Motor planning and execution in left- and right-handed individuals during a bimanual grasping and placing task

The issue of handedness has been the topic of great interest for researchers in a number of scientific domains. It is typically observed that the dominant hand yields numerous behavioral advantages over the non-dominant hand during unimanual tasks, which provides evidence of hemispheric specialization. In contrast to advantages for the dominant hand during motor execution, recent research has demonstrated that the right hand has advantages during motor planning (regardless of handedness), indicating that motor planning is a specialized function of the left hemisphere. In the present study we explored hemispheric advantages in motor planning and execution in left- and right-handed individuals during a bimanual grasping and placing task. Replicating previous findings, both motor planning and execution was influenced by object end-orientation congruency. In addition, although motor planning (i.e., end-state comfort) was not influenced by hand or handedness, motor execution differed between left and right hand, with shorter object transport times observed for the left hand, regardless of handedness. These results demonstrate that the hemispheric advantages often observed in unimanual tasks do not extend to discrete bimanual tasks. We propose that the differences in object transport time between the two hands arise from overt shifting visual fixation between the two hands/objects.     

Number versus continuous quantity in numerosity judgments by fish

A fundamental question in human cognition is how people reason about space. We use a computational model to explore cross-cultural commonalities and differences in spatial cognition. Our model is based upon two hypotheses: (1) the structure-mapping model of analogy can explain the visual comparisons used in spatial reasoning; and (2) qualitative, structural representations are computed by people’s visual systems and used in these comparisons. We apply our model to a visual oddity task, in which individuals are shown an array of two-dimensional images and asked to the pick the one that does not belong. This task was previously used to evaluate understanding of geometric concepts in two disparate populations: North Americans, and the Mundurukú, a South American indigenous group. Our model automatically generates representations of each hand-segmented image and compares them to solve the task. The model achieves human-level performance on this task, and problems that are hard for the model are also difficult for people in both cultures. Furthermore, ablation studies on the model suggest explanations for cross-cultural differences in terms of differences in spatial representations.     

Plasticity of human spatial cognition: spatial language and cognition covary across cultures

The present paper explores cross-cultural variation in spatial cognition by comparing spatial reconstruction tasks by Dutch and Namibian elementary school children. These two communities differ in the way they predominantly express spatial relations in language. Four experiments investigate cognitive strategy preferences across different levels of task-complexity and instruction. Data show a correlation between dominant linguistic spatial frames of reference and performance patterns in non-linguistic spatial memory tasks. This correlation is shown to be stable across an increase of complexity in the spatial array. When instructed to use their respective non-habitual cognitive strategy, participants were not easily able to switch between strategies and their attempts to do so impaired their performance. These results indicate a difference not only in preference but also in competence and suggest that spatial language and non-linguistic preferences and competences in spatial cognition are systematically aligned across human populations.     

Ethnic Minority‐Majority Asymmetry in National Attitudes around the World: A Multilevel Analysis

Using data from the International Social Survey Programme, this research investigated asymmetric attitudes of ethnic minorities and majorities towards their country and explored the impact of human development, ethnic diversity, and social inequality as country‐level moderators of national attitudes. In line with the general hypothesis of ethnic asymmetry, we found that ethnic, linguistic, and religious majorities were more identified with the nation and more strongly endorsed nationalist ideology than minorities (H1, 33 countries). Multilevel analyses revealed that this pattern of asymmetry was moderated by country‐level characteristics: the difference between minorities and majorities was greatest in ethnically diverse countries and in egalitarian, low inequality contexts. We also observed a larger positive correlation between ethnic subgroup identification and both national identification and nationalism for majorities than for minorities (H2, 20 countries). A stronger overall relationship between ethnic and national identification was observed in countries with a low level of human development. The greatest minority‐majority differences in the relationship between ethnic identification and national attitudes were found in egalitarian countries with a strong welfare state tradition.     

