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Budson AE, Richman KA, Kensinger EA. Consciousness as a Memory System. Cogn Behav Neurol 2022; 35:263-297. [PMID: 36178498 PMCID: PMC9708083 DOI: 10.1097/wnn.0000000000000319] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/03/2022] [Indexed: 01/31/2023]
Abstract
We suggest that there is confusion between why consciousness developed and what additional functions, through continued evolution, it has co-opted. Consider episodic memory. If we believe that episodic memory evolved solely to accurately represent past events, it seems like a terrible system-prone to forgetting and false memories. However, if we believe that episodic memory developed to flexibly and creatively combine and rearrange memories of prior events in order to plan for the future, then it is quite a good system. We argue that consciousness originally developed as part of the episodic memory system-quite likely the part needed to accomplish that flexible recombining of information. We posit further that consciousness was subsequently co-opted to produce other functions that are not directly relevant to memory per se, such as problem-solving, abstract thinking, and language. We suggest that this theory is compatible with many phenomena, such as the slow speed and the after-the-fact order of consciousness, that cannot be explained well by other theories. We believe that our theory may have profound implications for understanding intentional action and consciousness in general. Moreover, we suggest that episodic memory and its associated memory systems of sensory, working, and semantic memory as a whole ought to be considered together as the conscious memory system in that they, together, give rise to the phenomenon of consciousness. Lastly, we suggest that the cerebral cortex is the part of the brain that makes consciousness possible, and that every cortical region contributes to this conscious memory system.
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Affiliation(s)
- Andrew E. Budson
- Center for Translational Cognitive Neuroscience, Veterans Affairs Boston Healthcare System, Boston, Massachusetts
- Alzheimer’s Disease Research Center, Boston University, Boston, Massachusetts
| | - Kenneth A. Richman
- Center for Health Humanities, Massachusetts College of Pharmacy and Health Sciences, Boston, Massachusetts
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2
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Kozuch B. Conscious vision guides motor action—rarely. PHILOSOPHICAL PSYCHOLOGY 2022. [DOI: 10.1080/09515089.2022.2044461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Benjamin Kozuch
- Philosophy Department, University of Alabama, Tuscaloosa, Alabama, USA
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3
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Ferretti G. A distinction concerning vision-for-action and affordance perception. Conscious Cogn 2021; 87:103028. [PMID: 33412389 DOI: 10.1016/j.concog.2020.103028] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 07/27/2020] [Accepted: 09/26/2020] [Indexed: 01/03/2023]
Abstract
In this paper, I offer a discussion concerning the conceptual connection between the notion of vision-for-action and the one of affordance perception. I first analyze the notion of vision-for-action. I then analyze a notion usually coupled with it: the notion of affordance perception, the main insights behind which are guiding several current neuroscientific enterprises and the related philosophical speculations. Then, I argue that we should not couple these two notions with a light heart: though these two processes can be, from a theoretical point of view, related, we should be careful in inferring the actual and effective occurrence of the latter in the presence of the former. This will be done by carrying out a conceptual analysis of the experimental evidence coming from the 'Two Visual Systems Model', which is the main reference in the literature on affordance perception and vision-for-action. My point has strong philosophical implications for our view concerning the best interpretation of how vision-for-action really works, and the specific relation it actually entertains with affordance perception.
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Affiliation(s)
- Gabriele Ferretti
- Eikones - Center for the Theory and History of the Image, University of Basel, Rheinsprung 11, 4051 Basel, Switzerland; Institute for Philosophy II, Ruhr-University Bochum, GA 3/151, Universitätsstr. 150, 44780 Bochum, Germany.
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4
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Thulasiram MR, Langridge RW, Abbas HH, Marotta JJ. Eye-hand coordination in reaching and grasping vertically moving targets. Exp Brain Res 2020; 238:1433-1440. [PMID: 32382863 DOI: 10.1007/s00221-020-05826-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 04/28/2020] [Indexed: 01/14/2023]
Abstract
Previous investigations have uncovered a strong visual bias toward the index finger when reaching and grasping stationary or horizontally moving targets. The present research sought to explore whether the index finger or thumb would serve as a significant focus for gaze in tasks involving vertically translating targets. Participants executed right-handed reach-to-grasp movements towards upward or downward moving 2-D targets on a computer screen. When the target first appeared, participants made anticipatory fixations in the direction of the eventual movement path (i.e. well above upwardly moving targets or well below downwardly moving targets) and upon movement onset, fixations shifted toward the leading edge of the target. For upward moving targets, fixations remained toward the leading edge upon reach onset, whereas for downward moving targets, fixations shifted toward the centre of the target. The same central fixation location was observed at the time of grasp for all targets. Furthermore, for downwardly moving targets, the placement of the thumb appears to have influenced fixation location in conjunction with, not replacement of, the influence of the index finger. These findings are indicative of the increasingly relevant role of the thumb in mediating reaching and grasping downwardly moving targets.
