Psychophysical Theory Research Articles

The coherent organization of dynamic visual images

Biological vision relies on the intrinsic spatiotemporal structure of a continuously flowing image stream. We review converging psychophysical and physiological evidence about the structure and precision of the perceived spatiotemporal organization of dynamic images. Visual acuity, temporal resolution, and contrast sensitivity have been found to involve (a) motion-produced increases in image contrast, (b) coherent phase relations among temporally varying retinal signals, and (c) physiological preservation of spatiotemporal structure from retina to cortex. Moreover, psychophysical theory and evidence show that the spatiotemporal structure of dynamic retinal images carries precise information for perceiving surfaces and motions—consistent with the corresponding differential structures of spatiotemporal images and environmental surfaces.

Successful discrimination of tiny numerical differences

Are there some differences so small that we cannot detect them? Are some quantities so similar (e.g., the number of spots on two speckled hens) that they simply look the same to us? Although modern psychophysical theories such as Signal Detection Theory would predict that, with enough trials, even minute differences would be perceptible at an above-chance rate, this prediction has rarely been empirically tested for any psychological dimension, and never for the domain of number perception. In an experiment with over 400 adults, we find that observers can distinguish which of two collections has more dots from a brief glance. Impressively, observers performed above chance on every numerical comparison tested, even when discriminating a comparison as difficult as 50 versus 51 dots. Thus, we present empirical evidence that numerical discrimination abilities, consistent with SDT, are remarkably fine-grained.

Discrete choice models with multiplicative stochasticity in choice environment variables: Application to accommodating perception errors in driver behaviour models

This paper presents a mixed multinomial logit-based discrete choice modelling framework to accommodate decision-makers’ errors in perceiving choice environment variables that do not vary across choice alternatives. An analysis is undertaken to evaluate two different ways of specifying errors in the choice environment variables in discrete choice models – (a) the additive specification and (b) the multiplicative specification. Between these two approaches, the multiplicative error specification is consistent with psychophysical theories of human perception of physical quantities in that the variability in perception tends to be greater for quantities of greater magnitude. Further, it is shown that models with an additive error specification run into parameter (un)identifiability problems if the analyst attempts to accommodate errors in several variables. In contrast, models with multiplicative errors in variables allow separate identification of stochasticity in as many variables as needed, as long as those variables have a significant influence on the choice outcome.The usefulness of the proposed framework with multiplicative errors is demonstrated through simulation experiments and an empirical application for analysing driver behaviour while considering drivers’ errors in perceiving traffic environment variables. The empirical analysis is carried out using space-time trajectories of vehicles from a heterogeneous, disorderly (HD) traffic stream in Chennai, India. Results suggest that the proposed model, with power lognormal distributed multiplicative errors in traffic environment variables, outperformed the typically used mixed logit models with random coefficients (uncorrelated and correlated) or error components. Further, allowing for perception errors in traffic environment variables was found to be more important than allowing unobserved heterogeneity in the drivers’ sensitivity to those variables. In addition, the empirical model offers interesting insights into the extent of variability due to perception errors in different traffic environment variables.

Exploring psychophysical measurement in landscape aesthetics: Validity, reliability and signal detection via single-versus opposing-construct rating scales, with or without zeros

Surveys eliciting qualitative judgments of environments might have an objective psychophysical basis. They can employ numeric, single-construct, integer rating scales or ratio scales between opposing negative and positive end-point constructs. Each stimulus can be measured by different ‘averaging’ methods across subjects' ratings. The impacts of these choices on data reliability and validity were investigated. Three different rating scales were presented to different sets of subjects who rated the same stimuli. Eighty photos of various forests and timber harvests were rated for (1) scenic beauty on a 1 to 10 scale, (2) ugliness or scenic beauty on a −5 to +5 scale, or (3) the same bipolar scale but without a central zero value. Ratings from each photo from one rating scale were averaged and ‘averaged’ again by the Scenic Beauty Estimate (SBE) signal detection algorithm. Distributions of the raw and averaged ratings were examined to explore validity by conformance with psychophysical theory. Ratings from the bipolar scale without a zero exhibited the most evidence of validity across a wider range, indicating that it best conformed with discrimination of photos' perceived beauty and ugliness along a shared, psychophysical gradient. Averaged ratings from the 1 to 10 scale produced the most reliable data, while its SBEs were slightly less reliable but with more stable errors. These ratings exhibited poor validity among low-beauty photos The bipolar rating scale that included a zero value was least reliable and valid, particularly across its ratio SBEs. All rating scales' average ratings or SBEs exhibited acceptable reliability.