Der Begriff der „Bekundung“ bei Husserl und Heidegger

The article intends to explore the extension of several Husserlian concepts and issues in Heidegger’s first lectures of the 1920s. To this extent it focuses especially on the concept of Bekundung (intimation), exposed by Husserl in the second book of his Ideas, and also discussed by Heidegger in his Freiburg lecture Grundprobleme der Phänomenologie (WS 1919/20). By following this concept both in Husserl’s theory of the constitution of materiality and causal reality, as well as in his discussion of the personal self, and by pointing out the tensions between the two perspectives, we will try to show that Heidegger’s use of the term can in several aspects be seen as an attempt to solve certain difficulties of the Husserlian perspective. Thus, we wish to sketch out a part of that complex network of continuities and differences that constitute the “common ground” of the two thinkers in the early 1920s.     

Strategic adaptation to performance objectives in a dual-task setting

How do people interleave attention when multitasking? One dominant account is that the completion of a subtask serves as a cue to switch tasks. But what happens if switching solely at subtask boundaries led to poor performance? We report a study in which participants manually dialed a UK‐style telephone number while driving a simulated vehicle. If the driver were to exclusively return his or her attention to driving after completing a subtask (i.e., using the single break in the xxxxx‐xxxxxx representational structure of the number), then we would expect to see a relatively poor driving performance. In contrast, our results show that drivers choose to return attention to steering control before the natural subtask boundary. A computational modeling analysis shows that drivers had to adopt this strategy to meet the required performance objective of maintaining an acceptable lateral position in the road while dialing. Taken together these results support the idea that people can strategically control the allocation of attention in multitask settings to meet specific performance criteria.     

High regularities in eye-movement patterns reveal the dynamics of the visual working memory allocation mechanism

With only two to five slots of visual working memory (VWM), humans are able to quickly solve complex visual problems to near optimal solutions. To explain the paradox between tightly constrained VWM and impressively complex human visual problem-solving ability, we propose several principles for dynamic VWM allocation. In particular, we propose that complex visual information is represented in a temporal manner using only a few slots of VWM that include global and local visual chunks. We built a model of human traveling salesman problem solving based on these principles of VWM allocation and tested the model with eye-movement data. Exactly as the model predicted, human eye movements during traveling salesman problem solving have precise quantitative regularities with regard to both the general statistical pattern of attentional fixations and how they vary across individuals with different VWM capacities. Even though VWM capacity is very limited, eye movements dynamically allocate VWM resources to both local and global information, enabling attention to fine details without loss of the big picture.     

Evidenzbasierte Psychotherapie der Depression

Depressive disorders are among the most frequent reasons for utilizing the health care system. Despite the availability of efficacious treatments and further advances throughout the last years, there is still a need for improving diagnostic and therapeutic procedures. A promising approach is the implementation of evidence- and consensus-based guidelines. The German “Nationale VersorgungsLeitlinie Unipolare Depression” are evidence- and consensus-based clinical practise guidelines for patients with unipolar depression. All relevant stakeholders have been involved in its development and have passed the final version at the end of 2009 to foster compliance throughout. The available evidence allows the derivation of differentiated treatment recommendations, also with regard to concomitant antidepressant medication or as alternative treatment options. In acute therapy watchful waiting over 14 days is recommended for mild depression and psychotherapy after persistence of symptoms. In cases of moderate depression, psychotherapy and pharmacotherapy are equally recommended, in cases of severe depression a combination of both is recommended.     

Exploratory Health Disparities Research: The Need to Provide a Tangible Benefit to Vulnerable Respondents

This article examines the responsibilities of researchers who conduct exploratory research to provide a service to vulnerable respondents. The term "service" is used to denote the provision of a tangible benefit in relation to the research question that is apart from the altruistic research benefits. This article explores what this "service" could look like, who might be responsible for providing it, and the challenges associated with such a service. The article argues that not providing a tangible benefit to vulnerable research participants is inconsistent with the principle of social justice that undergirds much of the rationale for conducting health disparities research.