Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Information Processing”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31Linked to original sources

Information-processing demands in electrosensory and mechanosensory lateral line systems.

The electrosensory and mechanosensory lateral line systems of fish exhibit many common features in their structural and functional organization, both at the sensory periphery as well as in central processing pathways. These two sensory systems also appear to play similar roles in many behavioral tasks such as prey capture, orientation with respect to external environmental cues, navigation in low-light conditions, and mediation of interactions with nearby animals. In this paper, we briefly review key morphological, physiological, and behavioral aspects of these two closely related sensory systems. We present arguments that the information processing demands associated with spatial processing are likely to be quite similar, due largely to the spatial organization of both systems and the predominantly dipolar nature of many electrosensory and mechanosensory stimulus fields. Demands associated with temporal processing may be quite different, however, due primarily to differences in the physical bases of electrosensory and mechanosensory stimuli (e.g. speed of transmission). With a better sense of the information processing requirements, we turn our attention to an analysis of the functional organization of the associated first-order sensory nuclei in the hindbrain, including the medial octavolateral nucleus (MON), dorsal octavolateral nucleus (DON), and electrosensory lateral line lobe (ELL). One common feature of these systems is a set of neural mechanisms for improving signal-to-noise ratios, including mechanisms for adaptive suppression of reafferent signals. This comparative analysis provides new insights into how the nervous system extracts biologically significant information from dipolar stimulus fields in order to solve a variety of behaviorally relevant problems faced by aquatic animals.

Action Potentials↗

Bandpass channels, zero-crossings, and early visual information processing.

Under appropriate conditions zero-crossings of a bandpass signal are very rich in information. The authors examine here the relevance of this result to the early stages of visual information processing, where zero-crossings in the output of independent spatial-frequency-tuned channels may contain sufficient information for much of the subsequent processing.

Humans↗

[Effect of psychotropic drugs on information processing].

Although psychopharmacology relies heavily upon precise, objective measurement of drug effects, the latter remain phenomenological unless they are relatable to clinically relevant disorders. Consequently, ideal drug testing procedures should not only be based upon understandable physiological principles, but also afford accurate, unequivocal measurement of parameters in models which are available in both animals and humans. In recent years the study of information processing via the peripheral visual system has emerged as a promising model having at least some of the aforementioned features. Much is known about the physiological characteristics of animal visual pathways. It is a unique property of the visual system, that the neurophysiological measures in animals find their analogue in the psychophysical measurements which can be carried out with great precision in humans. This relationship may be used to compare effects of drugs in neurophysiological studies of animals with their influence on perceptive phenomena in humans. However, whereas the animal peripheral visual system has been used to assess drug effects on information processing, there is a paucity of such studies in humans.

Animals↗

Information processing in very-low-birth-weight children with and without attention deficit disorder.

Very-low-birth-weight children (16 with and 45 without attention deficit/hyperactivity disorder) were matched to term-born controls (27 with attention deficit/hyperactivity disorder and 30 without) according to age, intelligence, and social class of their parents. The children were screened for motor, visual, and mental disabilities. The general aim of the study was to evaluate information processing stages using the additive factor method of Sternberg. The tasks consisted of computerized visual-motor letter recognition and arrow detection tasks. The tasks elicited similar prolongations of response times, increases in standard deviation of the response times, and increased error rates in the four groups. We conclude that very-low-birth-weight and control children do not differ in their information processing stages.

Age Factors↗

Verbal information-processing capabilities and cochlear implants: implications for preoperative predictors of speech understanding.

In this study, we examined preoperative verbal cognitive capacity in 11 deafened adults who were cochlear implant candidates and reexamined level of speech understanding after 6-8 months' experience with the implant. Verbal cognitive performance in the implant group was compared in a group of normal hearing subjects and in nonimplanted group of deafened adults. The three groups performed on par with each other with an exception: The individuals in the cochlear implant group and the nonimplanted group of deafened adults performed significatly worse than those of normal hearing in tasks in which use of internal speech is a key feature (i.e., rhyme judgement and lexical decision tasks). Postoperative observations of the implanted individuals' level of speech understanding suggest that it is possible to predict the level of speech understanding by means of a properative cognitive assessment. The characteristics of three verbal cognitive abilities prove to be critical indicators of 6 - 8 months' postoperative outcome: internal speech functioning, speed of verval information processing, and working memory capacity - the first factor proved the most decisive. We discuss the results with respect to direct versus indirect predictors of outcomes from cochlear implant operations and the effect of auditory deprivation on deafened adults' capability to process auditory information.

