Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Automatism”

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 1,153 records · Page 64Linked to original sources
PubMed1997

Automatic annotation for biological sequences by extraction of keywords from MEDLINE abstracts. Development of a prototype system.

We have developed a prototype for the automatic annotation of functional characteristics in protein families. The system is able to extract biological information directly from scientific literature in the form of MEDLINE abstracts. The criterion for selecting relevant keywords is the difference between their frequency in the abstracts associated with the protein family under study and its frequency in other unrelated protein families. The concept of functional information associated to protein families is the key feature of our system and gathers evolutionary information into the problem of functional annotation of biological sequences. The system has been tested in two different scenarios: first, a large set of protein families with a small number of abstract per family and second, selected protein families with large number of abstracts attached to each one. In both cases the performances are compared with annotations provided by human experts showing a clear relation between the amount of information provided to the system and the quality of the annotations. The automatic annotations are in many cases of similar quality to the ones contained in current data bases. The possibilities and difficulties to be encountered during the development of a full system for automatic annotation are discussed.

Abstracting and Indexing↗
PubMed1997

Automatic construction of knowledge base from biological papers.

We designed a system that acquires domain specific knowledge from human written biological papers, and we call this system IFBP (Information Finding from Biological Papers). IFBP is divided into three phases, Information Retrieval (IR), Information Extraction (IE) and Dictionary Construction (DC). We propose a query modification method using automatically constructed thesaurus for IR and a statistical keyword prediction method for IE. A dictionary of domain specific terms, which is one of the central knowledge sources for the task of knowledge acquisition, is also constructed automatically in the DC phase. IFBP is currently used for constructing the Transcription Factor DataBase (TFDB) and shows good performance. Since the model of knowledge base construction that is adopted into IFBP is carried out entirely automatically, this system can be easily ported across domains.

Algorithms↗
PubMed1998

Contributions of the dopaminergic system to voluntary and automatic orienting of visuospatial attention.

Visuospatial attention can be directed by voluntary or involuntary control independent of eye movement. The involvement of cortical and subcortical neural structures in this covert orienting mechanism has been studied using neuroimaging and electrophysiological techniques. This study was designed to investigate the role of the dopaminergic system in both voluntary and automatic orienting mechanisms of visuospatial attention. We recorded event-related evoked potentials (ERPs) and reaction time (RT) during a cued priming task in both patients with idiopathic Parkinson's disease (PD) and control subjects. Voluntary and automatic shifts in attention were studied by using central and peripheral cues, respectively. In the experiment using a central cue, the RT data showed that when the cue-target interval was long, PD patients' responses were delayed, and cue validity effects were reduced, whereas in the peripheral cue experiment the validity effects persisted across all trials. The ERPs demonstrated reduced sustained negativities preceding the imperative targets in both the central and peripheral cue experiments in PD patients. Furthermore, during the long cue-target interval in the central cue experiment, PD patients showed reduced attention shift-related negativities (ARNs) at the anterior scalp sites, whereas ARNs were generated widely in the peripheral cue experiment. The ERP findings were consistent with the RT data. These findings suggest that the dopaminergic system may contribute to voluntary and sustained control of visuospatial attention as well as to the neural system for response preparation, whereas automatic control of visuospatial attention is relatively independent of the dopamine system.

Aged↗
PubMed1976

[Automatic activity of pacemaker cells in the atrioventricular valves of the rabbit heart].

The microelectrode technique applied revealed an automatic activity of the pacemaker cells with slow diastolic depolarization in the cusps of the atrioventricular valves obtained from 34 rabbit hearts. Electrophysiological characteristics of the action potentials of these cells were investigated. Inhibitors of slow sodium-calcium canal (Mn++, Co++, and Mg++ ions) proved to eliminate the automatic activity of the pacemaker cells. When the content of potassium ions was elevated in the perfusion solution, no suppression occurred. It is suggested that the automatic activity of the pacemaker cells in the atrioventricular values depended mainly on the functioning of the slow sodium-calcium canal.

