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PubMed1987

Coding of spatial location information: an automatic process?

Several researches have claimed that spatial location information is automatically encoded, a claim supported by studies testing several criteria for the identification of automatic processes. However, a careful look at these studies reveals that some have not used appropriate testing methodology, the results of others have not complied with the criteria, and some criteria have not been examined at all. This article includes four experiments in which five criteria for testing the automaticity of cognitive processes were examined. Results show that memory for spatial location information is influenced by intention, age of subjects, competing task loads, practice, strategy manipulations, and individual differences. These results generally hold for memory of absolute location and for relative location information. The reported results are at odds with the claim that memory for spatial location information is exclusively mediated by automatic encoding processes. The concept of automaticity and the appropriateness of the testing criteria are discussed in light of the current results and recent findings on other features of the environment claimed to be automatically encoded.

Adult↗
PubMed2003

Development of disposable self-regulating blood pumps and automatically-controlled portable extracorporeal membrane oxygenation systems for neonatal extracorporeal membrane oxygenation.

For safer and simpler neonatal ECMO management, the authors have been developing an innovative, automatically-controlled ECMO machine using self-regulating blood pumps. The newest model is an air-driven, tube-type blood pump. A pair of blood pumps are placed in parallel and actuated alternately with compressed air. The pump flow is automatically regulated in accordance with hemodynamic changes of the body. The need for a venous reservoir is eliminated because the circuit does not generate excessive negative pressure when there are shortages of draining blood. Therefore, the priming volume of the circuit is only 85 ml. This ECMO apparatus has three driving modes, one of which is a "delay" mode. This enables the pump flow to easily be varied from 10 to 500 ml/min under automatic control, and it can be used when the pump flow is decreased for weaning. This newest ECMO apparatus was clinically used in 3 neonates with severe lung hypoplasia and persistent fetal circulation. The ECMO duration was 139 h to 168 h, and the maximum ECMO flow 71.3 to 109.0 ml/min/kg. Thanks to the self-regulation, intensive observation of the circuit was not necessary during ECMO. Damage to blood cells was less significant, and the use of blood products was only minimal (15.7 ml/kg/day) because a large volume of blood to stabilize the pump performance was not necessary. In conclusion, the automatically-controlled ECMO apparatus worked well without complications by changing the ECMO flow automatically in accordance with hemodynamic changes. This automatic ECMO system required fewer personnel expenditures and was also favorable in terms of hematological findings.

Acute Disease↗
PubMed1983

Efficiency of automatic depth in processing in the elderly.

Initial encoding of information in the elderly was examined within the framework of controlled vs automatic processing. Controlled processing demands conscious effort, whereas automatic processing is cost-free in this regard. The suggestion is that adequate encoding and storage could be hindered if semantic depth is not accessed automatically. A task developed by Warren to investigate automatic processing in young Ss was used to test whether words reached semantic levels automatically in elderly Ss. Twenty-four females, 12 young and 12 old, heard word triads. Each triad was followed by visual presentation of a single word in colored ink. For both young and old Ss, color-naming latency for the visual words was significantly higher if the word itself was present in the auditory triad. This indicated that the visual words were processed to the level of meaning automatically in both young and old Ss.

Adult↗
PubMed1992

Noninvasive automatic blood pressure monitoring does not attenuate nighttime hypotension. Evidence from 24 h intraarterial blood pressure monitoring.

Automatic ambulatory blood pressure monitoring makes use of repeated cuff inflations throughout the day and night. This may interfere with the cardiovascular effects of sleep and thus alter the 24 h blood pressure profile. The possibility that intermittent automatic blood pressure measurements prevent nocturnal hypotension was examined in 17 mild or moderate essential hypertensive patients in whom blood pressure was recorded intraarterially for 48 h by the Oxford technique. During the first or the second 24 h period, blood pressure was also monitored noninvasively by the SpaceLabs (Redmond, WA) 5300 (n = 10) and by the Sandoz Pressure System SPS 1558 (Lavanchy Electronique, Prilly, Switzerland) (n = 7) devices, automatic measurements being performed at 15 min intervals during the day and at 30 min intervals during the night. Separate computer analysis of 24 h intraarterial tracings obtained in absence and in concomitance of contralateral automatic blood pressure monitoring showed that the occurrence of automatic measurements had not interfered with the day-night intraarterial blood pressure and heart rate profiles. Thus the frequent cuff inflations that characterize automatic blood pressure monitoring do not attenuate nighttime hypotension and bradycardia. This finding supports use of the noninvasive approach in assessing blood pressure profiles.

