Behavioral studies on bilingual learning have revealed cognitive costs (lower accuracy and/or higher processing time) when the language of application differs from the language of learning. The aim ...of this functional magnetic resonance imaging (fMRI) study was to provide insights into the cognitive underpinnings of these costs (so‐called language‐switching costs) in mathematics. Twenty‐nine bilingual adults underwent a 4‐day arithmetic training in one language, followed by an fMRI test session in which they had to solve the trained problems in both languages. Language‐switching costs were accompanied by increased activation in areas associated with magnitude processing (intraparietal sulcus), visuo‐spatial imagery (precuneus), numerical stimulus recognition (fusiform gyrus) and executive functions (frontal areas). These findings suggest that language‐switching costs in arithmetic are due to additional numerical information processing. Bilingual education programs need to take these findings into account to reduce language‐switching costs in order to fully exploit the potential of bilingual learning.
► We investigated selection of meanings of polar homonyms in a neutral context. ► Priming by masked and visible homonyms was measured at prime-target SOAs of 100–1500ms. ► With visible homonyms, ...there was positive priming of two meanings at short SOAs. ► With masked homonyms, there was negative priming for the rare and positive priming for the frequent meaning across SOAs. ► No parallel activation but selective access of word meaning when the word is masked.
Homonyms, i.e. ambiguous words like ‘score’, have different meanings in different contexts. Previous research indicates that all potential meanings of a homonym are first accessed in parallel before one of the meanings is selected in a competitive race. If these processes are automatic, these processes of selection should even be observed when homonyms are shown subliminally. This study measured the time course of subliminal and supraliminal priming by homonyms with a frequent (dominant) and a rare (subordinate) meaning in a neutral context, using a lexical decision task. In the subliminal condition, priming across prime-target asynchronies ranging from 100ms to 1.5s indicated that the dominant meaning of homonyms was facilitated and the subordinate meaning was inhibited. This indicates that selection of meaning was much faster with subliminal presentation than with supraliminal presentation. Awareness of a prime might decelerate an otherwise rapid selection process.
Annealing study of a bistable cluster defect Junkes, Alexandra; Eckstein, Doris; Pintilie, Ioana ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2010, Letnik:
612, Številka:
3
Journal Article
Recenzirano
This work deals with the influence of neutron and proton induced cluster related defects on the properties of n-type silicon detectors. Defect concentrations were obtained by means of Deep Level ...Transient Spectroscopy (DLTS) and Thermally Stimulated Current (TSC) technique, while the full depletion voltage and the reverse current were extracted from capacitance–voltage (
C–
V) and current–voltage (
I–
V) characteristics.
The annealing behaviour of the reverse current can be correlated with the annealing of the cluster related defect levels labeled
E
4
a
and
E
4
b
by making use of their bistability. This bistability was characterised by isochronal and isothermal annealing studies and it was found that the development with increasing annealing temperature is similar to that of divacancies. This supports the assumption that
E
4
a
and
E
4
b
are vacancy related defects. In addition we observe an influence of the disordered regions on the shape and height of the DLTS or TSC signals corresponding to point defects like the vacancy-oxygen complex.
The prospect of reward changes how we think and behave. We investigated how this occurs in the brain using a novel continuous performance task in which fluctuating reward expectations biased ...cognitive processes between competing spatial and verbal tasks. Critically, effects of reward expectancy could be distinguished from induced changes in task-related networks. Behavioral data confirm specific bias toward a reward-relevant modality. Increased reward expectation improves reaction time and accuracy in the relevant dimension while reducing sensitivity to modulations of stimuli characteristics in the irrelevant dimension. Analysis of functional magnetic resonance imaging data shows that the proximity to reward over successive trials is associated with increased activity of the medial frontal cortex regardless of the modality. However, there are modality-specific changes in brain activity in the lateral frontal, parietal, and temporal cortex. Analysis of effective connectivity suggests that reward expectancy enhances coupling in both early visual pathways and within the prefrontal cortex. These distributed changes in task-related cortical networks arise from subjects' representations of future events and likelihood of reward.