Action Potentials↗
PubMed1997

[Stochastic relations between conscious and automatic memory processes: an expansion of the process-dissociation procedure].

This paper presents an extension of the process dissociation procedure with wordstem completion, allowing the measurement of the stochastic relation between conscious and automatic processes. The conditional probabilities of conscious remembering with and without automatic processes can be determined. The determination of these conditional probabilities succeeds due to the extension of the process dissociation procedure by an indirect wordstem completion test, without referring to the usual assumptions of the dissociation paradigm. For the evaluation of this extended process dissociation procedure a multinomial model is presented which allows the distinction between voluntary and involuntary conscious memory. The model is applied to a study by ourselves and to an experiment published by Toth, Reingold, and Jacoby (1994). The results show that the assumptions of stochastic independence or redundancy as well as exclusivity of conscious and automatic processes are often violated. Two conscious processes with different probabilities of occurrence are found; voluntary and involuntary conscious memory processes.

Awareness↗
PubMed1998

Automatic three-dimensional matching of CT-SPECT and CT-CT to localize lung damage after radiotherapy.

UNLABELLED: The aim of this study was to develop a fast and clinically robust automatic method to register SPECT and CT scans of the lungs. METHODS: CT and SPECT scans were acquired in the supine position from 20 patients with healthy lungs. After partial irradiation of the lungs by radiotherapy, the scans were repeated. Two matching methods were compared: a conventional method with external skin markers and a new method using chamfer matching of the lung contours. In the latter method, a unique value for the SPECT threshold, needed for segmentation of the SPECT lungs, was determined by iteratively applying the chamfer matching algorithm. RESULTS: The new technique for CT-SPECT matching could be implemented in a fully automatic manner and required less than 2 min. No large systematic shifts or rotations were present between the matches obtained with the marker method and the lung contour method for healthy or partially irradiated lungs. For healthy lungs, the number of ventilation SPECT counts outside the CT-defined lung was taken as a measure for a good match. This number of outside counts was slightly lower for the new method than for the conventional method, which indicates that the accuracy of the new method is at least comparable to the conventional method. For ventilation, a systematic difference between the results of the matching methods, a small translation in the anterior --> posterior direction, could be attributed to an inconsistency of the marker positions (2 mm). For perfusion, a somewhat larger anterior --> posterior shift was found, which was attributed to the gravity force. CT-CT correlation on the lung contours using chamfer matching was tested with the same dataset. For accurate matching, the CT slices encompassing the diaphragm had to be deleted. CONCLUSION: The new method based on lung contour matching is a fast, automatic procedure and allows accurate clinical follow-up.

Humans↗
PubMed1998

[The concurrent implantation of a last-generation automatic defibrillator and a 2-chamber pacemaker].

BACKGROUND: Potentially lethal interactions between concomitantly implanted pacemaker and automatic first-generation cardioverter-defibrillator have been reported. We therefore evaluated the reliability and safety of simultaneous implantation of dual-chamber pacemakers with a fourth generation cardioverter-defibrillator incorporating an improved arrhythmia detection system. METHODS: Concomitant implantation of an automatic cardioverter defibrillator and a dual-chamber pacemaker was performed in four patients for malignant tachyarrhythmias and symptomatic bradycardia. Two Jewel 7219C and two Micro Jewel 7223 (Medtronic Inc.) implantable cardioverter defibrillators were connected to an endocardial lead (Medtronic Mod. 6936). In 2 patients with a previously implanted cardioverter-defibrillator, the pacemaker was connected to bipolar atrial and ventricular leads. In the 2 patients who already had a dual-chamber pacemaker, the unipolar pacing leads implanted previously were used. At the time of implantation of the second device, interaction testing was performed evaluating ventricular fibrillation detection during high-output asynchronous pacing. Testing for malfunctions, reprogramming or variations of pacing thresholds of the pacemakers after electric shocks was also carried out. Moreover, intracavitary signals, stimulation thresholds and electrical therapies delivered were evaluated during follow-up. RESULTS: During interaction testing, induced ventricular fibrillation was detected, with no delay, in 4/4 cases (100%). After a mean follow-up of 6.3 +/- 5 months (range 2-13), 5 shocks for ventricular fibrillation, 10 shocks for fast ventricular tachycardia and 72 antitachycardia pacings were delivered. All these electrical therapies were considered appropriate. No symptomatic sustained tachyarrhythmia remained undetected. CONCLUSIONS: These data suggest that concomitant implantation of a fourth-generation automatic cardioverter-defibrillator and a dual-chamber pacemaker using either unipolar or bipolar leads can be performed safely. Extreme caution and rigorous interactions testing is nevertheless advised when considering this device combination.