Adult↗
PubMed2001

Cardiorespiratory effects of automatic tube compensation during airway pressure release ventilation in patients with acute lung injury.

BACKGROUND: Spontaneous breaths during airway pressure release ventilation (APRV) have to overcome the resistance of the artificial airway. Automatic tube compensation provides ventilatory assistance by increasing airway pressure during inspiration and lowering airway pressure during expiration, thereby compensating for resistance of the artificial airway. The authors studied if APRV with automatic tube compensation reduces the inspiratory effort without compromising cardiovascular function, end-expiratory lung volume, and gas exchange in patients with acute lung injury. METHODS: Fourteen patients with acute lung injury were breathing spontaneously during APRV with or without automatic tube compensation in random order. Airway pressure, esophageal and abdominal pressure, and gas flow were continuously measured, and tracheal pressure was estimated. Transdiaphragmatic pressure time product was calculated. End-expiratory lung volume was determined by nitrogen washout. The validity of the tracheal pressure calculation was investigated in seven healthy ventilated pigs. RESULTS: Automatic tube compensation during APRV increased airway pressure amplitude from 7.7+/-1.9 to 11.3+/-3.1 cm H2O (mean +/- SD; P < 0.05) while decreasing trans-diaphragmatic pressure time product from 45+/-27 to 27+/-15 cm H2O x s(-1) x min(-1) (P < 0.05), whereas tracheal pressure amplitude remained essentially unchanged (10.3+/-3.5 vs. 10.1+/-3.5 cm H2O). Minute ventilation increased from 10.4+/-1.6 to 11.4+/-1.5 l/min (P < 0.001), decreasing arterial carbon dioxide tension from 52+/-9 to 47+/-6 mmHg (P < 0.05) without affecting arterial blood oxygenation or cardiovascular function. End-expiratory lung volume increased from 2,806+/-991 to 3,009+/-994 ml (P < 0.05). Analysis of tracheal pressure-time curves indicated nonideal regulation of the dynamic pressure support during automatic tube compensation as provided by a standard ventilator. CONCLUSION: In the studied patients with acute lung injury, automatic tube compensation markedly unloaded the inspiratory muscles and increased alveolar ventilation without compromising cardiorespiratory function and end-expiratory lung volume.

Adult↗
PubMed1988

Effects of procainamide on automatic and triggered impulse initiation in isolated preparations of canine cardiac Purkinje fibers.

The effects of procainamide (40 mg/L) were studied on automatic and triggered impulse initiation in isolated preparations of canine cardiac Purkinje fibers using standard microelectrode techniques. Procainamide decreased normal automaticity by 48% in Purkinje fibers superfused with standard (KCl 4 mM) Tyrode's solution. In contrast, procainamide decreased the rate of normal Purkinje fibers that had been treated with isoproterenol (1 microM) by only 6% (NS). For comparison, the effects of lidocaine (4 mg/L) and quinidine (5 mg/L) were studied on isoproterenol-treated fibers. Lidocaine and quinidine both significantly decreased the isoproterenol-enhanced rate of normal automaticity (by 45 and 10%, respectively). In studies of the effects of procainamide on Purkinje fibers with abnormal automaticity (i.e., the pacemakers had maximal diastolic potentials less than -60 mV), it was found that drug treatment decreased the rate of 24 h infarct zone Purkinje fibers by 22% and barium chloride (250 microM) treated Purkinje fibers by 51%. In studies of another five infarct zone preparations, the Purkinje fibers had maximal diastolic potentials greater than -75 mV and showed triggered activity with delayed afterdepolarizations. Procainamide decreased the triggered activity in only one of these preparations. Ventricular tachycardias that respond to procainamide may be caused by abnormal automaticity, whereas procainamide refractory tachycardias may result from triggered activity or from catecholamine-enhanced normal automaticity.

