Perceptual Independence Research Articles

Multidimensional signal detection modeling reveals Gestalt-like perceptual integration of face emotion and identity.

Numerous studies have tested the hypothesis that facial identity and emotional expression are independently processed, but a solid conclusion has been difficult to reach, with the literature showing contradictory results. We argue that this is partly due to different researchers using different definitions of perceptual integration and independence, usually vague and/or simply operational, and also due to lack of proper stimulus control. Here, we performed a study using three-dimensional realistic computer-generated faces for which the discriminability of identities and expressions, the intensity of the expressions, and low-level features of the faces were controlled. A large number of participants, distributed across twelve experimental groups, performed identification tasks for the six basic emotional expressions and the neutral expression (between 2018 and 2019). A multidimensional signal detection model was utilized to analyze the data, which allowed us to dissociate between multiple formally defined notions of independence and holism. Results showed strong and robust violations of perceptual independence that were consistent across all experiments and suggest Gestalt-like perceptual integration of face identity and expression. To date, our results provide the strongest evidence for holistic/Gestalt processing found among face perception studies that have used formal definitions of independence and holism. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Effects of shifts in response preferences on characteristics of representation and real-time processing: An application to the Hering illusion.

The multidimensional generalization of signal detection theory known as General Recognition Theory (GRT, Ashby & Townsend, Psychological Review, 93, 154-179 1986) has been used to model and characterize the ways in which changes in encoded perceptual information and the application of decisional operators can produce patterns in behavior that are consistent with notions such as configural processing and representation. In particular, a set of studies (e.g., Cornes et al.,, 2011; Wenger & Ingvalson; 2002, 2003) have shown how decisional influences might exert themselves in situations of configural perception, such that effects such as the Thatcher illusion can be obtained by way of shifts in decisional criteria. The present investigation brought to bear the combined tools of GRT and Systems Factorial Technology (SFT, Little et al.,, 2017; Townsend & Nozawa, 1995) with a classical illusion, to show that it is possible to induce a shift in a decisional criterion by way of varying payoffs and that this shift is accompanied by regular changes in the workload capacity statistic. The combined sets of analyses on the same stimuli reveal orderly effects on the decisional criteria (i.e., the signal detection parameter c), report independence (suggesting perceptual independence), invariant measures of sensitivity (i.e., the signal detection parameter [Formula: see text]),and exhaustive parallel processing accompanied by super capacity. We therefore propose wider use of the combined sets of tools, further exploration of the ability of decisional alterations to affect processing times while leaving accuracy largely unscathed, and reaching out to explore more of the information processing mechanisms of classical illusions.

Macronutrient Sensing in the Oral Cavity and Gastrointestinal Tract: Alimentary Tastes.

There are numerous and diverse factors enabling the overconsumption of foods, with the sense of taste being one of these factors. There are four well established basic tastes: sweet, sour, salty, and bitter; all with perceptual independence, salience, and hedonic responses to encourage or discourage consumption. More recently, additional tastes have been added to the basic taste list including umami and fat, but they lack the perceptual independence and salience of the basics. There is also emerging evidence of taste responses to kokumi and carbohydrate. One interesting aspect is the link with the new and emerging tastes to macronutrients, with each macronutrient having two distinct perceptual qualities that, perhaps in combination, provide a holistic perception for each macronutrient: fat has fat taste and mouthfeel; protein has umami and kokumi; carbohydrate has sweet and carbohydrate tastes. These new tastes can be sensed in the oral cavity, but they have more influence post- than pre-ingestion. Umami, fat, kokumi, and carbohydrate tastes have been suggested as an independent category named alimentary. This narrative review will present and discuss evidence for macronutrient sensing throughout the alimentary canal and evidence of how each of the alimentary tastes may influence the consumption of foods.

Perceptual independence increases with depth in a generative adversarial network

Perceptual independence increases with depth in a generative adversarial network

Perceptual learning produces perceptual objects.