Aged↗
PubMedDate not supplied

Laparoscopic hysterectomy with automatic stapling devices.

PURPOSE: To evaluate outcomes including operating time, blood loss, length of stay (LOS), return to work and complications of laparoscopic hysterectomy performed with automatic stapling devices. METHODS: Between 6/11/91 and 11/23/95, 127 laparoscopic hysterectomies were performed with automatic stapling devices. On an average, 6 firings with the stapler were done per case. Postoperative telephone survey and retrospective review of records were done. RESULTS: Data averages for operating time, blood loss, LOS and return to work, respectively, were 90 minutes, 190 cc's, 1.1 day and 2 weeks. Significant complications included delayed postoperative bleeding in 4 patients, all of which occurred within the first 35 cases. One was controlled laparoscopically and 3 others required exploratory laparotomies. Since certain precautionary measures as described were taken, hemorrhagic complications were eliminated. CONCLUSIONS: Laparoscopic hysterectomy can be performed safely and effectively with automatic stapling devices in properly selected patients. A potential hazard inherent with this technique includes intraoperative and postoperative bleeding from the staple lines, the incidence of which can be minimized by taking certain precautionary measures such as the use of white cartridges only and bipolar desiccation of staple lines when indicated.

Adult↗
PubMed1958

Some observations on cardiac automatism in certain animals.

Certain aspects of the acetylcholine hypothesis of cardiac automaticity have been tested in vitro with spontaneously beating cardiac tissue from rabbits, rats, dams, and hagfish. The beat of atria from rabbits and rats may be depressed or excited by acetylcholine, depending upon the state of the tissue. Proguanil and cocaine inhibition of the beat in the rat may be antagonized by acetylcholine so that reversal of the depression occurs. The action of acetylcholine on the hearts of clams was found to be strictly inhibitory. Proguanil and cocaine, in contrast to their action on mammalian atria, exert a stimulatory effect on the heart of the molluscs studied. In fact, cocaine stimulated these hearts when they were inhibited by acetylcholine. Studies on the non-innervated hagfish heart revealed that this tissue is completely insensitive to the action of acetylcholine. Extracts prepared from beating hearts of this species will accelerate hypodynamic hearts of the hagfish as well as of the mussel. An extract of the neurogenic lobster heart was without effect on the hagfish heart. Proguanil was likewise ineffective in concentrations which produced inhibition and excitation in rat and clam hearts respectively. It was concluded that acetylcholine does not play a role in the myogenic automatism of all species, and that another mechanism is responsible is suggested on the basis of results obtained in the hagfish hearts.

Acetylcholine↗
PubMed1980

Violent automatism in a partial complex seizure. Report of a case.

We describe a patient who had a violent automatism that occurred during a partial complex seizure. The initial spike wave activity was recorded from nasopharyngeal leads that were lost as the patient began his vigorous, violent activity. This activity included nondirected, automatic, stereotyped behavior with physical assaults on objects in his path.