Action Potentials↗
PubMed1998

Evaluation of left ventricular volume using automatic border detection in children: a comparison with conventional off-line echocardiographic quantification.

BACKGROUND: Evaluation of the clinical usefulness of the one-line automatic border detection system for determination of left ventricular volume in children in comparison to the conventional off-line method. METHODS: Eighty consecutive patients in whom clear images were obtained by two-dimensional echocardiography were studied. Using the Hewlett-Packard Sonos 2500 with a 3.5 or 5.5 Mhz phased array transducer, all patients were studied in the apical four-chamber imaging plane for automatic border detection and apical four-chamber and two-chamber imaging planes for manual tracing. Left ventricular end-diastolic and end-systolic volumes were measured and compared using the bi-plane Simpson method. RESULTS: Left ventricular end-diastolic volumes obtained by automatic border detection correlated well but were slightly underestimated compared to those obtained by manual tracing (r = 0.98). Left ventricular end-systolic volumes obtained by automatic border detection also correlated well with those obtained by manual tracing (r = 0.96). Left ventricular ejection fractions compared favorably. However, left ventricular volumes obtained using the classical Pombo M-mode echocardiography showed poorer correlation with those obtained by manual tracing methods. CONCLUSIONS: Automatic border detection is a promising method for real-time estimation of left ventricular volume. In patients with good endocardial tracking, automatic border detection can be used for routine studies of cardiovascular disease, even in children.

Adolescent↗
PubMed1995

Automatic needle insertion diminishes pain during growth hormone injection.

Non-compliance in children receiving growth hormone (GH) treatment is often caused by pain on injection and difficulties in administration of GH. It has been suggested that automatic needle insertion diminishes pain perception. We quantitatively measured pain intensity on injection with two prototype pens for GH administration, providing either manual or automatic sc needle insertion, using a combined visual analogue/facial scale and a five-item scale in 18 children. With the automatic pen there was a significantly lower maximum pain score compared with the manual pen (median 28.5 versus 52.0 mm) as well as a lower mean pain score (mean 13.7 versus 23.5 mm). The five-item scale revealed that automatic needle insertion was significantly less painful than manual insertion and 13 patients chose to continue treatment with the automatic pen. In conclusion, pain during GH injection can be significantly diminished by automatic needle insertion, which may improve compliance in long-term GH treatment.

Adolescent↗
PubMed1980

Physiological role of endogenous amines in the modulation of ventricular automaticity in the guinea-pig.

1. Current-clamp experiments were carried out with guinea-pig papillary muscles to determine the dependence of depolarization-induced automaticity on endogenous catecholamines. 2. Catecholamine depletion was produced by pre-treatment of animals with 6-hydroxydopamine and confirmed by fluorimetric assay of right ventricular tissue. Papillary muscles from depleted animals demonstrated a marked suppression of depolarization-induced automaticity for maximum diastolic potentials less negative than -55 mV. This suppression was completely reversed by noradrenaline but not by tyramine. 3. In normal tissue, noradrenaline and tyramine had much smaller effects on automaticity arising from maximum diastolic potentials negative to -55 mV than on repetitive activity arising positive to this level. 4. L-propranolol in concentrations of 2-3 x 10(-7) M reduced repetitive activity in the less negative range of maximum diastolic potential. No evidence of direct membrane depression was observed at these doses and the effect was reversed by application of noradrenaline. 5. D-propranolol, the isomer with much lower beta-receptor blocking potency, required twentyfold higher concentrations to depress automaticity and this was accompanied by evidence of direct membrane depression, i.e. reduction of upstroke velocity of action potentials. 6. These results show that automaticity induced in guinea-pig papillary muscles by depolarization positive to -55 mV is strongly dependent upon endogenous catecholamines. 7. The hypothesis that endogenous catecholamines facilitate depolarization-induced automaticity through an increase in calcium conductance was modelled using numerical techniques. It was found that changes in calcium conductance caused changes in the model which closely parallelled the experimental effects of catecholamine depletion and beta-blockade. The effects of changes in delayed rectification in the model did not accurately reproduce the experimental results.

