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PubMed1992

Influence of time of 24-hour day on depth of processing in recall memory.

In this paper we report hourly variations in recall of words in a short-term memory task. Tests were carried out at 18.00, 22.00, 02.00 and 06.00 hours. The words to be memorized were preceded by a question designed to shape the type of encoding adopted by the subjects. The question concerned semantic, typographic or structural characteristics of the word. After presentation of all the words, the subjects were tested in free recall. Time of day had no effect on overall recall scores. Nevertheless, we observed a phase difference in the recall of items processed at superficial or deep levels. Items encoded by typographical attributes were more readily recalled at 02.00 than at 18.00, whereas semantically encoded words were less well recalled at night than during the day. There was also an interaction between the serial position of the items and time of day. At 22.00 and 02.00, subjects recalled words from the end of the list better. The results are discussed in terms of resource allocation models.

Adult↗

PubMedDate not supplied

Managing away bad habits.

We've all worked with highly competent people who are held back by a seemingly fatal personality flaw. One person takes on too much work; another sees the downside in every proposed change; a third pushes people out of the way. At best, people with these "bad habits" create their own glass ceilings, which limit their success and their contributions to the company. At worst, they destroy their own careers. Although the psychological flaws of such individuals run deep, their managers are not helpless. In this article, James Waldroop and Timothy Butler--both psychologists--examine the root causes of these flaws and suggest concrete tactics they have used to help people recognize and correct the following six behavior patterns: The hero, who always pushes himself--and subordinates--too hard to do too much for too long. The meritocrat, who believes that the best ideas can and will be determined objectively and ignores the politics inherent in most situations. The bulldozer, who runs roughshod over others in a quest for power. The pessimist, who always worries about what could go wrong. The rebel, who automatically fights against authority and convention. And the home run hitter, who tries to do too much too soon--he swings for the fences before he's learned to hit singles. Helping people break through their self-created glass ceilings is the ultimate win-win scenario: both the individual and the organization are rewarded. Using the tactics introduced in this article, managers can help their brilliantly flawed performers become spectacular achievers.

Career Mobility↗

PubMed1998

Neurological function after deep hypothermic circulatory arrest in the rat.

BACKGROUND: Integrated neurological function, behavior, and somatic recovery were studied in 35 rats undergoing 5 to 80 minutes of hypothermic circulatory arrest (HCA). METHODS AND RESULTS: A closed extracorporeal circulation system (ECC) consisting of a miniature oxygenator and heat exchanger, primed with 6 mL of asanguinous solution, was connected to a closed-chest rat with cannulae in the right atrium for venous drainage (ID = 1.7 mm) and in the ascending aorta for arterial return (ID = 1.0 mm). The rat was surface- and core-cooled until rectal temperature reached 18 degrees C, when ECC was stopped and cardioplegic solution delivered. After 5, 10, 20, 40 (each n = 5), and 80 minutes (n = 15) of HCA, the rat was reperfused, weaned from ECC, and followed with behavioral scoring, passive avoidance tasks, and cardiopulmonary exercise testing until euthanized for morphological study. Every rat resumed weight gain in the first week after HCA and regained preoperative exercise capacity by the fourth week. Only rats undergoing 80 minutes of HCA showed behavioral abnormalities such as stereotypy and incomplete righting reflex, which eventually disappeared in the fourth week. Learning ability was preserved in all except for rats after 80 min of HCA, who failed to acquire new memory to avoid electric stimuli (n = 10) up to 3 months after HCA, when pyramidal cells were partly replaced by astroglia in the cerebral cortex and CA1 sector of hippocampus. Nonetheless, old memory established before HCA was preserved even after 80 minutes of HCA and allowed rats (n = 5) to avoid electric stimuli. CONCLUSIONS: Homogeneity of animals, miniature ECC system, and an established testing system allowed evaluation of rats after HCA, which disclosed learning disability (functional disorder) and pyramidal cell loss (organic defect) after 80 minutes of HCA despite recovery of somatic function, behavior, and growth.

Animals↗

PubMed2006

Beyond 'faith-based medicine' and EBM.

