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PubMed1986

Effect of coffee on the speed of subject-paced information processing.

A continuously subject-paced and monetarily reinforced information-processing task was used to test whether caffeine might stimulate performance beyond the ceiling imposed by fatigue. A 3 X 2 design was adopted with the three doses 0, 150, and 450 mg caffeine and with decaffeinated coffee and fruit juice as vehicles. Two groups of 10 subjects selected to represent extremes on the extraversion-introversion scale participated in the experiment. The results revealed no differences between the two groups nor between the two drug vehicles, but caffeine at both dose levels improved performance significantly. Fatigue-induced performance decrements across the sessions reached significance, but no interaction was obtained between fatigue and drug action, supporting the view that caffeine can improve performance beyond a mere restoration of fatigue.

Caffeine↗
PubMed1998

Cognitive speed in nondemented Parkinson's disease.

Studies of speed of cognitive processing in Parkinson's disease (PD) have yielded mixed results. This may relate in part to a differential effect on cognitive speed by the type of information to be processed. In the present study, we compared medication fasted, nondemented individuals with mild idiopathic PD (N = 26) with age-matched controls (N = 12) on a test requiring easy and hard same-different discriminations for verbal, quantitative, and spatial information, as well as on a traditional memory scanning paradigm. A voice-activated relay rather than a key press was used to eliminate the need for limb and finger movements. Simple reaction time and movement time were also measured in a task requiring subjects to move a hand held stylus to a designated target. The PD group performed as fast as the control group across all tasks except movement time. Thus, in our paradigm, the presence of PD alone does not predict cognitive slowing in the presence of motor slowing.

Aged↗
PubMed1991

Automatic processing: effects of temperature and time changes on sensitometric properties of ULTRA-SPEED and EKTASPEED films.

The effects of changes in the processing temperature and time of automatic processors were studied with Kodak ULTRA-SPEED and EKTASPEED dental x-ray films. Speeds and inherent contrasts were derived for the two films from sensitometric curves at seven different temperatures and at five different processing times. As opposed to manual processing, only a slight change in film fog was observed with increases in automatic processing temperature or time. Film speed and contrast could be increased by increasing the processing temperature or time. The EKTASPEED film was more sensitive to these changes than was the ULTRA-SPEED film. Temperature had a stronger influence than processing time. All films were of archival storage quality except those processed at the low processing times of 2.5 or 3.5 minutes, and at the low processing temperature of 21 degrees C.

Evaluation Studies as Topic↗
PubMedDate not supplied

Structure Elucidator: a versatile expert system for molecular structure elucidation from 1D and 2D NMR data and molecular fragments.

StrucEluc is an expert system that allows the computer-assisted elucidation of chemical structures based on the inputs of a series of spectral data including 1D and 2D NMR and mass spectra. The system has been enabled to allow a chemist to utilize fragments stored in a fragment database as well as user-defined fragments submitted by the chemist in the structure elucidation process. The association of fragments in this way has been shown to dramatically speed up the process of structure generation from 2D NMR data and has helped to minimize or eliminate the need for user intervention thereby further enabling the vision of automated elucidation. The use of fragments has frequently transformed very difficult 2D NMR elucidation challenges into easily solvable tasks. A strategy to utilize molecular fragments has been developed and optimized based on specific challenging examples. This strategy will be described here using real world examples. Experience gained by solving more than 150 structure elucidation problems from a variety of literature sources is also reviewed in this work.

Journal Article↗
PubMed1979

Cognitive speed and subsequent intellectual development: a longitudinal investigation.

The hypothesis that a measure of intellectual speed assessed at one point in time would predict intellectual achievement at a later point in time was evaluated with a time-lagged cross-correlational analysis, an application of causal modeling techniques. Longitudinal data for 32 males and females, tested in 1944 (mean age 19.5 years) and in 1972 (mean age 46.7 years), supported the hypothesized relationships with an associated p less than .01. The Relations Factor of the Army Alpha Examination--consisting of scores from a highly speeded simple analogies test and a short-term memory test--administered at age 20 was highly predictive of both verbal and numerical ability in middle age. The results highlight the cognitive intellectual aspect of the speed of behavior. In addition, these findings supplement Hunt's studies of the relationships between speed of cognitive processing and psychometric abilities in young adults, and emphasize the importance of cognitive speed for subsequent intellectual development. Implications for the intellectual speed hypothesis of Birren and the utilization of time-lag designs in longitudinal research are discussed.

