Differences between Spatial and Visual Mental Representations

This article investigates the relationship between visual mental representations and spatial mental representations in human visuo-spatial processing. By comparing two common theories of visuo-spatial processing – mental model theory and the theory of mental imagery – we identified two open questions: (1) which representations are modality-specific, and (2) what is the role of the two representations in reasoning. Two experiments examining eye movements and preferences for under-specified problems were conducted to investigate these questions. We found that significant spontaneous eye movements along the processed spatial relations occurred only when a visual mental representation is employed, but not with a spatial mental representation. Furthermore, the preferences for the answers of the under-specified problems differed between the two mental representations. The results challenge assumptions made by mental model theory and the theory of mental imagery

The Role of the Center-of-Mass in Evaluating Spatial Language

Kluth T, Burigo M, Schultheis H, Knoeferle P. The Role of the Center-of-Mass in Evaluating Spatial Language. In: Barkowsky T, Falomir Llansola Z, Schultheis H, van de Ven J, eds. KogWis 2016. Space for Cognition. 13th Biannual Conference of the German Cognitive Science Society: Proceedings. Bremen: Universität Bremen; 2016: 11-14

Attentional distribution and spatial language

Kluth T, Schultheis H. Attentional distribution and spatial language. In: Freksa C, Nebel B, Hegarty M, Barkowsky T, eds. Spatial Cognition IX. Lecture Notes in Computer Science. Vol 8684. Springer International Publishing; 2014: 76-91.Whether visual spatial attention can be split to several discontinuous locations concurrently is still an open and intensely debated question. We address this question in the domain of spatial language use by comparing two existing and three newly proposed computational models. All models are assessed regarding their ability to account for human acceptability ratings for how well a given spatial term describes the spatial arrangement of two functionally related objects. One of the existing models assumes that taking the functional relations into account involves split attention. All new models incorporate functional relations without assuming split attention. Our simulations suggest that not assuming split attention is more appropriate for taking the functional relations into account than assuming split attention. At the same time, the simulations raise doubt as to whether any of the models appropriately captures the impact of functional relations on spatial language use

Rating Distributions and Bayesian Inference. Enhancing Cognitive Models of Spatial Language Use

Kluth T, Schultheis H. Rating Distributions and Bayesian Inference. Enhancing Cognitive Models of Spatial Language Use. In: Idiart M, Lenci A, Poibeau T, Villavicencio A, eds. Proceedings of the Eighth Workshop on Cognitive Aspects of Computational Language Learning and Processing. Melbourne, Australia: Association for Computational Linguistics; 2018: 47-55.We present two methods that improve the assessment of cognitive models. The first method is applicable to models computing average acceptability ratings. For these models, we propose an extension that simulates a full rating distribution (instead of average ratings) and allows generating individual ratings. Our second method enables Bayesian inference for models generating individual data. To this end, we propose to use the cross-match test (Rosenbaum, 2005) as a likelihood function. We exemplarily present both methods using cognitive models from the domain of spatial language use. For spatial language use, determining linguistic acceptability judgments of a spatial preposition for a depicted spatial relation is assumed to be a crucial process (Logan and Sadler, 1996). Existing models of this process compute an average acceptability rating. We extend the models and – based on existing data – show that the extended models allow extracting more information from the empirical data and yield more readily interpretable information about model successes and failures. Applying Bayesian inference, we find that model performance relies less on mechanisms of capturing geometrical aspects than on mapping the captured geometry to a rating interval

Distinguishing Cognitive Models of Spatial Language Understanding

Kluth T, Burigo M, Schultheis H, Knoeferle P. Distinguishing Cognitive Models of Spatial Language Understanding. In: Reitter D, Ritter FE, eds. Proceedings of the 14th International Conference on Cognitive Modeling (ICCM 2016). University Park, Pennsylvania, USA: Penn State; 2016: 230-231

In-depth transcriptomic analysis of human retina reveals molecular mechanisms underlying diabetic retinopathy

Diabetic Retinopathy (DR) is among the major global causes for vision loss. With the rise in diabetes prevalence, an increase in DR incidence is expected. Current understanding of both the molecular etiology and pathways involved in the initiation and progression of DR is limited. Via RNA-Sequencing, we analyzed mRNA and miRNA expression profiles of 80 human post-mortem retinal samples from 43 patients diagnosed with various stages of DR. We found differentially expressed transcripts to be predominantly associated with late stage DR and pathways such as hippo and gap junction signaling. A multivariate regression model identified transcripts with progressive changes throughout disease stages, which in turn displayed significant overlap with sphingolipid and cGMP-PKG signaling. Combined analysis of miRNA and mRNA expression further uncovered disease-relevant miRNA/mRNA associations as potential mechanisms of post-transcriptional regulation. Finally, integrating human retinal single cell RNA-Sequencing data revealed a continuous loss of retinal ganglion cells, and Müller cell mediated changes in histidine and β-alanine signaling. While previously considered primarily a vascular disease, attention in DR has shifted to additional mechanisms and cell-types. Our findings offer an unprecedented and unbiased insight into molecular pathways and cell-specific changes in the development of DR, and provide potential avenues for future therapeutic intervention

Size Matters. Effects of Relative Distance on the Acceptability of Spatial Prepositions

Kluth T, Burigo M, Schultheis H, Knoeferle P. Size Matters. Effects of Relative Distance on the Acceptability of Spatial Prepositions. In: Shestakova A, Moiseeva V, Myachykov A, et al., eds. The 10th Annual Embodied and Situated Language Processing. Moscow, Russia: Centre for Cognition and Decision Making, Higher School of Economics; 2017: 26

Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p<0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (<1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (<1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

A psychoacoustic auditory display for navigation

A psychoacoustic auditory display for navigation in two-dimensional space is presented. The auditory display is examined in an experiment with novice users. Trajectory analysis indicates that users were able to a) accurately find sonified targets b) analyze the sonification axis-by-axis c) integrate the sonified dimensions to approach the target on the shortest path. Techniques developed in this work appear to work equally well with three-dimensional coordinates