A behavior-based circuit model of how outcome expectations organize learned behavior in larval Drosophila

Drosophila larvae combine a numerically simple brain, a correspondingly moderate behavioral complexity, and the availability of a rich toolbox for transgenic manipulation. This makes them attractive as a study case when trying to achieve a circuit-level understanding of behavior organization. From a series of behavioral experiments, we suggest a circuitry of chemosensory processing, odor-tastant memory trace formation, and the "decision" process to behaviorally express these memory traces--or not. The model incorporates statements about the neuronal organization of innate vs. conditioned chemosensory behavior, and the types of interaction between olfactory and gustatory pathways during the establishment as well as the behavioral expression of odor-tastant memory traces. It in particular suggests that innate olfactory behavior is responsive in nature, whereas conditioned olfactory behavior is captured better when seen as an action in pursuit of its outcome. It incorporates the available neuroanatomical and behavioral data and thus should be useful as scaffold for the ongoing investigations of the chemo-behavioral system in larval Drosophila.     

Visuo-spatial path learning,stress, and cortisol secretion following military cadets’ first parachute jump: the effect of increasing task complexity

The present field experiment examined how multi-trial visuo-spatial learning and memory performance are impacted by excessive arousal, instigated by a potentially life-threatening event (i.e., a first parachute jump). Throughout a parachute training activity, subjective and neuroendocrine (i.e., cortisol) stress levels were assessed of 61 male military cadets who were randomly assigned to a control (n = 30) or a jump stress condition (n = 31). Post-stress learning and memory capacity was assessed with a 10-trial path-learning task that permitted emergence of learning curves. Pre-activity cortisol concentrations indicated a significant neuroendocrine anticipatory stress response in the stress group. Following parachuting, subjective stress levels and salivary cortisol reactivity differed significantly between groups. Visuo-spatial path-learning performance was impaired significantly after jump stress exposure, relative to the control group. Moreover, examination of the learning curves showed similar learning and memory performance at onset of the trials, with curves bifurcating as the task became more complex. These findings are in accordance with leading theories that acknowledge a moderating effect of task complexity. In sum, the present study extends knowledge concerning anticipatory stress effects, endogenously instigated cortisol reactivity, and the influence of extreme arousal on visuo-spatial path learning.     

Sensitivity to initial values in full non‐parametric maximum‐likelihood estimation of the two‐parameter logistic model

Parameters of the two‐parameter logistic model are generally estimated via the expectation–maximization (EM) algorithm by the maximum‐likelihood (ML) method. In so doing, it is beneficial to estimate the common prior distribution of the latent ability from data. Full non‐parametric ML (FNPML) estimation allows estimation of the latent distribution with maximum flexibility, as the distribution is modelled non‐parametrically on a number of (freely moving) support points. It is generally assumed that EM estimation of the two‐parameter logistic model is not influenced by initial values, but studies on this topic are unavailable. Therefore, the present study investigates the sensitivity to initial values in FNPML estimation. In contrast to the common assumption, initial values are found to have notable influence: for a standard convergence criterion, item discrimination and difficulty parameter estimates as well as item characteristic curve (ICC) recovery were influenced by initial values. For more stringent criteria, item parameter estimates were mainly influenced by the initial latent distribution, whilst ICC recovery was unaffected. The reason for this might be a flat surface of the log‐likelihood function, which would necessitate setting a sufficiently tight convergence criterion for accurate recovery of item parameters.     

Religion in a private igloo? A critical dialogue with Richard Rorty

It is still a popular philosophical position to call for a strict “separationism” concerning the private and the public sphere when it comes to religious convictions. Richard Rorty is one prominent supporter of this claim. The traditional critique against this division is mostly built on a particular characterization of religion that is at odds with Rortian assumptions. In this article, however, Rorty is criticized on his own terms turning pragmatically the objection to a fully internal one. What Rorty values most, namely a tolerant and ironic liberalism as the capacity to describe oneself in new and interesting ways is precisely the role, I argue, that religious faith could play under “neo-liberal” conditions.     

