A matter of facts

We discuss the justification of Bickle's “ruthless” reductionism. Bickle intends to show that we know enough about neurons to draw conclusions about the “whole” brain and about the mind. However, his reductionism does not take into account the complexity of the nervous system and the fact that new properties emerge at each significant level of integration from the coupled functioning of elementary components. From a methodological point of view, we argue that neuronal and cognitive models have to exert a mutual constraint(MC) on each other. This approach would refuse to award any priority of cognitive approaches over neuroscience, and reciprocally, to refuse any priority of neuroscience over cognitive approaches. MC thus argues against radicalreductionism at the methodological level.     

Calcium signaling in mitral cell dendrites of olfactory bulbs of neonatal rats and mice during olfactory nerve Stimulation and beta-adrenoceptor activation

Synapses formed by the olfactory nerve (ON) provide the source of excitatory synaptic input onto mitral cells (MC) in the olfactory bulb. These synapses, which relay odor-specific inputs, are confined to the distally tufted single primary dendrites of MCs, the first stage of central olfactory processing. beta-adrenergic modulation of electrical and chemical signaling at these synapses may be involved in early odor preference learning. To investigate this possibility, we combined electrophysiological recordings with calcium imaging in olfactory bulb slices prepared from neonatal rats and mice. Activation of ON-MC synapses induced postsynaptic potentials, which were associated with large postsynaptic calcium transients. Neither electrical nor calcium responses were affected by beta-adrenergic agonists or antagonist. Immunocytochemical analysis of MCs and their tufted dendrites revealed clear immunoreactivity with antibodies against alpha1A (Cav2.1, P/Q-type) and alpha1B (Cav2.2, N-type), but not against alpha1C (Cav1.2, L-type) or alpha1D (Cav1.3, L-type) calcium channel subunits. Moreover, nimodipine, a blocker of L-type calcium channels, had no effect on either electrical or calcium signaling at ON-MC synapses. In contrast to previous evidence, we concluded that in neonatal rats and mice (P5-P8), mitral cells do not express significant amounts of L-type calcium channels, the calcium channel type that is often targeted by beta-adrenergic modulation. The absence of beta-adrenergic modulation on either electrical or calcium signaling at ON-MC synapses of neonatal rats and mice excludes the involvement of this mechanism in early odor preference learning.     

Update Semantics of Security Protocols

We present a model-theoretic approach for reasoning about security protocols, applying recent insights from dynamic epistemic logics. This enables us to describe exactly the subsequent epistemic states of the agents participating in the protocol, using Kripke models and transitions between these based on updates of the agents’ beliefs associated with steps in the protocol. As a case study we will consider the SRA Three Pass protocol and discuss the Wide-Mouthed Frog protocol.     

Effects of ontogeny on performance of rats in a novel object-recognition task

The current experiment investigated ontogenetic forgetting on a novel object-recognition task similar to that of Besheer and Bevins. 18-day-old pups (n = 49) and adult (n = 29) rats were tested at two retention intervals (1 min. or 120 min.). By employing exclusion criteria which demanded minimum amounts of object exploration at training and test, the performance of 18-day-old pups but not that of adults was significantly impaired at 120 min. relative to 1 min. Analysis indicated that the ontogeny of the learning and memory measured in novel object recognition follows a developmental trend similar to that of other forms of learning, with older animals remembering more and thus performing better than younger animals. Unfortunately, given the extreme variability inherent to the task and large N necessary to achieve significance, the use of this task in studies of learning, memory, and development is discouraged.     

Beliefs in personality disorders: a test with the personality disorder belief questionnaire

The hypothesis that each personality disorder (PD) is characterized by a specific set of beliefs was tested in a sample of 643 subjects, including non-patient controls, axis-I and axis-II patients, diagnosed with SCID-I and -II interviews. Beliefs of six PDs (avoidant, dependent, obsessive-compulsive, paranoid, histrionic, borderline) were assessed with the Personality Disorder Belief Questionnaire (PDBQ). Factor analyses supported the existence of six hypothesized sets of beliefs. Structural equation modeling (SEM) supported the hypothesis that each PD is characterized by a specific set of beliefs. Path coefficients were however in the medium range, suggesting that PDs are not solely determined by beliefs. Nevertheless, empirically derived cutoff scores of the six belief subscales were reasonably successful in classifying subjects, percentages ranging form 51% to 83%. It appeared that there was a monotonical increase in scores on each belief subscale from non-patient controls, to patients without any PD, to patients with PDs (other than the pertinent PD), to patients with the pertinent PD. This suggests that PD-related beliefs are at least partly associated with (personality) psychopathology in general. Another explanation is that many patients' position on the underlying dimensions is not high enough to lead to a DSM PD diagnosis, but high enough to lead to an elevated belief score.     