In their seminal study of chess expertise, Simon and Chase (Chase & Simon, 1973; Simon & Chase, 1973) proposed that perceptual learning was a necessary component of skill acquisition. In their view, acquisition of skill results from the strategic use of learning at multiple levels to adaptively overcome inherent limitations. The knowledge acquired by way of perceptual learning that supported increasingly sophisticated perceptual discrimination processes, according to Simon and Chase, was referred to as a chunk. The chunk was conceptualized as a meaningful complex set of features that abstracted the notion of a perceptual object. Simon and Chase further suggested that meaningful combinations of chunks could be combined to form configurations (Simon & Chase, 1973, p. 399). The present study addresses this idea by framing the notion of a chunk in terms of two formal metatheories, one that addresses representation (Ashby & Townsend, 1986) and one that addresses processing (Townsend & Nozawa, 1995), and tests the prediction that perceptual learning produces organized perceptual objects (chunks). Two experiments combine behavioral and electroencephelographic (EEG) measures to show that perceptual learning produces (a) a shift from perceptual independence and separability to violations of separability, and (b) shifts from limited-capacity serial processing to supercapacity parallel processing. The evidence from both experiments is strong and consistent: perceptual learning does indeed induce chunking-the production of perceptual objects, and the foundation of perceptual expertise. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Assessing User Mental Workload for Smartphone Applications With Built-In Sensors

This work proposes a novel three-dimensional model to represent users’ mental workload when using smartphone applications. We validate this model by studying the factors’ perceptual independence and interactions using data collected from 22 participants. By analyzing the correlations between the factors of mental workload and tap strength captured by smartphones’ built-in sensors, we discover tap strength is significantly affected by and can potentially be used to infer the hidden states of mental workload. We build a prototype system and show the effectiveness of assessing mental workload using tap strength without additional human or device costs in both laboratory and real-world settings.

Testing Separability and Independence of Perceptual Dimensions with General Recognition Theory: A Tutorial and New R Package (grtools).

Determining whether perceptual properties are processed independently is an important goal in perceptual science, and tools to test independence should be widely available to experimental researchers. The best analytical tools to test for perceptual independence are provided by General Recognition Theory (GRT), a multidimensional extension of signal detection theory. Unfortunately, there is currently a lack of software implementing GRT analyses that is ready-to-use by experimental psychologists and neuroscientists with little training in computational modeling. This paper presents grtools, an R package developed with the explicit aim of providing experimentalists with the ability to perform full GRT analyses using only a couple of command lines. We describe the software and provide a practical tutorial on how to perform each of the analyses available in grtools. We also provide advice to researchers on best practices for experimental design and interpretation of results when applying GRT and grtools

Feature binding in visual short term memory: A General Recognition Theory analysis.

Creating and maintaining accurate bindings of elementary features (e.g., color and shape) in visual short-term memory (VSTM) is fundamental for veridical perception. How are low-level features bound in memory? The present work harnessed a multivariate model of perception - the General Recognition Theory (GRT) - to unravel the internal representations underlying feature binding in VSTM. On each trial, preview and target colored shapes were presented in succession, appearing in either repeated or altered spatial locations. Participants gave two same/different responses: one with respect to color and one with respect to shape. Converging GRT analyses on the accuracy confusion matrices provided substantial evidence for binding in the form of violations of perceptual independence at the level of the individual stimulus, such that positive correlations were obtained when both features repeated or alternated together, while negative correlations were obtained when one feature repeated and the other alternated. This "cloverleaf" GRT pattern of binding was similar whether the spatial location of the preview and target repeated or altered. The current results are consistent with: (a) the discrete memory "slots" model of VSTM, and (b) the notion that spatial location is not necessary for the formation of "object files." The GRT approach presented here offers a viable quantitative model for testing various questions regarding feature binding in VSTM.

Separate Perceptual and Neural Processing of Velocity- and Disparity-Based 3D Motion Signals.

Recent human neuroimaging and monkey electrophysiology have revealed 3D motion selectivity in area MT, which is driven by both velocity-based and disparity-based 3D motion signals. However, to elucidate the neural mechanisms by which the brain extracts 3D motion given these binocular signals, it is essential to understand how-or indeed if-these two binocular cues interact. We show that velocity-based and disparity-based signals are mostly separate at the levels of both fMRI responses in area MT and perception. Our findings suggest that the two binocular cues for 3D motion might be processed by separate specialized mechanisms.

