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PubMed2006

How automatic are audiovisual links in exogenous spatial attention?

Three experiments on healthy humans investigated the degree of automaticity of crossmodal spatial attention shifts by assessing the intentionality criterion. We used the orthogonal cuing paradigm in which a lateralized cue, either visual or auditory was followed by a unimodal or crossmodal target that occurred at the same or opposite side. In all experiments, the cue was always uninformative as to target location. In Experiment 1, where both side and modality of targets were unpredictable, we found faster discriminations for visual targets following uninformative auditory cues on the same side. This result was replicated in Experiment 2, where target side was blocked and participants could orient attention in advance toward the appropriate side, and in Experiment 3, where they were additionally informed about target modality. Our results suggest that this sort of crossmodal orienting is automatic because it occurred even when participants were provided with detailed information about the target to prevent uninformative auditory cues from orienting attention. This is consistent with the notion that peripheral auditory stimuli are very powerful in capturing visual attention.

Adolescent↗

PubMed2005

Transdermal nicotine administration enhances automatic auditory processing reflected by mismatch negativity.

Mismatch negativity (MMN) is a component of event-related potentials (ERPs) with a wide-ranging applicability to the investigation of neuronal substrates of information processing in normal and psychopathological states. Nicotine has been shown to be implicated in the pathophysiology of psychiatric disorders as schizophrenia or Alzheimer's disease, and has also been proposed as a self-administered drug in schizophrenia. The goal of the present study is to elucidate the effect of nicotine on the auditory automatic processing reflected by MMN. Nicotine was administered transdermally under controlled dosage. Ten healthy volunteers attended the laboratory for one baseline session and two test sessions. The test sessions involved administration of a placebo patch and a nicotine skin patch, which were counter-balanced. The ERPs were recorded passively during an auditory oddball paradigm. Nicotine administration shortened the MMN latencies, and these effects were independent of the earlier ERP components, N100 and P200. In conclusion, nicotine enhances preattentive and automatic processing such as MMN system and these effects appear to be quite specific and independent of earlier cognitive stages than preattentive mismatch processing. The shortened MMN latency may be interpreted as a reduction of the amount of time required to complete a neuronal mismatch process through the ascending auditory pathway.

Acoustic Stimulation↗

PubMed2005

Automatic and effortful emotional information processing regulates different aspects of the stress response.

There is increasing evidence that stress and self-regulation are important factors in the development and treatment of psychopathology. A key issue is to determine how cognitive-emotional systems modulate the stress response. We sought to determine whether effortful and automatic processing were differentially associated with subsequent mood and cortisol levels during a stressful challenge. We examined this question by having clinically anxious, depressed, and control participants perform a modified spatial cueing task with supraliminal and masked pictorial stimuli during a stressful challenge and control condition. The stressful challenge, relative to the control condition, lowered mood, but did not influence cortisol levels. In the full sample, disengagement from supraliminal dysphoric pictures was associated with subsequent mood ratings, whereas disengagement from masked pictures depicting threat was associated with subsequent cortisol levels. Effortful and automatic processing appears to regulate different aspects of the stress response.

Adaptation, Psychological↗

PubMed2006

Assessment of 18F PET signals for automatic target volume definition in radiotherapy treatment planning.

INTRODUCTION: Positron emission tomography (PET) alone or in combination with computer tomography (PET/CT) is increasingly used in target volume assessment. A standardized way of converting PET signals into target volumes is not available at present. MATERIALS AND METHODS: Assuming a uniform signal emission from a tumour and surrounding normal tissues, a model-based method was developed to determine a relative threshold level (Th(rel)) for gross tumour volume delineation. Two phantoms consisting of cylindrical and spherical sources of diameter ranging from 4.5 to 43 mm in a tank and (18)F activities ranging from 0.001 to 0.15 MBq/ml for tank and sources, respectively, were used for PET/CT imaging. A Th(rel) was calculated that best corresponded to the physical diameter of the cylindrical sources. Software (SW) was generated to automatically delineate volumes based on this threshold. The SW was validated for in vitro and in vivo PET signals. RESULTS: The Th(rel) best representing the source diameter was 41+/-2.5% (95% confidence level) of the background-subtracted signal. The mean deviation for sources of diameter > or =12.5 mm was < or =1.5 mm. The Th(rel) was constant for diameters > or =12.5 mm. For source diameters <12.5 mm, the 41% level over-estimated the real source diameter by a factor depending on the diameter. In an in vitro set-up the SW was capable of segmenting solitary PET volumes to within 1.4 mm (1SD). For non-homogeneous signals in a clinical set-up minimal manual intervention is presently required to separate target from non-target signals. The SW may slightly underestimate target volumes when compared with CT-based volumes, but works well as a first approximation. The volume can be manually adapted to give the ultimate target volume. CONCLUSIONS: SW-based automatic delineation of the volume of (18)F activity is feasible and highly reproducible. Volumes can be subsequently modified by the clinician if necessary. This approach will increase the efficiency of the planning process.