Journal Article↗

Memory performance, but not information processing speed, may be reduced during early pregnancy.

Several studies have investigated aspects of cognitive functioning during late pregnancy or in the period around delivery. The present paper describes a controlled study of neurocognitive functioning in an early phase of pregnancy (14 weeks). Seventy-one pregnant women and 57 control subjects matched for age and education were tested with a cognitive test battery. Intentional learning was tested with the Verbal Learning Test, retrieval from semantic memory with the Fluency Test, and speed of information processing with the Concept Shifting Test, the Stroop test, and the Letter Digit Substitution Test. Results show that performance on tests measuring intentional learning and retrieval from semantic memory were lower in the pregnant group during early pregnancy as compared to a closely matched nonpregnant group. In contrast, speed of information processing was not different between the two groups. The differences observed in memory performance were not large and further research is needed to establish their clinical significance. In addition, the results should be interpreted with care, because our study has a cross-sectional design, which has limitations concerning the fact that preexisting performance differences might be possible. Therefore, longitudinal studies are essential to ascertain clear associations between pregnancy and cognitive performance.

Adult↗

The dimensional complexity of the EEG during cognitive tasks reflects the impaired information processing in schizophrenic patients.

The aim of the present study was to investigate whether schizophrenic patients show a different change of the dimensional complexity of the EEG, as represented by the Grassberger-Procaccia correlation dimension D(2,) under cognitive challenge compared to normal control subjects. With respect to results reported in the literature, it was expected that the complexity of the signal under cognitive challenge is higher in schizophrenic patients than in normal control subjects reflecting the impaired information processing abilities of the patients. Eighty-seven schizophrenic and 30 matched control subjects performed two different types of the continuous performance task. The results revealed differences between schizophrenic patients and control subjects for the performance as well as the complexity measures. Schizophrenic patients produced more omission errors than normal subjects did. For the EEG complexity measure no differences occurred under the baseline condition. In contrast, during the first minute under task conditions the control subjects showed a decrease of the dimension while no changes were found for the schizophrenic group. These results occurred for both types of the cognitive task but they reached clear significance only in one of them. The results are interpreted as reflecting the ability of normal subjects to adapt their information processing system to the cognitive challenge and to focus their attention on the task while schizophrenic subjects do not show this adaptation to the task.

Adult↗

Information processing and attentional dysfunctions as vulnerability indicators in schizophrenia spectrum disorders.

The schizotypal personality disorder is believed to be part of the schizophrenic spectrum of disorders including schizophrenic patients as well as some of their seemingly unaffected relatives with discreet symptoms. Spectrum-individuals are characterised by a genetic vulnerability for schizophrenia. The vulnerability is connected with neurocognitive deficits independent of clinical state. Some cognitive dysfunctions are unspecific and probably related to non-genetic brain damage. A consistent finding has, however, been poor performance in tasks involving information processing and attention. The findings point to the existence of specific sensory-perceptual deficits or a general attentional dysfunction. Identification of cognitive disturbances characteristic not only of schizophrenics, but also of schizotypal disordered and their relatives in the boundaries of schizophrenia, is relevant in order better to understand the pathogenetic mechanisms and treatment of schizophrenia. In the present review clinical data are analysed based on models of vulnerability and information processing with reference to a characterisation of the neuro-integrative deficits that form the core abnormalities of the spectrum.

Attention↗

A study of parallel implicit and explicit information processing in patients with obsessive-compulsive disorder.

OBJECTIVE: This study examined implicit sequence learning in patients with obsessive-compulsive disorder (OCD) under dual-task conditions. Frontal-striatal networks support implicit learning and are implicated in the pathophysiology of OCD. Neuroimaging data suggest that during implicit learning, OCD patients use neural systems normally active during explicit learning to compensate for striatal dysfunction. METHOD: The authors examined implicit sequence learning in 25 OCD patients and 25 healthy comparison subjects using a dual-task paradigm, with subjects simultaneously engaged in an explicit memory task and an implicit learning task. They predicted that implicit learning in OCD subjects would be disrupted because concurrent explicit information-processing demands would prevent use of compensatory processes. RESULTS: OCD patients failed to show evidence of implicit learning and exhibited a significant deficit in comparison with healthy subjects. CONCLUSIONS: These results are consistent with the hypothesis that concurrent explicit and implicit information-processing demands interfere with implicit learning in OCD patients.

