Bounded Rationality in C. elegans

Abstract

Rational choice theory in economics assumes optimality indecision-making.One of the basic axioms of economic rationality is "Independence of Irrelevant Alternatives" (IIA), according to which a preference ratio between two options should be unaffected by introducing additional alternatives to the choice set.Violations of IIA have been demonstrated in both humans and in various animals, and could therefore stem from common neuronal constraints. We . CC-BY-NC-ND 4.0 International license not peer-reviewed) is the author/funder. It is made available under aThe copyright holder for this preprint (which was . http://dx.doi.org/10.1101/257535 doi: bioRxiv preprint first posted online Jan. 31, 2018; used the nematode Caenorhabditis elegans, an animal with only 302 neurons and a fully mapped connectome, to examine when and why economic rationality and violations of rationality occur. We developed tests for IIA violations by characterizing the choices that C. elegans make in olfactory chemotaxis assays. In each assay, we exposed the worm to different odors that activate only specific neurons, thus involving in the choice process only defined neuronal networks, and tested whether particular neuronal architectures are prone to producing irrational choices. We found that C. elegans are capable of maintaining robust binary olfactory preferences irrespectively of the presence of a third attractive odor. However, in very specific olfactory contexts, which we term asymmetric overlaps, the preference ratio between the two odors was altered due to the addition of a third inferior odor, in a manner that violates IIA, and in certain cases can be considered "irrational" based on the economic definition of rationality. Our results suggest that different network configurations vary in their propensity to give rise to inconsistent decision making. Thus, non-optimal choices, assumed to be an outcome of high-order cognitive and mental processes, could result from much more basic attributes of neuronal activity and constrained computational mechanisms.

Traffic-Related Air Pollution and Breast Cancer Risk: A Systematic Review and Meta-Analysis of Observational Studies

“…Studies assessing the effect of TRAP exposure on breast cancer risk are presented in Table 1. Thirteen cohort studies [22][23][24]26,34,35,[39][40][41][42][43][44][45], including a pooled analysis of 15 cohorts [26], seven case-control studies [25,29,37,[46][47][48][49], and one nested case-control study [50], published between 1996 and 2022, were identified. Eight were conducted in the United States [35,37,39,42,43,[45][46][47], five in Canada [23,29,41,48,49], two in Denmark [22,40], two in France [25,50], one in Israel [44], one in Germany [34], one in Taiwan [24], and one was a pooled analysis of 15 cohorts from nine European countries [26].…”

“…e Kriging: n = 2693 (NO x ), n = 2727 (NO 2 ); LUR: n = 2557 (NO x ), n = 2590 (NO 2 ); CALINE4: 2352 (NO x ). Regarding the enrollment period, three studies started in the 1980s [41,42,46], nine in the 1990s [22,29,35,37,40,45,47,48,50], and eight in the 2000s [23][24][25]34,39,43,44,49]. Enrolment periods started in 1980 in the earliest study and in 2014 for the most-recent one.…”

“…Three studies were conducted only on postmenopausal women [26,29,49], and eleven studies performed subgroup analyses according to menopausal status [25,37,39,[41][42][43][45][46][47][48]50]. The selection of cases was based on cancer registries in eight studies [23,26,35,40,41,44,45,48], hospital and physician list in six studies [25,29,37,46,47,49], selfadministered questionnaires in six studies [22,26,39,42,45,50], and health insurance databases in two studies [24,34].…”

“…Eleven studies analyzed NO 2 exposure [23][24][25]29,34,[39][40][41]45,[48][49][50], one on NO x [44] and two on both NO 2 and NO x [26,35]. Exposure assessment of these reports were based on LUR models, except for three studies that used kriging and dispersion models [25,39,40] and one study using measures from monitoring stations [24].…”

“…Figure 2 synthetizes the exposure assessment details on the addresses used, timing of exposure, timing of exposure assessment, and range of mean pollutant concentrations. Overall, eleven studies used the subjects' residential history [23][24][25]35,37,40,42,[46][47][48]50] and nine studies the baseline address [22,26,34,39,41,44,45,49,52] for exposure assessment. More specifically, regarding the timing of exposure, studies estimated exposures at baseline [22,26], during the follow-up until the index date [24,25,35,40,48,50,53], and during a period (7-20 years) prior to diagnosis or the index year [23,37,47,48].…”