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[The characteristics of visual information processing in persons of different ages].

Remarked the information of the computer operators (fifty persons aged from 18 to 67 years) was studied under conditions of the modelled computer operation. The results obtained show that the process of remarked the information of operators is characterized by a decrease in professional working capacity due to an overstrain of physiological reserves of an organism. Dynamics of their ageing involution includes four stages: professional training (age 18-21), maximal professional working capacity (age 26-28), professional ageing (age 29-40), and accelerated professional ageing (age after 40).

Adolescent↗

Pictorial cues and three-dimensional information processing in early infancy.

Adults derive 3-D information from 2-D images by initially processing local line junction cues and then combining information from many junctions. Prior research indicates that 3-month-olds are sensitive to 3-D cues in individual line junctions. In Experiment 1, we examined whether infants are sensitive to holistic combinations of line junctions that adults use to derive overall 3-D structure. Infants detected a misoriented shape in an array depicting 3-D blocks but not in 2-D patterns that contained all of the trilinear junctions of the 3-D shapes but without the connecting lines. Thus, like adults, infants exhibited sensitivity to holistic combinations of line junctions rather than to individual junctions. In Experiment 2, when confronted with two test patterns, one containing an individual novel element among 15 familiar elements and the other containing a single familiar element among 15 novel elements, infants preferred to look at the former pattern in the 3-D condition but at the latter pattern in the 2-D condition. Thus, akin to pop-out in adults, discrepancies in 3-D cues selectively engaged infants' attention. These results suggest that 3-month-olds are not only sensitive to holistic combinations of line junctions that adults use to derive 3-D information but also selectively attend to these 3-D cues in static images.

Analysis of Variance↗

Principles of auditory information-processing derived from neuroethology.

For auditory imaging, a bat emits orientation sounds (pulses) and listens to echoes. The parameters characterizing a pulse-echo pair each convey particular types of biosonar information. For example, a Doppler shift (a difference in frequency between an emitted pulse and its echo) carries velocity information. For a 61-kHz sound, a 1.0-kHz Doppler shift corresponds to 2.8 ms-1 velocity. The delay of the echo from the pulse conveys distance (range) information. A 1.0-ms echo delay corresponds to a target distance of 17 cm. The auditory system of the mustached bat, Pteronotus parnelli, from Central America solves the computational problems in analyzing these parameters by creating maps in the cerebral cortex. The pulse of the mustached bat is complex. It consists of four harmonics, each of which contains a long constant-frequency (CF) component and a short frequency-modulated (FM) component. Therefore, there are eight components in the emitted pulse (CF1-4 and FM1-4). The CF signal is particularly suited for target velocity measurement, whereas the FM signal is suited for target distance measurement. Since the eight components differ from each other in frequency, they are analyzed in parallel at different regions of the basilar membrane in the inner ear. Then, they are separately coded by primary auditory neurons and are sent up to the auditory cortex through several auditory nuclei. During the ascent of the signals through these auditory nuclei, neurons responding to the FM components process range information, while other neurons responding to the CF components process velocity information. A comparison of the data obtained from the mustached bat with those obtained from other species illustrates both the specialized neural mechanisms specific to the bat's auditory system, and the general neural mechanisms which are probably shared with many different types of animals.

Afferent Pathways↗

Information processing in negative feedback neural networks.

Information theory suggests that extraction of the principal sub-space from data is useful when the input to a neural network is corrupted with additive noise. A number of neural network algorithms exist which can find this principal sub-space, many of which also extract the principal components of the input. However, when there is noise on both input and output of a network, simply extracting the principal sub-space (or components) is not sufficient to optimize information capacity. An approximate solution to maximizing information capacity would be to extract the principal sub-space of components with variances above a certain threshold, and then ensure that these are uncorrelated and that they have equal variance at the output. A neural network is described which uses negative feedback connections to achieve this uncorrelated, equal-variance solution.

Journal Article↗

Information processing, dimensionality reduction and reinforcement learning in the basal ganglia.