Attention↗

Using historical data for bioprocess optimization: modeling wine characteristics using artificial neural networks and archived process information.

Optimization of fermentation processes is a difficult task that relies on an understanding of the complex effects of processing inputs on productivity and quality outputs. Because of the complexity of these biological systems, traditional optimization methods utilizing mathematical models and statistically designed experiments are less effective, especially on a production scale. At the same time, information is being collected on a regular basis during the course of normal manufacturing and process development that is rarely fully utilized. We are developing an optimization method in which historical process data is used to train an artificial neural network for correlation of processing inputs and outputs. Subsequently, an optimization routine is used in conjunction with the trained neural network to find optimal processing conditions given the desired product characteristics and any constraints on inputs. Wine processing is being used as a case study for this work. Using data from wine produced in our pilot winery over the past 3 years, we have demonstrated that trained neural networks can be used successfully to predict the yeast-fermentation kinetics, as well as chemical and sensory properties of the finished wine, based solely on the properties of the grapes and the intended processing. To accomplish this, a hybrid neural network training method, Stop Training with Validation (STV), has been developed to find the most desirable neural network architecture and training level. As industrial historical data will not be evenly spaced over the entire possible search space, we have also investigated the ability of the trained neural networks to interpolate and extrapolate with data not used during training. Because a company will utilize its own existing process data for this method, the result of this work will be a general fermentation optimization method that can be applied to fermentation processes to improve quality and productivity.

Carbohydrate Metabolism↗

Olfactory information processing and temporal lobe epilepsy.

It has been suggested that olfactory information processing is impaired in patients with temporal lobe epilepsy. However, the existing evidence is not wholly in accordance with this notion. Patients with epileptogenic foci in the left temporal lobe, the right temporal lobe, or other brain regions were compared with normal control subjects in the identification and retention of common odors. All three patient groups were substantially and equally impaired in verbally labelling the odors in question. The patients with epilepsy associated with the left temporal lobe or with nontemporal regions showed no sign of any impairment on a test of immediate recognition memory for common odors. However, the patients with epilepsy associated with the right temporal lobe showed a specific disturbance in their retention of nameable odors. It is suggested that the latter patients were selectively impaired in their retrieval of the episodic memories which provide the context for the encoding of distinctive odors.

Adult↗

A 12-year prospective study of patterns of social information processing problems and externalizing behaviors.

This study investigated how discrete social information processing (SIP) steps may combine with one another to create distinct groups of youth who are characterized by particular patterns of SIP. SIP assessments were conducted on a community sample of 576 children in kindergarten, with follow-up assessments in grades 3, 8, and 11. At each age, four profiles were created, representing youth with no SIP problems, with early step SIP problems (encoding or making hostile attributions), with later step SIP problems (selecting instrumental goals, generating aggressive responses, or evaluating aggression positively), and with pervasive SIP problems. Although patterns of SIP problems were related to concurrent externalizing during elementary school, the consistency between cognition and future externalizing behavior was not as strong in elementary school as it was between grades 8 and 11. In some cases, youth characterized by the co-occurrence of problems in early and later SIP steps had higher externalizing scores than did youth characterized by problems in just one or the other.

Adolescent↗

Social information processing in mild mentally retarded children.

This study examined the social information processing (SIP) skills of mild mentally retarded (MR) children using Dodge's model. Six sets of pictures depicting provocation situations were used to elicit measures of accuracy of interpretation to accidental and hostile cues, attribution of ambiguous cues, and hostile and nonhostile behavior responses to all three types of cues. MR children were compared to nonretarded groups matched for chronological age (CA-matched) and mental age (MA-matched) on these variables. Compared to both nonretarded groups, the MR group was less accurate in interpretation of accidental cues and more hostile in their responses to the ambiguous cues. The latter finding remained even after partialing out externalizing behavior problems. The results are discussed in terms of factors associated with SIP skills, and the assessment and treatment of MR children.

Aggression↗

Obsessional states: anxiety disorders or schizotypes? An information processing and personality assessment.