Animals↗
PubMed1998

Automatic full field analysis of perfusion images gained by scanning laser Doppler flowmetry.

BACKGROUND: Scanning laser Doppler flowmetry (SLDF) enables the measurement of the laser Doppler frequency shift in retinal tissue. This process allows the quantification of retinal and optic nerve head perfusion in an area of 2.7 mm x 0.7 mm within 2 seconds and with a spatial resolution of 10 microns x 10 microns. Owing to the local heterogeneity of the retinal microcirculation itself and to heart associated pulsation the capillary retinal blood flow depends on location and time. Because of technical limitations measurements of flow are only valid in retinal points with adequate brightness and focus, and away from big vessels. To include the heart beat associated pulsation and the spatial heterogeneity of retinal blood flow into the evaluation of blood flow an algorithm was developed examining automatically the whole SLDF perfusion image. AIM: To report intraobserver reliability and interobserver reliability of a new method for analysing automatically full field perfusion images. METHOD: The base of blood flow calculation by the automatic full field perfusion image analyser (AFFPIA) was 16,384 intensity time curves of all pixels of the whole perfusion image gained by the SLDF. AFFPIA calculates the Doppler frequency shift and the haemodynamic variables flow, volume, and velocity of each pixel. The resulting perfusion image was processed with respect to (1) underexposed and overexposed pixels, (2) saccades, and (3) the retinal vessel tree. The rim area and the saccades were marked interactively by the operator. The capillaries and vessels of the retinal vessel tree were identified automatically by pattern analysis. Retinal vessels with a diameter greater than 30 microns, underexposed or overexposed areas, and saccades were excluded automatically. Based on the whole perfusion image total mean flow, total mean volume, total mean velocity, standard deviation, cumulative distribution curve of flow, and the capillary pulsation index were calculated automatically. Heart beat associated pulsation of capillary blood flow was estimated by plotting the mean capillary flow of each horizontal line against time. Intraobserver reliability was estimated by measuring 10 eyes of 10 subjects on five different days by one observer. Interobserver reliability of AFFPIA was evaluated by analysing 10 perfusion maps by five different operators. To find a baseline of retinal blood flow, perfusion maps of 67 eyes of normal subjects with a mean age of 40.4 (SD 15) years were evaluated by AFFPIA. RESULTS: The coefficient of reliability of the intraobserver reproducibility of flow was 0.74. The coefficient of reliability of the interobserver reproducibility was 0.95. The juxtapapillary retinal capillary flow was temporally 484 (SD 125), nasally 450 (117); the rim area capillary flow was 443 (110). The mean capillary pulsation index of retinal flow was 0.56 (0.14). CONCLUSION: Retinal blood flow evaluation by the AFFPIA increases significantly the interobserver reliability compared with conventional evaluation of 100 microns x 100 microns areas in SLDF images with the original Heidelberg retina flowmeter software. The intraobserver reliability of AFFPIA was in the same range as conventional evaluation.

Adult↗
PubMed1996

Accuracy of four automatic QT measurement techniques in cardiac patients and healthy subjects.