RATIONALE, AIMS AND OBJECTIVES: Longstanding debate on evidence-based medicine (EBM) may have reached a critical saturation point. I briefly report on systematic reviews on the recurring themes in the critical literature. In this context, some criticisms to EBM are substantial and enduring, although convincing arguments to contrast unresolved issues have yet to be produced. Nonetheless, few changes have been adopted and conservative attitudes persist in EBM. Despite its 'success', implementation in practice has been inexorably overshadowed leading to paradoxical shortcomings. This controversial scenario offers a formidable occasion to gain needed insight. The aim of this paper is to attempt a comprehensive analysis by reframing a number of key concerns, while furnishing pragmatic, interdisciplinary solutions for these deep-rooted dilemmas. In the interests of all stakeholders, I seek to promote a concerted effort to resolve conflict and build consensus. METHODS: This paper explores a strategically unifying vision of primary care, based on current understanding of practice patterns, having a research-friendly 'common ground' where practitioners' information needs may be met. In addition, an analysis of existing problems identifies underlying 'root causes'. Moreover, I expediently reframe crucial matters by focusing on EBM, more than as a paradigm, as an organisation, hence amenable to a variety of cross-disciplinary analyses and solutions. Finally, recent state-of-the-art reviews on implementation and dissemination research are cited for the pertinent implications for study design and practice. RESULTS: Present policies and influential testimonials on behalf of EBM encounter the pitfalls of hindering learning and progress through defensive attitudes and mechanisms. Current study designs and evaluation criteria must strive to adapt to real-world settings, rather than vice versa. CONCLUSIONS: The arguments exposed herein alter the terms of the debate on EBM and may outline a basis for initiatives with conflict-resolution and consensus-building scopes.

Consensus↗

PubMed1996

Environmental factors and nutritional status of rural children.

The nutritional status of school-aged children is a growing concern of health care professionals today. In collaboration with a Kellogg Project in the deep south, students from a large university school of nursing participated in a project to improve the nutritional status of rural school-aged children. The project goals focused on educating thd children about the U.S. Department of Agriculture (USDA) Food Guide Pyramid, reading nutritional labels and recognizing foods with high fat content, and the importance of exercise along with diet. The nursing students created a nutritional assessment tool to use with each child to determine their educational needs. The project involved lecture, interactive class discussion, and hands-on activities. Information from the assessment tool revealed that fast food and foods high in fat were the most popular with the children. After project completion, the posttest revealed an increase in cognitive knowledge of nutrition among all the children. In addition to this positive learning experience for the children, improving the health status of children in the community was an excellent educational opportunity for the nursing students.

Child↗

PubMed2002

[Macular translocation with 360 degree retinotomy in the treatment if exudative macular degeneration. Functional and angiographic results].

BACKGROUND: During surgical extraction of choroidal neovascular membranes (CNV) in age-related macular degeneration (AMD), the defective foveal retinal pigment epithelium (RPE) is removed. Subsequent translocation of the foveal neural retina to adjacent healthy RPE should result in stabilization and possibly improvement of visual acuity. METHODS: A prospective case series was carried out using controlled surgery and examination protocols with examinations made at fixed intervals. The surgical procedures combine counterrotation of the globe, phacoemulsification and implantation of a posterior chamber lens, complete vitrectomy, induction of a total retinal detachment, 360 degrees anterior retinotomy, removal of the subfoveal neovascular complex, foveal translocation outside the RPE defect, reattachment of the retina using F6H8, peripheral laser retinopexy and temporary silicone oil tamponade. PATIENTS: Macular translocation surgery was performed on 100 patients between December 1997 and December 1999. All patients had experienced recent visual loss due to exudative AMD and of these, 26 patients had major macular subretinal hemorrhage, 39 patients had occult and 25 patients classic subfoveal choroidal neovascularization. The preoperative findings in the remaining patients included tears in the pigment epithelium (n = 4), polypoidal choroidal vasculopathy (n = 1), recurrent subfoveal CNV following laser therapy (n = 2) and deep retinal vascular anomalous complexes (n = 3). RESULTS: A total of 97 patients completed the 12-month examination. Visual acuity increased by 15 or more ETDRS chart letters in 24 patients, remained stable in 42 patients and deteriorated by 15 or more EDTRS chart letters in 34 patients 12 months postoperatively. The silicone oil tamponade was removed in 97 patients, in 10 patients, silicone oil had to be reinjected because of severe complications. A secondary procedure was necessary in 25 patients, primary PVR was observed in 9 eyes, secondary PVR developed in 10 eyes, a macular pucker in 5 eyes and a macular hole in 1 patient. Other postoperative complications included persistent hypotonia, macular edema, IOL dislocation, keratopathy and recurrent CNV (n = 3). CONCLUSIONS: Macular translocation is a technically demanding operation, which requires a considerable learning curve. Although the procedure has a high rate of surgical and postoperative complications, the functional and anatomical results appear to be promising for selected patients with subfoveal CNV secondary to AMD.

