Exploiting redundancy for flexible behavior: unsupervised learning in a modular sensorimotor control architecture

Autonomously developing organisms face several challenges when learning reaching movements. First, motor control is learned unsupervised or self-supervised. Second, knowledge of sensorimotor contingencies is acquired in contexts in which action consequences unfold in time. Third, motor redundancies must be resolved. To solve all 3 of these problems, the authors propose a sensorimotor, unsupervised, redundancy-resolving control architecture (SURE_REACH), based on the ideomotor principle. Given a 3-degrees-of-freedom arm in a 2-dimensional environment, SURE_REACH encodes 2 spatial arm representations with neural population codes: a hand end-point coordinate space and an angular arm posture space. A posture memory solves the inverse kinematics problem by associating hand end-point neurons with neurons in posture space. An inverse sensorimotor model associates posture neurons with each other action-dependently. Together, population encoding, redundant posture memory, and the inverse sensorimotor model enable SURE_REACH to learn and represent sensorimotor grounded distance measures and to use dynamic programming to reach goals efficiently. The architecture not only solves the redundancy problem but also increases goal reaching flexibility, accounting for additional task constraints or realizing obstacle avoidance. While the spatial population codes resemble neurophysiological structures, the simulations confirm the flexibility and plausibility of the model by mimicking previously published data in arm-reaching tasks.     

National intelligence and suicide rate across Europe: an alternative test using educational attainment data

National mean scores on a historical knowledge test (taken as a proxy for intelligence), stemming from representative samples of male (and female) 9th-grade school students from 26 European countries in a 1999 report by Wilberg and Lynn, were significantly positively associated with the national male (and female) suicide rates, independent of the general quality-of-living conditions in these countries. This finding replicates previous evidence from cross-national studies (by Lester and by Voracek), of a correspondence of higher national IQ to higher suicide rates, with an alternative measure of national IQ that is independent of the national IQ estimates recently published by Lynn and Vanhanen which have been used in prior studies.     

Cross-cultural comparison of motivation to learn in physical education: Japanese vs Swedish schoolchildren

The present study compared differences between Japanese and Swedish schoolchildren in learning motivation-related variables in physical education. The subjects were 1,562 Japanese fifth and sixth graders (776 boys and 786 girls) ranging in age from 10 to 12 years and 573 Swedish fifth graders (306 boys and 267 girls) from 10 to 13 years (M = 11.4, SD = 0.5). They completed three questionnaires to evaluate the children's learning motivation, factors supporting motivation to learn, and preferences of learning behavior. The questionnaires were taken from Nishida's Diagnosis of Learning Motivation in Physical Education Test, a multidimensional and comprehensive test that measures learning motivation. A 2 x 2 (country by sex) multivariate analysis of variance indicated both Swedish boys and girls scored significantly higher than the Japanese children on most subscales. Results were discussed in relation to differences in the sports environment and culture of the two countries.     

Psychometric properties and correlates of the Lester-Bean Attribution of Causes to Suicide Scale (German form)

Psychometric properties and correlates of the German form of Lester and Bean's 1992 Attribution of Causes to Suicide Scale, of 18 items tapping into lay theories of suicide (intrapsychic problems, interpersonal conflicts, and societal forces as causes), were investigated in a sample of the general population in Austria (n=156). The three attributional dimensions presented moderate internal consistencies and the 18 items appeared to be factorially orderly, as indicated by exploratory factor analysis. Previous results were replicated, with positive interrelations among all three dimensions, but these were largely confined to men. Societal causes of suicide were significantly less frequently endorsed than intrapsychic or interpersonal causes. Respondents' sex, intelligence, and knowledge about suicide were unrelated, and scores on the Big Five personality factors and social desirability were largely unrelated to the three dimensions. Endorsing intrapsychic causes to suicide was correlated with advanced age, religiosity, and conservative political orientation, and the three dimensions entertained meaningful associations with locus of control (internality, social externality, and fatalistic externality). All observed demographic and attitudinal correlates were, however, of modest magnitude. Implications of the findings and directions for further inquiry are discussed.     

Suggestion overrides the Stroop effect in highly hypnotizable individuals

Cognitive scientists distinguish between automatic and controlled mental processes. Automatic processes are either innately involuntary or become automatized through extensive practice. For example, reading words is a purportedly automatic process for proficient readers and the Stroop effect is consequently considered the "gold standard" of automated performance. Although the question of whether it is possible to regain control over an automatic process is mostly unasked, we provide compelling data showing that posthypnotic suggestion reduced and even removed Stroop interference in highly hypnotizable individuals. Drawing on a large sample of highly hypnotizable participants, we examined the effects of suggestion on Stroop performance both with and without a posthypnotic suggestion to perceive the input stream as meaningless symbols. We show that suggestion administered to highly hypnotizable persons significantly reduced Stroop interference and derailed a seemingly automatic process.     