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Affiliation(s)
- Matsya R Thulasiram
- Perception and Action Lab, Department of Psychology, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada.
| | - Ryan W Langridge
- Perception and Action Lab, Department of Psychology, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada
| | - Hana H Abbas
- Perception and Action Lab, Department of Psychology, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada
| | - Jonathan J Marotta
- Perception and Action Lab, Department of Psychology, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada
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5
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Mylopoulos M, Pacherie E. Intentions: The dynamic hierarchical model revisited. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2018; 10:e1481. [PMID: 30105894 DOI: 10.1002/wcs.1481] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 07/04/2018] [Accepted: 07/22/2018] [Indexed: 01/01/2023]
Abstract
Ten years ago, one of us proposed a dynamic hierarchical model of intentions that brought together philosophical work on intentions and empirical work on motor representations and motor control (Pacherie, 2008). The model distinguished among Distal intentions, Proximal intentions, and Motor intentions operating at different levels of action control (hence the name DPM model). This model specified the representational and functional profiles of each type of intention, as well their local and global dynamics, and the ways in which they interact. A core insight of the model was that action control is the result of integrated, coordinated activity across these levels of intention. Since the proposal of the model, empirical and theoretical works in philosophy and cognitive science have emerged that would seem to support and expand on this central insight. In particular, an updated understanding of the nature of sensorimotor processing and motor representations, as well as of how the different levels of intention and control interface and interact, allows for the further specification and precisification of the original DPM model. This article is categorized under: Philosophy > Psychological Capacities Psychology > Motor Skill and Performance Philosophy > Action.
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Affiliation(s)
- Myrto Mylopoulos
- Department of Philosophy and Institute of Cognitive Science, Carleton University, Ottawa, Ontario, Canada
| | - Elisabeth Pacherie
- Institut Jean Nicod, Département d'études cognitives, ENS, EHESS, CNRS, PSL Research University, Paris, France
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6
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Cecchi AS. Cognitive penetration of early vision in face perception. Conscious Cogn 2018; 63:254-266. [PMID: 29909046 DOI: 10.1016/j.concog.2018.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 05/01/2018] [Accepted: 06/05/2018] [Indexed: 11/16/2022]
Abstract
Cognitive and affective penetration of perception refers to the influence that higher mental states such as beliefs and emotions have on perceptual systems. Psychological and neuroscientific studies appear to show that these states modulate the visual system at the visuomotor, attentional, and late levels of processing. However, empirical evidence showing that similar consequences occur in early stages of visual processing seems to be scarce. In this paper, I argue that psychological evidence does not seem to be either sufficient or necessary to argue in favour of or against the cognitive penetration of perception in either late or early vision. In order to do that we need to have recourse to brain imaging techniques. Thus, I introduce a neuroscientific study and argue that it seems to provide well-grounded evidence for the cognitive penetration of early vision in face perception. I also examine and reject alternative explanations to my conclusion.
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Affiliation(s)
- Ariel S Cecchi
- Department of Experimental Psychology, University College London, United Kingdom; Centre for Philosophy of Natural and Social Science, London School of Economics and Political Science, United Kingdom.
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7
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Borsook D, Youssef AM, Barakat N, Sieberg CB, Elman I. Subliminal (latent) processing of pain and its evolution to conscious awareness. Neurosci Biobehav Rev 2018; 88:1-15. [PMID: 29476771 DOI: 10.1016/j.neubiorev.2018.02.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/07/2018] [Accepted: 02/19/2018] [Indexed: 12/18/2022]
Abstract
By unconscious or covert processing of pain we refer to nascent interactions that affect the eventual deliverance of pain awareness. Thus, internal processes (viz., repeated nociceptive events, inflammatory kindling, reorganization of brain networks, genetic) or external processes (viz., environment, socioeconomic levels, modulation of epigenetic status) contribute to enhancing or inhibiting the presentation of pain awareness. Here we put forward the notion that for many patients, ongoing sub-conscious changes in brain function are significant players in the eventual manifestation of chronic pain. In this review, we provide clinical examples of nascent or what we term pre-pain processes and the neurobiological mechanisms of how these changes may contribute to pain, but also potential opportunities to define the process for early therapeutic interventions.