Modeling of the basal ganglia has played a major role in our understanding of this elusive group of nuclei. Models of the basal ganglia have undergone evolutionary and revolutionary changes over the last 20 years, as new research in the fields of anatomy, physiology and biochemistry of these nuclei has yielded new information. Early models dealt with a single pathway through the nuclei and focused on the nature of the processing performed within it, convergence of information versus parallel processing of information. Later, the Albin-DeLong "box-and-arrow" model characterized the inter-nuclei interaction as multiple pathways while maintaining a simplistic scalar representation of the nuclei themselves. This model made a breakthrough by providing key insights into the behavior of these nuclei in hypo- and hyper-kinetic movement disorders. The next generation of models elaborated the intra-nuclei interactions and focused on the role of the basal ganglia in action selection and sequence generation which form the most current consensus regarding basal ganglia function in both normal and pathological conditions. However, new findings challenge these models and point to a different neural network approach to information processing in the basal ganglia. Here, we take an in-depth look at the reinforcement driven dimensionality reduction (RDDR) model which postulates that the basal ganglia compress cortical information according to a reinforcement signal using optimal extraction methods. The model provides new insights and experimental predictions on the computational capacity of the basal ganglia and their role in health and disease.

Animals↗

Comparison of information processing technologies.

OBJECTIVE: To examine the type of information obtainable from scientific papers, using three different methods for the extraction, organization, and preparation of literature reviews. DESIGN: A set of three review papers was identified, and the ideas represented by the authors of those papers were extracted. The 161 articles referenced in those three reviews were then analyzed using 1) a formalized data extraction approach, which uses a protocol-driven manual process to extract the variables, values, and statistical significance of the stated relationships; and 2) a computerized approach known as "Idea Analysis," which uses the abstracts of the original articles and processes them through a computer software program that reads the abstracts and organizes the ideas presented by the authors. The results were then compared. The literature focused on the human papillomavirus and its relationship to cervical cancer. RESULTS: Idea Analysis was able to identify 68.9 percent of the ideas considered by the authors of the three review papers to be of importance in describing the association between human papillomavirus and cervical cancer. The formalized data extraction identified 27 percent of the authors' ideas. The combination of the two approaches identified 74.3 percent of the ideas considered important in the relationship between human papillomavirus and cervical cancer, as reported by the authors of the three review articles. CONCLUSION: This research demonstrated that both a technically derived and a computer derived collection, categorization, and summarization of original articles and abstracts could provide a reliable, valid, and reproducible source of ideas duplicating, to a major degree, the ideas presented by subject specialists in review articles. As such, these tools may be useful to experts preparing literature reviews by eliminating many of the clerical-mechanical features associated with present-day scientific text processing.

Bibliometrics↗

Information-processing abnormalities: trait- and state-dependent components.

Schizophrenics were compared to schizoaffective, bipolar, and nonpsychotic depressed patients in a visual masking paradigm in which an informational target stimulus was followed at varying intervals by a noninformational masking stimulus. In limiting the availability of the sensory signal provided by the target stimulus, the mask was used to probe how information from the environment enters and is processed by the central nervous system. The use of the masking paradigm was originally based on the hypothesis that thought disorder is a result of a more primary dysfunction in the processes that precede and result in thought. Results confirmed previous findings of a performance deficit in the schizophrenics when compared to nonpsychotic controls. Schizoaffective and bipolar patients also showed evidence of impaired processing, however. Results were interpreted in terms of a trait/state formulation in which impaired information processing is seen as a fundamental trait of schizophrenia spectrum disorders and as a state that can covary with psychotic illness in general. A unifying concept centers on the effects of psychopathological conditions on an individual's processing resources that results in either underprovision or overprovision of information from sensory input to complex cognitive operations dependent on the cerebral cortex. Findings from a variety of paradigms are consistent with those of the masking paradigm in revealing that the processing deficits of schizophrenics are time dependent and occur in the 500 ms following stimulus input.

Adult↗

Metabolic drug pointing and information processing.

Computer supported drug design is based on the biochemical information for the prediction of alternative bio-chemical pathways. Molecular information on genes, proteins, biochemical reactions, mutations, inborn errors and metabolic diseases are available via internet. Based on this information we developed an information retrieval and processing concept combining knowledge about metabolic diseases and biochemical effects.

