scholarly journals Incentive value and spatial certainty combine additively to determine visual priorities

2020 ◽  
Author(s):  
K.G. Garner ◽  
H. Bowman ◽  
J.E. Raymond
Keyword(s):  
Expected Value ◽  
Visual Selection ◽  
Visually Guided ◽  
Spatial Cues ◽  
Incentive Value ◽  
Model Selection Approach ◽  
Selection Approach ◽  
Combine Information ◽  
The Brain ◽  
Behavioural Evidence

Abstract How does the brain combine information predictive of the value of a visually guided task (incentive value) with information predictive of where task-relevant stimuli may occur (spatial certainty)? Human behavioural evidence indicates that these two predictions may be combined additively to bias visual selection (Additive Hypothesis), whereas neuroeconomic studies posit that they may be multiplicatively combined (Expected Value Hypothesis). We sought to adjudicate between these two alternatives. Participants viewed two coloured placeholders that specified the potential value of correctly identifying an imminent letter target if it appeared in that placeholder. Then, prior to the target’s presentation, an endogenous spatial cue was presented indicating the target’s more likely location. Spatial cues were parametrically manipulated with regard to the information gained (in bits). Across two experiments, performance was better for targets appearing in high versus low value placeholders and better when targets appeared in validly cued locations. Interestingly, as shown with a Bayesian model selection approach, these effects did not interact, clearly supporting the Additive Hypothesis. Even when conditions were adjusted to increase the optimality of a multiplicative operation, support for it remained. These findings refute recent theories that expected value computations are the singular mechanism driving the deployment of endogenous spatial attention. Instead, incentive value and spatial certainty seem to act independently to influence visual selection.

scholarly journals Incentive value and spatial certainty combine additively to determine visual priorities

2017 ◽  
Author(s):  
K.G. Garner ◽  
H. Bowman ◽  
J.E. Raymond
Keyword(s):  
Expected Value ◽  
Visual Selection ◽  
Visually Guided ◽  
Spatial Cues ◽  
Incentive Value ◽  
Model Selection Approach ◽  
Selection Approach ◽  
Combine Information ◽  
The Brain ◽  
Behavioural Evidence

AbstractHow does the brain combine information predictive of the value of a visually guided task (incentive value) with information predictive of where task relevant stimuli may occur (spatial certainty)? Human behavioural evidence indicates that these two predictions may be combined additively to bias visual selection (additive hypothesis), whereas neuroeconomic studies posit that they may be multiplicatively combined (expected value hypothesis). We sought to adjudicate between these two alternatives. Participants viewed two coloured placeholders that specified the potential value of correctly identifying an imminent letter target if it appeared in that placeholder. Then, prior to the target’s presentation, an endogenous spatial cue was presented indicating the target’s more likely location. Spatial cues were parametrically manipulated with regards to the information gained (in bits). Across two experiments, performance was better for targets appearing in high versus low value placeholders and better when targets appeared in validly cued locations. Interestingly, as shown with a Bayesian model selection approach, these effects did not interact, clearly supporting the additive hypothesis. Even when conditions were adjusted to increase the optimality of a multiplicative operation, support for it remained. These findings refute recent theories that expected value computations are the singular mechanism driving the deployment of endogenous spatial attention. Instead, incentive value and spatial certainty seem to act independently to influence visual selection.

scholarly journals Understanding the nature of wealth and its effects on human fitness

2011 ◽  
Vol 366 (1563) ◽  
pp. 344-356 ◽  
Author(s):  
Monique Borgerhoff Mulder ◽  
Bret A. Beheim
Keyword(s):  
Phenotypic Traits ◽  
Human Diversity ◽  
Material Wealth ◽  
Fitness Consequences ◽  
Model Selection Approach ◽  
Holistic Understanding ◽  
Selection Approach ◽  
Household Assets ◽  
Selective Forces ◽  
Specific Contribution

Studying fitness consequences of variable behavioural, physiological and cognitive traits in contemporary populations constitutes the specific contribution of human behavioural ecology to the study of human diversity. Yet, despite 30 years of evolutionary anthropological interest in the determinants of fitness, there exist few principled investigations of the diverse sources of wealth that might reveal selective forces during recent human history. To develop a more holistic understanding of how selection shapes human phenotypic traits, be these transmitted by genetic or cultural means, we expand the conventional focus on associations between socioeconomic status and fitness to three distinct types of wealth—embodied, material and relational. Using a model selection approach to the study of women's success in raising offspring in an African horticultural population (the Tanzanian Pimbwe), we find that the top performing models consistently include relational and material wealth, with embodied wealth as a less reliable predictor. Specifically, child mortality risk is increased with few household assets, parent nonresidency, child legitimacy, and one or more parents having been accused of witchcraft. The use of multiple models to test various hypotheses greatly facilitates systematic comparative analyses of human behavioural diversity in wealth accrual and investment across different kinds of societies.

