Removing financial incentives demotivates the brain

Social scientists and many biologists are all preoccupied in different ways with the nature and effects of the ways incentives influence behavior. One type of incentive is clearly intrinsic; it originates within a person and is often linked to exploratory behavior, hedonic pleasure from self-determined mastery, and desire to satisfy curiosity for its own sake (1). Another type of incentive is extrinsic; typically, it is designed and administered by an outside person or authority, is precise, and is usually financial, tied to fame, or has some other kind of monetizable status. Because of its various natures, intrinsic motivation is difficult to measure and observe. An adventurous step is to measure brain activity during conditions of apparent intrinsic and extrinsic motivation. Murayama et al. (2) do exactly this. Their results are striking evidence for a phenomenon often noted in social psychology—namely, extrinsic incentives (e.g., pay) can undermine intrinsic incentives (e.g., fun)

Aesthetics and morality judgments share cortical neuroarchitecture

Philosophers have predominantly regarded morality and aesthetics judgments as fundamentally different. However, whether this claim is empirically founded has remained unclear. In a novel task, we measured brain activity of participants judging the aesthetic beauty of artwork or the moral goodness of actions depicted. To control for the content of judgments, participants assessed the age of the artworks and the speed of depicted actions. Univariate analyses revealed whole-brain corrected, content-controlled common activation for aesthetics and morality judgments in frontopolar, dorsomedial and ventrolateral prefrontal cortex. Temporoparietal cortex showed activation specific for morality judgments, occipital cortex for aesthetics judgments. Multivariate analyses revealed both common and distinct whole-brain corrected representations for morality and aesthetics judgments in temporoparietal and prefrontal regions. Overall, neural commonalities are more pronounced than predominant philosophical views would predict. They are compatible with minority accounts that stress commonalities between aesthetics and morality judgments, such as sentimentalism and a valuation framework

Impacts of Personality on Herding in Financial Decision-Making

It is well known that rational bubbles can be sustained in balanced growth path of a deterministic economy when the return to capital r is equal to the growth rate g. When there is a lack of stores of value, bubbles can implement an efficient allocation. This paper considers a world where r fluctuates over time due to shocks to the marginal productivity of capital. Then, bubbles further efficiency, though they cannot implement first best. While bubbles can only be sustained when r = g in a deterministic economy, r > g "on average" in a stochastic economy. Fiscal policy improves welfare by adding an extra asset. Where only the elderly contribute to shifting resources between investment and consumption in a bubbly economy, fiscal policy allows part of that burden to be shifted to the young. Contrary to common wisdom, trade in bubbly assets implements intergenerational transfers, while fiscal policy implements intragenerational transfers. Hence, while bubbles and fiscal policy are perfect substitutes in the deterministic economy, fiscal policy dominates bubbles in a stochastic economy. For plausible parameter values, a higher degree of dynamic inefficiency should lead to a higher sovereign debt

Drosophila simulans: a species with improved resolution in evolve and resequence studies

The combination of experimental evolution with high-throughput sequencing of pooled individuals-i.e., evolve and resequence (E&R)-is a powerful approach to study adaptation from standing genetic variation under controlled, replicated conditions. Nevertheless, E&R studies in Drosophila melanogaster have frequently resulted in inordinate numbers of candidate SNPs, particularly for complex traits. Here, we contrast the genomic signature of adaptation following ∼60 generations in a novel hot environment for D. melanogaster and D. simulans For D. simulans, the regions carrying putatively selected loci were far more distinct, and thus harbored fewer false positives, than those in D. melanogaster We propose that species without segregating inversions and higher recombination rates, such as D. simulans, are better suited for E&R studies that aim to characterize the genetic variants underlying the adaptive response.Neda Barghi, Raymond Tobler, Viola Nolte and Christian Schlöttere

Controlled biomineralization of magnetite (Fe₃O₄) by <i>Magnetospirillum gryphiswaldense</i>

Results from a study of the chemical composition and micro-structural characteristics of bacterial magnetosomes extracted from the magnetotactic bacterial strain Magnetospirillum gryphiswaldense are presented here. Using high-resolution transmission electron microscopy combined with selected-area electron diffraction and energy dispersive X-ray microanalysis, biogenic magnetite particles isolated from mature cultures were analysed for variations in crystallinity and particle size, as well as chain character and length. The analysed crystals showed a narrow size range (∼14-67 nm) with an average diameter of 46±6.8 nm, cuboctahedral morphologies and typical Gamma type crystal size distributions. The magnetite particles exhibited a high chemical purity (exclusively Fe3O4) and the majority fall within the single-magnetic-domain range

Geobase Information System Impacts on Space Image Formats

As Geobase Information Systems increase in number, size and complexity, the format compatability of satellite remote sensing data becomes increasingly more important. Because of the vast and continually increasing quantity of data available from remote sensing systems the utility of these data is increasingly dependent on the degree to which their formats facilitate, or hinder, their incorporation into Geobase Information Systems. To merge satellite data into a geobase system requires that they both have a compatible geographic referencing system. Greater acceptance of satellite data by the user community will be facilitated if the data are in a form which most readily corresponds to existing geobase data structures. The conference addressed a number of specific topics and made recommendations

Characterizing human habits in the lab

Habits pose a fundamental puzzle for those aiming to understand human behavior. They pervade our everyday lives and dominate some forms of psychopathology but are extremely hard to elicit in the lab. In this Registered Report, we developed novel experimental paradigms grounded in computational models, which suggest that habit strength should be proportional to the frequency of behavior and, in contrast to previous research, independent of value. Specifically, we manipulated how often participants performed responses in two tasks varying action repetition without, or separately from, variations in value. Moreover, we asked how this frequency-based habitization related to value-based operationalizations of habit and self-reported propensities for habitual behavior in real life. We find that choice frequency during training increases habit strength at test and that this form of habit shows little relation to value-based operationalizations of habit. Our findings empirically ground a novel perspective on the constituents of habits and suggest that habits may arise in the absence of external reinforcement. We further find no evidence for an overlap between different experimental approaches to measuring habits and no associations with self-reported real-life habits. Thus, our findings call for a rigorous reassessment of our understanding and measurement of human habitual behavior in the lab