Modeling the voice source in terms of spectral slopes

A psychoacoustic model of the voice source spectrum is proposed. The model is characterized by four spectral slope parameters: the difference in amplitude between the first two harmonics (H1-H2), the second and fourth harmonics (H2-H4), the fourth harmonic and the harmonic nearest 2 kHz in frequency (H4-2 kHz), and the harmonic nearest 2 kHz and that nearest 5 kHz (2 kHz-5 kHz). As a step toward model validation, experiments were conducted to establish the acoustic and perceptual independence of these parameters. In experiment 1, the model was fit to a large number of voice sources. Results showed that parameters are predictable from one another, but that these relationships are due to overall spectral roll-off. Two additional experiments addressed the perceptual independence of the source parameters. Listener sensitivity to H1-H2, H2-H4, and H4-2 kHz did not change as a function of the slope of an adjacent component, suggesting that sensitivity to these components is robust. Listener sensitivity to changes in spectral slope from 2 kHz to 5 kHz depended on complex interactions between spectral slope, spectral noise levels, and H4-2 kHz. It is concluded that the four parameters represent non-redundant acoustic and perceptual aspects of voice quality.

Half a century of research on Garner interference and the separability-integrality distinction.

Research in the allied domains of selective attention and perceptual independence has made great advances over the past 5 decades ensuing from the foundational ideas and research conceived by Wendell R. Garner. In particular, Garner's speeded classification paradigm has received considerable attention in psychology. The paradigm is widely used to inform research and theory in various domains of cognitive science. It was Garner who provided the consensual definition of the separable-integral partition of stimulus dimensions, delineating a set of converging operations sustaining the distinction. This distinction is a pillar of today's cognitive science. We review the key ideas, definitions, and findings along 2 paths of the evolution of Garnerian research: selective attention, with a focus on Garner interference and its relation to the Stroop effect, and divided attention, with focus on perceptual independence gauged by multivariate models of perception. The review tracks developments in a roughly chronological order. Our review is also integrative as we follow the evolution of a set of nascent ideas into the vast multifaceted enterprise that they comprise today. Finally, the review is also critical as we highlight problems, inconsistencies, and deviations from original intent in the various studies. (PsycINFO Database Record

Physical and Perceptual Independence of Ultrasonic Vibration and Electrovibration for Friction Modulation.

Two different principles are available to modulate the user perceived roughness of a surface: electrovibration and ultrasonic vibration of a plate. The former enhances the perceived friction coefficient and the latter reduces it. This paper will highlight the independence of the two effects on the physical and perceptual point of view to confirm the increased range of sensation and stimulation that can be supplied by the two coupled techniques to the users. Firstly, a tribometric analysis of the induced lateral force on the finger by the two coupled effects will be presented, then a study on the dynamic of the two effects will be reported. In the end, a psychophysical experiment on the perception of the two coupled techniques will be shown.

Modeling response times to analyze perceptual interactions in complex non-speech perception

General recognition theory (GRT) provides a powerful framework for modeling interactions between perceptual dimensions in identification-confusion data. The linear ballistic accumulator (LBA) model provides powerful methods for analyzing multi-choice (2 + ) response time (RT) data as a function of evidence accumulation and response thresholds. We extend (static) GRT to the domain of RTs by fitting LBA models to RTs collected in two auditory GRT experiments. Although the mapping between the constructs of GRT (e.g., perceptual separability, perceptual independence) and the components of the LBA (e.g., drift rates, response thresholds) is complex, the dimensional interactions defined in GRT can be indirectly addressed in the LBA framework by testing for invariance of LBA parameters across appropriate subsets of the data. The present work focuses on correspondences between (invariance of) parameters in LBA and perceptual separability and independence in GRT.

The Impacts of Inversion and Thatcherisation on Face Processing: Mapping between ERP and GRT