Treatment manuals: use in the treatment of bulimia nervosa

As psychology has moved toward emphasizing evidence-based practice, use of treatment manuals has extended from research trials into clinical practice. Minimal research has directly evaluated use of manuals in clinical practice. This survey of international eating disorder professionals examined use of manuals with 259 clinicians’ most recent client with bulimia nervosa. Although evidence-based manuals for bulimia nervosa exist, only 35.9% of clinicians reported using a manual. Clinicians were more likely to use a manual if they were younger; were treating an adult client; were clinical psychologists; were involved in research related to eating disorders; and endorsed a cognitive-behavioral orientation. Clinicians were less likely to use a manual if they provided eclectic psychotherapy that incorporated multiple psychotherapeutic approaches. We conclude that psychotherapy provided in clinical practice often does not align with the specific form validated in research trials, and “eclecticism” is at odds with efforts to disseminate manuals into clinical practice.     

Intelligence,social class of origin,childhood behavior disturbance and education as predictors of status attainment in midlife in men: The Aberdeen Children of the 1950s study

In a birth cohort of 6281 men from Aberdeen, Scotland, social class of origin, childhood intelligence, childhood behavior disturbance and education were examined as predictors of status attainment in midlife (46 to 51 years). Social class of origin, intelligence and behavior disturbance were conceptualized as correlated predictors, whose effects were hypothesized to be partially mediated by educational qualifications. A structural equation model using Full Information Maximum Likelihood estimation confirmed that education had the strongest direct effect on status attainment at midlife. Furthermore, education partially mediated the effects of social class of origin and childhood intelligence, and fully mediated the effects of behavior disturbance on status attainment. Social class of origin, childhood intelligence and behavior disturbance were strongly inter-correlated. After controlling for these associations, educational and social status attainments were influenced to a considerably greater extent by childhood intelligence than by social class of origin.     

A Validation Study of the Resilience Scale for Adolescents (READ)

In this study, the validity of the recently developed 28-item Resilience Scale for Adolescents (READ) was examined. Survey data from a representative sample of 6,723 Norwegian senior high school students between 18 and 20 years of age were used for this purpose. Validity and reliability were investigated by means of exploratory and confirmatory factor analysis, correlations with other relevant variables, and internal consistency measures. The results supported the construct and convergent validity of the five factors of a modified 23-item version of the scale, which also yielded acceptable psychometric properties. The paper concludes that the modified READ is a valid measure assessing relevant resilience factors with relatively few items, thereby serving as a valuable tool in resilience and risk-factor research.     

Parent’s Perception of Their First Encounter with Child and Adolescent Psychiatry

Parents who came with their child to Child and Adolescent Psychiatry (CAP) for the first time were interviewed 1–2 weeks afterwards in the presence of the child and the therapists. In a grounded theory analysis they revealed uncertainty about their role in the first meeting as well as of future planning. What had been important to them were aspects like communication, sharing perspectives, and the reformulation of problems.     

The effect of spatial frequency content on parameters of eye movements

Two experiments were conducted to examine the influence of the spatial frequency content of natural images on saccadic size and fixation duration. In the first experiment 10 pictures of natural textures were low-pass filtered (0.04-0.76 cycles/deg) and high-pass filtered (1.91-19.56 cycles/deg) and presented with the unfiltered originals in random order, each for 10 s, to 18 participants, with the instruction to inspect them in order to find a suitable name. The participants' eye movements were recorded. It was found that low-pass filtered images resulted in larger saccadic amplitudes compared with high-pass filtered images. A second experiment was conducted with natural stimuli selected for different power spectra which supported the results outlined above. In general, low-spatial frequencies elicit larger saccades associated with shorter fixation durations whereas high-spatial frequencies elicit smaller saccades with longer fixation durations.