1
|
Keane BP, Paterno D, Kastner S, Krekelberg B, Silverstein SM. Intact illusory contour formation but equivalently impaired visual shape completion in first- and later-episode schizophrenia. JOURNAL OF ABNORMAL PSYCHOLOGY 2018; 128:57-68. [PMID: 30346202 DOI: 10.1037/abn0000384] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Visual shape completion is a fundamental process that constructs contours and shapes on the basis of the geometric relations between spatially separated edge elements. People with schizophrenia are impaired at distinguishing visually completed shapes, but when does the impairment emerge and how does it evolve with illness duration? The question bears on the debate as to whether cognition declines after illness onset. To address the issue, we tested healthy controls (n = 48), first-episode psychosis patients (n = 23), and chronic schizophrenia patients (n = 49) on a classic psychophysical task in which subjects discriminated the relative orientations of four sectored circles that either formed or did not form visually completed shapes (illusory and fragmented conditions, respectively). Visual shape completion was quantified as the extent to which performance in the illusory condition exceeded that of the fragmented. Half of the trials incorporated wire edge elements, which augment contour salience and improve shape completion. Each patient group exhibited large visual shape completion deficits that could not be explained by differences in age, motivation, or orientation tuning. Patients responded normally to changes in illusory contour salience, indicating that they were forming but not adequately employing such contours for discriminating shapes. Shape completion deficits were most apparent for patients with cognitive disorganization, poor premorbid early adolescent functioning, and normal orientation discrimination. Visual shape completion deficits emerge maximally by the first psychotic episode and arise from higher-level disturbances that are related to premorbid functioning and disorganization. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
Collapse
Affiliation(s)
- Brian P Keane
- Department of Psychiatry, Robert Wood Johnson Medical School, University Behavioral Health Care, Rutgers Biomedical and Health Sciences, Rutgers University
| | | | | | - Bart Krekelberg
- Center for Molecular and Behavioral Neuroscience, Rutgers University
| | - Steven M Silverstein
- Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University
| |
Collapse
|
2
|
Contour interpolation: A case study in Modularity of Mind. Cognition 2018; 174:1-18. [PMID: 29407601 DOI: 10.1016/j.cognition.2018.01.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 01/17/2018] [Accepted: 01/18/2018] [Indexed: 01/29/2023]
Abstract
In his monograph Modularity of Mind (1983), philosopher Jerry Fodor argued that mental architecture can be partly decomposed into computational organs termed modules, which were characterized as having nine co-occurring features such as automaticity, domain specificity, and informational encapsulation. Do modules exist? Debates thus far have been framed very generally with few, if any, detailed case studies. The topic is important because it has direct implications on current debates in cognitive science and because it potentially provides a viable framework from which to further understand and make hypotheses about the mind's structure and function. Here, the case is made for the modularity of contour interpolation, which is a perceptual process that represents non-visible edges on the basis of how surrounding visible edges are spatiotemporally configured. There is substantial evidence that interpolation is domain specific, mandatory, fast, and developmentally well-sequenced; that it produces representationally impoverished outputs; that it relies upon a relatively fixed neural architecture that can be selectively impaired; that it is encapsulated from belief and expectation; and that its inner workings cannot be fathomed through conscious introspection. Upon differentiating contour interpolation from a higher-order contour representational ability ("contour abstraction") and upon accommodating seemingly inconsistent experimental results, it is argued that interpolation is modular to the extent that the initiating conditions for interpolation are strong. As interpolated contours become more salient, the modularity features emerge. The empirical data, taken as a whole, show that at least certain parts of the mind are modularly organized.
