Habituation of exploratory activity to new stimuli, to the absence of a previously presented stimulus and to new contexts, in rats

Rats trained to run a shuttle-alleyway for food exhibited exploratory behaviour to a novel visual/tactual stimulus presented in a specific place of the alley. Intermittent presentation of the same stimulus in the same place resulted in reduction of the exploratory activity (habituation), both within and between sessions. The animals also directed exploratory activity to the absence of the previously presented stimulus at the place where the stimulus had been presented before; this latter response also habituated. The presentation (1) of the same stimulus to which the animals had already habituated in another place in the alleyway or when the animals were running in an opposite direction to the previous trials of stimulus presentation, or (2) of another stimulus, resulted, again, in the appearance of exploratory activity. These results lead to the conclusion that the animals code external events, store this information, and use it to detect spatial- and directional-contextual changes and to generate predictions about that specific environment.     

Properties of curvilinear vection

Approximately linear relationships were observed between contrast, spatial frequency, temporal frequency, or velocity of stimulation and perceived velocity of curvilinear vection—that is, a visually induced self-motion in a curved path. Similarly, linear relationships were also found between the perceived degree of curvature of curvilinear vection and spatial frequency or velocity of stimulation. Since the perceived velocity of curvilinear vection varies with contrast, spatial frequency, temporal frequency, and angular velocity, and the perceived degree of curvature of curvilinear vection varies only with spatial frequency and angular velocity, peripheral vision is not sufficient for computing accurately the curvilinear component of induced self-motion in a curved path. Concurrently, it was shown that the perceived direction of curvilinear vection is not always unambiguously perceived (Sauvan & Bonnet, 1989). Consequently, it is suggested that two different types of visual processing, which involve the peripheral or the central vision, underlie the processing of curvilinear vection.     

Extending Awareness of Catholic Healthcare Ethics Among Junior Clinicians: A Qualitative Study

Journal of Religion and Health - As Catholic healthcare organizations form a substantive part of healthcare delivery in the USA and Australia, ethical standards for Catholic health care were...     

Structure of personality pathology in normal and clinical samples: Spanish validation of the DAPP-BQ

Given that the DSM taxonomy of personality disorders is flawed by severe classificatory problems, the development of alternative classificatory systems, such as the Dimensional Assessment of Personality Pathology-Basic Questionnaire (DAPP-BQ), has now become a priority. This study examined the internal consistency, second-order factor structure, and criterion validity of a Spanish translation of the DAPP-BQ in two samples: subjects with personality disorder (n = 155) and subjects from the general population (n = 300). Alpha coefficients ranged satisfactorily from .75 to .93. Four second-order factors of Emotional Dysregulation, Dissocial Behavior, Inhibitedness, and Compulsivity were obtained, which were replicable between samples and identical to those reported in the literature. Finally, disordered subjects scored significantly higher than normal subjects on 17 of the 18 DAPP-BQ traits. Some pending issues in the construction of an alternative taxonomy of personality disorders are discussed.     

Large-scale brain systems in ADHD: beyond the prefrontal-striatal model

Attention-deficit/hyperactivity disorder (ADHD) has long been thought to reflect dysfunction of prefrontal-striatal circuitry, with involvement of other circuits largely ignored. Recent advances in systems neuroscience-based approaches to brain dysfunction have facilitated the development of models of ADHD pathophysiology that encompass a number of different large-scale resting-state networks. Here we review progress in delineating large-scale neural systems and illustrate their relevance to ADHD. We relate frontoparietal, dorsal attentional, motor, visual and default networks to the ADHD functional and structural literature. Insights emerging from mapping intrinsic brain connectivity networks provide a potentially mechanistic framework for an understanding of aspects of ADHD such as neuropsychological and behavioral inconsistency, and the possible role of primary visual cortex in attentional dysfunction in the disorder.     

Migration Related Socio-cultural Changes and e-Learning in a European Globalising Society

OECD figures (1998–2002) reveal a sharply increasing flow of foreign workers into European countries. Ethnic diversification has become a generalized matter of fact. At the same time, rapidly developing technology and ‘intellectual globalization’ processes—the world wide web—have also become a reality. This complex cluster of changes has an impact on the perceptions of the self and of the other. Multilayered belongings and paradoxical meanings enter into interethnic relations in sometimes most surprising and unpredictable ways from outside of the boundaries of local communities. But the developments also create new and very positive opportunities for education/schooling and social cohesion. The paper critically examines this changing context and also Europe’s educational responses to the new challenges: the European Socrates programme, the initiatives in the field of intercultural citizenship education and the issue of combating deprivation.

Contextual,but not auditory,fear conditioning is disrupted by neurotoxic selective lesion of the basal nucleus of amygdala in rats

The basolateral amygdala complex (BLA) is involved in acquisition of contextual and auditory fear conditioning. However, the BLA is not a single structure but comprises a group of nuclei, including the lateral (LA), basal (BA) and accessory basal (AB) nuclei. While it is consensual that the LA is critical for auditory fear conditioning, there is controversy on the participation of the BA in fear conditioning. Hodological and neurophysiological findings suggest that each of these nuclei processes distinct information in parallel; the BA would deal with polymodal or contextual representations, and the LA would process unimodal or elemental representations. Thus, it seems plausible to hypothesize that the BA is required for contextual, but not auditory, fear conditioning. This hypothesis was evaluated in Wistar rats submitted to multiple-site ibotenate-induced damage restricted to the BA and then exposed to a concurrent contextual and auditory fear conditioning training followed by separated contextual and auditory conditioning testing. Differing from electrolytic lesion and lidocaine inactivation, this surgical approach does not disturb fibers of passage originating in other brain areas, restricting damage to the aimed nucleus. Relative to the sham-operated controls, rats with selective damage to the BA exhibited disruption of performance in the contextual, but not the auditory, component of the task. Thus, while the BA seems required for contextual fear conditioning, it is not critical for both an auditory-US association, nor for the expression of the freezing response.     

Emotional responses to a negative emotion induction procedure in Borderline Personality Disorder

The aim of this study was to determine if patients with Borderline Personality Disorder (BPD) present higher emotional response than healthy controls in a laboratory setting. Fifty participants (35 patients with BPD and 15 healthy controls) underwent a negative emotion induction procedure (presentation of standardized unpleasant images). Subjective emotional responses were assessed by means of self-reported questionnaires while biological reactivity during the procedure was measured through levels of salivary cortisol (sCORT) and alphaamylase (sAA). Patients with BPD exhibited significant lower cortisol levels and higher sAA levels compared to controls. Self-reported emotional reactivity did not give rise to differences between groups but participants with BPD did present higher levels of negative emotional intensity at baseline and during the entire procedure. The findings do not give support to the emotional hyperreactivity hypothesis in BPD. However, BPD patients presented heightened negative mood intensity at baseline, which should be considered a hallmark of the disorder. Further studies using more BPD-specific emotion inductions are needed to confirm the trends observed in this study.