Adult↗
PubMed1989

The role of microcomputers in electronic health claims processing.

This article explores the state-of-the-art in electronic health claims processing. Beginning with an examination of the step-by-step manual process, it moves on to explore the current use of microcomputers to both speed up the processing, and to improve the accuracy and completeness of claim submission. The article also examines some of the benefits cited by microcomputer claims systems users, and it concludes with a look at what features could be incorporated in the future to create a fully electronic claims processing environment.

Computer Communication Networks↗
PubMed1992

BIO-SPEAD: a parallel computing environment to accelerate development of biologic signal processing algorithms.

We have created BIO-SPEAD (pronounced speed), a BIOlogical Signal Processing Environment for Algorithm Development. BIO-SPEAD is designed to accelerate development of complex algorithms which integrate information derived from single or multiple physiologic waveforms. BIO-SPEAD currently performs all of the basic analyses of several arterial blood pressure waveforms, and allows the user to utilize the results of those low-level analyses for development of more complex algorithms. We utilized a parallel programming architecture called the Process Trellis which keeps the different tasks, or processes, within BIO-SPEAD independent of each other. Additionally, we have developed a graphics interface to enable the user to visualize the waveform under analysis, the low-level system analysis, and the internal workings of the algorithm under development. The system has been used for several algorithm development projects and has demonstrated its utility.

Algorithms↗
PubMed1996

Poor speed discrimination suggests that there is no specialized speed mechanism for cyclopean motion.

Luminance-defined and stereo-defined (cyclopean) motion share some common properties, suggesting that the two forms of motion may be detected by similar mechanisms. For luminance-defined motion there are at least two levels of processing: direction is detected and then speed is thought to be extracted by a specialized processing mechanism at a higher level. Here, we tested whether there is also a specialized speed processing mechanism for stereo-defined motion. Speed discrimination thresholds were compared for stimuli containing only stereo-defined motion, and stimuli that contained both stereo-defined and luminance-defined motion. When the stimulus contained luminance-defined motion, increment thresholds were around 0.05-0.1. For stereo-defined motion, increment thresholds were never better than 0.3. By careful analysis, it was possible to test what cues were being used to solve the speed discrimination task. Results were consistent with observers responding to distance cues rather than to speed for stereo-defined motion, suggesting that there is no specialized mechanism for processing the speed of stereo-defined motion.

Cues↗
PubMed2003

A brief neuropsychological testing battery for evaluating patients with schizophrenia.

Current conceptualizations of schizophrenia include neurocognitive impairment, particularly in aspects of attention, memory, and executive functioning. Evaluation of these cognitive abilities typically involves use of comprehensive batteries which may take up to six hours to complete. The current study examined the effectiveness of a briefer battery to detect cognitive impairments usually seen in schizophrenia as established by previous studies using more lengthy and labor intensive protocols. The current study involved 61 outpatients with schizophrenia who were separated into three subgroups: paranoid type (n = 20), undifferentiated type (n = 21), and schizoaffective (n = 20). The majority of the patients were male (61%), African-American (52%), and of low socio-economic status. The mean age was 41.4 years (SD = 8.8), and the mean years of education was 11.7 (SD = 6.8). For the overall sample, results revealed mild to moderate impairments in memory, construction, concept formation, response set maintenance, psychomotor speed, and visual speed of information processing. Post-hoc analyses revealed significant differences between subgroups on Similarities and psychomotor speed, with the undifferentiated group performing more poorly than the paranoid or schizoaffective groups. In conclusion, the current brief battery minimized respondent burden in terms of both time demands and level of task complexity. However, it was also sensitive enough to capture many of the same cognitive weaknesses as those reported when using more labor-intensive neuropsychological test protocols.

