More than 300 years ago, the philosopher René Descartes asked a disturbing question: If our senses can’t always be trusted, how can we separate illusion from reality? We’re able to do so, a new study suggests, because our brain keeps tabs on reality by constantly questioning its own past expectations and beliefs. Hallucinations occur when this internal fact-checking fails, a finding that could point toward better treatments for schizophrenia and other psychiatric disorders.

Source: www.sciencemag.org

Understanding how humans sustain cooperation in large, anonymous societies remains a central question of both theoretical and practical importance. In the laboratory, experimental behavioural research using tools like public goods games suggests that cooperation can be sustained by institutional punishment—analogous to governments, police forces and other institutions that sanction free-riders on behalf of individuals in large societies1,2,3. In the real world, however, corruption can undermine the effectiveness of these institutions4,5,6,7,8. Levels of corruption correlate with institutional, economic and cultural factors, but the causal directions of these relationships are difficult to determine5,6,8,​9,​10. Here, we experimentally model corruption by introducing the possibility of bribery. We investigate the effect of structural factors (a leader’s punitive power and economic potential), anti-corruption strategies (transparency and leader investment in the public good) and cultural background. The results reveal that (1) corruption possibilities cause a large (25%) decrease in public good provisioning, (2) empowering leaders decreases cooperative contributions (in direct opposition to typical institutional punishment results), (3) growing up in a more corrupt society predicts more acceptance of bribes and (4) anti-corruption strategies are effective under some conditions, but can further decrease public good provisioning when leaders are weak and the economic potential is poor. These results suggest that a more nuanced approach to corruption is needed and that proposed panaceas, such as transparency, may actually be harmful in some contexts.

Corrupting cooperation and how anti-corruption strategies may backfire
Michael Muthukrishna, Patrick Francois, Shayan Pourahmadi & Joseph Henrich
Nature Human Behaviour 1, Article number: 0138 (2017)
doi:10.1038/s41562-017-0138

Source: www.nature.com

Functional connectivity (FC) analysis has revealed stable and reproducible features of brain network organization, as well as their variations across individuals. Here, we localize network markers of individual variability in FC and track their dynamical expression across time. First, we determine the minimal set of network components required to identify individual subjects. Among specific resting-state networks, we find that the FC pattern of the frontoparietal network allows for the most reliable identification of individuals. Looking across the whole brain, an optimization approach designed to identify a minimal node set converges on distributed portions of the frontoparietal system. Second, we track the expression of these network markers across time. We find that the FC fingerprint is most clearly expressed at times when FC patterns exhibit low modularity. In summary, our study reveals distributed network markers of individual variability that are localized in both space and time.

Spatiotemporal Network Markers of Individual Variability in the Human Functional Connectome
Cleofé Peña-Gómez Andrea Avena-Koenigsberger Jorge Sepulcre Olaf Sporns
Cerebral Cortex, https://doi.org/10.1093/cercor/bhx170

Source: academic.oup.com

Newly available data on the spatial distribution of retail activities in cities makes it possible to build models formalized at the level of the single retailer. Current models tackle consumer location choices at an aggregate level and the opportunity new data offers for modeling at the retail unit level lacks an appropriate theoretical framework. The model we present here helps to address these issues. Based on random utility theory, we have built it around the idea of quantifying the role of floor-space and agglomeration in retail location choice. We test this model on the inner area of Greater London. The results are consistent with a super linear scaling of a retailer’s attractiveness with its floorspace, and with an agglomeration effect approximated as the total retail floorspace within a 300 m radius from each shop. Our model illustrates many of the issues involved in testing and validating urban simulation models involving spatial data and its aggregation to different spatial scales.

Quantifying Retail Agglomeration using Diverse Spatial Data
Duccio Piovani, Vassilis Zachariadis & Michael Batty
Scientific Reports 7, Article number: 5451 (2017)
doi:10.1038/s41598-017-05304-1

Source: www.nature.com