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Affiliation(s)
- David Borsook
- Center for Pain and the Brain, 9 Hope Avenue, Mailbox 26, Waltham, MA, 06524-9936, United States.
| | - Andrew M Youssef
- Center for Pain and the Brain, 9 Hope Avenue, Mailbox 26, Waltham, MA, 06524-9936, United States
| | - Nadia Barakat
- Center for Pain and the Brain, 9 Hope Avenue, Mailbox 26, Waltham, MA, 06524-9936, United States
| | - Christine B Sieberg
- Center for Pain and the Brain, 9 Hope Avenue, Mailbox 26, Waltham, MA, 06524-9936, United States
| | - Igor Elman
- Dayton Veterans Affairs Medical Center 4100 West Third Street Dayton, OH, 45428, United States
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8
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Brogaard B, Gatzia DE. Unconscious Imagination and the Mental Imagery Debate. Front Psychol 2017; 8:799. [PMID: 28588527 PMCID: PMC5440590 DOI: 10.3389/fpsyg.2017.00799] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/02/2017] [Indexed: 11/13/2022] Open
Abstract
Traditionally, philosophers have appealed to the phenomenological similarity between visual experience and visual imagery to support the hypothesis that there is significant overlap between the perceptual and imaginative domains. The current evidence, however, is inconclusive: while evidence from transcranial brain stimulation seems to support this conclusion, neurophysiological evidence from brain lesion studies (e.g., from patients with brain lesions resulting in a loss of mental imagery but not a corresponding loss of perception and vice versa) indicates that there are functional and anatomical dissociations between mental imagery and perception. Assuming that the mental imagery and perception do not overlap, at least, to the extent traditionally assumed, then the question arises as to what exactly mental imagery is and whether it parallels perception by proceeding via several functionally distinct mechanisms. In this review, we argue that even though there may not be a shared mechanism underlying vision for perception and conscious imagery, there is an overlap between the mechanisms underlying vision for action and unconscious visual imagery. On the basis of these findings, we propose a modification of Kosslyn's model of imagery that accommodates unconscious imagination and explore possible explanations of the quasi-pictorial phenomenology of conscious visual imagery in light of the fact that its underlying neural substrates and mechanisms typically are distinct from those of visual experience.
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Affiliation(s)
- Berit Brogaard
- The Brogaard Lab for Multisensory Research, University of Miami, MiamiFL, United States.,Department of Philosophy, University of OsloOslo, Norway
| | - Dimitria Electra Gatzia
- Department of Philosophy, University of Akron Wayne College, AkronOH, United States.,Centre for Philosophical Psychology, University of AntwerpAntwerp, Belgium
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9
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Brogaard B, Marlow K, Overgaard M, Schwartz BL, Zopluoglu C, Tomson S, Neufed J, Sinke C, Owen C, Eagleman D. Deaf hearing: Implicit discrimination of auditory content in a patient with mixed hearing loss. PHILOSOPHICAL PSYCHOLOGY 2017. [DOI: 10.1080/09515089.2016.1268680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Berit Brogaard
- Brogaard Lab for Multisensory Research, University of Miami, Miami, FL, USA
- Department of Philosophy, University of Oslo, Oslo, Norway
| | - Kristian Marlow
- Brogaard Lab for Multisensory Research, University of Miami, Miami, FL, USA
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Morten Overgaard
- Cognitive Science Research Unit, CFIN/MindLab, Aarhus University, Aarhus, Denmark
| | | | - Cengiz Zopluoglu
- Department of Educational and Psychological Studies, University of Miami, Miami, FL, USA
| | - Steffie Tomson
- Psychiatry and Biobehavioral Sciences Department, University of California Los Angeles, Los Angeles, CA, USA
| | - Janina Neufed
- Pediatric Neuropsychiatry Unit, Department of Women’s and Children’s Health, Center of Neurodevelopmental Disorders (KIIND), Karolinska Institutet, Stockholm, Sweden
- Clinic for Psychiatry, Social Psychiatry, and Psychotherapy, Hannover Medical School, Hannover, Germany
| | - Christopher Sinke
- Clinic for Psychiatry, Social Psychiatry, and Psychotherapy, Hannover Medical School, Hannover, Germany
| | - Christopher Owen
- Brogaard Lab for Multisensory Research, University of Miami, Miami, FL, USA
- NeuroImaging Lab, Washington University Medical School, St. Louis, MO, USA
| | - David Eagleman
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA, USA
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10
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Semantic and pragmatic integration in vision for action. Conscious Cogn 2017; 48:40-54. [DOI: 10.1016/j.concog.2016.10.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 10/10/2016] [Accepted: 10/23/2016] [Indexed: 11/18/2022]
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11
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Brogaard B, Gatzia DE. Is Color Experience Cognitively Penetrable? Top Cogn Sci 2016; 9:193-214. [PMID: 27797145 DOI: 10.1111/tops.12221] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 01/30/2015] [Accepted: 07/24/2016] [Indexed: 12/01/2022]
Abstract
Is color experience cognitively penetrable? Some philosophers have recently argued that it is. In this paper, we take issue with the claim that color experience is cognitively penetrable. We argue that the notion of cognitive penetration that has recently dominated the literature is flawed since it fails to distinguish between the modulation of perceptual content by non-perceptual principles and genuine cognitive penetration. We use this distinction to show that studies suggesting that color experience can be modulated by factors of the cognitive system do not establish that color experience is cognitively penetrable. Additionally, we argue that even if color experience turns out to be modulated by color-related beliefs and knowledge beyond non-perceptual principles, it does not follow that color experience is cognitively penetrable since the experiences of determinate hues involve post-perceptual processes. We conclude with a brief discussion of the implications that these ideas may have on debates in philosophy.