The threshold of awareness as an empirical given and as a logical inevitability

The nature of the sensory threshold and approaches to solving the threshold problem in psychophysics are discussed. There were presented experimental results, empirical facts that do not fully correspond to existing psychophysical theories and do not receive an explanation in line with modern approaches. It was concluded that the explanation of the thresholds without description of the participation of consciousness raises doubts. A new look at the nature of thresholds is proposed, in which the threshold is considered as an inevitable consequence of the processes of classification and categorization. Due to the fact that the operations of identification of the non-identical and discernment of the indiscernible are mandatoryin the act of cognition, a zone is formed, within which objectively different elements are identified in consciousness andrelate to the same class. This zone exists across the entire spectrum of cognitive tasks, including detection and discrimination. Thresholds fix the boundaries of this zone. Thus, the problem of the threshold requires a description of the work of not so physiological as cognitive mechanismsfor its solution.

Observer Dependent Biases of Quantum Randomness

Quantum mechanics (QM) proposes that a quantum system measurement does not register a pre-existing reality but rather establishes reality from the superposition of potential states. Measurement reduces the quantum state according to a probability function, the Born rule, realizing one of the potential states. Consequently, a classical reality is observed. The strict randomness of the measurement outcome is well-documented (and theoretically predicted) and implies a strict indeterminacy in the physical world’s fundamental constituents. Wolfgang Pauli, with Carl Gustav Jung, extended the QM framework to measurement outcomes that are meaningfully related to human observers, providing a psychophysical theory of quantum state reductions. The Pauli-Jung model (PJM) proposes the existence of observer influences on quantum measurement outcomes rooted in the observer’s unconscious mind. The correlations between quantum state reductions and (un)conscious states of observers derived from the PJM and its mathematical reformulation within the model of pragmatic information (MPI) were empirically tested. In all studies, a subliminal priming paradigm was used to induce a biased likelihood for specific quantum measurement outcomes (i.e., a higher probability of positive picture presentations; Studies 1 and 2) or more pronounced oscillations of the evidence than expected by chance for such an effect (Studies 3 and 4). The replicability of these effects was also tested. Although Study 1 found strong initial evidence for such effects, later replications (Studies 2 to 4) showed no deviations from the Born rule. The results thus align with standard QM, arguing against the incompleteness of standard QM in psychophysical settings like those established in the studies. However, although no positive evidence exists for the PJM and the MPI, the data do not entirely falsify the model’s validity.

Internal references in cross-modal judgments: A global psychophysical perspective.

We are able to compare intensities across different sorts of stimuli, like in matching the brightness of visual stimuli of different hue, or the loudness of auditory stimuli of different spectral shapes. We can even match the brightness of a visual stimulus to the loudness of a tone, and vice versa. The term cross-dimensional matching is used to subsume these kinds of intra- and cross-modal tasks. The often replicated regression effect in cross-dimensional matching relates to the observation that the intensity of whatever stimulus is adjusted exhibits a tendency toward some mean magnitude, which is interpreted as serving as an internal reference. Internal references, however, are not part of psychophysical theory in the tradition of Stevens. They form a key ingredient for the theory of global psychophysics initiated by R. Duncan Luce, which also makes explicit Stevens' assumption of an underlying ratio scale of perceived intensity to which all sensations map, and renders it empirically testable. The present article generalizes Luce's theory of cross-dimensional magnitude production (Luce et al., 2010) to integrate potentially role-dependent internal references (pertaining to the standard, or the adjusted stimulus) as suggested by the regression effect. Reconsidering available empirical evidence for magnitude production and matching experiments in the light of these theoretical developments leads to a coherent picture. The results indicate that internal references are role-dependent in cross-dimensional tasks (intra- or cross-modal), but role-independent in intra-dimensional tasks. Moreover, predictions derived from the generalized theory provide a close fit to classical matching data. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Optimal allocation of quantized human eye depth perception for multi-focal 3D display design.

