Associative learning in baboons (Papio papio) and humans (Homo sapiens): species differences in learned attention to visual features

We examined attention shifting in baboons and humans during the learning of visual categories. Within a conditional matching-to-sample task, participants of the two species sequentially learned two two-feature categories which shared a common feature. Results showed that humans encoded both features of the initially learned category, but predominantly only the distinctive feature of the subsequently learned category. Although baboons initially encoded both features of the first category, they ultimately retained only the distinctive features of each category. Empirical data from the two species were analyzed with the 1996 ADIT connectionist model of Kruschke. ADIT fits the baboon data when the attentional shift rate is zero, and the human data when the attentional shift rate is not zero. These empirical and modeling results suggest species differences in learned attention to visual features. Received: 30 May 1998 / Accepted after revision: 13 September 1998     

Premorbid behavioral and psychosocial adjustment of children with traumatic brain injury

The premorbid adjustment of 85 six- to sixteen-year-old children with traumatic brain injury was assessed by means of standardized rating forms that were completed by the children's parents and teachers. Parents and teachers were in moderate agreement when rating children's premorbid functioning. Less than 11% of the children appeared to have premorbid disturbances. Premorbid adjustment did not appear to be clearly related to injury severity or to type of injury. It is concluded that premorbid behavioral and psychosocial factors are not strongly related to the incidence of traumatic brain injury in a sample of children with predominantly relatively severe injuries.The author gratefully acknowledges the assistance of Amy Herrema, Kevin Hogeterp, and Mary Jeanne Lynch in the data collection process.     

Rule selection versus rule execution in preschoolers: an error-detection approach.

In 2 experiments, an error-detection approach was used to determine whether 3-year-olds' perseverative errors on the postswitch phase of the Dimensional Change Card Sort (DCCS) are due to lack of response control or representational inflexibility. In Experiment 1, 3-, 4-, and 5-year-olds watched a puppet sort perseveratively on the postswitch phase and evaluated its responses. Most 4- and 5-year-olds detected the puppet's perseverative errors, whereas most 3-year-olds failed to do so despite detecting errors on a simpler card sort. Experiment 2 revealed that 3-year-olds who failed to correctly evaluate the puppet's behavior tended to fail their own DCCS. Results imply that perseveration on the DCCS cannot be attributed to difficulty inhibiting prepotent motor responses. Instead, changes in rule use between 3 and 5 years of age are interpreted in terms of the development of representational flexibility.     

Psychological Research, Practice, and Production: The Occupational Stress Problem

The accumulation of research findings now suggest a significant work stress problem, with implications for worker health, motivation and productivity, that warrants a concerted applied research effort at a local level and a strategy and policy response at a national level. Psychologists need to rethink prevailing paradigms that often separate their research and practice. We argue that a conducive production model that emphasizes action and knowledge, and reciprocal learning between academia, practitioners, and organizations may be the way forward for psychologists to respond effectively to the current work stress problems and other emergent organizational issues. Failure to do so may result in exacerbation of problems related to the psychological and social context of work, a slowed response to increased demands, and an ever decreasing practical utility of the profession.     

Critical issues in Muslim‐Christian relations: Theoretical,practical, dialogical,scholarly

In treating some critical issues in Muslim‐Christian relations at present and in the near future I would like to say something on the basis of what may be qualified as ‘critical realism’ on the one hand and ‘constructive partnership’ on the other. My purpose here is to identify some issues with which we have to cope when we want to improve relations between Muslims and Christians for times to come.     

Reduction of the “psychological refractory period”

The usual increase in reaction time which occurs when a reaction stimulus is preceded by one irrelevant stimulus was-reduced 30% by preceding the latter with a second irrelevant stimulus at certain critical intervals between stimuli. The interaction between the irrelevant stimuli, as measured by reaction time, has a different time course than the interaction implicit in tlte “psychological refractory period”.     