Collapse
|
3
|
Nguyen J, Majmudar UV, Ravaliya JH, Papathomas TV, Torres EB. Automatically Characterizing Sensory-Motor Patterns Underlying Reach-to-Grasp Movements on a Physical Depth Inversion Illusion. Front Hum Neurosci 2016; 9:694. [PMID: 26779004 PMCID: PMC4700265 DOI: 10.3389/fnhum.2015.00694] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 12/07/2015] [Indexed: 11/25/2022] Open
Abstract
Recently, movement variability has been of great interest to motor control physiologists as it constitutes a physical, quantifiable form of sensory feedback to aid in planning, updating, and executing complex actions. In marked contrast, the psychological and psychiatric arenas mainly rely on verbal descriptions and interpretations of behavior via observation. Consequently, a large gap exists between the body's manifestations of mental states and their descriptions, creating a disembodied approach in the psychological and neural sciences: contributions of the peripheral nervous system to central control, executive functions, and decision-making processes are poorly understood. How do we shift from a psychological, theorizing approach to characterize complex behaviors more objectively? We introduce a novel, objective, statistical framework, and visuomotor control paradigm to help characterize the stochastic signatures of minute fluctuations in overt movements during a visuomotor task. We also quantify a new class of covert movements that spontaneously occur without instruction. These are largely beneath awareness, but inevitably present in all behaviors. The inclusion of these motions in our analyses introduces a new paradigm in sensory-motor integration. As it turns out, these movements, often overlooked as motor noise, contain valuable information that contributes to the emergence of different kinesthetic percepts. We apply these new methods to help better understand perception-action loops. To investigate how perceptual inputs affect reach behavior, we use a depth inversion illusion (DII): the same physical stimulus produces two distinct depth percepts that are nearly orthogonal, enabling a robust comparison of competing percepts. We find that the moment-by-moment empirically estimated motor output variability can inform us of the participants' perceptual states, detecting physiologically relevant signals from the peripheral nervous system that reveal internal mental states evoked by the bi-stable illusion. Our work proposes a new statistical platform to objectively separate changes in visual perception by quantifying the unfolding of movement, emphasizing the importance of including in the motion analyses all overt and covert aspects of motor behavior.
Collapse
Affiliation(s)
- Jillian Nguyen
- Graduate Program in Neuroscience, Rutgers University Piscataway, NJ, USA
| | - Ushma V Majmudar
- Department of Biomedical Engineering, Rutgers University Piscataway, NJ, USA
| | - Jay H Ravaliya
- Department of Biomedical Engineering, Rutgers University Piscataway, NJ, USA
| | - Thomas V Papathomas
- Graduate Program in Neuroscience, Rutgers UniversityPiscataway, NJ, USA; Department of Biomedical Engineering, Rutgers UniversityPiscataway, NJ, USA; Center for Cognitive Science, Rutgers UniversityPiscataway, NJ, USA
| | - Elizabeth B Torres
- Graduate Program in Neuroscience, Rutgers UniversityPiscataway, NJ, USA; Department of Biomedical Engineering, Rutgers UniversityPiscataway, NJ, USA; Center for Cognitive Science, Rutgers UniversityPiscataway, NJ, USA; Department of Psychology, Rutgers UniversityPiscataway, NJ, USA; Department of Computer Science, Rutgers UniversityPiscataway, NJ, USA
| |
Collapse
|
4
|
Joseph J, Gara MA, Silverstein SM. Hierarchical Classes Analysis (HICLAS): A novel data reduction method to examine associations between biallelic SNPs and perceptual organization phenotypes in schizophrenia. Schizophr Res Cogn 2015; 2:56-63. [PMID: 26346124 PMCID: PMC4559868 DOI: 10.1016/j.scog.2015.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The power of SNP association studies to detect valid relationships with clinical phenotypes in schizophrenia is largely limited by the number of SNPs selected and non-specificity of phenotypes. To address this, we first assessed performance on two visual perceptual organization tasks designed to avoid many generalized deficit confounds, Kanizsa shape perception and contour integration, in a schizophrenia patient sample. Then, to reduce the total number of candidate SNPs analyzed in association with perceptual organization phenotypes, we employed a two-stage strategy: first a priori SNPs from three candidate genes were selected (GAD1, NRG1 and DTNBP1); then a Hierarchical Classes Analysis (HICLAS) was performed to reduce the total number of SNPs, based on statistically related SNP clusters. HICLAS reduced the total number of candidate SNPs for subsequent phenotype association analyses from 6 to 3. MANCOVAs indicated that rs10503929 and rs1978340 were associated with the Kanizsa shape perception filling in metric but not the global shape detection metric. rs10503929 was also associated with altered contour integration performance. SNPs not selected by the HICLAS model were unrelated to perceptual phenotype indices. While the contribution of candidate SNPs to perceptual impairments requires further clarification, this study reports the first application of HICLAS as a hypothesis-independent mathematical method for SNP data reduction. HICLAS may be useful for future larger scale genotype-phenotype association studies.