Aged↗

PubMed1984

Memory impairment in multiple sclerosis.

The memory performance of 22 Multiple Sclerosis (MS) subjects and their matched controls was compared on three tasks: a perceptual memory test, a picture recognition test and a verbal recognition test. Results showed that perceptual memory does not suffer as a consequence of MS. Moreover, MS subjects are as sensitive as controls to deep semantic encoding of individual items in a picture recognition task. However, for a verbal recognition task, where a semantic encoding strategy was optional, MS subjects were less likely to report use of a strategy. Those MS subjects who did use a strategy, did more poorly on memory for verbal information than controls. The results suggest a specific inter-item semantic encoding problem in MS.

Adult↗

PubMedDate not supplied

The motor core of speech: a comparison of serial organization patterns in infants and languages.

Comparison of serial organization of infant babbling and early speech with that of 10 languages reveals four movement-related design features reflecting a deep evolutionary heritage: (1) the cyclical consonant-vowel alternation underlying the syllable, a "Frame" for speech consisting of mandibular oscillation, possibly evolving from ingestive cyclicities (e.g., chewing) via visuofacial communicative cyclicities (e.g., lipsmacks); (2) three intracyclical consonant-vowel co-occurrence preferences reflecting basic biomechanical constraints-coronal consonants-front vowels, dorsal consonants-back vowels, and labial consonants-central vowels; (3) a developmental progression from above-chance to below-chance levels of intercyclical consonant repetition; (4) an ease-related labial consonant-vowel-coronal consonant sequence preference for word initiation. These design features presumably result from self-organizational responses to selection pressures, primarily determined by motor factors. No explanation for these design features is available from Universal Grammar, and, except for feature 3, perceptual-motor learning seems to have only a limited causal role in acquisition of any design feature.

Child↗

PubMed2004

Reoperations after 3200 revision TKAs: rates, etiology, and lessons learned.

The purpose of this study was to evaluate the prevalence, etiology, and evolution with time of reoperations done after index revision total knee arthroplasties. After exclusion criteria were met, 1814 index knee revisions in 1627 patients were included in the final cohort with more than 50% of the revisions done for loosening and extensor mechanism problems and more than 80% of the revisions involving the femoral, tibial, or both components. Three hundred seventy-three knees subsequently have been reoperated on one or more times. The average time from index revision total knee arthroplasty to the first reoperation was 3.5 years (range, 1 day-19 years). Of the 1814 index revision total knee arthroplasties, 373 (20%) had 593 reoperations in 336 patients. The cumulative risks of first reoperation at 5, 10, and 15 years were 16.1% (95% CI, 14.2, 17.9), 26% (95% CI, 23.4, 28.6), and 31.4% (95% CI, 30.2, 39), respectively. There was no difference in risk to first reoperation when comparing the decades in which the index revisions were done (1970-1980, 1981-1990, and 1991-2000). There was a trend toward a higher cumulative risk of first time reoperations for deep infection, loosening, and instability in the last decade, but with the numbers available this was not statistically significant. The prevalence of reoperations in this large series of index revision total knee arthroplasties done for aseptic reasons was surprisingly high. Despite substantial improvements during the past 3 decades in component design, surgical technique, and prevention of infection, patients who have a revision total knee arthroplasty are at substantial risk of having one or more subsequent problems that result in a reoperation.

Arthroplasty, Replacement, Knee↗

PubMed1992

[Snow-white in danger. Women, socialization and health. Some messages, by means of allegory].

This is the modern-day allegory of Snow White, the most beautiful woman in the kingdom. Because of her beauty she is banished from the castle. The seven dwarfs who befriend her welcome her into their cottage. Little by little, they begin to impose their demands on her. They try to coerce her into submitting to life's little demands in order to attain beauty, health and happiness. Diet categorizes the foods filled with nasty calories that Snow White must learn to do without. Fitness outlines her spare time exercise regimen to keep her slim and trim. Mr. Clean provides her with specific household cleaning tips. Job tips advise her how to get a job outside the home to maintain her financial autonomy. Pills provide her with a way to assure a smooth transition between work and the household chores. Oh! And we almost forgot Baby. Who will care for Baby? Snow White of course--since she is the only woman in the house. Finally, to assure perfect co-ordination of all these tasks, Excel sends her off to take a time management course. Snow white responds enthusiastically to all the expectations. As anticipated, she loses weight. She then becomes exhausted and collapses and is transformed into Burnt-Out Beauty. She remains in a deep sleep for 100 days and nights. The dwarfs place her in a glass box in a forest clearing where she is discovered by Prince Conscience. He opens the glass box, kisses her lightly on the forehead, and immediately disappears. Snow White awakens and remembers the events preceding her deep sleep.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

PubMed1985

The corticomotoneuronal component of the pyramidal tract: corticomotoneuronal connections and functions in primates.