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12
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Ferretti G. Through the forest of motor representations. Conscious Cogn 2016; 43:177-96. [PMID: 27310110 DOI: 10.1016/j.concog.2016.05.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 05/26/2016] [Accepted: 05/30/2016] [Indexed: 10/21/2022]
Abstract
Following neuroscience, and using different labels, several philosophers have addressed the idea of the presence of a single representational mechanism lying in between (visual) perceptual processes and motor processes involved in different functions and useful for shaping suitable action performances: a motor representation (MR). MRs are the naturalized mental antecedents of action. This paper presents a new, non-monolithic view of MRs, according to which, contrarily to the received view, when looking at in between (visual) perceptual processes and motor processes, we find not only a single representational mechanism with different functions, but an ensemble of different sub-representational phenomena, each of which with a different function. This new view is able to avoid several issues emerging from the literature and to address something the literature is silent about, which however turns out to be crucial for a theory of MRs.
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Affiliation(s)
- Gabriele Ferretti
- Department of Pure and Applied Science, University of Urbino Carlo Bo, Via Timoteo Viti, 10, 61029 Urbino, PU, Italy; Centre for Philosophical Psychology, University of Antwerp, S.S. 208, Lange Sint Annastraat 7, 2000 Antwerpen, Belgium.
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13
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Abstract
I argue that the neural realizers of experiences of trying (that is, experiences of directing effort towards the satisfaction of an intention) are not distinct from the neural realizers of actual trying (that is, actual effort directed towards the satisfaction of an intention). I then ask how experiences of trying might relate to the perceptual experiences one has while acting. First, I assess recent zombie action arguments regarding conscious visual experience, and I argue that contrary to what some have claimed, conscious visual experience plays a causal role for action control in some circumstances. Second, I propose a multimodal account of the experience of acting. According to this account, the experience of acting is (at the very least) a temporally extended, co-conscious collection of agentive and perceptual experiences, functionally integrated and structured both by multimodal perceptual processing as well as by what an agent is, at the time, trying to do.
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Abstract
The extensive involvement of nonconscious processes in human behaviour has led some to suggest that consciousness is much less important for the control of action than we might think. In this article I push against this trend, developing an understanding of conscious control that is sensitive to our best models of overt (that is, bodily) action control. Further, I assess the cogency of various zombie challenges-challenges that seek to demote the importance of conscious control for human agency. I argue that though nonconscious contributions to action control are evidently robust, these challenges are overblown.
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Affiliation(s)
- Joshua Shepherd
- Faculty of Philosophy, Oxford Centre for Neuroethics, University of Oxford
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15
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Foley R. The case for characterising type-2 blindsight as a genuinely visual phenomenon. Conscious Cogn 2014; 32:56-67. [PMID: 25444645 DOI: 10.1016/j.concog.2014.09.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 09/08/2014] [Accepted: 09/12/2014] [Indexed: 11/25/2022]
Abstract
Type-2 blindsight is often characterised as involving a non-visual form of awareness that blindsight subjects experience under certain presentation conditions. This paper evaluates the claim that type-2 awareness is non-visual and the proposal that it is a cognitive form of awareness. It is argued that, contrary to the standard account, type-2 awareness is best characterised as visual both because it satisfies certain criteria for being visual and because it can accommodate facts about the phenomenon that the cognitive account cannot. The conclusion is made that type-2 blindsight is best characterised as involving a form of abnormal, degraded visual awareness.