Automation↗

PubMed2004

In hospital cardiac arrest: a role for automatic defibrillation.

INTRODUCTION: Sudden cardiac death (SCD) survival decreases by 10% for each minute of delay in defibrillation, however, survival rates of 98% can be achieved when defibrillation is accomplished within 30s of collapse. Recently, a fully automated external cardioverter-defibrillator (AECD) was approved by the FDA for in-hospital use. The AECD can be programmed to automatically defibrillate when a life threatening ventricular arrhythmia occurs. The purpose of this study was to assess the potential impact of in-hospital AECDs on the critical time to defibrillation in monitored hospital units. METHODS: Mock emergency (n = 18) were conducted using simulated ventricular fibrillation in various monitored units. Observers were stationed to record the time staff responded to the arrhythmia, and the time to shock. These times were compared to an AECD protocol that defibrillates automatically in an average of 38.3 s from onset of arrhythmia (n = 18). RESULTS: Staff versus AECD response time to arrhythmia (s) was 76.3 +/- 113.7 (CI 19.8-132.8) versus 7.6 +/- 0.6 (CI 7.3-7.9). Staff versus AECD time to shock was 169.2 +/- 103.1 (CI 117.9-220.4) versus 38.3 +/- 0.7 (CI 37.9-38.6). P-values are <0.0001 for differences between the groups. CONCLUSION: The use of AECDs on monitored units would significantly reduce the critical time to defibrillation in patients with SCA. We anticipate this would translate to improved survival rates, and better neurologic outcomes.

Electric Countershock↗

PubMedDate not supplied

Assessing the effects of automatically delivered stimulation on the use of simple exercise tools by students with multiple disabilities.

We assessed the effects of automatically delivered stimulation on the activity level and mood (indices of happiness) of three students with multiple disabilities during their use of a stepper and a stationary bicycle. The stimulation involved a pool of favorite stimulus events that were delivered automatically, through an electronic control system, while the students were active in using the aforementioned exercise tools. Data showed that stimulation had an overall positive impact, but this was not evident on both measures (i.e., level of activity and indices of happiness) or with both exercise tools across students. These findings are discussed in relation to the outcome of an earlier study in the area by the same authors and in terms of practical implications for daily contexts.

Adult↗

PubMed2006

Automatic measurement of the nonlinearity parameter B/A in liquid media.

Using a 19-MHz focused Gaussian beam generated by a LiNbO(3) plate with an inverted polarization layer coupled to an acoustic lens, a method to automatically measure the nonlinearity parameter B/A in liquid media is presented. A liquid sample is poured into a cylindrical cell set with a glass tube on the lens surface. The focusing source emits burst waves. A tungsten rod immersed in the sample so that the top surface is normal to the beam axis behaves as a perfect reflector. The position of the reflector to maximize the amplitude receiving the returned wave determines the sound speed c of the sample. The amplitude measurement for the waves returned from the lens-sample interface and the reflector surface leads to the determination of the density rho and attenuation coefficient alpha, respectively. Then the B/A is finally derived by summarizing the measured result of the 38-MHz second harmonic amplitude contained in the sound returned back from the reflector, together with rho, c and alpha. All these are automatically processed in a short time less than 2 min with the performance of computer controlled instruments.

Algorithms↗

PubMed2003

An automatic approach for morphological analysis and malignancy evaluation of ovarian masses using B-scans.

Ovarian masses are a common phenomenon among women of all ages. The importance of prompt diagnosis of ovarian malignancies is obvious, due to the high mortality rate and the difficulty to detect a tumor in its early stages. In this work, an automatic technique for quantitative analysis and malignancy detection of ovarian masses using B-scan ultrasound (US) images is presented. The core of the technique is morphologic analysis of the ovarian mass. The method employed for this task is divided into two major stages: initial classification of the mass (into one of the three major tumor types: cyst, semisolid, solid), and detailed analysis of the mass. Malignancy evaluation is performed based on the collected data and the criteria provided by commonly used scoring systems. The results reflect adequate performance of the automatic method developed (referring to clinical requirements).

Algorithms↗

PubMedDate not supplied

[Comparison of the results obtained through manual and automatic phonetogram].

