Discrimination of circles and squares with and without knobs by goldfish

Different groups of goldfish were trained to discriminate between a circle and either a square, a diamond, a square with a knob added at the top or a diamond with a knob. All subjects readily mastered the discrimination, and there was no significant difference between the groups in the number of trials taken to criterion. In transfer tests it was found that: (i) while there was no transfer from square to diamond or vice versa, the presence of knobs on these shapes did mediate transfer from one to the other, provided the knob remained in the top part of the shapes; (ii) all groups learned much more about the tops of the shapes than about the bottom halves; (iii) animals discriminated the square from the circle largely by detecting the presence of a strong horizontal edge at the top of the figure; (iv) two features of the diamond were discriminated--the presence of oblique contours and the existence of a point in the upper half of the shape. The results are discussed in terms of a proposed model of shape recognition.     

DIRECT AND COLLATERAL EFFECTS OF RESTRAINTS AND RESTRAINT FADING

Mechanical restraints are commonly used to reduce the risks associated with severe self-injurious behavior (SIB), but may result in movement restriction and adverse side effects (e.g., bone demineralization). Restraint fading may provide a method for decreasing SIB while increasing movement and reducing these side effects. In the current investigation, rigid arm sleeves and restraint fading (gradually reducing the rigidity of the sleeves) were used with 3 clients who engaged in hand-to-head SIB. Restraints and fading reduced the hand-to-head SIB of all clients. However, for 1 client, the addition of a water mist procedure further reduced SIB to near-zero levels. For a 2nd client, another form of SIB developed that was not prevented by the rigid sleeves. For a 3rd client, a topography of SIB that was not physically prevented by the rigid sleeves was also reduced when restraints and fading were introduced.     

The noble savage and the global village: Cultural evolution in new age and neo‐pagan THOUGHT

This article examines some of the assumptions underlying cultural evolution and such concepts as the Noble Savage and the Golden Age. Looking briefly at the influence and inference of these ideas in the past, their use and appearance in certain aspects of contemporary Pagan and New Age thought are then explored. The notion of the Noble Savage has recurred in various guises since at least classical times, and people have looked longingly to a lost Golden Age in history, myth or religion throughout recorded history. The theory of cultural evolution has had ramifications for both concepts, while in some respects seeming inimical to them. Now aspects of these three ideas are having spiritual implications for a large number of people. Examining the connections between them and contemporary religiosity can therefore provide useful insights towards our understanding of the present phenomena.     

Relating print and speech: the effects of letter names and word position on reading and spelling performance

From an early age, children can go beyond rote memorization to form links between print and speech that are based on letter names in the initial positions of words (Treiman & Rodriguez, 1999; Treiman, Sotak, & Bowman, 2001). For example, children's knowledge of the name of the letter t helps them learn that the novel word TM is pronounced as team. Four experiments were carried out to determine whether letter names at the ends of words are equally useful. Four- and five-year-olds derived little benefit from such information in reading (Experiments 1 and 3) or spelling (Experiment 2), although adults did (Experiment 4). For young children, word-final information appears to have less influence on reading and spelling performance than does word-initial information. The results help delineate the circumstances under which children can go beyond a logographic approach in learning about print.     

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 differences in the effect of articulatory or spatial dual-task interference during navigation

Women are more likely to employ landmark-based strategies when navigating, and they are superior at employing this type of strategy. The cause of this sexually dimorphic behaviour is unknown. Seventy-nine undergraduates performed a matrix navigation task wherein the symbols within the matrix were highly nameable. Participants were either given landmark-based or Euclidean-based instructions for navigation within the matrix. During navigation, participants were subjected to either articulatory or spatial interference. The articulatory interference selectively impaired women's ability to navigate correctly, regardless of the type of instruction. The performance of the men was not affected differentially by the two types of interference. When given a test of symbol recognition following the navigation task, women recognized more of the symbols employed in the task. Collectively, this result suggests that women rely on linguistic information more than men do when navigating, regardless of the type of instruction.     

Chronically stressed female rats show increased anxiety but no behavioral alterations in object recognition or placement memory: a preliminary examination

Stress, depending on intensity and duration, elicits adaptive or maladaptive physiological effects. Increasing evidence shows those patterns of advantageous versus deleterious physiologic stress effects also exist for some brain functions, including learning and memory. For example, short stress enhances, while chronic stress impairs, performance on numerous cognitive tasks in male rats. In contrast, performance of female rats is enhanced, or not altered, following both short-term and long-term stress exposure on the same behavioral tasks. The current study was designed to better characterize the behavioral effects of sustained chronic restraint stress in female rats. Female Sprague Dawley rats were assigned to a stress (restraint, 6 h/day, 35 days) or control (no stress) condition, weighed weekly, and then tested on open field (OF), object recognition (OR) and object placement (OP) tasks. Stressed females gained less weight during stress than controls. On the OF, there were no group differences in locomotor activity, but stressed females made fewer inner visits than controls, indicating increased anxiety. Both groups successfully performed the OP and OR tasks across all inter-trial delays, indicating intact non-spatial and spatial memory in both control and stress females. The current results provide preliminary evidence that the commonly used chronic restraint stress model may not be an efficient stressor to female rats.