A non-parametric Bayesian prior for causal inference of auditory streaming.

traditionally been modeled using a mechanistic approach. The problem however is essentially one of source inference – a problem that has recently been tackled using statistical Bayesian models in visual and auditory-visual modalities. Usually the models are restricted to performing inference over just one or two possible sources, but human perceptual systems have to deal with much more complex scenarios. To characterize human perception we have developed a Bayesian inference model that allows an unlimited number of signal sources to be considered: it is general enough to allow any discrete sequential cues, from any modality. The model uses a non-parametric prior, hence increased complexity of the signal does not necessitate more parameters. The model not only determines the most likely number of sources, but also specifies the source that each signal is associated with. The model gives an excellent fit to data from an auditory stream segregation experiment in which the pitch and presentation rate of pure tones determined the perceived number of sources

Studying strategies and types of players:Experiments, logics and cognitive models

How do people reason about their opponent in turn-taking games? Often, people do not make the decisions that game theory would prescribe. We present a logic that can play a key role in understanding how people make their decisions, by delineating all plausible reasoning strategies in a systematic manner. This in turn makes it possible to construct a corresponding set of computational models in a cognitive architecture. These models can be run and fitted to the participants’ data in terms of decisions, response times, and answers to questions. We validate these claims on the basis of an earlier game-theoretic experiment about the turn-taking game “Marble Drop with Surprising Opponent”, in which the opponent often starts with a seemingly irrational move. We explore two ways of segregating the participants into reasonable “player types”. The first way is based on latent class analysis, which divides the players into three classes according to their first decisions in the game: Random players, Learners, and Expected players, who make decisions consistent with forward induction. The second way is based on participants’ answers to a question about their opponent, classified according to levels of theory of mind: zero-order, first-order and second-order. It turns out that increasing levels of decisions and theory of mind both correspond to increasing success as measured by monetary awards and increasing decision times. Next, we use the logical language to express different kinds of strategies that people apply when reasoning about their opponent and making decisions in turn-taking games, as well as the ‘reasoning types’ reflected in their behavior. Then, we translate the logical formulas into computational cognitive models in the PRIMs architecture. Finally, we run two of the resulting models, corresponding to the strategy of only being interested in one’s own payoff and to the myopic strategy, in which one can only look ahead to a limited number of nodes. It turns out that the participant data fit to the own-payoff strategy, not the myopic one. The article closes the circle from experiments via logic and cognitive modelling back to predictions about new experiments

The Relationship between Regular Sports Participation and Vigilance in Male and Female Adolescents

The present study investigated the relationship between regular sport participation (soccer) and vigilance performance. Two groups of male and female adolescents differentiated in terms of their sport participation (athletes, n = 39, and non-athletes, n = 36) took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In the other session, participants completed the Psychomotor Vigilance Task (PVT) to evaluate their vigilance performance. Perceived arousal prior to the task and motivation toward the task were also measured in the PVT session. The results revealed that athletes had better cardiovascular fitness and showed better performance in the PVT. However, correlation analyses did not show any significant relationship between cardiovascular fitness and performance in the PVT. Athletes showed larger scores in motivation and perceived arousal measures with respect to non-athletes, although, once again, these variables were not correlated with PVT performance. Gender differences were observed only in the Leger test, with males showing greater fitness level than females. The major outcome of this research points to a positive relationship between regular sport participation and vigilance during adolescence. This relationship did not seem to be influenced by gender, perceived arousal, motivation toward the task or cardiovascular fitness. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between physical activity and cognitive functioning.This research was supported by a Spanish Ministerio de Educación y Cultura (https://sede. educacion.gob.es) predoctoral grant (FPU13-05605) to the first author, and project research grants: Junta de Andalucia Proyecto de Excelencia SEJ-6414 (http://www.juntadeandalucia.es) and Ministerio de Economía y Competitividad PSI2013-46385 (http://www.mineco.gob.es) to DS and FH

Traumatic experiences and post-traumatic stress disorder among elderly Germans: results of a representative population-based survey