General self-efficacy,dental anxiety and multiple fears among 20-year-olds in Norway

This paper examines the extent to which low general self-efficacy and painful dental and medical experiences are related to dental anxiety, multiple fears and to avoidance of dental care. A total of 754 20-year-olds completed a series of questionnaires, including the General Self-efficacy Scale (GSE), Geer Fear Scale (GFS) and Dental Fear Survey (DFS). Females had lower self-efficacy, higher dental anxiety and higher scores on the GFS than males. Multivariate analyses (linear stepwise regression) indicated that painful dental experiences, a high score on the GFS and negative opinions about own dental health explained 37% of the variance in DFS scores. Self-efficacy had no predictive power for dental anxiety, and only dental anxiety had predictive power for dental avoidance behavior. Thirty-eight percent of the total variance in GFS scores was explained by the following variables: being a female, high dental anxiety (DFS), low general self-efficacy (GSE) and low educational level of the mother.     

School-age children's perceptions of a person who stutters

The present study examined the perceptions school-age children have of stutterers. Four groups of fourth and fifth grade students viewed a videotape with either the speaker stuttering or not stuttering while reading a poem. A semantic differential scale of bi-polar adjective pairs was used to rate the speaker on intelligence and personality traits. The current study found that there is a significant difference between school-age children's perceptions of stutterers and nonstutterers with the ratings for the disfluent speaker more negative than the ratings for the fluent speaker. It was found that children did not rate personality and intelligence related traits differently. This information can be used to validate the need for education regarding stuttering for children and those who work with children. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to (1). identify perceptions of stutterers by a variety of groups; (2). discuss the implications of research on perceptions of stutterers; and (3). compare/contrast children and adults and their perceptions.     

Low alpha power (7.5–9.5 Hz) changes during positive and negative affective learning

There is evidence that the positive and the negative word lists of the Affective Auditory Verbal Learning Test (AAVL) are useful with regard to mood induction. To date, however, changes in brain activation, as indicated by quantitative electroencephalographic recording, have not been examined. Thus, changes in low alpha power (7.5-9.5 Hz) were examined during and after completion of the positive or the negative learning list of the AAVL among 37 undergraduate men and women. Three primary findings from the study include the following: (1) Previously reported recall patterns were replicated; (2) participants who completed the negative list reported a significant decline in mood state at the end of the session; and (3) participants who completed the negative word list evidenced a significant reduction in low alpha power (in comparison with baseline) within the parietal regions. The findings noted above are seemingly counter to contemporary theories of mood regulation (i.e., asymmetrical changes in anterior activity, rather than changes in parietal regions). Although the AAVL may have limited utility as a tool for mood induction, it may serve as a functional tool for examination of the cerebral processes associated with affective verbal memory.     

Strategic aspects of numerosity judgment: the effect of task characteristics

In previous investigations we documented that people use several strategies to determine different numerosities of blocks that are presented in a square grid. One of these strategies is the clever subtraction strategy, wherein the number of empty squares in the grid is subtracted from the total number of squares in the grid. In the present study we investigated participants' flexibility in strategy use when varying the shape of the grid. Analysis of the results in terms of the theoretical framework of Lemaire and Siegler (1995) regarding strategic change shows that this contextual variable affected the frequency, execution time, and accuracy of subjects' use of the subtraction strategy. The usefulness of this framework for analyzing the nature of the adaptation to contextual variations is discussed. From a methodological point of view, this study documents the potential of Beem's (1993, 1999) segmented linear regression models for assessing subjects' strategy use in cognitive tasks.