Creating immersive 3D stereoscopic, autostereoscopic, and lightfield experiences are becoming the center point of optical design of future head mounted displays and lightfield displays. However, despite the advancement in 3D and light field displays, there is no consensus on what are the necessary quantized depth levels for such emerging displays at stereoscopic or monocular modalities. Here we start from psychophysical theories and work toward defining and prioritizing quantized levels of depth that would saturate the human depth perception. We propose a general optimization framework, which locates the depth levels in a globally optimal way for band limited displays. While the original problem is computationally intractable, we manage to find a tractable reformulation as maximally covering a region of interest with a selection of hypographs corresponding to the monocular depth of field profiles. The results indicate that on average 1731 stereoscopic and 7 monocular depth levels (distributed optimally from 25 cm to infinity) would saturate the visual depth perception. Such that adding further depth levels adds negligible improvement. Also the first 3 depth levels should be allocated at (148), then (83, 170), then (53, 90, 170) distances respectively from the face plane to minimize the monocular error in the entire population. The study further discusses the 3D spatial profile of the quantized stereoscopic and monocular depth levels. The study provides fundamental guidelines for designing optimal near eye displays, light-field monitors, and 3D screens.

Bohm`s Quantum Potential Approach to Consciousness from the Perspective of a Four-Valued Logic

Parallel to David Bohm´s development of a realistic interpretation of quantum physics, German philosopher and logician Gotthard Günther worked on a generalization of the classical two-valued logic to satisfy the ontological requirements of quantum physics as well as of cybernetics. Both of these new disciplines introduced information and consciousness into the terminology of science. These terms and concepts need to be reflected in logic, ontology and the theory of science. David Bohm suggested an expansion of his own model by generalization and iteration of the quantum potential to include consciousness and mental states into a new psycho-physical theory. This article proposes Günther´s four-valued logical system of meaning/reflection as a theoretical scientific frame for this expansion of Bohm´s theory and discusses its ontological implications.

“The Hour of Woman” and Edith Stein: Catholic New Feminist Responses to Essentialism

This article examines how Edith Stein’s philosophical and theological anthropology is foundational to the “new feminism” that both Paul VI and John Paul II called for in the wake of the Second Vatican Council. In particular, this article shows how Stein helps to respond to Simone de Beauvoir’s argument that taking women’s biology into consideration leads to essentialism with political implications. This article outlines main themes in the new feminism, and gives a brief overview of the ideas about the “hour of woman” and the “feminine genius” pronounced by popes Paul VI and John Paul II. This article then describes and analyzes Stein’s psycho-physical theory of the human person. Finally, this article considers the importance of Stein’s thought for feminist theology, with brief application to the issue of the ordination of women to the priesthood.

Ankle inversion discrimination in standing and landing

Introduction: Ankle sprains, which usually occur during landing in ankle inversion, are the most common injuries in sport. Research has shown that superior ankle proprioception is associated with a lower risk of ankle sprain. In order to improve ecological validity of the ankle test, we developed the ankle Active Movement Extent Discrimination Apparatus (AMEDA) to assess ankle proprioception in standing. In the current study, we further developed the Ankle Inversion Discrimination Apparatus for Landing (AIDAL), based on the same psychophysical theory. The aim of the present study was to explore the relationship between the two tests.

Seventy Years in Philosophy of Mind: An Overview, with Emphasis on the Issue of Mental Causation

This paper is an opinionated overview of major developments in philosophy of mind during the past seventy years, with emphasis on the issue of mental causation. Its most prominent positions all embrace a broadly “naturalistic” or “materialistic” conception of human beings, and of mentalityand its place in nature. Included in this paper are discussions of analytical behaviorism, the psychophysical identity theory, functionalism, multiplerealizability and strong multiple realizability, supervenience, the causal exclusion problem, phenomenal mental states, wide content, contextualist causal compatibilism, agentive phenomenology, and the agent-exclusion problem.