BACKGROUND: Only a few population-based studies on the epidemiology of post-traumatic stress disorders (PTSDs) are available to date. Most of the existing studies are from the U.S.A. Against the background of World War II, the extent and long-term effects of war-related traumatic experiences in the German elderly population are of special interest. Nevertheless, population-based data on this topic are lacking to date. METHODS: This study examines the occurrence of traumatic experiences and the prevalence rates of PTSD according to DSM-IV and of partial PTSD in a randomly selected sample of the German general population aged 60 years and over (N = 814) using self-rating instruments. RESULTS: PTSD is apparent in 3.4%; when partial post-traumatic stress syndromes are included, a total of 7.2% of the aged population are involved. The most common individual symptoms resulting from war-induced trauma are avoidance of thoughts and feelings, sleep disturbances, distressing dreams and intrusive thoughts. The most frequently mentioned traumatic experiences of the generation examined in this study were war-related trauma experienced as children or in early adulthood during World War II. As a person's age increases, so does the prevalence of war-related traumatic experiences. There are some gender differences in traumatic experiences, but not in post-traumatic symptoms. CONCLUSION: The results emphasize the importance of war-related traumatic experiences from World War II in the German elderly population and their impact on the prevalence of PTSD more than 60 years later

Subjektive Gesundheit bei älteren Menschen

The Nottingham Health Profile (NHP ) is a widely used instrument to measure subjective health in clinical research. However, there are no age-specific norms for older adults in Germany. The present study was conducted to analyze the psychometric properties of the German version of the Nottingham Health Profile (NHP) in older people. Age-specific reference values for the elderly are presented. Subjects were drawn from the general population of older German people aged 61 to 95 years (n=630; mean age 69.5 years; 55.7% female). Five of the six NHP scales revealed a good internal consistency (.70<=alpha<=.92). The subscales (with the exception of the subscale social isolation) showed moderate relations with instruments measuring somatization disorders and subjective body complaints (Screening for Somatoform Disorders SOMS ); Giessen Subjective Complaints List GBB-24 ). Compared to younger subjects, subjective health decreases with age. Therefore age-specific reference data for older people are necessary. Differential reference data are reported for four age groups above 60 years of age and for male and female older people. The outcome confirms that the NHP is a reliable, valid instrument to measure subjective health in older people.Das Nottingham Health Profile (NHP) ist ein weit verbreitetes Verfahren zur Erfassung subjektiver Gesundheit in der klinischen Forschung. Für den deutschsprachigen Bereich liegen aber bislang noch keine altersspezifischen Normwerte für die ältere Bevölkerung vor. Die vorliegende Studie prüft die psychometrische Qualität der deutschsprachigen Version des Nottingham Health Profile (NHP) in der Anwendung bei älteren Menschen und präsentiert altersspezifische Referenzwerte. Die Stichprobe stammt aus der deutschen Allgemeinbevölkerung und umfasst Personen im Alter von 61 bis 95 Jahre (n=630; Durchschnittsalter 69,5 Jahre, 55,7% weiblich). Fünf der sechs NHP-Skalen weisen eine gute interne Konsistenz auf (,70<=alpha<=,92). Die Subskalen (mit Ausnahme der Subskala Soziale Isolation) zeigen mittlere Zusammenhänge mit Instrumenten zur Erfassung somatoformer Störungen und subjektiver Körperbeschwerden (Sreening für Somatoforme Störungen SOMS; Giessener Beschwerdebogen GBB-24). Im Vergleich mit jüngeren Menschen nimmt die subjektive Gesundeit im höheren Lebensalter ab. Dies bestätigt die Notwendigkeit altersspezifischer Referenzwerte für Ältere. Für vier Altersgruppen über 60 Jahre sowie für Frauen und Männer werden differenzierte Referenzwerte dargestellt. Die Ergebnisse bestätigen, dass der NHP ein reliables, valides Instrument zur Erfassung subjektiver Gesundheit bei Älteren ist

Effects of transmission perturbation in the cultural evolution of language

Two factors seem to play a major role in the cultural evolution of language. On the one hand, there is pressure towards efficient transfer of information. On the other hand, languages are learned repeatedly and will therefore show traces of systematic stochastic disturbances of the transmission of linguistic knowledge. A lot of attention has been paid to the effects of learning biases on the transmission of language, but there is reason to expect that the class of relevant transmission perturbations is much larger. This paper therefore explores some potential effects of transmission noise due to errors in the observation of states of the world. We look at three case studies on vagueness, meaning deflation, and underspecified lexical meaning. These studies suggest that transmission perturbations other than learning biases might help explain attested linguistic patterns and that perturbations due to perceptual noise may even produce effects very similar to learning biases