Adult↗
PubMed2006

Unimpaired automatic processing of verbal information in the course of clinical depression.

In this study automatic processing of verbal information was investigated in 22 clinically depressed inpatients and 22 healthy controls in a longitudinal design. A semantic priming task with word pronunciation was administered twice, about 7 weeks apart. Following brief presentations of prime words, subjects had to read target words aloud as quickly as possible. Prime words were directly related, indirectly related, or unrelated to the target words. Stimulus onset asynchrony (SOA) of prime and target was 250 ms. In the course of inpatient treatment, patients recovered significantly. Semantic priming occurred in both study groups for the directly and indirectly related conditions across both testing times. As expected, directly related primes resulted in stronger priming than indirectly related primes. Patients and controls did not differ in semantic priming at either time or relatedness condition. Size of priming was not associated with depression severity, anxiety level, intelligence, medication, or clinical features. We conclude that depression is not characterized by dysfunctional automatic processing of verbal information.

Adult↗
PubMed1997

Semantic priming in Broca's aphasics at a short SOA: no support for an automatic access deficit.

This study tests the recent claim that Broca's aphasics are impaired in automatic lexical access, including the retrieval of word meaning. Subjects are required to perform a lexical decision on visually presented prime target pairs. Half of the word targets are preceded by a related word, half by an unrelated word. Primes and targets are presented with a long stimulus-onset-asynchrony (SOA) of 1400 msec and with a short SOA of 300 msec. Normal priming effects are observed in Broca's aphasics for both SOAs. This result is discussed in the context of the claim that Broca's aphasics suffer from an impairment in the automatic access of lexical-semantic information. It is argued that none of the current priming studies provides evidence supporting this claim, since with short SOAs priming effects have been reliably obtained in Broca's aphasics. The results are more compatible with the claim that in many Broca's aphasics the functional locus of their comprehension deficit is at the level of postlexical integration processes.

Adult↗
PubMedDate not supplied

Noncriterial recollection: familiarity as automatic, irrelevant recollection.

Recollection is sometimes automatic in that details of a prior encounter with an item come to mind although those details are irrelevant to a current task. For example, when asked about the size of the type in which an item was earlier presented, one might automatically recollect the location in which it was presented. We used the process dissociation procedure to show that such noncriterial recollection can function as familiarity--its effects were independent of intended recollection.

Adult↗
PubMed1975

A syndrome of hypersomnia with automatic behavior.

Five male patients, complaining of daytime sleep attacks, and hav ing a history of automatic behavior, were recorded continously by polygraph for 108 h under two different protocols: (1ents were given specific tests to perform during Phase 1. Six normal males were run as controls during Phase . At the end of the recordings, patients had measurements of homovanillic acid (HVA) and 5 Hydroxy-indol Acetic Acid (5HIAA) in CSF before and after Probenecid testing. Patients appeared to present an abnormal sleep structure, with lack of Stage 3 and 4 NREM sleep, but had no significant increase in total sleep time during 24 h compared to normals. They also had repetitive very short periods of "micro-sleep" which account for their automatic behavior and were responsible for their great decrement in performance compared to normal controls. No CSF HVA and 5HIAA abnormality could be detected. This syndrome, which greatly impairs the social life and working ability of the patients, may be more related to an impairment of the "wakefulness" structures than to a dysfunction of the "sleep" structures.

Adult↗
PubMed2004

Strategic and automatic components in the processing of linguistic spatial relations.