Adult↗
PubMed2005

Basal ganglia and language: phonology modulates dopaminergic release.

Basal ganglia have been implicated in syntactic and phonological processes, but direct evidence has been scarce. Here, we used [11C]raclopride and positron emission tomography to measure modulations of the dopaminergic system induced by phonological or syntactic processing. Two significant effects were found. First, the level of accuracy in phonological processing significantly correlated with tracer binding potential in the left caudate nucleus. Second, the speed in phonological processing significantly correlated with tracer binding potential in the left putamen. Thus, a more accurate and fast phonological processing was associated with a reduced dopamine requirement in the left striatum. These findings show that the striatal dopaminergic system plays an essential role in grammatical processes that form the core of human language.

Acoustic Stimulation↗
PubMed2004

Parallel versus serial processing and individual differences in high-speed search in human memory.

Many mental tasks that involve operations on a number of items take place within a few hundred milliseconds. In such tasks, whether the items are processed simultaneously (in parallel) or sequentially (serially) has long been of interest to psychologists. Although certain types of parallel and serial models have been ruled out, it has proven extremely difficult to entirely separate reasonable serial and limited-capacity parallel models on the basis of typical data. Recent advances in theory-driven methodology now permit strong tests of serial versus parallel processing in such tasks, in ways that bypass the capacity issue and that are distribution and parameter free. We employ new methodologies to assess serial versus parallel processing and find strong evidence for pure serial or pure parallel processing, with some striking apparent differences across individuals and interstimulus conditions.

Adult↗
PubMed2002

Are neuronal activity-associated magnetic fields the physical base for memory?

Despite intensive investigation into the mechanisms underlying the memory process, the physical bases for this superior cognitive function remain elusive. Recall of past events and actions depends on the generation of complex memory carriers that would have to integrate many items of information. Some human memory processes, like contextual recall, work at such high speed and integrate such a large number of cortical neurons and neuronal networks that molecular mechanisms of information storage and synaptic transmission seem insufficient. This limitation argues against molecular information storage mechanisms as being truly effective carriers for the memory process. In this paper, I propose that any type of information can be stored in the form of 'neuronal activity-associated magnetic fields' that would record information in much the same way as the magnetic tape of a tape recorder. Integration and/or combination of the neuronal activity-associated magnetic fields throughout the complex three-dimensional structure of the human cortex could provide a storage medium for high-speed processing and discrimination that would support the complexity of the human memory process.

Animals↗
PubMed2006

A phase-based stereo vision system-on-a-chip.

A simple and fast technique for depth estimation based on phase measurement has been adopted for the implementation of a real-time stereo system with sub-pixel resolution on an FPGA device. The technique avoids the attendant problem of phase warping. The designed system takes full advantage of the inherent processing parallelism and segmentation capabilities of FPGA devices to achieve a computation speed of 65megapixels/s, which can be arranged with a customized frame-grabber module to process 211frames/s at a size of 640x480 pixels. The processing speed achieved is higher than conventional camera frame rates, thus allowing the system to extract multiple estimations and be used as a platform to evaluate integration schemes of a population of neurons without increasing hardware resource demands.

Biomedical Engineering↗
PubMed2004

Evaluation and optimization of chromium removal from tannery effluent by microemulsion in the Morris extractor.

In this research a surfactant derived from a vegetable oil (coconut oil) was used to remove chromium from a tannery effluent. In the extraction process, a Morris extractor was used. Important variables used in assessing the optimization of the process included agitation speed, solvent rate and total flow rate. The experiments were conducted using a 2(3) factorial design. According to the response from the experimental design, the effects of each variable were calculated and the interactions between them determined. Response surface methodology was employed to study the effects of the studied variables. The optimum operational conditions were: agitation speed, 428 rpm; solvent rate, 0.37; total flow rate, 2.0 l h(-1). After extraction process, a re-extraction study was accomplished and the obtained results showed that chromium could be removed from the microemulsion phase by hydrochloric and sulphuric acidic solutions, what allows its reuse in the leather manufacturing process.

Algorithms↗