Graphical representation fosters discovery in the 2-4-6 task

In the 2-4-6 rule discovery task, reasoners seek to discover a rule that governs the arrangement of three numbers (or triple). The to-be-discovered rule is “ascending numbers”. Upon being given the triple 2-4-6 as an initial example, however, reasoners tend to formulate algebraically specific hypotheses. Traditionally, this task is conducted primarily from an internal representation of the triples and candidate hypotheses. More recently, substantial representational effects have been demonstrated wherein an external representation of the dimensions of the problem space facilitated successful rule discovery. In the two experiments reported here, an interactive graphical representation was created by concurrently plotting each triple produced by the participants. In Experiment 1, participants who performed the task with this external representation were more likely to discover the rule than were a group of control participants. Experiment 2 replicated the effect but also assessed participants' hypotheses for each triple generated. Results indicated that a graphical representation of the triples fostered the development of hypotheses that were less constrained by the implied algebraic specificity of the initial triple.     

Quality of Life in Patients with Recurrent Vasovagal or Unexplained Syncope: Influence of Sex, Syncope Type and Illness Representations

Health-related quality of life (QoL) is reduced in patients with recurrent vasovagal (VVS) or unexplained (US) syncope. Little is known regarding these patients’ QoL as pertains to their capacity to attain their life goals. Factors influencing QoL, such as sex, syncope type and illness representations have not been studied. Our objective is to examine the relationship between illness representations and QoL, as well as possible sex and syncope type differences. One hundred and four patients undergoing tilt-table testing (TTT) for recurrent syncope were interviewed one month before TTT, using questionnaires. Data were analysed using ANCOVAs, a-priori Helmert contrasts for illness representations, and regressions. Patients with US had a poor QoL compared to those with VVS [F(1, 91) = 10.46; p < 0.01], particularly in men (p < 0.01). Patients with higher perceived syncope severity showed an impoverished QoL relative to those with less severe perceptions [F(1, 91) = 5.47; p < 0.05]. A hierarchical regression revealed that illness representations mediate the impact of lifetime number of syncope on QoL. In conclusion, QoL is reduced in these patients, and is influenced by illness representations. Helping patients change their perceptions about their syncope may be an efficient way to promote QoL.     

The Zuni Life Skills Development Program: a school/community-based suicide prevention intervention

The Zuni Life Skills Development Program, an effective community-initiated and high-school-based suicide prevention intervention, is featured. Development and evaluation of this intervention are followed by note of the specific challenges associated with stabilizing the program. A more tribally diverse, culturally-informed model entitled the American Indian Life Skills Development Curriculum is then presented to illustrate a hybrid approach to the cultural tailoring of interventions. This curriculum is broad enough to address concerns across diverse American Indian tribal groups yet respectful of distinctive and heterogeneous cultural beliefs and practices. Finally, we reflect upon issues in community-based research that emerged during this collaboration.     

What 50 years of research tell us about pausing under ratio schedules of reinforcement

Textbooks in learning and behavior commonly describe performance on fixed-ratio schedules as “break and run,” indicating that after reinforcement subjects typically pause and then respond quickly to the next reinforcement. Performance on variable-ratio schedules, on the other hand, is described as steady and fast, with few long pauses. Beginning with Ferster and Skinner''s magnum opus, Schedules of Reinforcement (1957), the literature on pausing under ratio schedules has identified the influences on pausing of numerous important variables, in particular ratio size and reinforcement magnitude. As a result, some previously held assumptions have been called into question. For example, research has shown that the length of the pause is controlled not only by the preceding ratio, as Ferster and Skinner and others had assumed (and as implied by the phrase postreinforcement pause), but by the upcoming ratio as well. Similarly, despite the commonly held belief that ratio pausing is unique to the fixed-ratio schedule, there is evidence that pausing also occurs under variable-ratio schedules. If such widely held beliefs are incorrect, then what about other assumptions? This article selectively examines the literature on pausing under ratio schedules over the past 50 years and concludes that although there may indeed be some common patterns, there are also inconsistencies that await future resolution. Several accounts of pausing under ratio schedules are discussed along with the implications of the literature for human performances, most notably the behaviors termed procrastination.     

