Cortical processing and perceived timing

As of yet, it is unclear how we determine relative perceived timing. One controversial suggestion is that timing perception might be related to when analyses are completed in the cortex of the brain. An alternate proposal suggests that perceived timing is instead related to the point in time at which cortical analyses commence. Accordingly, timing illusions should not occur owing to cortical analyses, but they could occur if there were differential delays between signals reaching cortex. Resolution of this controversy therefore requires that the contributions of cortical processing be isolated from the influence of subcortical activity. Here, we have done this by using binocular disparity changes, which are known to be detected via analyses that originate in cortex. We find that observers require longer stimulus exposures to detect small, relative to larger, disparity changes; observers are slower to react to smaller disparity changes and observers misperceive smaller disparity changes as being perceptually delayed. Interestingly, disparity magnitude influenced perceived timing more dramatically than it did stimulus change detection. Our data therefore suggest that perceived timing is both influenced by cortical processing and is shaped by sensory analyses subsequent to those that are minimally necessary for stimulus change perception.     

Dream Practices in Medieval Tibet

This essay presents a variety of medieval Tibetan Buddhist dream practices culled from many different sources, such as medical texts, biographies, religious texts, and folklore. Some of this material is here translated into English for the first time. The dreaming techniques presented in these texts bring out religious and philosophical connections between body and consciousness. The range and diversity of the original sources required a broad interdisciplinary approach using literary studies, religious studies, philosophy, linguistics, and other disciplines.     

A Historical Loop of One Hundred Years: Similarities Between 19th Century and Contemporary Dream Research

Contemporary cognitive and neuropsychological approaches to dreaming show striking methodological and conceptual similarities with the scientific dream literature of the last century. The use of introspective dream reports and the emphasis on dream phenomenology are characteristic of both periods but were bannished during the first half of this century, the former by behaviorism, the latter by psychoanalysis. Three main common axioms of 19th century and contemporary dream research are described: (a) dream experience results from cognitive syntheses realized in the absence of external constraints; (b) dream narrative or dream coherency involves mental associative mechanisms; (c) dream bizarreness emerges from a cerebral state characterized by functional dissociation. According to these three axioms, the observation of dream phenomena reveals that distinct cognitive processes might function in a partly autonomous, automatic, and dissociated way, making dreaming a unique model of these cognitive processes.     

Conscious experiences and high-density EEG patterns predicting subjective sleep depth

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On Folk Paroemias,National Consciousness,and “Little Russianness” as an Ethnopsychological Phenomenon

The author is interested in the relationship between the awareness of ethnic groups and other components of their psyche. Associative reactions of different ethnic groups serve as the material of the study. Analyzing proverbs is used to reveal specific ethnic imaginary structure of consciousness. A specific ethnic focus group is people living in region called “Malaya Russ’” in the Ukraine starting from the middle ages. Empirical material is collected from research projects before the 1930s.     

Self-awareness and the emergence of mind in primates

To date humans, chimpanzees, and orangutans are the only species which have been shown capable of recognizing themselves in mirrors. Several species of macaques have now been provided with years of continuous exposure to mirrors, but they still persist in reacting to their reflection as if they were seeing other monkeys. Even gibbons (apes) and gorillas (great apes) seem incapable of learning that their behavior is the source of the behavior depicted in the image. Most primates, therefore, appear to lack a cognitive category for processing mirrored information about themselves. The implications of these data for traditional views of consciousness are considered briefly, and a recent attempt to develop an operant analog to self-recognition is critically evaluated. Finally, an attempt is made to show that self-awareness, consciousness, and mind are not mutually exclusive cognitive categories and that the emergence of self-awareness may be equivalent to the emergence of mind. Several indices of “mind” which can be applied to nonhuman species are discussed in the context of an attempt to develop a comparative psychology of mind.     

Evolution of structure and information processing in the nervous system: Part IV of a general theory

Starting from fundamental principles, evolution of the nervous system is modelled as a random walk process in a multidimensional representation space (the F-space). This space is not flat, it is highly structured in terms of step probability. Fundamental considerations of evolutionary speed, efficiency of information processing, and priorities lead to specific theoretical predictions of the most probable pathways of evolution of the nervous system and its mechanisms of information processing. These processes are represented as vector paths (F-paths) in the F-space. Cognition becomes a process of correlations of the input signal to information stored in memories. Higher level brain processes involve extrapolation and interpolation along F-paths, input data reduction by clearly specifiable abstraction methods, and a unique process using abstracted analogs. These processes define and limit what the brain does and how it can do it. These considerations lead to certain inevitable conclusions (consequences of the fundamental principles) for the basis of our logical reasoning, decision-making, the process of dreaming (conscious and sleep), and explicit definitions of consciousness, unconsciousness, and personality. Detailed applications of this theory for analyzing empirical findings are suggested in the final paragraphs.     

Reply to Domhoff (2004): Dream Research in the Court of Public Opinion.

The author responds to Domhoff's critique (see record 2004-11640-001). He argues that the REM = dreaming equation was widely accepted at the time of his research. Misgivings about this equation by specialists in the dream research community were not shared by the wider public. The impression that the REM = dreaming equation disproves Freudian dream theory was actively propagated to this wider public between the 1970s and 1990s. The author's aim in the nonspecialist book criticized by Domhoff was to correct that specific misimpression, not to review the world literature. The author concludes with a brief statement of his views on Freudian dream theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Single-neuron theory of consciousness

By most accounts, the mind arises from the integrated activity of large populations of neurons distributed across multiple brain regions. A contrasting model is presented in the present paper that places the mind/brain interface not at the whole brain level but at the level of single neurons. Specifically, it is proposed that each neuron in the nervous system is independently conscious, with conscious content corresponding to the spatial pattern of a portion of that neuron's dendritic electrical activity. For most neurons, such as those in the hypothalamus or posterior sensory cortices, the conscious activity would be assumed to be simple and unable to directly affect the organism's macroscopic conscious behavior. For a subpopulation of layer 5 pyramidal neurons in the lateral prefrontal cortices, however, an arrangement is proposed to be present such that, at any given moment: (i) the spatial pattern of electrical activity in a portion of the dendritic tree of each neuron in the subpopulation individually manifests a complexity and diversity sufficient to account for the complexity and diversity of conscious experience; (ii) the dendritic trees of the neurons in the subpopulation all contain similar spatial electrical patterns; (iii) the spatial electrical pattern in the dendritic tree of each neuron interacts non-linearly with the remaining ambient dendritic electrical activity to determine the neuron's overall axonal response; (iv) the dendritic spatial pattern is reexpressed at the population level by the spatial pattern exhibited by a synchronously firing subgroup of the conscious neurons, thereby providing a mechanism by which conscious activity at the neuronal level can influence overall behavior. The resulting scheme is one in which conscious behavior appears to be the product of a single macroscopic mind, but is actually the integrated output of a chorus of minds, each associated with a different neuron.     

Some Nonhuman Animals Can Have Pains in a Morally Relevant Sense

In a series of works, Peter Carruthers has argued for the denial of the title proposition. Here, I defend that proposition by offering direct support drawn from relevant sciences and by undercutting Carruthers argument. In doing the latter, I distinguish an intrinsic theory of consciousness from Carruthers relational theory of consciousness. This relational theory has two readings, one of which makes essential appeal to evolutionary theory. I argue that neither reading offers a successful view.