The interaction of state and trait aspects of self-focused attention affects genital, but not subjective, sexual arousal in sexually functional women

In this study we investigated the effects of state and trait aspects of self-focused attention on genital and subjective sexual arousal of sexually functional, healthy women during presentation of audiovisual erotic stimuli. Psychophysiological sexual response was measured as vaginal pulse amplitude using a vaginal photoplethysmograph. Experiential aspects of sexual arousal were measured both during stimulus presentation and retrospectively after stimulus offset. Trait level of sexual self-focus was measured with the Sexual Self-Consciousness Scale. State self-focus was induced by switching on a TV camera that pointed at the participant's face and upper torso. A manipulation check revealed that both groups experienced equally elevated levels of self-focused attention of their physical appearance. Induction of state self-focus per se did not affect genital responses, but an interaction effect of self-focus and participants' level of trait sexual self-focus was revealed. Compared with women with low scores on this trait, women with high scores exhibited smaller genital responses when state self-focus was induced. Both groups did not differ when no self-focus was induced. Increase of state self-focus did not affect subjective sexual arousal, but participants with a high level of trait sexual self-focus reported stronger subjective arousal, compared with those with low trait level. The results were discussed with reference to previous work in this field. Some implications for treatment of sexual arousal disorder were discussed.     

Children with developmental coordination disorder are equally able to generate force but show more variability than typically developing children

Several studies have suggested that children with developmental coordination disorder (DCD) have difficulties in the fine-tuning of manual force. However, parameterization of the generated force per se is hard to test under normal circumstances as movement planning and execution are also involved. In the present study, an isometric force production task was used to test the hypothesis that children with DCD have a decreased ability to scale force to a required force level and to maintain steady low to submaximal forces. We also tested if the developmental trends were different between the children with DCD and typically developing (TD) children. Twenty-four children with DCD and 24 matched TD children, divided over three age groups (7-9-11 years) participated in this study. Analysis of the data showed that DCD and TD children are equally able to adapt their generated force to the required levels, however DCD children produced a less steady force, even more variable than in the youngest TD children. These results suggest that problems in force control in children with DCD are caused by a higher level of inherent noise of the output system. Since younger DCD children are much more affected than older ones it is suggested that these children are able to learn a strategy to cope with their increased stochastic variability, especially at higher force levels.     

Do Humans Really Learn AnBn Artificial Grammars From Exemplars?

An important topic in the evolution of language is the kinds of grammars that can be computed by humans and other animals. Fitch and Hauser (F&H; 2004) approached this question by assessing the ability of different species to learn 2 grammars, (AB)(n) and A(n) B(n) . A(n) B(n) was taken to indicate a phrase structure grammar, eliciting a center-embedded pattern. (AB)(n) indicates a grammar whose strings entail only local relations between the categories of constituents. F&H's data suggest that humans, but not tamarin monkeys, learn an A(n) B(n) grammar, whereas both learn a simpler (AB)(n) grammar (Fitch & Hauser, 2004). In their experiments, the A constituents were syllables pronounced by a female voice, whereas the B constituents were syllables pronounced by a male voice. This study proposes that what characterizes the A(n) B(n) exemplars is the distributional regularities of the syllables pronounced by either a male or a female rather than the underlying, more abstract patterns. This article replicates F&H's data and reports new controls using either categories similar to those in F&H or less salient ones. This article shows that distributional regularities explain the data better than grammar learning. Indeed, when familiarized with A(n) B(n) exemplars, participants failed to discriminate A(3) B(2) and A(2) B(3) from A(n) B(n) items, missing the crucial feature that the number of As must equal the number of Bs. Therefore, contrary to F&H, this study concludes that no syntactic rules implementing embedded nonadjacent dependencies were learned in these experiments. The difference between human linguistic abilities and the putative precursors in monkeys deserves further exploration.     

Health Behaviors and Psychological Distress in Women Initiating BRCA1/2 Genetic Testing: Comparison with Control Population

The study objective was to compare breast cancer screening practices, lifestyle behaviors and psychological distress among 640 women initiating BRCA1/2 testing to those among 9,498 similarly-aged women from the general population. Health behaviors and psychological distress were reported in a self-administered questionnaire at pre-test genetic counseling. Regression analyses indicate that high-risk women were more frequently performing breast cancer screening and, in the case of those previously diagnosed with cancer, were more likely to be non-smokers and physically active than women from general population. However, women initiating BRCA1/2 testing were significantly more distressed than controls. Globally, high-risk women seemed to be well informed about recommendations for women who are at high risk and to have access to screening adapted to their risk level. Given their significant psychological distress, providing minimal psychosocial support to all women undergoing BRCA1/2 testing at pre-test genetic counseling is relevant.