Philosophy and Science Dialogue: Mental Causation

This paper is a dialogue between Thalia Wheatley and Terence Horgan. Horgan maintains that philosophy is a broadly empirical discipline, and that philosophical theorizing about how concepts work treats certain intuitions about proper concept-usage as empirical data. He holds that the possibility of strong multiple realizability undermines the psychophysical identity theory. He holds that the concept of causation is governed by implicit contextual parameters, and that this dissolves Kim’s problem of “causal exclusion.” He holds that the concept of free will is governed by implicit contextual parameters, and that free-will attributions are often true, in typical contexts, even if determinism is true. Thalia Wheatley holds that the concept of multiple realizability hinges on the level of abstraction discussed and that neuroscientific data does not yet support multiple realizability of mental states from specific, high resolution brain states. She also holds that compatibilism redefines the concept of free will in ways that bear little resemblance to the common understanding―that of being free to choose otherwise in the moment. She maintains that this folk understanding is incompatible with the brain as a physical system and is not rescued by concepts of context and capacity.

Self-consciousness: an I-World patterned process model

The self is herein recognized as self-consciousness, a broad dynamic system of self-recognition and self-reference. Eight psychosomatic and extended cognitive functions working as an interactive whole are proposed to constitute self-consciousness: (1) somatic domain and body image; (2) situation and domestic range; (3) agency and power to act; (4) introspection, mindfulness, and metacognition; (5) first person discourse and appropriation; (6) episodic memory, autobiography, and role; (7) attribution and alterity; (8) conscience, moral consciousness, and ethical stance. These functions, complemented with considerations about depersonalization and selflessness, are briefly defined and described. These subsystems may work independently but they may interact and variably coalesce according to the demands of the task. Since self-awareness would require a dynamic swarm-like activation pattern of the cluster, the self does not reside in particular brain sites or networks but depends on top-down and bottom-up mechanisms coupled with incoming and outgoing sensory-motor data loops. This psychophysical theory avoids the swing between internal and external elements in favor of an embracing I-World patterned process that comprises neural, bodily, behavioral, environmental, and social dimensions converging in the construction and expression of self-conscious and personal identity experiences integrated by a participant brain.

Das relationale Apriori Wiens / Das städtische Apriori des Relationalismus: Stadt, Raum und Text in Robert Musils <i>Mann ohne Eigenschaften</i>

Asking if Robert Musil's The Man without Qualities can be read as a city novel, this paper links modern concepts of space (from the contexts of philosophical, biological, and psycho-physical theories around 1900) to Musil's prose, which is described as a praxis of “space writing”. The author presents this kind of space writing as an attempt to cope with the modern city, going beyond the classical episteme of representation. The paper concludes that modern cities constitute a dispositif for developing new concepts of space and new practices of writing.

Subjective intensity: Behavioral laws, numerical representations, and behavioral predictions in Luce’s model of global psychophysics

This article summarizes the theoretical work of R. Duncan Luce towards a unified psychophysical theory of the percepts of all intensive domains. Also summarized are the empirical evaluations of it carried out to date. The theory is a comprehensive application of axiomatic measurement theory. The approach, mimicking classical static physics, is based on behavioral–and testable–axiomatic invariances that imply a numerical representation (a measurement scale) and its properties. The empirical work involves interpreting the primitives of the theory in a domain and then evaluating the behavioral properties. If supported, the representations follow from the properties, forming a descriptive model for that domain. The theory differs in some details depending on whether percepts involve an interplay between two sensors (2-D) (e.g., two eyes/ears) or just one (1-D). The theory has been substantially evaluated and supported in the 2-D domains of loudness, brightness, and perceived contrast. Empirical work for 1-D domains is less complete. Novel inferences and predictions flow from the theory and several of these, along with empirical work, are summarized.

Distinct effects of contrast and color on subjective rating of fearfulness.