This paper presents evidence that on an information processing task, designed to investigate putative inhibitory mechanisms in selective attention, obsessive-compulsive disordered individuals can be clearly distinguished from other anxiety disorder clients and show significantly higher scores on questionnaire measures designed to detect schizotypy in the normal population. It is suggested that these results provide some support for the idea that obsessive-compulsive disorder may be misclassified as an anxiety disorder and may in fact be categorically more closely aligned to the schizophrenic constellation of disorders.

Adult↗

Genetic covariance among measures of information processing speed, working memory, and IQ.

The genetic relationship between lower (information processing speed), intermediate (working memory), and higher levels (complex cognitive processes as indexed by IQ) of mental ability was studied in a classical twin design comprising 166 monozygotic and 190 dizygotic twin pairs. Processing speed was measured by a choice reaction time (RT) task (2-, 4-, and 8-choice), working memory by a visual-spatial delayed response task, and IQ by the Multidimensional Aptitude Battery. Multivariate analysis, adjusted for test-retest reliability, showed the presence of a genetic factor influencing all variables and a genetic factor influencing 4- and 8-choice RTs, working memory, and IQ. There were also genetic factors specific to 8-choice RT, working memory, and IQ. The results confirmed a strong relationship between choice RT and IQ (phenotypic correlations: -0.31 to -0.53 in females, -0.32 to -0.56 in males; genotypic correlations: -0.45 to -0.70) and a weaker but significant association between working memory and IQ (phenotypic: 0.26 in females, 0.13 in males; genotypic: 0.34). A significant part of the genetic variance (43%) in IQ was not related to either choice RT or delayed response performance, and may represent higher order cognitive processes.

Adolescent↗

Domestically violent and nonviolent male inmates' responses to their partners' requests for condom use: testing a social-information processing model.

This study used a model derived from social-information processing theory to investigate how men with a history of domestic violence would react to a condom request. The study used path analysis to examine men's attributional and evaluative responses as potential predictors of coercion and condom use compliance. Men responded to a hypothetical situation in which their main partner requested that they use a condom. Among 100 county jail inmates, men who used severe forms of domestic violence differed from moderately violent and nonviolent men in their tendency to react negatively to condom requests. Condom-specific attributions were significant predictors of condom use and coercive actions but were not consistently different across abuse groups. Attributions that increased the likelihood of negative responding were infidelity, selfishness, competition for dominance, or suspicion of the man's fidelity.

Adult↗

[The role of cortical oscillatory activity in information processing mechanisms].

INTRODUCTION: Cortical oscillatory activity has been related recently to information processing mechanisms. Synchronization between different neuronal groups can explain how he different features of an object can be integrated into a single perception (binding), or how different muscular groups can be co-ordinated into a single movement. DEVELOPMENT: This paper reviews the knowledge up to date on the role of cortical oscillatory activity in perceptive binding and motor control. Also, the participation of alterations in cortical oscillatory activity in different neurological diseases (epilepsy, Parkinson's disease) is proposed, basing on available data. CONCLUSION: The study of the changes in cortical oscillatory activity (specially in the so-called gamma band 30-60 Hz) can contribute to current knowledge on the physiology and pathophysiology of the different cortical areas involved in perceptive and motor tasks.

Cerebral Cortex↗

The effects of early maternal deprivation on auditory information processing in adult Wistar rats.

BACKGROUND: There is now ample evidence that schizophrenia is due to an interaction between genetic and (early) environmental factors which disturbs normal development of the central nervous system and ultimately leads to the development of clinical symptoms. Recently, we showed that a single 24-hour period of maternal deprivation of rat pups at postnatal day 9 leads to a disturbance in prepulse inhibition, similar to what is seen in schizophrenia. The present set of experiments was designed to further characterize the information processing deficits of maternally deprived Wistar rats. METHODS: Wistar rats were deprived from their mother for 24 hours on postnatal day 9. At adult age, rats were tested in the acoustic startle paradigm for prepulse inhibition and startle habituation. Rats were also tested in the evoked potentials paradigm for auditory sensory gating. RESULTS: The results show that maternal deprivation led to a reduction in acoustic startle habituation and auditory sensory gating in adult rats. Moreover, maternal deprivation disrupted prepulse inhibition but only when the prepulses were given shortly (50-100 milliseconds) before the startle stimulus. At longer intervals (250-1000 milliseconds), no effect was seen. CONCLUSIONS: The implications for the model and the development of disturbances in information processes are discussed.

Acoustic Stimulation↗