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Conscious and unconscious vision
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This thesis is about conscious and unconscious vision. When somebody enters an elevator, the electronic eye at the entrance of the door takes notice and prevents the door from closing. However, no one will seriously claim that an elevator has the same sensation as our own when you see somebody come in. What makes us conscious of the things we see? What brain processes are responsible for conscious perception? And what brain processes have nothing to do with consciousness and are more similar to the way electronic eyes process visual information? The aim of this thesis is to begin to answer questions like these.
Descartes’ dualism is often mentioned in jest, and although Descartes is probably most known for the notion of dualism, he is actually one of the founding fathers of the way we look at the relationship between mind and body today: the human body as a machine in ‘Traité de l’homme’. In this book, Descartes introduces the concept of a ‘reflex’: an involuntary movement that is executed directly, without intervention by the conscious mind. Reflexes are obviously mechanistic and it is clear how they come about. How the conscious mind comes about is less clear.
As the brain processes visual information, it initially responds as in a reflex: fast, automatically and unconsciously. This initial reflex- like process is known as the Fast Feedforward Sweep (FFS). In this thesis, I defend the position that the FFS supports functions that have previously been associated with consciousness, such as the detection and categorization of objects. Experiments in this thesis show that the brain is able to detect and categorize objects without a person becoming conscious of these objects. Furthermore, I attempt to prove that the processes responsible for conscious perception only emerge after the FFS, in what is referred to as feedback or Recurrent Processing (RP). RP is the stream of processing through which early visual areas are reactivated, making use of nerve pathways that flow back from higher to lower visual areas. I show that this reactivation as a result of RP is what causes visual consciousness.
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... Most research in the field of psychology and medicine analyzes the mechanisms of consciousness and the unconscious when analyzing or solving practical problems, such as the learning process (Cleremans, 2014). Another portion of the research analyzes a person's behavior and his reaction to the presentation of individual stimuli (Eimer, 2002;Fahrenfort, 2009;Railo, 2012). Starting with the classic work of Darwin Dimberg, 2000;Janssen, 2009), much research has been devoted to the study of conscious and unconscious reactions' influence on the facial expressions of people demonstrating aggressive and depressive behavior. ...
VIBRA2019 conference proceedings from 27 papers presented at the 2nd International Open Science Conference “Modern Psychophysiology. The Vibraimage Technology” by scientists and specialists from Russia, Japan, China, Korea and the EU. The study of behavioral and mental processes using vibraimage technology in the fields of psychophysiology, physiology, medicine, psychology (general, social, sports, clinical) are discussed. The results of research and the use of vibraimage technology in practical areas are presented (safety, psychophysiological detection of deception, pre-shift psychophysiological control, control of the current psychophysiological state of an operator, sports, HR, vocational guidance, recruiting, determination of abilities and multiple intelligences in adults and children). The errors, accuracy, and algorithms for obtaining vibraimages are investigated. The absence of a correlation between the conscious and unconscious response of a person to stimuli is established. The hypothesis of the additive characteristics of personality and substantiated using additive parameters of consciousness and the unconscious was proposed. The concept of chronobiological rhythm of brain activity and the period of brain activity as function from the load on the brain are investigated. The influence of various stimuli on the psychophysiological state of a person are studied. The changes in a person’s psychophysiological state with a changing intensity of mental and physical activity are analyzed, taking into account the profile of their main activities and different ethnicities. These studies of psychophysiological parameters were carried out using well-known vibraimage programs (Vibraimage PRO, VibraMed, VibraStaff, VibraMI, PsyAccent) as well as new vibraimage programs and methods (PsyComfort, VibraSport, WelcomEU).
We investigated the cortical mechanisms of visual-spatial attention while subjects discriminated patterned targets within distractor arrays. Functional magnetic resonance imaging (fMRI) was used to map the boundaries of retinotopic visual areas and to localize attention-related changes in neural activity within several of those areas, including primary visual (striate) cortex. Event-related potentials (ERPs) and modeling of their neural sources, however, indicated that the initial sensory input to striate cortex at 50−55 milliseconds after the stimulus was not modulated by attention. The earliest facilitation of attended signals was observed in extrastriate visual areas, at 70−75 milliseconds. We hypothesize that the striate cortex modulation found with fMRI may represent a delayed, re-entrant feedback from higher visual areas or a sustained biasing of striate cortical neurons during attention. ERP recordings provide critical temporal information for analyzing the functional neuroanatomy of visual attention.
To make progress on the problem of consciousness, we have to confront it directly. In this paper, I first isolate the truly hard part of the problem, separating it from more tractable parts and giving an account of why it is so difficult to explain. I critique some recent work that uses reductive methods to address consciousness, and argue that these methods inevitably fail to come to grips with the hardest part of the problem. Once this failure is recognized, the door to further progress is opened. In the second half of the paper, I argue that if we move to a new kind of nonreductive explanation, a naturalistic account of consciousness can be given. I put forward my own candidate for such an account: a nonreductive theory based on principles of structural coherence and organizational invariance and a double-aspect view of information.
In recent years, many new cortical areas have been identified in the macaque monkey. The number of identified connections between areas has increased even more dramatically. We report here on (1) a summary of the layout of cortical areas associated with vision and with other modalities, (2) a computerized database for storing and representing large amounts of information on connectivity patterns, and (3) the application of these data to the analysis of hierarchical organization of the cerebral cortex. Our analysis concentrates on the visual system, which includes 25 neocortical areas that are predominantly or exclusively visual in function, plus an additional 7 areas that we regard as visual-association areas on the basis of their extensive visual inputs. A total of 305 connections among these 32 visual and visual-association areas have been reported. This represents 31% of the possible number of pathways it each area were connected with all others. The actual degree of connectivity is likely to be closer to 40%. The great majority of pathways involve reciprocal connections between areas. There are also extensive connections with cortical areas outside the visual system proper, including the somatosensory cortex, as well as neocortical, transitional, and archicortical regions in the temporal and frontal lobes. In the somatosensory/motor system, there are 62 identified pathways linking 13 cortical areas, suggesting an overall connectivity of about 40%. Based on the laminar patterns of connections between areas, we propose a hierarchy of visual areas and of somato sensory/motor areas that is more comprehensive than those suggested in other recent studies. The current version of the visual hierarchy includes 10 levels of cortical processing. Altogether, it contains 14 levels if one includes the retina and lateral geniculate nucleus at the bottom as well as the entorhinal cortex and hippocampus at the top. Within this hierarchy, there are multiple, intertwined processing streams, which, at a low level, are related to the compartmental organization of areas V1 and V2 and, at a high level, are related to the distinction between processing centers in the temporal and parietal lobes. However, there are some pathways and relationships (about 10% of the total) whose descriptions do not fit cleanly into this hierarchical scheme for one reason or another. In most instances, though, it is unclear whether these represent genuine exceptions to a strict hierarchy rather than inaccuracies or uncertainties in the reported assignment.
Correction for ‘Spatial attention and neglect: parietal, frontal and cingulate contributions to the mental representation and attentional targeting of salient extrapersonal events’ by M.-M. Mesulam (Phil. Trans. R. Soc. Lond. B 354 , 1325–1346. (doi: [10.1098/rstb.1999.0482][1])).
In the legend to figure 3 (p. 1332), the words left and right were mistakenly transposed.
[1]: /lookup/doi/10.1098/rstb.1999.0482