategies to achieve the goal. Nevertheless, they began to learn the effective way of stacking over the course of testing, after about 15 sessions (75 trials).     

Ordinality and inferential abilities of a grey parrot (Psittacus erithacus)

A grey parrot (Psittacus erithacus), able to label the color of the bigger or smaller object in a pair (I. M. Pepperberg & M. V. Brezinsky, 1991), to vocally quantify < or =6 item sets (including heterogeneous subsets; I. M. Pepperberg, 1994), and separately trained to identify Arabic numerals 1-6 with the same vocal English labels but not to associate Arabic numbers with their relevant physical quantities, was shown pairs of Arabic numbers or an Arabic numeral and a set of objects and was asked for the color of the bigger or smaller one. The parrot's success showed he (a) understood number symbols as abstract representations of real-world collections, (b) inferred the relationship between the Arabic number and the quantity via stimulus equivalence, and (c) understood the ordinal relationship of his numbers.     

Stimulation-induced behavioral inhibition: A new model for understanding physical violence

Physical violence is widely considered to result from action carried out with the intention of causing injury; that is, from aggression. However, the “hypothesis” of aggression is inapplicable in all but a few instances as well as inappropriate for many destructive rage-associated responses directed at inanimate objects. This paper outlines a new perspective on physical violence, reinterpreting many behaviors hitherto labeled aggressive as stimulation-seeking behaviors (SSBs) above an arbitrary level of intensity. It is further proposed that: 1) physical violence is a by-product of SSB, driven, in part by brain catecholaminergic (CA) systems, and the direct result of exchanges of energy that exceed the body's tolerance threshold; 2) allegedly discrete categories of motor-motivational behavior represent overlapping bands of intensity on a continuous spectrum of SSB; and 3) the sensory input derived from SSB is fed back into the central nervous system where it activates, brain serotonergic and/or cholinergic systems, which in turn inhibit CA systems, resulting in a general state of behavioral quiescence. In addition to accounting for a number of previously unexplained observations, the model suggests that physical violence could be prevented by providing groups at high risk with extensive opportunities for therapeutic sensory stimulation to substitute for that derived from excessive SSB. For people at especially high risk, portable devices could be developed that would allow the user to self-administer desired levels of sensory stimulation at moments of intense anger, thereby preventing potentially dangerous outbursts of SSB prior to the onset of the behavior.     

Limited spread of innovation in a wild parrot, the kea (Nestor notabilis)

In the local population of kea in Mount Cook Village, New Zealand, some keas open the lids of rubbish bins with their bill to obtain food scraps within. We investigated the extent to which this innovation has spread in the local population, and what factors limit the acquisition of bin opening. Only five males of 36 individually recognised birds were observed to have performed successful bin opening. With one exception there were always other keas present, watching successful bin opening. Seventeen additional individuals were seen to have benefitted from lid opening. Their foraging success was less than that of the bin openers. Social status of bin openers did not differ from scrounging males. Among the individuals that were regularly seen at the site of the bins but were not successful in bin opening, social status and the ratio of feeding directly from open bins correlated with the amount of opening attempts. We conclude that scrounging facilitated certain behavioural aspects of bin opening rather than inhibiting them. The fact that only 9% of opening attempts were successful, and the long period of time required to increase efficiency in lid opening shows that mainly individual experience, and to a lesser extent insight and social learning, play key roles in acquisition of the opening technique. The results indicate that the spread of innovative solutions of challenging mechanical problems in animals may be restricted to only a few individuals.     

Number comprehension by a grey parrot (Psittacus erithacus), including a zero-like concept

A Grey parrot (Psittacus erithacus) that was able to quantify 6 item sets (including subsets of heterogeneous groups, e.g., blue blocks within groupings of blue and green blocks and balls) using English labels (I. M. Pepperberg, 1994a) was tested on comprehension of these labels, which is crucial for numerical competence (K. C. Fuson, 1988; see also record 1987-98811-000). He was, without training, asked "What color/object [number]?" for collections of various simultaneously presented quantities (e.g., subsets of 4, 5, and 6 blocks of 3 different colors; subsets of 2, 4, and 6 keys, corks, and sticks). Accuracy was greater than 80% and was unaffected by array quantity, mass, or contour. His results demonstrated numerical comprehension competence comparable to that of chimpanzees and very young children. He also demonstrated knowledge of absence of quantity, using "none" to designate zero.     