Artificial Intelligence↗

Discrete versus continuous stage models of human information processing: in search of partial output.

This article introduces a new technique designed to study the flow of information through processing stages in choice reaction time tasks. The technique was designed to determine whether response preparation can begin before stimulus identification is complete ("continuous" models), or if a stimulus must be fully identified prior to any response activation ("discrete" models). To control the information available at various times during stimulus identification, some relevant stimulus characteristics were made easy to discriminate and some were made hard to discriminate. The experimental strategy was to look for effects of partial output based on information conveyed by characteristics that were easy to discriminate. The technique capitalized on the fact, demonstrated in Experiment 1, that preparation of two response fingers on the same hand is more effective than preparation of two response fingers on different hands. The usefulness of partial output was varied by manipulating the assignments of stimuli to responses. For some mappings partial information could contribute to effective response preparation because the responses consistent with partial information were assigned to fingers on the same hand. For other mappings partial information could not contribute to effective response preparation because the responses consistent with partial information were assigned to fingers of different hands. Performance differences between these mappings were considered evidence that partial information about a stimulus was transmitted to response activation processes before the stimulus was uniquely identified, and thus were considered evidence against discrete transmission of information about the stimulus as a whole. A variety of stimulus sets were studied; the results suggest that information is transmitted discretely with respect to stimulus codes, although distinct codes activated by a single stimulus may be transmitted at different times.

Adult↗

Target entitativity: implications for information processing about individual and group targets.

It is hypothesized that perceptions of entitativity (i.e., seeing social targets as possessing unity and coherence) have important implications for how one organizes information about, and forms impressions of, individual and group targets. When perceivers expect entitativity, they should form an integrated impression of the target, resulting in on-line judgments. However, when perceivers expect little entitativity, they should not process target-relevant information in an integrative fashion, resulting in memory-based judgments. Although many factors affect perceptions of entitativity, the current study focused on expectations of similarity and behavioral consistency. It was predicted that in general, perceivers expect greater entitativity for individual than group targets. However, when explicitly provided with similar expectancies of entitativity, information processing would be similar for both individual and group targets. Two experiments supported these predictions, using recall, memory-judgment correlation, and illusory correlation measures.

Adult↗

Ascending visceral regulation of cortical affective information processing.

Over a century ago, William James proposed that strong emotions represent the perceptual consequences of somato-visceral feedback. Although the strong form of this conception is no longer viable, considerable evidence has accumulated indicating a range of visceral influences on higher neurobehavioural processes. This literature has only recently begun to consolidate, because earlier reports generally remained at the demonstration level, and pathways and mechanisms for such influences were uncertain. Recently, specific effects of visceral feedback have become apparent on cortical activity, cerebral auditory-evoked responses, anxiety, memory and behavioural aspects of immunological sickness. Moreover, considerable progress has been made recently in determining the specific neural pathways and systems underlying these actions, especially the role of noradrenergic projections from the nucleus of the tractus solitarius and the locus coeruleus to the amygdala in memory processes, and to the basal forebrain in the processing of anxiety-related information. The present paper highlights selected recent findings in this area, and outlines relevant structures and pathways involved in the ascending visceral influence on higher neurobehavioural processes.

Affect↗

Neuropsychological correlates of information-processing by children with Down syndrome.

Nine children with Down syndrome were compared to two groups of nonretarded children, one similar in CA, the other a chronologically younger group of similar MA. The event-related brain potential (ERP) and reaction time (RT) results indicated that children with Down syndrome process some types of auditory information more slowly than do MA- or CA-matched nonretarded children. They were found to differ from nonretarded children in the scalp distribution of amplitudes of certain ERP components. Finally, the speed of processing and amplitude differences that were found could not be explained on the basis that children with Down syndrome are simply maturationally delayed in their cognitive abilities. The possible relation of these neuropsychological (ERPs) and performance (RT) differences to pathological changes in the hippocampus were discussed.

Age Factors↗