Prior work on the Thatcher illusion (Cornes et al., 2011; Mestry et al., 2012) has indicated both perceptual and decisional components of the illusion. We provide evidence of neural correlates associated with independent influences of inversion and level of feature manipulation (Thatcherisation) in the Thatcher illusion. We also provide an account of how ERP results can be interpreted within the configural processing framework defined by general recognition theory (GRT). We conducted a study examining inversion and the level of Thatcherisation (typical face, eyes Thatcherised, mouth Thatcherised, or both features Thatcherised) on a set of event-related components (the P1, N170, P2 and P3b) that have previously been considered in relation to the Thatcher illusion. Results reveal three independent effects: (1) inversion effects leading to increased amplitude for inverted faces at the N170 and P2 in the occipito-parietal area; (2) a reduction in N170 amplitude with level of Thatcherisation in the right hemisphere; and (3) inversion effects leading to increased amplitude for inverted faces at P3b in the centro-parietal area. This study reveals effects of Thatcherisation that are independent from effects of inversion in the ERP data. These effects can also be mapped to perceptual and decisional measures of configurality revealed in behavioural data using GRT (Mestry et al., 2012). We suggest the Thatcherisation effect at N170 may relate to violations of perceptual independence, the inversion effect across N170 and P2 may relate to violations of perceptual separability, and the inversion effect at P3b may relate to violations of decisional separability. Thus, we suggest a possible role for ERP data in providing a source of converging evidence for inferences regarding the role of perceptual and decisional factors in configurality.

Mutual information, perceptual independence, and holistic face perception

The concept of perceptual independence is ubiquitous in psychology. It addresses the question of whether two (or more) dimensions are perceived independently. Several authors have proposed perceptual independence (or its lack thereof) as a viable measure of holistic face perception (Loftus, Oberg, & Dillon, Psychological Review 111:835-863, 2004; Wenger & Ingvalson, Learning, Memory, and Cognition 28:872-892, 2002). According to this notion, the processing of facial features occurs in an interactive manner. Here, I examine this idea from the perspective of two theories of perceptual independence: the multivariate uncertainty analysis (MUA; Garner & Morton, Definitions, models, and experimental paradigms. Psychological Bulletin 72:233-259, 1969), and the general recognition theory (GRT; Ashby & Townsend, Psychological Review 93:154-179, 1986). The goals of the study were to (1) introduce the MUA, (2) examine various possible relations between MUA and GRT using numerical simulations, and (3) apply the MUA to two consensual markers of holistic face perception(-)recognition of facial features (Farah, Wilson, Drain, & Tanaka, Psychological Review 105:482-498, 1998) and the composite face effect (Young, Hellawell, & Hay, Perception 16:747-759, 1987). The results suggest that facial holism is generated by violations of several types of perceptual independence. They highlight the important theoretical role played by converging operations in the study of holistic face perception.

Variants of independence in the perception of facial identity and expression.

A prominent theory in the face perception literature--the parallel-route hypothesis (Bruce & Young, 1986)--assumes a dedicated channel for the processing of identity that is separate and independent from the channel(s) in which nonidentity information is processed (e.g., expression, eye gaze). The current work subjected this assumption to experimental tests from the perspective of three characterizations of independence and separability: Garner's speeded classification task (Garner, 1974), general recognition theory (Ashby & Townsend, 1986), and systems factorial technology (Townsend & Nozawa, 1995). The goals of the study were to (a) provide converging evidence on validity of the parallel-route hypothesis, and (b) understand the relationships between various definitions of independence and separability. The results of the current work demonstrated that identity and expression are not completely independent, using data from all three perspectives. Consequently, a modification of the central assumption of the parallel-route hypothesis is required. In addition, the intricate but orderly relationships between various types of separability and independence have implications for theories of perceptual independence.

General recognition theory extended to include response times: Predictions for a class of parallel systems

General Recognition Theory (GRT; Ashby & Townsend, 1986) is a multidimensional theory of classification. Originally developed to study various types of perceptual independence, it has also been widely employed in diverse cognitive venues, such as categorization. The initial theory and applications have been static, that is, lacking a time variable and focusing on patterns of responses, such as confusion matrices. Ashby proposed a parallel, dynamic stochastic version of GRT with application to perceptual independence based on discrete linear systems theory with imposed noise (Ashby, 1989). The current study again focuses on cognitive/perceptual independence within an identification classification paradigm. We extend stochastic GRT and its implicated methodology for cognitive/perceptual independence, to an entire class of parallel systems. This goal is met in a distribution-free manner and includes all linear and non-linear systems satisfying very general conditions. A number of theorems are proven concerning stochastic forms of independence. However, the theorems all assume the stochastic version of decisional separability. A vital task remains to investigate the consequences of failures of stochastic decisional separability.