Children's conceptions of physical events: Explicit and tacit understanding of horizontal motion

The conceptual understanding that children display when predicting physical events has been shown to be inferior to the understanding they display when recognizing whether events proceed naturally. This has often been attributed to differences between the explicit engagement with conceptual knowledge required for prediction and the tacit engagement that suffices for recognition, and contrasting theories have been formulated to characterize the differences. Focusing on a theory that emphasizes omission at the explicit level of conceptual elements that are tacitly understood, the paper reports two studies that attempt clarification. The studies are concerned with 6‐ to 10‐year‐old children's understanding of, respectively, the direction (141 children) and speed (132 children) of motion in a horizontal direction. Using computer‐presented billiards scenarios, the children predicted how balls would move (prediction task) and judged whether or not simulated motion was correct (recognition task). Results indicate that the conceptions underpinning prediction are sometimes interpretable as partial versions of the conceptions underpinning recognition, as the omission hypothesis would imply. However, there are also qualitative differences, which suggest partial dissociation between explicit and tacit understanding. It is suggested that a theoretical perspective that acknowledges this dissociation would provide the optimal framework for future research.     

Probing the limits of tool competence: Experiments with two non-tool-using species (Cercopithecus aethiops and Saguinus oedipus)

Non-human animals vary in their ability to make and use tools. The goal of the present study was to further explore what, if anything, differs between tool-users and non-tool-users, and whether these differences lie in the conceptual or motor domain. We tested two species that typically do not use tools-cotton top tamarins (Saguinus oedipus) and vervet monkeys (Cercopithecus aethiops)-on problems that mirrored those designed for prolific tool users such as chimpanzees. We trained subjects on a task in which they could choose one of two canes to obtain an out-of-reach food reward. After training, subjects received several variations on the original task, each designed to examine a specific conceptual aspect of the pulling problem previously studied in other tool-using species. Both species recognized that effective pulling tools must be made of rigid materials. Subsequent conditions revealed significant species differences, with vervets outperforming tamarins across many conditions. Vervets, but not tamarins, had some recognition of the relationship between a tool's orientation and the position of the food reward, the relationship between a tool's trajectory and the substance that it moves on, and that tools must be connected in order to work properly. These results provide further evidence that tool-use may derive from domain-general, rather than domain-specific cognitive capacities that evolved for tool use per se.     

Toward a further understanding of assent

Arranging assent opportunities is an increasingly common strategy for involving clients in therapeutic decisions within behavior analysis. Recent behavior-analytic articles have helped create a basic behavioral definition and conceptualization of assent, but much more guidance is needed for practitioners and researchers interested in embedding assent into their practices. The purpose of this article is to advance the conceptualization and understanding of assent and assent practices by refining previous definitions and conceptualizations of assent and providing six essential considerations for embedding assent into practice. The six considerations consist of determining the applicability and feasibility of assent, assessing assent-related skills, arranging assent procedures and teaching assent-related skills, arranging fair choices, selecting opportunities to assess assent, and informally assessing assent. Following the discussion of the considerations for assent practices, we issue a call for specific topics of research on assent.     

Further evidence for addition and numerical competence by a Grey parrot (Psittacus erithacus)

A Grey parrot (Psittacus erithacus), able to quantify sets of eight or fewer items (including heterogeneous subsets), to sum two sequentially presented sets of 0–6 items (up to 6), and to identify and serially order Arabic numerals (1–8), all by using English labels (Pepperberg in J Comp Psychol 108:36–44, 1994; J Comp Psychol 120:1–11, 2006a; J Comp Psychol 120:205–216, 2006b; Pepperberg and Carey submitted), was tested on addition of two Arabic numerals or three sequentially presented collections (e.g., of variously sized jelly beans or nuts). He was, without explicit training and in the absence of the previously viewed addends, asked, “How many total?” and required to answer with a vocal English number label. In a few trials on the Arabic numeral addition, he was also shown variously colored Arabic numerals while the addends were hidden and asked “What color number (is the) total?” Although his death precluded testing on all possible arrays, his accuracy was statistically significant and suggested addition abilities comparable with those of nonhuman primates.