INTRODUCTION: The phonetogram (F) is the graphic representation of a person phonatory potential. The F carried out with a sonometer and a frequency analyser is what is called "manual phonetogram" (MPh), and the one obtained by means of a computer is called the "automatic phonetogram" (APh). MATERIAL AND METHODS: We have carried out in 12 lyrical singers a standard MPh and an APh with the program Dr. Speech Science 3.0. RESULTS: It was showed a significant difference with a p < 0.0005 in 14 of the 15 measures compared, and a p < 0.05 for the other one, being in general the results of the automatic test different from those of the manual in excess, with a correlation between the results obtained through both methods. CONCLUSIONS: The APh obtained with the program Dr. Speech Science 3.0 is a faster and easier way to obtain the phonetogram than the one used to obtain the MPh, showing however big differences in excess compared with the ones of the MPh in all the usual phonetometric parameters.

Adult↗

PubMed2005

[Occupational allergic contact dermatitis from color developers used in automatic developing].

The color developers CD2, CD3 and CD4 and the black-and-white developer TSS are well known contact allergens that affect those who work in photographic processing. The frequency of occupational allergic contact dermatitis from color developers has decreased in recent years because of the fact that most photo developing takes place automatically, reducing exposure to different chemicals used in developing. We present a case of occupational allergic contact dermatitis in a non-atopic male who had worked for the last 5 years in a photography shop equipped with an automatic developing machine. The clinical morphology of the lesions was eczematous, and the patch tests showed contact sensitization to CD2, CD3, CD4 and TSS. The clinical symptoms cleared up when direct contact with the developing product containing CD3 and CD4 was avoided.

Adult↗

PubMed2003

Performance of an automatic external cardioverter-defibrillator algorithm in the discrimination of supraventricular from ventricular tachycardia.

An automatic external cardioverter-defibrillator (AECD) with a programmable supraventricular-ventricular tachycardia (VT) zone underwent evaluation of arrhythmia discrimination performance in the electrophysiologic laboratory during induced supraventricular tachycardia (SVT) and unipolar and bipolar atrial pacing. The AECD SVT zone was programmed so that the induced SVT rate would fall within this zone. Atrial pacing was also performed at a rate within this zone. The ability of the AECD to accurately discriminate between VT and SVT and to recommend shock delivery was assessed. A total of 98 patients underwent conventional diagnostic electrophysiologic studies (49 men, age 59 +/- 19 years) with a total of 55 inducible sustained SVTs. High right atrial pacing was performed in 56 patients in unipolar and in 82 patients in bipolar fashion. In response to induced sustained SVT, the AECD correctly classified 47 episodes as nonshockable, 4 incorrectly as shockable, and 4 episodes correctly as shockable with a resultant sensitivity of 100% and specificity of 92%. Bipolar high right atrial pacing was correctly identified as nonshockable in 75 episodes, incorrectly identified as shockable in 5 episodes, and correctly identified as shockable in 2 episodes with a resultant sensitivity of 100% and specificity of 94%. The Powerheart AECD accurately discriminates SVT from VT and is expected to correctly deliver automatic external shocks rapidly in the presence of spontaneous life-threatening tachycardia and appropriately withhold therapy during SVT.

Adult↗

PubMed1997

Accuracy of an automatic and patient-triggered long-term solid memory ambulatory cardiac event recorder.

This study evaluated the R-Test Evolution, a new type of cardiac event recorder bearing both patient-triggered and automatic capabilities. Its 7-day automatic arrhythmia analysis showed promising clinical advantages, especially when investigating patients with unexplained rare events such as syncope, feeling of weakness or faintness, palpitations, stroke, or in patients inconsistent in their use of patient-triggered recordings.

Arrhythmias, Cardiac↗

PubMed1998

Effect of dual-chamber pacing with automatic rate-drop sensing on recurrent neurally mediated syncope.

We tested the hypotheses that a dual-chamber pacemaker that paces when intrinsic rate drops abruptly would reduce the number of syncopal spells and improve the quality of life in patients with highly recurrent neurally mediated syncope. Twelve patients with highly frequent neurally mediated syncope and at least 1 syncopal spell after tilt testing received dual-chamber pacemakers with automatic rate-drop sensing. The pacemakers were implanted 17+/-26 months after tilt testing, and the patients then were followed for 12+/-2 months. We compared the time to the first recurrence of syncope, syncope frequency, and quality of life for the 2 periods between tilt testing and pacemaker implantation, and between implantation and last follow-up. Only 6 of 12 patients fainted after pacemaker insertion. The median time to syncope recurrence before and after pacing was 7 days and 5.3 months, respectively. The geometric mean frequency of faints before and after pacing was 5.0 spells/month (95% confidence interval 2.7 to 9.2) and 0.30 spells/month (95% confidence interval 0.2 to 0.4), p <0.001. After 6 months the mean perception of health on the 100-point EuroQol scale rose from 55 to 82 (p = 0.003), and the general health perception on the SF-36 scale rose from 51 to 72 (p = 0.005). Permanent dual-chamber pacing with automatic rate-drop sensing in patients with highly frequent syncope is associated with a marked reduction in the likelihood of syncope and a marked improvement in quality of life.