Health Beliefs and Behaviors of Women Who Have Received Genetic Counseling For Breast Cancer

There are both genetic and behavioral risk factors for breast cancer, but the interaction between these factors is not clear. Little is known about the impact of receiving genetic risk information for breast cancer on behaviors such as diet and physical activity. Seven focus groups were conducted with 23 women who had recently received genetic counseling for breast cancer, in order to explore health beliefs and behaviors following genetic counseling. Findings revealed that there was much confusion and uncertainty about the associations between health behaviors and breast cancer risk, and participants reported that receiving genetic counseling had little impact on health protective behaviors. Further research is required to understand variation in response to genetic risk information, and to assess the impact of providing additional information regarding lifestyle factors.     

Clinical Effectiveness of the LE<Superscript>3</Superscript>AN Program: A Military Healthy Lifestyle Program

For several decades, obesity has been a major health concern within the general population of the United States as well as within the unique military population. Unlike the civilian sector, military service requires individuals to meet weight and body fat standards. In order to assist overweight military personnel return to standards, Tripler Army Medical Center initiated the LE³AN Program. LE³AN is a one-week, day-treatment, cognitive-behavioral weight management program coupled with 12 months of weekly follow-up. Baseline data was collected on 387 consecutive participants. Despite physical fitness training and required standards in each military service, the average BMIs for men and women were in the obese range, with male participants’ BMIs significantly higher than women’s (34.3 vs 31.9, p<.005). One year outcome data was collected from 167 participants, i.e. 43.2% of treatment initiators. Among participants who completed treatment, men maintained a 6.56% loss of their initial weight while women maintained a 7.35% loss. Over a quarter, 26.6%, of those who started the program (but did not complete it) maintained at least a 5% weight loss at one year, while 61.6% of treatment completers maintained 5% weight losses. The opinions expressed in this article reflect the views of the authors and not those of the Department of Defense or the U.S. Army.     

An evaluation of in situ training to teach sexual abuse prevention skills to women with mental retardation

The current study evaluated a behavioral skills training (BST) program in combination with in situ training to teach sexual abuse prevention skills to five women with mild to moderate mental retardation. In situ assessments were conducted following BST and in situ training sessions were conducted for those who were unable to demonstrate the skills in the natural setting. The results showed that generalization of the safety skills to the natural setting occurred for three of the five participants following one to two in situ training sessions. One participant required 12 in situ training sessions and three booster training sessions to reach criterion level. Three of four participants assessed 1 month following training maintained the skills. Copyright © 2007 John Wiley & Sons, Ltd.     

Behavioral characterization of a transection of dorsal CA3 subcortical efferents: comparison with scopolamine and physostigmine infusions into dorsal CA3

Cholinergic projections from the medial septum and diagonal band of Broca into the hippocampus have long been implicated in learning and memory. Projections from CA3 to neurons in the medial septum and the diagonal band of Broca have been anatomically characterized. The present experiments were designed to evaluate interactions between the dorsal CA3 subcortical efferents and the cholinergic efferents from the medial septum and diagonal band of Broca for spatial and nonspatial (visual object) novelty detection in the rat. In Experiment 1, physostigmine and scopolamine (both 0.4 microL at 30 microM) were infused into dorsal CA3 and animals were tested on a spatial and nonspatial (visual object) novelty detection paradigm. Scopolamine infusions into dorsal CA3 caused deficits for both spatial and nonspatial (visual object) novelty detection. Physostigmine infusions into dorsal CA3 enhanced both spatial and nonspatial (visual object) novelty detection. These data support models proposing that acetylcholine may control the dynamics for encoding, consolidation, and retrieval in the hippocampus. In Experiment 2, a selective transection of dorsal CA3 efferents in the fimbria resulted in deficits for spatial and nonspatial (visual object) novelty detection. These deficits were similar to the deficits caused by scopolamine infusions into dorsal CA3. These data demonstrate that dorsal CA3 and the medial septum/diagonal band of Broca interact, and that dorsal CA3 influences cholinergic inputs into the hippocampus to facilitate encoding.     

Majority versus minority influence and prediction of behavioral intentions and behavior

Two experiments examined the effects of majority and minority influence on attitude-consistent behavioral intentions. In the first experiment, when attitudes were changed via minority influence there was a greater likelihood to engage in an attitude-consistent behavioral intention than when attitudes were changed via majority influence. This suggests that minority influence leads to stronger attitudes (based on systematic processing) that are more predictive of behavioral intentions, while attitude change via majority influence is due to compliance through non-systematic processing. Further support for this interpretation comes from the finding that the amount of message-congruent elaboration mediated behavioral intention. When there was no attitude change, there was no impact on behavioral intention to engage in an attitude-consistent behavior. Experiment 2 explored the role of personal relevance of the topic and also included a real behavioral measure. When the topic was of low personal relevance, the same pattern was found as Experiment 1. When the topic was of high personal relevance, thus increasing the motivation to engage in systematic processing, attitudes changed by both a majority and minority source increased behavioral intention and actual behavior. The results are consistent with the view that both majorities and minorities can lead to different processes and consequences under different situations.