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Problems of the analysis of altered states of consciousness.

It is assumed on the basis of data that have been obtained that altered states of consciousness (ASC) arise during the performance of operator activity under conditions of monotony, when modulating influences in the minute range of fluctuations are experienced in the process. This modulation promotes the attenuation or intensification of the degree of ASC; this is reflected in corresponding shifts in attention and in the quality of operator actions relating to recognition of visual images. These results point to the important role of the modulating system of the brain, and of its infraslow wave manifestations in the activity of consciousness whose content is determined by informational processes.

Adult↗

You can play 20 questions with nature and win: categorical versus coordinate spatial relations as a case study.

Alan Newell famously asserted that "You can't play 20 questions with nature and win" (Newell, A. (1973). You can't play 20 questions with nature and win. In W.G. Chase (Ed.), Visual information processing. New York: Academic Press.), and specifically focused on the futility of studying binary distinctions. However, the distinction between categorical and coordinate spatial relations representations has turned out to be fruitful. In this brief article, the categorical/coordinate distinction is treated as a case study, as a way to address a more general point, namely how to play 20 questions with nature and win. The key to studying binary distinctions may lie in the ways this one differs from previous ones. First, from the outset this distinction was cast within the context of a theory of a more general processing system; second, it was formulated from the perspective of multiple levels of analysis within a processing system, and thereby bridges characteristics of information processing with characteristics of the brain.

Brain↗

Different outcomes after acute and chronic treatment with nicotine in pre-pulse inhibition in Lister hooded rats.

Excessive tobacco consumption by schizophrenic patients may be a form of self-medication, and nicotine in tobacco may alleviate deficits in information processing. We tested this hypothesis by determining whether nicotine (acute/chronic) would improve information processing in the rat using pre-pulse inhibition as a model. In study 1, rats were injected with nicotine 10 min prior to placement in startle chambers (0.001-0.1 or 0.03-0.3 mg/kg, s.c.). In study 2, rats were injected with either saline or nicotine (0.4 mg/kg, s.c.) for 21 consecutive days and assessed for locomotor activity, pre-pulse inhibition and changes in [3H]nicotine binding in whole brain. Acutely, nicotine had no effect on pre-pulse inhibition. By contrast, after chronic nicotine treatment, rats demonstrated a robust deficit in pre-pulse inhibition and significant increases in locomotor activity and [3H]nicotine binding. The deficit in pre-pulse inhibition after chronic treatment with nicotine may be the result of non-specific behavioural activation due to increased mesolimbic dopamine release or, possibly, nicotine may rapidly desensitize nicotinic receptors important for normal information processing.

Animals↗

Does a warning signal accelerate the processing of sensory information? Evidence from recognition potential responses to high and low frequency words.

Electrophysiological and behavioral data were obtained in 12 subjects who detected valid words in a background stream of random letter strings. Behavioral reaction time (RT) showed significant effects of warning signal presentation and the frequency of word usage in printed literature. Cross-correlation functions were used to estimate delays of electrophysiological responses. The critical response was the recognition potential (RP). The RP is a response of the brain that occurs when a person views recognizable images, such as words, pictures, or faces. Its latency is usually less than 300 ms. Both the RP and longer latency activity occurring at approximately 400--600 ms were delayed more for low than for high frequency words. The longer latency responses showed shorter delay if a warning signal was presented, but the RP did not. The results supported the idea that a non-informative warning signal decreases RT by altering response-related processes without facilitating sensory processes.

Adult↗

Functional and anatomical decomposition of face processing: evidence from prosopagnosia and PET study of normal subjects.

Studies of brain-damaged patients have revealed the existence of a selective impairment of face processing, prosopagnosia, resulting from lesions at different loci in the occipital and temporal lobes. The lesions are often extensive, and it is unclear what functional aspects of face processing are normally served by the damaged areas, and whether they are uniquely devoted to the processing of faces. These issues are further addressed through a combined magnetic resonance imaging (MRI) and positron emission tomography (PET) study of regional cerebral blood flow (rCBF) in normal subjects performing different tasks of face and object processing. The results indicate different patterns of cerebral activation depending on the requirements of the tasks within the processing of faces, as well as a clear dissociation of the neural substrates underlying face and object processing. These results are compared with radiological data from prosopagnosic patients, and are put in relation with the patterns of deficits observed in the patients as a function of the location of their lesions. Together, the findings offer new evidence regarding the functional neuroanatomy of face and object processing.

Agnosia↗

[Origin and evolution of life and intellect from the point of view of information processing].