State of Multicultural Neuropsychological Assessment in Children: Current Research Issues

Scientific attention to cultural considerations in child neuropsychological assessment has not developed parallel to the focus these issues have received in adult and elderly neuropsychological assessment. There are limited data on the presence, magnitude, etiology, and implications of culture-related differences in cognitive test performance among children. This preliminary report reviews the available empirical literature on the current state of multicultural neuropsychological assessment in children. The review identified articles by searching PubMed and PsycINFO databases, and the tables of contents of Developmental Neuropsychology and Child Neuropsychology from 2003-2008. Of the 1,834 abstracts reviewed, ten papers met inclusion criteria for the review. Five studies were completed in America; four of these compared performance between ethnic groups while the fifth examined neighborhood level poverty indicators exclusively within African-American children. Of the five international studies, all established local normative data and/or were exploratory investigations of neuropsychological functions in specific cultural groups, including Taiwanese infants, South African youth, and bilingual British children. Taken together, the results yield important clinical and research data that begin to inform many of the complex and fascinating mechanisms by which ethnic identity and culture impact cognitive development and the neuropsychological assessment of children. A critique of the existing literature and directions for future research are provided.     

Prediction of university students' academic achievement by linear and logistic models

University students' academic achievement measured by means of academic progress is modeled through linear and logistic regression, employing prior achievement and demographic factors as predictors. The main aim of the present paper is to compare results yielded by both statistical procedures, in order to identify the most suitable approach in terms of goodness of fit and predictive power. Grades awarded in basic scientific courses and demographic variables were entered into the models at the first step. Two hypotheses are proposed: (a) Grades in basic courses as well as demographic factors are directly related to academic progress, and (b) Logistic regression is more appropriate than linear regression due to its higher predictive power. Results partially confirm the first prediction, as grades are positively related to progress. However, not all demographic factors considered proved to be good predictors. With regard to the second hypothesis, logistic regression was shown to be a better approach than linear regression, yielding more stable estimates with regard to the presence of ill-fitting patterns.     

Belief, motivational, and ideological correlates of human rights attitudes

Many people believe that an informed and thoughtful citizenry is essential to the maintenance of democratic ideals within the United States and the spread of those ideals abroad. Since the September 11, 2001, terrorist attacks, the evidence that Americans consider issues of human dignity and rights when making judgments about the U.S. government's war on terror has been mixed. In our study, we assessed the relative contributions of ideological, belief, and cognitive-motivational factors to the prediction of human rights and civil liberties attitudes. Individuals scoring high on measures of right-wing authoritarianism (RWA) and the belief that the structure of knowledge is simple were the most likely to support restrictions on human rights and civil liberties as part of the war on terror. In a subsequent regression analysis, individuals scoring higher on personal need for structure or exhibiting lower levels of epistemological belief complexity tended to score higher on RWA. Additionally, men were generally more likely to support restrictions on rights and liberties and to score higher on RWA than were women.     

Avoidance of timeout from response-independent food: effects of delivery rate and quality

In three experiments, a rat's lever presses could postpone timeouts from food pellets delivered on response-independent schedules. In Experiment 1, the pellets were delivered at variable-time (VT) rates ranging from VT 0.5 to VT 8 min. Experiment 2 replicated the VT 1 min and VT 8 min conditions of Experiment 1 with new subjects. Finally, subjects in Experiment 3 could postpone timeouts from delivery of pellets that differed in quality rather than quantity (unsweetened versus sweetened pellets). In general, response rates and success in avoiding increased as a function of the rate and quality of the pellets. Also, performance efficiency increased as the experiments progressed, that is, the avoidance response occurred later and later in the response-timeout interval. The results support the conclusion that timeout from reinforcement has functional properties similar to those of more commonly studied aversive stimuli (e.g., shock).     

Influence of articulation rate on two memory tasks in young and older adults

This study investigated the relation between phonological loop functioning and age. Phonological loop is a time-based subsystem of the Working Memory Model of Baddeley and Wilson, which uses rehearsal of information as an active process to avoid phonological decay. Performance differences were examined between young and older adults in two speech-based memory tasks, such as the immediate serial recall of words and the Digit Ordering Task. Analysis showed that performance on both tasks was lower for the older group. Articulation rate was also measured to test the hypothesis that the impairment of some cognitive functions in adults can be associated to their slowness or the greater time needed by older adults for the rehearsal process. A significant negative correlation was found for articulation rate with age. When the effect of articulation rate on Serial Recall and Digit Ordering Tasks was partialled out, the difference between the two groups was eliminated.