Natural scenes provide important affective cues for observers to avoid danger. From an adaptationist perspective, such cues affect the behavior of the observer and shape the evolution of the observer’s response. It is evolutionarily significant for individuals to extract affective information from the environment as quickly and as efficiently as possible. However, the nearly endless variations in physical appearance of natural scenes present a fundamental challenge for perceiving significant visual information. How image-level properties, such as contrast and color, influence the extraction of affective information leading to subjective emotional perception is unclear. On the one hand, studies have shown that visual perception and emotional perception seem to interact with each other at the earliest stages in cortical processing. On the other hand, it is important for high-level subjective ratings to be invariant to low-level visual properties. Using a psychophysical approach and signal detection theory (SDT), we tested how contrast and color influenced fearfulness ratings of a set of natural scene pictures that varied in contents and in levels of fearfulness. Image contrast influenced perceptual sensitivity but not the decision criterion of fearfulness rating, whereas color affected the decision criterion but not perceptual sensitivity. These results show that different low-level visual features contribute independently to sensitivity or decision criterion in affective perception, suggesting distinct interactions between visual cognition and affective processing. Specifically, our naturalistic approach using a novel stimulus set, combined with SDT, has demonstrated two dissociable types of cognitive mechanisms underlying how image-level properties leverage the extraction of affective information in natural vision.

Modeling shortest path selection of the ant Linepithema humile using psychophysical theory and realistic parameter values

The emergence of self-organizing behavior in ants has been modeled in various theoretical approaches in the past decades. One model explains experimental observations in which Argentine ants (Linepithema humile) selected the shorter of two alternative paths from their nest to a food source (shortest path experiments). This model serves as an important example for the emergence of collective behavior and self-organization in biological systems. In addition, it inspired the development of computer algorithms for optimization problems called ant colony optimization (ACO). In the model, a choice function describing how ants react to different pheromone concentrations is fundamental. However, the parameters of the choice function were not deduced experimentally but freely adapted so that the model fitted the observations of the shortest path experiments. Thus, important knowledge was lacking about crucial model assumptions. A recent study on the Argentine ant provided this information by measuring the response of the ants to varying pheromone concentrations. In said study, the above mentioned choice function was fitted to the experimental data and its parameters were deduced. In addition, a psychometric function was fitted to the data and its parameters deduced. Based on these findings, it is possible to test the shortest path model by applying realistic parameter values. Here we present the results of such tests using Monte Carlo simulations of shortest path experiments with Argentine ants. We compare the choice function and the psychometric function, both with parameter values deduced from the above-mentioned experiments. Our results show that by applying the psychometric function, the shortest path experiments can be explained satisfactorily by the model. The study represents the first example of how psychophysical theory can be used to understand and model collective foraging behavior of ants based on trail pheromones. These findings may be important for other models of pheromone guided ant behavior and might inspire improved ACO algorithms.

Computer-Aided Color Aesthetic Evaluation Method Based on the Combination of Form and Color

This paper presents a new method of color aesthetic evaluation based on the combination of form and color. According to the human visual physiological and psychological characteristics, this paper first proposes a new form-color field theory for the coupled form-color aesthetic evaluation based on the psychophysical field theory and the Moon and Spencer model. Second, it builds a coupled form-color topological graph for describing their interaction and develops a strength calculation algorithm for color harmony based on the new form-color field theory. Finally, it develops an aesthetic measure evaluation model for coupled form-color fields to evaluate the new theory. The experiment results show that the new coupled form-color aesthetic evaluation method is useful and can be integrated into an intelligent evaluation process for color design scheme.

Pheromone communication in ants: a detailed analysis of concentration-dependent decisions in three species

The collective behavior of ants and the emergence of self-organizing patterns in ant colonies have been explained with various theoretical approaches based on models of trail following behavior elicited by pheromones. Although existing models can explain collective behavior of ants, there is little empirical evidence on how ants precisely respond to various pheromone concentrations. Thus, important knowledge is lacking about how much realistic description of ant behavior can be provided by the models and their underlying mathematical functions. To fill in this gap, we conducted experiments with three different ant species to explore their responses to varying concentrations of pheromones that elicit ants’ trail following behavior. We found that ants’ decision making processes in trail following are best explained by psychophysical theory (PT), which describes the relationship between physical stimuli, sensory perception and decision making in humans, other primates, birds and insects. Furthermore, the theory provides clear definitions of biological parameters, such as detection- and discrimination thresholds. The species studied were distinctively different in the shape and parameters of their psychometric functions, which we attribute to specific adaptions to their environment. The observed differences are discussed in relation to their natural trail following behaviors. Our study opens a new perspective of understanding and explaining important aspects of collective ant behavior using a well-established theory of perception.