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Ohne Zusammenfassung     

Characterization of long-term memory, resistance to extinction, and influence of temperament during two instrumental tasks in horses

The present study investigated the influence of temperament on long-term recall and extinction of 2 instrumental tasks in 26 horses. In the first task (backward task), horses learned to walk backward, using commands given by an experimenter, in order to obtain a food reward. In the second task (active avoidance task), horses had to cross an obstacle after a bell rang in order to avoid emission of an air puff. Twenty-two months after acquisition, horses exhibited perfect recall performance in both tasks. Accordingly, no influence of temperament on recall performance could be observed for either task. In contrast, in the absence of positive or negative outcomes, the horses’ ability to extinguish their response to either task was highly variable. Resistance to extinction was related to some indicators of temperament: The most fearful horses tended to be the most resistant to extinction in the backward task, while the least sensitive horses tended to be the most resistant to extinction in the active avoidance task. These findings reveal extensive long-term memory abilities in horses and suggest an influence of temperament on learning processes other than acquisition.     

Maternal Sensitivity: a Resilience Factor against Internalizing Symptoms in Early Adolescents Born Very Preterm?

Compared with full-terms, preterm individuals are more at risk from infancy to adulthood for developing internalizing symptoms. Early maternal interactive behavior, especially maternal sensitivity, has been found to be a resilience factor in the developmental outcome of preterm children. The present longitudinal study aimed at examining whether early interactive parenting behaviors have a long term impact on the internalizing symptoms of preterm-born young adolescents. A total sample of 36 very preterm and 22 full-term children participated in an 11-year follow-up study. Maternal interactive behavior was assessed during a mother–infant interaction when the infant was 18 months old. At 11 years, internalizing symptoms were assessed with the Child Behavior Checklist (CBCL). Hierarchical regression analyses revealed that the interaction between groups (preterm/full-term) and maternal sensitivity at 18 months significantly explained CBCL internalizing symptoms at 11 years (β = ?0.526; p < 0.05). Specifically, although prematurity was related to internalizing problems, preterm children with higher maternal sensitivity did not differ from their full-term-born peers on the CBCL internalizing problems domain. These results suggest that maternal sensitivity is a long-term resilience factor preventing the development of internalizing problems at early adolescence in very preterm individuals.     

Awareness of time distortions and its relation with time judgment: a metacognitive approach

The perception of time cannot be reduced to a simple percept produced by an internal clock. The aim of the present study was therefore to investigate the role of the individual consciousness of time on temporal judgments. In the present study, the participants' awareness of attention-related time distortions was assessed using a metacognitive questionnaire. The participants were also required to verbally judge a series of stimulus durations in a single or a dual task condition. The results revealed that time was underestimated in the dual task compared to the single task. However, the accuracy of time judgments improved in line with the participants' individual awareness of attentional time distortion: The more aware they were of the role of attention in time perception, the lower the time distortions they exhibited. Conscious awareness of time therefore plays a role in the accuracy of the time judgments made by human beings.     

An oscillatory mechanism for prioritizing salient unattended stimuli

To survive in a complex world, it is important that unattended, but salient, input can still draw one's attention. In this article, we suggest that posterior alpha oscillations (8-13Hz) provide a mechanism for prioritizing and ordering unattended visual input according to 'relevance'. Gamma oscillations (30-100Hz) that are phase-locked to the alpha oscillations keep competing unattended representations apart in time, thus creating a sequence of perceptual cycles. As inhibition gradually lowers within an alpha cycle, the ordered sequence of competing input is activated, producing a temporal phase code for saliency. The proposed mechanism is based on recent experiments indicating that the phase of alpha activity modulates perception and that alpha oscillations are produced by periodic pulses of inhibition.     

Deduction electrified: ERPs elicited by the processing of words in conditional arguments

This study investigates the ERP components associated with the processing of words that are critical to generating and rejecting deductive conditional Modus Ponens arguments (If P then Q; P//Therefore, Q). The generation of a logical inference is investigated by placing a verb in the minor premise that matches the one used in the antecedent of the conditional premise so that the inference can be carried out (If John is sleeping then he is snoring; John is sleeping). Rejections are examined by placing verbs that are associates of the verb that would make the conclusion valid (Conclusion ‘therefore John is dreaming’ in the example above). The inference generation phase was characterized by two ERP components, namely the P3b and the PSW. Rejections were associated with an N2 and a late positive component. The implications of these results regarding the processing of words in an inferential context are discussed.     

A cross-linguistic data bank for oral picture naming in Dutch, English, German, French, Italian, Russian, Spanish, and Swedish (PEDOI)

The well established effect of word frequency on adult's picture naming performance is now called into question. This is particularly true for variables which are correlated with frequency, as is the case of age of word acquisition. Since the work of [Carrol and White, 1973] there is growing agreement among researchers to confer an important role in lexical access to this variable. Indeed, it has been shown ( [Hodgson and Ellis, 1998]) that for normal English-speaking adults only the variables 'age-of-acquisition' and 'name agreement' are independent predictors of naming success among the various variables considered. However, when brain-damaged subjects with and without degenerative pathologies are studied, word frequency and word length as well as concept familiarity all give significant effects ( [Hirsh and Funnell, 1995]; [Lambon Ralph et al., 1998]; [Nickels and Howard, 1995]). Finally, it has been suggested that the production of specific error types may be related to such variables. According to [Nickels and Howard, 1994] the production of semantic errors is specifically affected by 'imageability' and in the recent study by [Kremin et al., 2001] 'age of acquisition' predicts (frank) word finding difficulties.