OBJECTIVE: To assess differences in the accuracy of automatic QT measurement in three subject groups, and to determine the influence of T wave amplitude on these measurements. SUBJECTS: Standard simultaneous 12 lead electrocardiograms were acquired from 25 patients post myocardial infarction, 25 with arrhythmias, and 25 controls. DESIGN: Because there is not yet a standard automatic method for QT analysis, four different techniques were used. Manual QT measurements were used as the reference. QT was measured in two complexes by each technique in each lead, subject, and group. MAIN OUTCOME MEASURE: The differences between reference and automatic QT measurements from the three subject groups were compared independently for the four techniques. The T wave amplitudes for each of the groups were also compared. RESULTS: Variability of the automatic QT measurements, relative to the manual reference, in the cardiac patients was 2.1 times that in the controls (P < 0.005). Mean T wave amplitude was lower (by a factor of two) for the cardiac patients compared with the controls (P < 0.01). No simple relation between T wave amplitude and the difference between automatic and manual QT measurements was found, although the difference was 2.2 times greater for absolute T wave amplitudes of less than 0.25 mV (P < 0.001). CONCLUSIONS: Automatic QT measurement techniques are less accurate in cardiac patients than in controls. Measurements from T waves with amplitudes less than 0.25 mV are less reliable.

Arrhythmias, Cardiac↗
PubMed1986

Enhancement by norepinephrine of automaticity in sheep cardiac Purkinje fibers exposed to hypoxic glucose-free Tyrode's solution: a role for alpha-adrenoceptors?

A period of drive in the presence of norepinephrine (NE) may be followed by the induction or acceleration of spontaneous activity. Experiments were carried out in sheep cardiac Purkinje fibers to determine whether the effects of NE on automaticity were modified during superfusion with hypoxic glucose-free Tyrode's solution and to assess the possible contribution of alpha-adrenergic influences on automaticity under these conditions. The following results were obtained: Low concentrations of NE (10(-7) and 3 X 10(-7)M) were able to induce automaticity after a period of drive in normal oxygenated (97% O2, 3% CO2) Tyrode's solution. Superfusion with hypoxic (97% N2, 3% CO2) glucose-free Tyrode's solution enhanced NE-induced automaticity. Practolol, in concentrations able to block the effects of NE in normal oxygenated solution, did not counteract the effects of NE in hypoxic glucose-free solution. Yohimbine, but not prazosin, antagonized the effects of NE in hypoxic glucose-free solution. At the same concentration, yohimbine did not affect transmembrane potentials or automaticity induced by isoproterenol. It is concluded that alpha-adrenergic responsiveness appears to be enhanced during superfusion in vitro with hypoxic glucose-free solution, and that alpha-adrenoceptors belonging to the alpha 2-subtype in sheep cardiac Purkinje fibers might influence abnormal automaticity, possibly through an effect on oscillatory potentials.

Animals↗
PubMed1987

Automaticity, triggered activity, and responses to adrenergic stimulation in cat subendocardial Purkinje fibers after healing of myocardial infarction.

We studied automaticity, triggered activity, and responses to alpha- and beta-adrenergic stimulation in subendocardial Purkinje fibers overlying healed infarct scars (infarct preparation) and from remote normal zones (noninfarct preparation) of cat left ventricles. The preparations were studied 2 to 4 months after ligation of multiple distal tributaries of the left anterior descending and circumflex arteries. Subendocardial Purkinje fibers from corresponding areas of normal hearts served as control samples (control preparation). Transmembrane action potential characteristics and rates of automaticity (spontaneous phase 4 depolarization) did not differ among control, noninfarct, and infarct preparations. However, overdrive at cycle lengths of less than 400 msec suppressed automaticity to a greater degree in Purkinje fibers of infarct preparations than those of control and noninfarct preparations. Changes in automatic rate during superfusion with isoproterenol (10(-10)M to 10(-6)M) were not different among the three groups of preparations, but exposure to phenylephrine (10(-9)M to 10(-5)M) in the presence of 5 X 10(-7)M propranolol reduced the automatic rate to a greater degree in Purkinje fibers of infarct preparations than those of control or noninfarct preparations. Triggered activity arising from delayed afterdepolarizations was recorded in 10 of 29 infarct preparations (34%), but not in 12 control and 10 noninfarct preparations. These afterpotentials were augmented by increasing extracellular Ca++ concentration, 10(-7)M isoproterenol, and 10(-5)M phenylephrine in the presence of 5 X 10(-7)M propranolol. We conclude that Purkinje fibers overlying healed infarct scars have altered physiology of spontaneous automaticity, enhanced responses to alpha-adrenergic interventions, and a tendency to triggered activity, and that both alpha- and beta-adrenergic effects may result in worsening of arrhythmias by augmentation of afterpotentials in healed myocardial infarction.

