Psychological Research

Colzato, Lorenza; de Haan, Annelies; Hommel, Bernhard

doi: 10.1007/s00426-014-0610-4pmid: 25257259

Anecdotal evidence suggests that creative people sometimes use food to overcome mental blocks and lack of inspiration, but empirical support for this possibility is still lacking. In this study, we investigated whether creativity in convergent- and divergent-thinking tasks is promoted by the food supplement l-Tyrosine (TYR)—a biochemical precursor of dopamine, which is assumed to drive cognitive control and creativity. We found no evidence for an impact of TYR on divergent thinking (“brainstorming”) but it did promote convergent (“deep”) thinking. As convergent thinking arguably requires more cognitive top-down control, this finding suggests that TYR can facilitate control-hungry creative operations. Hence, the food we eat may affect the way we think.

Pindus, Dominika; Davis, Robert; Hillman, Charles; Bandelow, Stephan; Hogervorst, Eef; Biddle, Stuart; Sherar, Lauren

doi: 10.1007/s00426-014-0612-2pmid: 25351943

The aim of this study was to assess the relations of daily moderate-to-vigorous physical activity (MVPA) to cognitive functions in 15-year-old adolescents from the Avon Longitudinal Study of Parents and Children while controlling for aerobic fitness. A sub-sample of 667 adolescents (M age = 15.4 ± 0.16 years; 55 % females) who provided valid data on variables of interest, were used in the analyses. MVPA was objectively assessed using an Actigraph GT1M accelerometer and aerobic fitness was expressed as physical work capacity at the heart rate of 170 beats per minute from a cycle ergometer test. A computerized stop-signal task was used to measure mean reaction time (RT) and standard deviation of RT, as indicators of cognitive processing speed and variability during an attention and inhibitory control task. MVPA was not significantly related to cognitive processing speed or variability of cognitive performance in hierarchical linear regression models. In simple regression models, aerobic fitness was negatively related to mean RT on the simple go condition. Our results suggest that aerobic fitness, but not MVPA, was associated with cognitive processing speed under less cognitively demanding task conditions. The results thus indicate a potential global effect of aerobic fitness on cognitive functions in adolescents but this may differ depending on the specific task characteristics.

Nakashima, Ryoichi; Watanabe, Chisaki; Maeda, Eriko; Yoshikawa, Takeharu; Matsuda, Izuru; Miki, Soichiro; Yokosawa, Kazuhiko

doi: 10.1007/s00426-014-0616-ypmid: 25269540

How does domain-specific knowledge influence the experts’ performance in their domain of expertise? Specifically, can visual search experts find, with uniform efficiency, any type of target in their domain of expertise? We examined whether acquired knowledge of target importance influences an expert’s visual search performance. In some professional searches (e.g., medical screenings), certain targets are rare; one aim of this study was to examine the extent to which experts miss such targets in their searches. In one experiment, radiologists (medical experts) engaged in a medical lesion search task in which both the importance (i.e., seriousness/gravity) and the prevalence of targets varied. Results showed decreased target detection rates in the low prevalence conditions (i.e., the prevalence effect). Also, experts were better at detecting important (versus unimportant) lesions. Results of an experiment using novices ruled out the possibility that decreased performance with unimportant targets was due to low target noticeability/visibility. Overall, the findings suggest that radiologists do not have a generalized ability to detect any type of lesion; instead, they have acquired a specialized ability to detect only those important lesions relevant for effective medical practices.

Coburn, Patricia; Bernstein, Daniel; Begeer, Sander

doi: 10.1007/s00426-014-0606-0pmid: 25183385

Theory of mind (ToM) is the ability to take other people’s perspective by inferring their mental state. Most 6-year olds pass the change-of-location false belief task that is commonly used to assess ToM. However, the change-of-location task is not suitable for individuals over 5 years of age, due to its discrete response options. In two experiments, we used a paper and pencil version of a modified change-of-location task (the Real Object Sandbox task) to assess false belief reasoning continuously rather than discretely in adults. Participants heard nine change-of-location scenarios and answered a critical question after each. The memory control questions only required the participant to remember the object’s original location, whereas the false belief questions required participants to take the perspective of the protagonist. Participants were more accurate on memory trials than trials requiring perspective taking, and performance on paper and pencil trials correlated with corresponding trials on the Real Object Sandbox task. The Paper and Pencil Sandbox task is a convenient continuous measure of ToM that could be administered to a wide range of age groups.

Seli, Paul; Carriere, Jonathan; Smilek, Daniel

doi: 10.1007/s00426-014-0617-xpmid: 25284016

In two large samples we show a dissociation between trait-level tendencies to mind-wander spontaneously (unintentionally) and deliberately (intentionally). Participants completed online versions of the Mind Wandering Spontaneous (MW-S) and the Mind Wandering Deliberate (MW-D) self-report scales and the Five Facet Mindfulness Questionnaire (FFMQ). The results revealed that deliberate and spontaneous mind wandering were uniquely associated with some factors of the FFMQ. Notably, while the MW-D and the MW-S were positively associated with each other, the MW-D was uniquely positively associated with the ‘Non-Reactivity to Inner Experience’ factor of the FFMQ, whereas the MW-S was uniquely negatively associated with this factor. We also showed that conflating deliberate and spontaneous mind wandering can result in a misunderstanding of how mind wandering is related to other traits. We recommend that studies assessing individual differences in mind wandering should distinguish between deliberate and spontaneous subtypes of mind wandering to avoid possibly erroneous conclusions.