Collapse
Affiliation(s)
- Jamie Joseph
- Rutgers University Graduate School of Biomedical Sciences, 675 Hoes Lane, Piscataway, NJ 08854, USA
- Rutgers University Behavioral Health Care, 151 Centennial Ave, Piscataway, NJ 08854, USA
| | - Michael A. Gara
- Rutgers University Behavioral Health Care, 151 Centennial Ave, Piscataway, NJ 08854, USA
- Rutgers–Robert Wood Johnson Medical School, 671 Hoes Lane, Piscataway, NJ 08854, USA
| | - Steven M. Silverstein
- Rutgers University Behavioral Health Care, 151 Centennial Ave, Piscataway, NJ 08854, USA
- Rutgers–Robert Wood Johnson Medical School, 671 Hoes Lane, Piscataway, NJ 08854, USA
- Corresponding author at: Department of Psychiatry, Rutgers University Behavioral Health Care and Robert Wood Johnson Medical School, 671 Hoes Lane, Piscataway, NJ 08854, USA.
| |
Collapse
|
5
|
Keane BP, Erlikhman G, Kastner S, Paterno D, Silverstein SM. Multiple forms of contour grouping deficits in schizophrenia: what is the role of spatial frequency? Neuropsychologia 2014; 65:221-33. [PMID: 25446968 PMCID: PMC4269227 DOI: 10.1016/j.neuropsychologia.2014.10.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/11/2014] [Accepted: 10/24/2014] [Indexed: 10/24/2022]
Abstract
Schizophrenia patients poorly perceive Kanizsa figures and integrate co-aligned contour elements (Gabors). They also poorly process low spatial frequencies (SFs), which presumably reflects dysfunction along the dorsal pathway. Can contour grouping deficits be explained in terms of the spatial frequency content of the display elements? To address the question, we tested patients and matched controls on three contour grouping paradigms in which the SF composition was modulated. In the Kanizsa task, subjects discriminated quartets of sectored circles ("pac-men") that either formed or did not form Kanizsa shapes (illusory and fragmented conditions, respectively). In contour integration, subjects identified the screen quadrant thought to contain a closed chain of co-circular Gabors. In collinear facilitation, subjects attempted to detect a central low-contrast element flanked by collinear or orthogonal high-contrast elements, and facilitation corresponded to the amount by which collinear flankers reduced contrast thresholds. We varied SF by modifying the element features in the Kanizsa task and by scaling the entire stimulus display in the remaining tasks (SFs ranging from 4 to 12 cycles/deg). Irrespective of SF, patients were worse at discriminating illusory, but not fragmented shapes. Contrary to our hypothesis, collinear facilitation and contour integration were abnormal in the clinical group only for the higher SF (>=10 c/deg). Grouping performance correlated with clinical variables, such as conceptual disorganization, general symptoms, and levels of functioning. In schizophrenia, three forms of contour grouping impairments prominently arise and cannot be attributed to poor low SF processing. Neurobiological and clinical implications are discussed.
Collapse
Affiliation(s)
- Brian P Keane
- University Behavioral Health Care, Rutgers University, Piscataway, NJ 08854, USA; Center for Cognitive Science, Rutgers University, Piscataway, NJ 08854, USA.