Action Potentials↗
PubMed1988

Automatic and triggered impulse initiation in canine subepicardial ventricular muscle cells from border zones of 24-hour transmural infarcts. New mechanisms for malignant cardiac arrhythmias?

With standard microelectrode techniques, electrical activity of cells in the epicardial border zones of infarcts in the canine heart were studied. Either automaticity or triggered activity (or both) occurred in each of the 12 preparations studied from 24-hour infarcts. One 24-hour preparation had continuous activity indistinguishable from low-potential (abnormal) automaticity. This automaticity was not effected by flecainide 1-5 mg/l. Two other 24-hour subepicardial muscle preparations also were automatic. However, nine preparations from the subepicardium were not automatic during superfusion with standard Tyrode's solution. Delayed afterdepolarizations (DADs) and triggered activity could be induced in all of these preparations by treatment with catecholamines. The amplitude of these DADs was directly related to the stimulus rate of the train of impulses used to elicit them, and their coupling interval was inversely related to this rate of stimulation. Triggered activity occurred from maximal diastolic potentials of -58 to -88 mV in the 24-hour infarct zone preparations. In seven preparations from 72-96-hour infarct zones, the epicardial muscle cells did not show triggered activity after treatment with catecholamines. In one preparation from a 72-hour infarct, however, 3-5-mV DADs occurred. No DADs or triggered impulses occurred in subepicardial muscle from normal, noninfarcted hearts. Thus, triggered impulses and low-potential automaticity could contribute to arrhythmias occurring in the canine heart 24 hours after coronary ligation.

Animals↗
PubMed2004

Automatic control of the inspired oxygen fraction in preterm infants: a randomized crossover trial.

In preterm infants receiving supplemental oxygen, manual control of the inspired oxygen fraction is often time-consuming and inappropriate. We developed a system for automatic oxygen control and hypothesized that this system is more effective than routine manual oxygen control in maintaining target arterial oxygen saturation levels. We performed a randomized controlled crossover clinical trial in 12 preterm infants receiving nasal continuous positive airway pressure and supplemental oxygen. Periods with automatic and routine manual oxygen control were compared with periods of optimal control by a fully dedicated person. The median (range) percentage of time with arterial oxygen saturation levels within target range (87-96%) was 81.7% (39.0-99.8) for routine manual oxygen control, 91.0% (41.4-99.3) for optimal control, and 90.5% (59.0-99.4) for automatic control (ANOVA: p = 0.01). Pairwise post hoc comparisons revealed a statistically significant difference between automatic and routine manual oxygen control (Dunnett's test: p = 0.02). The frequency of manual oxygen adjustments was lowest in automatic control (Friedman's test: p < 0.001). Automatic oxygen control may optimize oxygen administration to preterm infants receiving nasal continuous positive airway pressure and reduce nursing time spent with oxygen control.

Automation↗
PubMed1996

Visual and different automatic scoring profiles of respiratory variables in the diagnosis of sleep apnoea-hypopnoea syndrome.