The objective of the present study was to determine the extent to which strategies influence the representational format of a linguistic spatial relation. The propositional model assumes that a sentence describing a spatial relation is always represented as a set of propositions, whereas the strategic model claims that a spatial sentence can be represented either as a set of propositions or as a mental image, depending on the strategy (verbal or visual-spatial) an individual follows. Participants read a sentence (spatial or non-spatial) followed by a picture or sentence, which did or did not exemplify the information of the first sentence. In order to examine the involvement of strategic and automatic components the probability (20% or 80%) of the nature (sentence or picture) of the second stimulus was varied. Participants had slower verification RTs for unexpected stimuli than for expected stimuli, but this cost was significantly larger for an unexpected picture than an unexpected sentence. Furthermore, this asymmetric cost for the unexpected visual-spatial stimulus only occurred with spatial sentences and not with non-spatial sentences. Surprisingly, these data do not support a strictly propositional or a strategic model. Instead, we propose a third option: a dual representational model, in which people automatically represent the spatial sentence propositionally. In addition, depending on the context, a pictorial strategy is employed, which results in a supplementary visual-spatial representation.

Adult↗
PubMed2005

Controlled and automatic uses of memory in depressed patients: effect of retention interval lengths.

The present study examines controlled and automatic uses of memory in clinically depressed patients by applying the Process Dissociation Procedure developed by Jacoby (1991) to a stem completion memory task with short and long retention intervals. The results show that the contribution of controlled processes is lower in depressed patients than in controls, especially for the longest retention interval, whereas the contribution of automatic processes is equivalent in both groups and unaffected by the length of the retention interval. These findings are discussed in a cognitive control framework.

Adult↗
PubMed2006

The automaticity of emotional Stroop: a meta-analysis.

An automatic bias to threat is often invoked to account for colour-naming interference in emotional Stroop. Recent findings by McKenna and Sharma [(2004). Reversing the emotional Stroop effect reveals that it is not what it seems: The role of fast and slow components. Journal of Experimental Psychology: Learning, Memory, and Cognition, 30, 382-392], however, cast doubt on the fast and non-conscious nature of emotional Stroop. Interference by threat words only occurred with colour naming in the trial subsequent to the threat trial (i.e., a "slow" effect), but not immediately (i.e., a "fast" effect, as would be predicted by the bias hypothesis). In a meta-analysis of 70 published emotional Stroop studies the largest effects occurred when presentation of threat words was blocked, suggesting a strong contribution by slow interference. We did not find evidence; moreover, for interference in suboptimal (less conscious) presentation conditions and the only significant effects were observed in optimal (fully conscious) conditions with high-anxious non-clinical participants and patients. The emotional Stroop effect seems to rely more on a slow disengagement process than on a fast, automatic, bias.

Anxiety↗
PubMed2006

Unilateral hand automatisms in temporal lobe epilepsy.

OBJECTIVES: To analyse the lateralising value of unilateral manual automatism (UMA), its relation to contralateral dystonia and the hand by which the UMA was performed. METHODS: In this retrospective study, we reviewed video recordings of 141 patients (mean age 34.1+/-10) who had consecutively undergone presurgical evaluations with ictal video-EEG recordings and high-resolution MRI, had had epilepsy surgery due to intractable medial temporal lobe epilepsy with complex partial seizures due to unilateral medial temporal lobe lesions. The video recordings were prospectively reviewed by one of the authors blinded to patient's clinical data except the diagnosis of medial temporal lobe epilepsy. Altogether 310 archived seizures were analysed. RESULTS: Hand automatisms occurred in 86.5% of patients. UMA occurred in 53% of patients. If UMA was accompanied by contralateral hand dystonia, it had a high lateralising value to the ipsilateral epileptic focus (EF), it was ipsilateral in 85% of patients. Conversely, if UMA occurred without contralateral dystonia, it had only a limited lateralising value because it was ipsilateral to the EF in only 63% of patients. However, we found that left-sided UMA without dystonia had a high lateralising value to the left hemisphere (ipsilateral to the EF in 82%), while right-sided UMA without dystonia has practically no lateralising value. CONCLUSIONS: UMA with contralateral dystonia has a high lateralising value to the ipsilateral hemisphere. Left-sided UMA without contralateral dystonia has a lateralising value to the left hemisphere. Right-sided UMA without contralateral dystonia has no lateralising value.

Adolescent↗