Beginning of life and intellect on the Earth is determined by the fact that synthesis of semantic information about algorithms of chemical transformation for appointed classes of chemical compounds is not accompanied by the information synthesis, but is controlled by chance in genetic material. Genetic information as memorizing accidental choice always arises as a result of the environment interaction, when memorizing realization in the form of repeated reproduction occurs on the basis of processes radically different from those which created initial genetic chance. Such stepped synthesis of information has hierarchical character and it is described by entropy of different dimensions. Entropy is determined by conditional probabilities. Therefore as a form of life becomes complicated, the entropy is decreased within the limits of the given hierarchical step. The part of entropy depending on the number of elements of the system (cells, individuals, etc.) always increases in the memorizing process, i. e. life defines the maximum of entropy production (but not the minimum like in nature). This fact settles paradoxes of chance in Darwinism: as a result of entropy decrease within higher hierarchical step the simbiotic processes for more complex forms of life can arise with great probability. For instance, rapidity of evolution of human brain given by supplementary chance in the mechanism of fecundation under the conditions of biochemical pressure of androgenes both, on the brain development and on muscular force at the same time. Synthesis of information in the brain is determined by the same principles, but extremums of the thermo-dynamic potential (their analogues in logic) are based on an arbitrary system of axioms. As a whole life and intellect are not fluctuations pointed against entropy increases, but they arose according to spontaneous process of entropy development.

Biological Evolution↗

[Changes in the rate and accuracy of information processing in the computer training of upper-grade pupils].

The basic activity of the student during the "computer training process" is the introduction and processing of information. In the dialogue regime of work, between student and computer, the velocity and accuracy of the information processing take important place. In this aspect, special attention is given to the changes in the indicated indices during the computer lesson, computer plays and the traditional training. Studies are carried out on 30 students from classes X and XI, educated in vocational school "V. Levski", the town of Pravets. For the purpose is used electron determinator with test programme, containing consecutively exposure to 50 visual stimulators in red, blue, green, yellow and white colours at 1,2 s/speed. The results as a whole show that the most favourable results concerning the computer plays, very likely could be explained with the diversion effect and the positive motivation adjustment to the activity performed. By means of dispersion analysis is established, that only the type of activity has an essential effect on the velocity and accuracy of the information processing.

Bulgaria↗

Some thoughts on the nature of mind. A holistic concept of nervous system function.

Some practical neurological ideas concerning the nature of mind are presented to assist clinicians in appreciating the fact that brain physiology first creates and then serves the mind--the highest of the hierarchical functions of the nervous system. The qualities of the mind are shaped and modulated by life experience and many disturbed responses can be tempered by a knowledgeable approach. To gain a holistic concept of the functioning nervous system one must recognize and accept that all manifestations of behavior, including those termed psychological, are the product of physiological processes.

Animals↗

[Rorschach response process in schizophrenia].

Although H. Rorschach considered the Rorschach test as a perceptual experiment, little research has been done on the experiment. Moreover, the Rorschach signs of perceptual impairment in schizophrenia, which he indicated and many scholars have supported, have never been examined by the perceptual experiments. The purpose of this study is to make clear the relationship between the Rorschach response and the perceptual process in schizophrenia by investigating cognitive activities using eye-mark recorder. Four Rorschach cards were selected, achromatic cards I and V, and chromatic cards II and VIII. Thirty chronic schizophrenic inpatients (who met DSM-III-R for "Residual Type", and whose negative symptoms were evaluated according to SANS) and 20 normals were all administered the Rorschach test in the used manner but they wore an eye-mark recorder. Their eye movements during reporting the initial response to each card were recorded on the VTR connected with the eye-mark recorder. On the response of each card, five eye movement items (1.total response time; 2.number of eye-fixation movements/sec.; 3.mean eye-fixation time; 4.mean eye-fixation tracking length, and 5.eye-fixation frequency on each detail area) were measured and analyzed. By their initial response, subjects were divided into 3 response groups: Popular response group, non-Popular response group and Rejection group. On the achromatic cards I and V, cognitive activities during delivering Popular response in schizophrenia were examined in comparing with those of normals. On the chromatic cards II and VIII, after the eye movements of Popular response group in schizophrenia were compared with those of Normals, scanning activities of the non-Popular group, the Rejection group and the Popular group were investigated in comparing with each other among schizophrenics. On the achromatic cards with the most solid blots; Cards I and V, the schizophrenics could easily give a Popular response the same as normals. However, the visual scanning activity of schizophrenics was limited on a small detail area and inactive compared with normals. The results show the discrepancy between the response and the cognitive activity. On the achromatic cards, this suggests that the Rorschach response process in schizophrenia is different from those of normal's, even if the responses of schizophrenia is the same as those of normals. On the chromatic cards with the most broken blots; Cards II and VIII, most of schizophrenics failed to give any response, hardly gave a Popular response but a non Popular response. Among schizophrenics, the few Popular groups indicated a limited pattern with poor scanning on the blot. Besides in SANS, their negative symptoms showed high attentional impairment. Although the non-Popular group gave many color responses, they avoided looking at the color areas, As for the Rejection group, although eye-fixation shifted and searched all over the blots, the subjects failed to give any response. Particularly on Card II, some of their visual focal points scattered on the white space areas out of the blot. This implies the failure of perception focusing on the appropriate blots as the relative stimulus. This implies the impairment of selective attention in schizophrenia. These results suggest that it didn't reveal in the usual manner of Rorschach test until the observation with eye-mark recorder made it possible to show us the response process in schizophrenia.

Adult↗