The purpose of our study was to explore the diagnostic accuracy of different methods of scoring night time recording of respiratory variables (NTRRV) for the diagnosis of the sleep apnoea-hypopnoea syndrome (SAHS). Within a 2 week period, we performed a partially attended night time recording of respiratory variables and a full polysomnography (PSG) for reference in patients with suspected SAHS. Night time recording of respiratory variables was carried out using equipment which records, and continuously displays on a monitor, oximetry, airflow, chest and abdominal motion and body position. Night time recording of respiratory variables was scored manually and automatically, according to different combinations of the parameters described previously. Full polysomnography was performed in the Sleep Laboratory following conventional standards. Thirty six patients were studied. Visual analysis and different automatic scoring profiles of night time recording of respiratory variables were compared to full polysomnography in terms of agreement, sensitivity and specificity. Visual scoring of night time recording of respiratory variables gave the finest agreement-sensitivity-specificity relationship. Automatic scoring of nighttime recording of respiratory variables showed a trend to underestimate the apnoea-hypopnoea index (AHI) with respect to full polysomnography due mainly to underrecognition of hypopnoeas. Agreement-sensitivity-specificity relationships of automatic night time recording of respiratory variables with respect to full polysomnography varied depending on the automatic profile used. Some had a good agreement and sensitivity whilst others had a good specificity. These findings show that visual scoring of night time recording of respiratory variables is the most accurate method of analysis when compared to full polysomnography. The usefulness of the automatic methods of scoring of respiratory variables depends on the end-point chosen and is not reliable enough to be used in all situations. Night time recording of respiratory variables represents a real complement to conventional full polysomnography in clinical practice.

Adult↗
PubMed2006

Automatic pathway building in biological association networks.

BACKGROUND: Scientific literature is a source of the most reliable and comprehensive knowledge about molecular interaction networks. Formalization of this knowledge is necessary for computational analysis and is achieved by automatic fact extraction using various text-mining algorithms. Most of these techniques suffer from high false positive rates and redundancy of the extracted information. The extracted facts form a large network with no pathways defined. RESULTS: We describe the methodology for automatic curation of Biological Association Networks (BANs) derived by a natural language processing technology called Medscan. The curated data is used for automatic pathway reconstruction. The algorithm for the reconstruction of signaling pathways is also described and validated by comparison with manually curated pathways and tissue-specific gene expression profiles. CONCLUSION: Biological Association Networks extracted by MedScan technology contain sufficient information for constructing thousands of mammalian signaling pathways for multiple tissues. The automatically curated MedScan data is adequate for automatic generation of good quality signaling networks. The automatically generated Regulome pathways and manually curated pathways used for their validation are available free in the ResNetCore database from Ariadne Genomics, Inc. 1. The pathways can be viewed and analyzed through the use of a free demo version of PathwayStudio software. The Medscan technology is also available for evaluation using the free demo version of PathwayStudio software.

Databases, Bibliographic↗
PubMed2000

Activation of language cortex with automatic speech tasks.

OBJECTIVE: To identify automatic speech tasks that reliably demonstrate increased regional cerebral blood flow (rCBF) in Broca's and Wernicke's areas of the cortex using PET. BACKGROUND: Localizing language with direct cortical stimulation mapping requires that patients have a stable baseline on tests that engage eloquent cortex. For dysphasic patients or younger children, automatic speech tasks such as counting are often used in lieu of more complex language tests. Evidence from both lesion and neuroimaging studies suggests that these tasks may not adequately engage language cortices. In this study, we examined rCBF during automatic oromotor and speech tasks of varying complexity to identify those eliciting increased CBF in Broca's and Wernicke's areas. METHODS: Eight normal volunteers underwent PET during rest, tongue movements, and three automatic speech tasks: repeating a phoneme sequence, repeating the months of the year, and reciting a memorized prose passage. Images were averaged across subjects and compared across tasks for regional localization and laterality. RESULTS: Whereas all activation tasks produced increased relative CBF in brain regions that correlated with articulation and auditory processing, only the two tasks that used real words (versus phonemes) showed left-lateralized rCBF increases in posterior superior temporal lobe (Wernicke's area), and only the prose repetition task produced left lateralized activity in Broca's area. CONCLUSIONS: Whereas automatic speech typically does not engage language cortex, repeating a memorized prose passage showed unambiguous activation in both Broca's and Wernicke's areas. These results caution against the use of common automatic speech tasks for mapping eloquent cortex and suggest an alternative task for those with poor language abilities or acquired dysphasia who cannot perform standardized language tests reliably.

Adult↗