Schuch, Stefanie; Koch, Iring

doi: 10.1007/s00426-014-0602-4pmid: 25100233

Conflict adaptation can be measured by the “congruency sequence effect”, denoting the reduction of congruency effects after incongruent trials (where response conflict occurs) relative to congruent trials (without response conflict). Recently, it has been reported that conflict adaptation is larger in negative mood than in positive mood (van Steenbergen et al., Psychological Science 21:1629–1634, 2010). We conducted two experiments further investigating this important finding. Two different interference paradigms were applied to measure conflict adaptation: Experiment 1 was a Flanker task, Experiment 2 was a Stroop-like task. To get as pure a measure of conflict adaptation as possible, we minimized the influence of trial-to-trial priming effects by excluding all kinds of stimulus repetitions. Mood states were induced by presenting film clips with emotional content prior to the interference task. Three mood states were manipulated between subjects: amused, anxious, and sad. Across both interference paradigms, we consistently found conflict adaptation in negative, but not in positive mood. Taken together with van Steenbergen et al. (Psychological Science 21:1629–1634, 2010) findings, the results suggest that the negative-mood-triggered increase in conflict adaptation is a general phenomenon that occurs independently of the particular mood-induction procedure and interference paradigm involved.

Megías, Patricia; Macizo, Pedro; Herrera, Amparo

doi: 10.1007/s00426-014-0603-3pmid: 25078883

In two experiments we evaluated the coactivation of arithmetic facts and the possible inhibitory mechanism used to select the correct one. To this end, we introduced an adapted version of the negative priming paradigm in which participants received additions and they decided whether they were correct or not. When the addition was incorrect but the result was that of multiplying the operands (e.g., 2 + 4 = 8), participants took more time to respond relative to control additions with unrelated results. This finding corroborated that participants coactivated arithmetic facts of multiplications even when they were irrelevant to perform the task. Moreover, the participants were slower to respond to an addition whose result was that of multiplying the operands of the previous trial (e.g., 2 + 6 = 8). These results support the existence of an inhibitory mechanism involved in the selection of arithmetic facts.

Montefinese, Maria; Zannino, Gian; Ambrosini, Ettore

doi: 10.1007/s00426-014-0615-zpmid: 25267547

In everyday life, human beings can report memories of past events that did not occur or that occurred differently from the way they remember them because memory is an imperfect process of reconstruction and is prone to distortion and errors. In this recognition study using word stimuli, we investigated whether a specific operationalization of semantic similarity among concepts can modulate false memories while controlling for the possible effect of associative strength and word co-occurrence in an old–new recognition task. The semantic similarity value of each new concept was calculated as the mean cosine similarity between pairs of vectors representing that new concept and each old concept belonging to the same semantic category. Results showed that, compared with (new) low-similarity concepts, (new) high-similarity concepts had significantly higher probability of being falsely recognized as old, even after partialling out the effect of confounding variables, including associative relatedness and lexical co-occurrence. This finding supports the feature-based view of semantic memory, suggesting that meaning overlap and sharing of semantic features (which are greater when more similar semantic concepts are being processed) have an influence on recognition performance, resulting in more false alarms for new high-similarity concepts. We propose that the associative strength and word co-occurrence among concepts are not sufficient to explain illusory memories but is important to take into account also the effects of feature-based semantic relations, and, in particular, the semantic similarity among concepts.

Tempel, Tobias; Frings, Christian

doi: 10.1007/s00426-014-0604-2pmid: 25158830

We investigated the dependence of retrieval-induced forgetting of verbal material from influences of word representations in semantic memory. Participants learned novel words, that is, letter strings that were non-words. These items were grouped into different artificial categories during learning. Subsequently, participants retrieval-practiced subsets of items from a part of the categories. This selective retrieval enhanced the recall of practiced items in a final memory test, but impaired memory for non-retrieved items belonging to the same categories. Retrieval-induced forgetting occurred with regard to the number of recalled items, as well as with regard to response times. The results show that episodic associations suffice for selective retrieval of verbal material to entail retrieval-induced forgetting independent of association strength between items and categories in semantic memory. The relevance of this finding for the postulate of interference dependence within the inhibitory account of retrieval-induced forgetting is discussed.

Güldenpenning, Iris; Braun, Jelena; Machlitt, Daniel; Schack, Thomas

doi: 10.1007/s00426-014-0607-zpmid: 25187216

Fast motor actions in sports often require the ability to discriminate between similar movement patterns (e.g. feint vs. non-feint) at an early stage. Moreover, an athlete might even initiate a motor response without a conscious processing of the relevant movement information. Therefore, the question was raised of whether or not athletes and novices of a particular movement can unconsciously distinguish between similar movement patterns. Using a masked priming experiment (Experiment 1), it is demonstrated that both groups were similarly able to unconsciously distinguish a feint and a non-feint action. To further investigate whether this result is based on perceptual priming effects or on unconscious motor activations, a second masked priming experiment was conducted (Experiment 2). Experiment 2 revealed perceptual priming effects which are not mediated by motor expertise. Moreover, unconscious pictures of feint and non-feint actions from different movement stages are sufficient to activate a motor response in athletes. In novices, a negative congruency effect occurred. For both groups, largest response congruency effects were found for prime pictures participants could consciously perceive as target pictures during the experimental session. The results found here point out that perceptual priming effects are not mediated by motor expertise whereas response priming effects might be.