Adolescent↗

PubMed1989

Transdiaphragmatic implantation of the automatic implantable cardioverter defibrillator.

A new surgical approach for implantation of the automatic implantable cardioverter defibrillator without thoracotomy was used in 12 patients, aged 46 to 72 years. Preimplantation arrhythmia was ventricular tachycardia in 7 patients and ventricular fibrillation in 5 patients. The mean ejection fraction was 19%. Six patients were at high risk for general anesthesia for a variety of medical problems, and 2 patients had had a previous cardiac operation. Epidural anesthesia was used in 8 patients without intubation. The surgical approach used a longitudinal epigastric extraperitoneal incision with access to the heart through an incision made in the central tendon of the diaphragm. Two patches and two epicardial sensing leads were placed in all patients. All patients but one could be defibrillated with 20 J or less. There was no operative mortality and minimal morbidity. There were two late deaths due to heart failure. Thus, the transdiaphragmatic approach provides an excellent exposure for automatic implantable cardioverter defibrillator implantation, avoids general anesthesia and thoracotomy, and can be used after a previous cardiac operation.

Aged↗

PubMed1999

Cardiac pacing in premature infants and neonates: steroid eluting leads and automatic output adaptation.

BACKGROUND: Appropriate generator and lead selection as well as techniques of implantation are most important aspects of cardiac pacing in the extremely young patient. Here we report the clinical results using a new technique with automatic output adaptation based on evoked response in combination with steroid-eluting epicardial leads in small children. METHODS: One neonate and 2 premature infants underwent permanent pacemaker implantation because of congenital high-degree atrioventricular block or postoperative complete heart block, respectively. Steroid-eluting epicardial leads and a multiprogrammable pacemaker with automatic output adaptation were used. RESULTS: Intermuscular abdominal generator placement and epicardial suture-fixation of the bipolar lead through a subcostal approach was without complications. Serial follow-up examinations revealed safe and consistent pacemaker function up to 12 months after operation. CONCLUSIONS: The technique represents an excellent alternative for permanent cardiac pacing in extremely small patients. We believe that it provides an increase in functional lifetime of the devices and delays the need for battery replacement with its associated complications in this young patient population.

Algorithms↗

PubMed2000

Recent advances in the assessment of aberrant behavior maintained by automatic reinforcement in individuals with developmental disabilities.

Many aberrant behaviors exhibited by individuals with developmental disabilities are maintained by "automatic reinforcement". These behaviors are often difficult to treat, with the most effective behavioral interventions often resulting in only moderate success. However, a series of recent studies has advanced our ability to understand and treat these behaviors through the innovative use of behavioral assessment. We review the recent development of three categories of assessments: (a) nonhypothesis-based stimulus preference assessments, (b) hypothesis-based stimulus preference assessments, and (c) hypothesis-based assessments incorporating noncontingent reinforcement and sensory extinction procedures. We consider each category's contribution to both our ability to prescribe effective behavioral interventions and our ability to more fully understand the concept of automatic reinforcement.

Behavior Therapy↗

PubMed2000

Selection of an optimal combination of decision criteria for the internal quality control in an automatic analyzer.

After some years using an automatic analyser model Hitachi 705, we faced the task of selecting a reasonable combination of statistical procedures for internal quality control in order to use it in a computer program, by means of which, one could apply all the decision criteria in a rapid and automatic manner. As a result of the first 3 years of work, an algorithm was adopted that includes the multirule procedure originally proposed by Westgard, but with three main differences: (1) All the control rules are always applied; (2) the 4(1S) and 10x control rules are used as criteria for warning or caution but not for run rejection; and (3) the control limits are recalculated daily using all the accumulated control results (just the accepted values). The 2(2S), 4(1S) and 10x rules are applied first across materials (considering consecutive observations in different control materials), and then within materials (for consecutive observations on the same control material). The program not only has permitted us to improve our capacity for error detection, but it has also permitted the reduction of run rejections making an important decrease in costs possible and a significant improvement in quality.

Algorithms↗

PubMed2002

The effects of automatic artifact rejection on evoked potential recordings.

An analysis of the effects of automatic artifact rejection on the evoked potential recordings is made using both a theoretical analysis and computer simulations. It is demonstrated that when the noise at each measurement point is independently distributed with maximum probability near zero amplitude, the bias and changes in variance induced by the automatic artifact rejection are small unless more than 80% of traces are rejected. When high-amplitude noise transients occur, there can be significant bias in the evoked potential when the artifact rejection threshold is set near the amplitude of the noise transients. Even more substantial distortions in the evoked potential occur when the noise is not independently distributed at each measurement point. It is important to recognize the possibility of these effects during clinical evoked potential recording.

Artifacts↗