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Six experiments examined the proposal that an item of long-term knowledge can be simultaneously inhibited and activated. In 2 directed forgetting experiments items to-be-forgotten were found to be inhibited in list-cued recall but activated in lexical decision tasks. In 3 retrieval practice experiments, unpracticed items from practiced categories were found to be inhibited in category-cued recall but were primed in lexical decision. If, however, the primes and targets in lexical decision were taken directly from the study list, inhibition was observed. Finally, it was found that when items highly associated with a study list were processed in between study and test, no inhibition in recall was present. These, and a broad range of other findings, can be explained by the concept of "episodic inhibition," which proposes that episodic memories retain copies of semantic knowledge structures that preserve patterns of activation/inhibition originally generated in those structures during encoding. ((c) 2006 APA, all rights reserved).

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A verbális munkamemória feladata a „beszédszerű”információk átmeneti tárolása és frissítése, kapacitásában jelentős egyéni különbségek figyelhetőek meg, amelyek egy sor kognitív funkció működését modulálják. A verbális munkamemória kapacitásának felmérésére számos diagnosztikai eszköz vált széles körben alkalmazottá, de ezek magyar nyelvű változatai eddig csak szórványos kísérleti vizsgálatokban láttak napvilágot. A verbális munkamemória-tárolási és -frissítési komponensei rendkívüli módon érzékenyek az adott információ hosszúságára, kimondási idejére, fonológiai szerveződésére, így az elsősorban angol nyelvű eszközök mutatói csak korlátozottan voltak használhatóak a magyar nyelvű vizsgálatok számára. Kutatócsoportunk ezt a hiányt pótolta, amikor elkészítette a három legismertebb verbális munkamemória-feladat: a számterjedelmi teszt, az álszóteszt és az olvasásterjedelmi teszt magyar nyelvű változatait. Ebben a tanulmányban a feladatsorokkal együtt közreadjuk a feladatokkal kapcsolatos normatív adatokat is.

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The testing effect refers to the phenomenon that repeated retrieval of memories promotes better long-term retention than repeated study. To investigate the neural correlates of the testing effect, we used event-related functional magnetic resonance imaging methods while participants performed a cued recall task. Prior to the neuroimaging experiment, participants learned Swahili-German word pairs, then half of the word pairs were repeatedly studied, whereas the other half were repeatedly tested. For half of the participants, the neuroimaging experiment was performed immediately after the learning phase; a 1-week retention interval was inserted for the other half of the participants. We found that a large network of areas identified in a separate 2-back functional localizer scan were active during the final recall of the word pair associations. Importantly, the learning strategy (retest or restudy) of the word pairs determined the manner in which the retention interval affected the activations within this network. Recall of previously restudied memories was accompanied by reduced activation within this network at long retention intervals, but no reduction was observed for previously retested memories. We suggest that retrieval promotes learning via stabilizing cue-related activation patterns in a network of areas usually associated with cognitive and attentional control functions.

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A constant task for every living organism is to decide whether to exploit rewards associated with current behavior or to explore the environment for more rewarding options. Current empirical evidence indicates that exploitation is related to phasic whereas exploration is related to tonic firing mode of noradrenergic neurons in the locus coeruleus. In humans, this exploration-exploitation trade-off is subserved by the ability to flexibly switch attention between task-related and task-irrelevant information. Here, we investigated whether this function, called attentional set shifting, is related to exploration and tonic noradrenergic discharge. We measured pretrial baseline pupil dilation, proved to be strongly correlated with the activity of the locus coeruleus, while human participants took part in well-known tasks of attentional set shifting. Study 1 used the Wisconsin Card Sorting Task, whereas in Study 2, the Intra/Extradimensional Set Shifting Task was used. Both tasks require participants to choose between different compound stimuli based on feedback provided for their previous decisions. During the task, stimulus-reward contingencies change periodically, thus participants are repeatedly required to reassess which stimulus features are relevant (i.e., they shift their attentional set). Our results showed that baseline pupil diameter steadily decreased when the stimulus-reward contingencies were stable, whereas they suddenly increased when these contingencies changed. Analysis of looking patterns also confirmed the presence of exploratory behavior during attentional set shifting. Thus, our results suggest that tonic firing mode of noradrenergic neurons in the locus coeruleus is implicated in attentional set shifting, as it regulates the amount of exploration.