Unconscious perception is commonly described as a phenomenon that is not under intentional control and relies on automatic processes. We challenge this view by arguing that some automatic processes ...may indeed be under intentional control, which is implemented in task-sets that define how the task is to be performed. In consequence, those prime attributes that are relevant to the task will be most effective. To investigate this hypothesis, we used a paradigm which has been shown to yield reliable short-lived priming in tasks based on semantic classification of words. This type of study uses fast, well practised classification responses, whereby responses to targets are much less accurate if prime and target belong to a different category than if they belong to the same category. In three experiments, we investigated whether the intention to classify the same words with respect to different semantic categories had a differential effect on priming. The results suggest that this was indeed the case: Priming varied with the task in all experiments. However, although participants reported not seeing the primes, they were able to classify the primes better than chance using the classification task they had used before with the targets. When a lexical task was used for discrimination in experiment 4, masked primes could however not be discriminated. Also, priming was as pronounced when the primes were visible as when they were invisible. The pattern of results suggests that participants had intentional control on prime processing, even if they reported not seeing the primes.
There are now a number of experimental studies showing that modification of interpretation biases can influence later emotional vulnerability. We present a series of three experiments in which the ...first two studies showed no such effects, apparently due to the content of training differing in certain critical respects from that of the intended target for modification: namely, coping with the experience of failure. When content of training and emotional stressor tasks were matched in Experiment Three the expected effects of bias modification on stress reactivity was evident. In other words, over the three experiments, negative emotional response due to failure in an apparently easy (but actually difficult) cognitive test was modified as expected only when training involved both content related to achievement threat and benign appraisals for failure. These results demonstrate the importance of matching the content of training to the intended target for change and have implications for transferring cognitive bias modification methods from the laboratory to clinical settings.
Reaction times for categorization of a probe face according to its sex or fame were contrasted as a function of whether the category of a preceding, sandwich-masked prime face was congruent or ...incongruent. Prime awareness was measured by the ability to later categorize the primes, and this was close to chance and typically uncorrelated with priming. When prime faces were never presented as visible probes within a test, priming was not reliable; when prime faces were also seen as probes, priming was only reliable if visible and masked presentation of faces were interleaved (not simply if primes had been visible in a previous session). In the latter case, priming was independent of experimentally induced face-response or face-category contingencies, ruling out any simple form of stimulus-response learning. We conclude that the reliable masked congruency priming reflects bindings between stimuli and multiple, abstract classifications that can be generated both overtly and covertly.
Memory formation is commonly thought to rely on brain activity following an event. Yet, recent research has shown that even brain activity previous to an event can predict later recollection ...(subsequent memory effect, SME). In order to investigate the attentional sources of the SME, event‐related potentials (ERPs) elicited by task cues preceding target words were recorded in a switched task paradigm that was followed by a surprise recognition test. Stay trials, that is, those with the same task as the previous trial, were contrasted with switch trials, which included a task switch compared to the previous trial. The underlying assumption was that sustained attention would be dominant in stay trials and that transient attentional reconfiguration processes would be dominant in switch trials. To determine the SME, local and global statistics of scalp electric fields were used to identify differences between subsequently remembered and forgotten items. Results showed that the SME in stay trials occurred in a time window from 2 to 1 sec before target onset, whereas the SME in switch trials occurred subsequently, in a time window from 1 to 0 sec before target onset. Both SMEs showed a frontal negativity resembling the topography of previously reported effects, which suggests that sustained and transient attentional processes contribute to the prestimulus SME in consecutive time periods.
Investigating preparatory processes that enable predicting later recollection we analyzed the event‐related potentials (ERPs) difference between subsequently remembered and forgotten items defined as prestimulus subsequent memory effect (SME). To clarify the nature and the time course of these preparatory processes we considered the contribution of sustained and transient attentional mechanisms involved in two different learning conditions: one characterized by the repetition of the same task across two or more consecutive trials (stay trials) and the other characterized by switching between different task sets (switch trials). We found an SME for stay trials in a time window from 2 to 1 sec before target onset, followed by SME for switch trials in a time window from 1 to 0 sec before target onset. These findings suggest that sustained and transient attentional processes contribute to the prestimulus SME in consecutive time periods.
The aim of this study was to investigate unconscious priming by the use of a spatial mirror-masking paradigm. Words and nonwords with no under-length letters are mirrored at their horizontal axis. ...The results are figures of geometric-like forms that contain letters in their upper part. In the three experiments reported in this study, a priming procedure used such mirrored words and nonwords as primes. Participants were ignorant of the nature of the construction of the stimuli. Perceptual reports of the participants revealed that they did not realize that words were hidden in the primes. Nevertheless, they showed priming in all three experiments. Priming effects were replicated with prime–target SOAs of between 1 and 3
s. Functional dissociations were found between ignorant and informed participants. Informed groups showed perceptual and semantic priming, while ignorant groups showed only perceptual priming.
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