Tests for Configural processing in the Thatcher Illusion

Thatcherisation of facial features is immediately apparent only in upright faces. Detection of Thatcherisation is therefore widely upheld as being dependent on configural processing. Configural processing has clear predictions of perceptual dependence between facial features and of supercapacity processing. Perceptual dependence: Configurality in General Recognition Theory (GRT, Ashby & Townsend, 1986) can be conceptualized in terms of violations of perceptual independence, in which the perceptions of the eyes and mouth of a single face are positively correlated; for example, the more inverted the eyes look, the more inverted the mouth will look. Participants were briefly presented with normal, partially Thatcherised and fully Thatcherised faces, and were asked to report whether the outline, eyes and mouth were upright or inverted. Consistent with the predictions, multi-dimensional probit models (DeCarlo, 2003) revealed that within-stimulus perceptual interactions occurred more frequently for upright than inverted faces. However, for the Thatcherised stimulus itself, there was no overall correlation between the eyes and the mouth, suggesting a lack of configural processing for this type of stimulus. Processing capacity: Supercapacity processing is predicted to accompany configural processing (O’Toole, Wenger & Townsend, 2001; Wenger & Townsend, 2001). Therefore, the detection of Thatcherised features in upright faces should be marked by supercapacity processing of inverted eyes and mouths relative to the inversion of only eyes or only mouths. Response times were used to compute measures of processing capacity (capacity coefficient, Townsend & Wenger, 2004; proportional hazards ratio, Wenger & Gibson, 2006) in Thatcherised upright faces. Results demonstrated limited evidence of supercapacity processing, and only in some individuals, implying that configural processing is not necessary for processing of upright Thatcherised faces. In summary, predictions from GRT and of processing capacity were tested across two separate studies, with little evidence found for perceptual independence or supercapacity processing for Thatcherised face stimuli.

Identifying Sources of Configurality in Three Face Processing Tasks

Participants performed three feature-complete face processing tasks involving detection of changes in: (1) feature size and (2) feature identity in successive matching tasks, and (3) feature orientation. In each experiment, information in the top (eyes) and bottom (mouths) parts of faces were manipulated. All tasks were performed with upright and inverted faces. Data were analyzed first using group-based analysis of signal detection measures (sensitivity and bias), and second using analysis of multidimensional measures of sensitivity and bias along with probit regression models in order to draw inferences about independence and separability as defined within general recognition theory (Ashby and Townsend, 1986). The results highlighted different patterns of perceptual and decisional influences across tasks and orientations. There was evidence of orientation specific configural effects (violations of perceptual independence, perceptual seperability and decisional separabilty) in the Feature Orientation Task. For the Feature Identity Task there were orientation specific performance effects and there was evidence of configural effects (violations of decisional separability) in both orientations. Decisional effects are consistent with previous research (Wenger and Ingvalson, 2002, 2003; Richler et al., 2008; Cornes et al., 2011). Crucially, the probit analysis revealed violations of perceptual independence that remain undetected by marginal analysis.

Perceptual and decisional factors influencing the discrimination of inversion in the Thatcher illusion.

The Thatcher illusion (Thompson, 1980) is considered to be a prototypical illustration of the notion that face perception is dependent on configural processes and representations. We explored this idea by examining the relative contributions of perceptual and decisional processes to the ability of observers to identify the orientation of two classes of forms-faces and churches-and a set of their component features. Observers were presented with upright and inverted images of faces and churches in which the components (eyes, mouth, windows, doors) were presented either upright or inverted. Observers first rated the subjective grotesqueness of all of the images and then performed a complete identification task in which they had to identify the orientation of the overall form and the orientation of each of the interior features. Grotesqueness ratings for both classes of image showed the standard modulation of rated grotesqueness as a function of orientation. The complete identification results revealed violations of both perceptual and decisional separability but failed to reveal any violations of within-stimulus (perceptual) independence. In addition, exploration of a simple bivariate Gaussian signal detection model of the relationship between identification performance and judged grotesqueness suggests that within-stimulus violations of perceptual independence on their own are insufficient for producing the illusion. This lack of evidence for within-stimulus configurality suggests the need for a critical reevaluation of the role of configural processing in the Thatcher illusion. (PsycINFO Database Record (c) 2011 APA, all rights reserved).