Contextual Modulation of Central Thalamic Delay-Period Activity: Representation of Visual and Saccadic Goals

2004 ◽  
Vol 91 (6) ◽  
pp. 2628-2648 ◽  
Author(s):  
Melanie T. Wyder ◽  
Dino P. Massoglia ◽  
Terrence R. Stanford
Keyword(s):  
Spatial Information ◽  
Delay Period ◽  
Visually Guided ◽  
Physical Stimulus ◽  
Behavioral Context ◽  
Thalamic Neurons ◽  
Contextual Modulation ◽  
Sensory Stimuli ◽  
Central Thalamus ◽  
Combine Information

This study examines the influence of behavioral context on the activity of visuomotor neurons in primate central thalamus. Neurons that combine information about sensory stimuli and their behavioral relevance are thought to contribute to the decision mechanisms that link specific stimuli to specific responses. We reported in a previous study that neurons in central thalamus carry spatial information throughout the instructed delay period of a visually guided delayed saccade task. The goal of the current study was to determine whether the delay-period activity of thalamic neurons is modulated by behavioral context. Single neurons were evaluated during performance of visually guided and memory-guided variants of a saccadic choice task in which a cue designated the response field stimulus as the target of a rewarded saccade or as an irrelevant distracter. The relative influence of the physical stimulus and context on delay-period activity suggested a minimum of 3 neural groups. Some neurons signaled the locations of visible stimuli regardless of behavioral relevance. Other neurons preferentially signaled the locations of current saccadic goals and did so even in the absence of the physical stimulus. A third group signaled only the locations of currently visible saccadic goals. For the latter 2 groups, activity was the product of both stimulus and context, suggesting that central thalamic neurons play a role in the context-dependent linkage of sensory signals and saccadic commands. More generally, these data suggest that the anatomical substrate of sensorimotor decision making may include the cortico-subcortical loops for which central thalamus serves as the penultimate synapse.

scholarly journals Similarities Between the AdS/CFT Correspondence and the Binding Problem

2019 ◽  
Author(s):  
Michael Elliott
Keyword(s):  
Black Holes ◽  
Subjective Experience ◽  
Condensed Matter ◽  
Boundary Surface ◽  
Theoretical Physics ◽  
Binding Problem ◽  
Physical Systems ◽  
Combine Information ◽  
The Brain

The binding problem refers to the puzzle of how the brain combines objects’ properties such as motion, color, shape, location, sound, etc., from diverse regions of the brain and forms a unified subjective experience. Holographic physical systems, recently discovered darlings of theoretical physics, began with research into black holes but have since evolved into the study of condensed matter systems in the laboratory like superfluids and superconductors. A primary example is the AdS/CFT correspondence. A recent conjecture of this correspondence suggests that holographic systems combine information from across a boundary surface, sort out the simplest description of said information, and, in turn, use it to determine the geometry of spacetime itself in the interior - a kind of geometric hologram. Although we would never tend to think of these two processes as related, in this paper we point out ten similarities between the two and show that holographic systems are the only physical systems that match the subjective and computational characteristics of the binding problem.

scholarly journals Using the past to estimate sensory uncertainty

2019 ◽  
Author(s):  
Ulrik Beierholm ◽  
Tim Rohe ◽  
Ambra Ferrari ◽  
Oliver Stegle ◽  
Uta Noppeney
Keyword(s):  
Temporal Dynamics ◽  
Visual Signals ◽  
Perceptual Inference ◽  
Reliability Estimates ◽  
Uncertainty Estimates ◽  
Classical Models ◽  
Past Experiences ◽  
Combine Information ◽  
Sensory Uncertainty ◽  
The Brain

AbstractTo form the most reliable percept of the environment, the brain needs to represent sensory uncertainty. Current theories of perceptual inference assume that the brain computes sensory uncertainty instantaneously and independently for each stimulus.In a series of psychophysics experiments human observers localized auditory signals that were presented in synchrony with spatially disparate visual signals. Critically, the visual noise changed dynamically over time with or without intermittent jumps. Our results show that observers integrate audiovisual inputs weighted by sensory reliability estimates that combine information from past and current signals as predicted by an optimal Bayesian learner or approximate strategies of exponential discountingOur results challenge classical models of perceptual inference where sensory uncertainty estimates depend only on the current stimulus. They demonstrate that the brain capitalizes on the temporal dynamics of the external world and estimates sensory uncertainty by combining past experiences with new incoming sensory signals.

scholarly journals Patterns of selection against centrosome amplification in human cell lines

2021 ◽  
Vol 17 (5) ◽  
pp. e1008765
Author(s):  
Marco António Dias Louro ◽  
Mónica Bettencourt-Dias ◽  
Claudia Bank
Keyword(s):  
Cell Lines ◽  
Human Cell ◽  
Centrosome Amplification ◽  
Population Heterogeneity ◽  
Human Cell Lines ◽  
Inference Method ◽  
Accuracy And Precision ◽  
Model Selection Approach ◽  
Selection Approach ◽  
Cancer Cell Population

The presence of extra centrioles, termed centrosome amplification, is a hallmark of cancer. The distribution of centriole numbers within a cancer cell population appears to be at an equilibrium maintained by centriole overproduction and selection, reminiscent of mutation-selection balance. It is unknown to date if the interaction between centriole overproduction and selection can quantitatively explain the intra- and inter-population heterogeneity in centriole numbers. Here, we define mutation-selection-like models and employ a model selection approach to infer patterns of centriole overproduction and selection in a diverse panel of human cell lines. Surprisingly, we infer strong and uniform selection against any number of extra centrioles in most cell lines. Finally we assess the accuracy and precision of our inference method and find that it increases non-linearly as a function of the number of sampled cells. We discuss the biological implications of our results and how our methodology can inform future experiments.

Sign in / Sign up

Export Citation Format

Share Document