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Affiliation(s)
- Robert Foley
- The Rotman Institute, Western University, Stevenson Hall 2150G, London, Ontario N6A 5B8, Canada.
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16
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Abstract
Newell & Shanks (N&S) argue that an explanation for blindsight need not appeal to unconscious brain processes, citing research indicating that the condition merely reflects degraded visual experience. We reply that other evidence suggests blindsighters' predictive behavior under forced choice reflects cognitive access to low-level visual information that does not correlate with visual consciousness. Therefore, while we grant that visual consciousness may be required for full visual experience, we argue that it may not be needed for decision making and judgment.
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Decoupled visually-guided reaching in optic ataxia: differences in motor control between canonical and non-canonical orientations in space. PLoS One 2013; 8:e86138. [PMID: 24392035 PMCID: PMC3877394 DOI: 10.1371/journal.pone.0086138] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 12/05/2013] [Indexed: 11/25/2022] Open
Abstract
Guiding a limb often involves situations in which the spatial location of the target for gaze and limb movement are not congruent (i.e. have been decoupled). Such decoupled situations involve both the implementation of a cognitive rule (i.e. strategic control) and the online monitoring of the limb position relative to gaze and target (i.e. sensorimotor recalibration). To further understand the neural mechanisms underlying these different types of visuomotor control, we tested patient IG who has bilateral caudal superior parietal lobule (SPL) damage resulting in optic ataxia (OA), and compared her performance with six age-matched controls on a series of center-out reaching tasks. The tasks comprised 1) directing a cursor that had been rotated (180° or 90°) within the same spatial plane as the visual display, or 2) moving the hand along a different spatial plane than the visual display (horizontal or para-sagittal). Importantly, all conditions were performed towards visual targets located along either the horizontal axis (left and right; which can be guided from strategic control) or the diagonal axes (top-left and top-right; which require on-line trajectory elaboration and updating by sensorimotor recalibration). The bilateral OA patient performed much better in decoupled visuomotor control towards the horizontal targets, a canonical situation in which well-categorized allocentric cues could be utilized (i.e. guiding cursor direction perpendicular to computer monitor border). Relative to neurologically intact adults, IG's performance suffered towards diagonal targets, a non-canonical situation in which only less-categorized allocentric cues were available (i.e. guiding cursor direction at an off-axis angle to computer monitor border), and she was therefore required to rely on sensorimotor recalibration of her decoupled limb. We propose that an intact caudal SPL is crucial for any decoupled visuomotor control, particularly when relying on the realignment between vision and proprioception without reliable allocentric cues towards non-canonical orientations in space.
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Bringoux L, Lepecq JC, Danion F. Does visually induced self-motion affect grip force when holding an object? J Neurophysiol 2012; 108:1685-94. [PMID: 22723677 DOI: 10.1152/jn.00407.2012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Accurate control of grip force during object manipulation is necessary to prevent the object from slipping, especially to compensate for the action of gravitational and inertial forces resulting from hand/object motion. The goal of the current study was to assess whether the control of grip force was influenced by visually induced self-motion (i.e., vection), which would normally be accompanied by changes in object load. The main task involved holding a 400-g object between the thumb and the index finger while being seated within a virtual immersive environment that simulated the vertical motion of an elevator across floors. Different visual motions were tested, including oscillatory (0.21 Hz) and constant-speed displacements of the virtual scene. Different arm-loading conditions were also tested: with or without the hand-held object and with or without oscillatory arm motion (0.9 Hz). At the perceptual level, ratings from participants showed that both oscillatory and constant-speed motion of the elevator rapidly induced a long-lasting sensation of self-motion. At the sensorimotor level, vection compellingness altered arm movement control. Spectral analyses revealed that arm motion was entrained by the oscillatory motion of the elevator. However, we found no evidence that grip force used to hold the object was visually affected. Specifically, spectral analyses revealed no component in grip force that would mirror the virtual change in object load associated with the oscillatory motion of the elevator, thereby allowing the grip-to-load force coupling to remain unaffected. Altogether, our findings show that the neural mechanisms underlying vection interfere with arm movement control but do not interfere with the delicate modulation of grip force. More generally, those results provide evidence that the strength of the coupling between the sensorimotor system and the perceptual level can be modulated depending on the effector.
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Affiliation(s)
- Lionel Bringoux
- Institute of Movement Sciences, Aix-Marseille University and Centre National de la Recherche Scientifique, Marseille, France
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19
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Brogaard B. Non-visual consciousness and visual images in blindsight. Conscious Cogn 2012; 21:595-6. [DOI: 10.1016/j.concog.2011.12.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 12/11/2011] [Indexed: 11/26/2022]
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