| | - Gennady Erlikhman
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Sabine Kastner
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08540, USA; Department of Psychology, Princeton University, Princeton, NJ 08540, USA
| | - Danielle Paterno
- University Behavioral Health Care, Rutgers University, Piscataway, NJ 08854, USA
| | - Steven M Silverstein
- University Behavioral Health Care, Rutgers University, Piscataway, NJ 08854, USA; Rutgers-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| |
Collapse
|
6
|
Keane BP, Joseph J, Silverstein SM. Late, not early, stages of Kanizsa shape perception are compromised in schizophrenia. Neuropsychologia 2014; 56:302-11. [PMID: 24513023 DOI: 10.1016/j.neuropsychologia.2014.02.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 01/28/2014] [Accepted: 02/02/2014] [Indexed: 11/17/2022]
Abstract
BACKGROUND Schizophrenia is a devastating psychiatric disorder characterized by symptoms including delusions, hallucinations, and disorganized thought. Kanizsa shape perception is a basic visual process that builds illusory contour and shape representations from spatially segregated edges. Recent studies have shown that schizophrenia patients exhibit abnormal electrophysiological signatures during Kanizsa shape perception tasks, but it remains unclear how these abnormalities are manifested behaviorally and whether they arise from early or late levels in visual processing. METHOD To address this issue, we had healthy controls and schizophrenia patients discriminate quartets of sectored circles that either formed or did not form illusory shapes (illusory and fragmented conditions, respectively). Half of the trials in each condition incorporated distractor lines, which are known to disrupt illusory contour formation and thereby worsen illusory shape discrimination. RESULTS Relative to their respective fragmented conditions, patients performed worse than controls in the illusory discrimination. Conceptually disorganized patients-characterized by their incoherent manner of speaking-were primarily driving the effect. Regardless of patient status or disorganization levels, distractor lines worsened discrimination more in the illusory than the fragmented condition, indicating that all groups could form illusory contours. CONCLUSION People with schizophrenia form illusory contours but are less able to utilize those contours to discern global shape. The impairment is especially related to the ability to think and speak coherently. These results suggest that Kanizsa shape perception incorporates an early illusory contour formation stage and a later, conceptually-mediated shape integration stage, with the latter being compromised in schizophrenia.
Collapse
Affiliation(s)
- Brian P Keane
- Rutgers - Robert Wood Johnson Medical School, 671 Hoes Lane, Piscataway, NJ 08854, USA; Rutgers University Behavioral Health Care, 151 Centennial Ave, Piscataway, NJ 08854, USA; Rutgers University Center for Cognitive Science, 152 Frelinghuysen Road, Piscataway, NJ 08854-8020, USA.
| | - Jamie Joseph
- Rutgers University Behavioral Health Care, 151 Centennial Ave, Piscataway, NJ 08854, USA; Rutgers University Graduate School of Biomedical Sciences, Piscataway, NJ 08854, USA
| | - Steven M Silverstein
- Rutgers - Robert Wood Johnson Medical School, 671 Hoes Lane, Piscataway, NJ 08854, USA; Rutgers University Behavioral Health Care, 151 Centennial Ave, Piscataway, NJ 08854, USA
| |
Collapse
|
7
|
Keane BP, Lu H, Papathomas TV, Silverstein SM, Kellman PJ. Is interpolation cognitively encapsulated? Measuring the effects of belief on Kanizsa shape discrimination and illusory contour formation. Cognition 2012; 123:404-18. [PMID: 22440789 PMCID: PMC3548673 DOI: 10.1016/j.cognition.2012.02.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 02/08/2012] [Accepted: 02/11/2012] [Indexed: 11/18/2022]
Abstract
Contour interpolation is a perceptual process that fills-in missing edges on the basis of how surrounding edges (inducers) are spatiotemporally related. Cognitive encapsulation refers to the degree to which perceptual mechanisms act in isolation from beliefs, expectations, and utilities (Pylyshyn, 1999). Is interpolation encapsulated from belief? We addressed this question by having subjects discriminate briefly-presented, partially-visible fat and thin shapes, the edges of which either induced or did not induce illusory contours (relatable and non-relatable conditions, respectively). Half the trials in each condition incorporated task-irrelevant distractor lines, known to disrupt the filling-in of contours. Half of the observers were told that the visible parts of the shape belonged to a single thing (group strategy); the other half were told that the visible parts were disconnected (ungroup strategy). It was found that distractor lines strongly impaired performance in the relatable condition, but minimally in the non-relatable condition; that strategy did not alter the effects of the distractor lines for either the relatable or non-relatable stimuli; and that cognitively grouping relatable fragments improved performance whereas cognitively grouping non-relatable fragments did not. These results suggest that (1) filling-in effects during illusory contour formation cannot be easily removed via strategy; (2) filling-in effects cannot be easily manufactured from stimuli that fail to elicit interpolation; and (3) actively grouping fragments can readily improve discrimination performance, but only when those fragments form interpolated contours. Taken together, these findings indicate that discriminating filled-in shapes depends on strategy but the filling-in process itself may be encapsulated from belief.
Collapse
Affiliation(s)
- Brian P Keane
- Department of Psychology, University of California, Los Angeles, USA.
| | | | | | | | | |
Collapse
|