Corticomotoneuronal fibers make up a functional component of the pyramidal tract-corticospinal system which is characteristic of primates. The corticomotoneuronal fibers include large, rapidly conducting axons. They arise from somatotopically arranged areas of precentral cortex and the largest concentration of pyramidal cells of origin in the deep part of lamina V is in area 4. Their influence is exerted contralaterally on the spinal cord, where monosynaptic excitation of spinal motoneurons occurs. Motoneurons innervating distally acting muscles are preferentially excited and marked convergence of corticomotoneuronal influences occurs on these. The excitatory post-synaptic potentials in these motoneurons are characterized by the property of temporal facilitation. Intraspinal divergence of the terminal arborizations of individual corticomotoneuronal fibers could permit the engagement of large populations of motoneurons and also the activation of excitatory and inhibitory interneurons and propriospinal neurons for that region of the spinal cord. Corticomotoneuronal synapses may be located more distally on the dendrites of motoneurons than are the monosynaptic connections from group Ia afferents. The corticomotoneuronal excitation has been demonstrated to be effective in natural functional states when the conscious animal is performing learned movement tasks. Abolition of corticomotoneuronal influences causes a permanent deficit in the fractionation of use of distal muscles and an inability to carry out independent movements of the fingers.

Animals↗

PubMedDate not supplied

Air-guided manual deep lamellar keratoplasty.

PURPOSE: To evaluate the efficacy of a new modified technique of deep lamellar keratoplasty (DLK). METHODS: Nine eyes of eight patients with keratoconus of moderate degree were included. All patients underwent DLK with manual dissection from a limbal side port after an air bubble injection in the anterior chamber. The patients underwent a complete ophthalmologic examination 6 months after the suture removal, evaluating best-corrected visual acuity, corneal thickness, endothelial cell count, and topographic astigmatism. RESULTS: One case (11.1%) was converted to penetrating keratoplasty because of microperforation. In the eight successful cases, 7 eyes (77.8%) achieved 20/30 or better visual acuity 6 months after suture removal. Mean postoperative pachymetry was 604.76 microm (SD 46.76). Specular microscopy 6 months after suture removal revealed average endothelial cell count of 2273/mm2 (SD 229). CONCLUSIONS: This modified DLK technique is a safe and effective procedure and could facilitate, after a short learning curve, this kind of surgery with a low risk of conversion to penetrating keratoplasty.

Adult↗

PubMed1983

Religious and mystical experiences as artifacts of temporal lobe function: a general hypothesis.

Mystical and religious experiences are hypothesized to be evoked by transient, electrical microseizures within deep structures of the temporal lobe. Although experiential details are affected by context and reinforcement history, basic themes reflect the inclusion of different amygdaloid-hippocampal structures and adjacent cortices. Whereas the unusual electrical coherence allows access to infantile memories of parents, a source of good expectations, specific stimulation evokes out-of-body experiences, space-time distortions, intense meaningfulness, and dreamy scenes. The species-specific similarities in temporal lobe properties enhance the homogeneity of cross-cultural experiences. They exist along a continuum that ranges from "early morning highs" to recurrent bouts of conversion and dominating religiosity. Predisposing factors include any biochemical or genetic factors that produce temporal lobe lability. A variety of precipitating stimuli provoke these experiences, but personal (life) crises and death bed conditions are optimal. These temporal lobe microseizures can be learned as responses to existential trauma because stimulation is of powerful intrinsic reward regions and reduction of death anxiety occurs. The implications of these transients as potent modifiers of human behavior are considered.

Culture↗

PubMed1993

Training immigrant doctors: issues and responses.

An unprecedented wave of immigration of doctors to Israel, mainly from the former Soviet Union, posed for Israeli health leaders the problem of bringing them to a common and accepted Western level of performance. Stemming from the deep commitment which Israel has towards the immigrants, the state offers them a training opportunity to enhance their chances of being licensed and finding jobs in their profession. A 6-month programme was launched by Ben-Gurion University, later adopted by other medical schools and supported by the Government of Israel. The programme was designed to provide effective responses to the specific problems of the immigrant population, which are: lack of knowledge of local language, both everyday and professional; overspecialization in too narrow specialties; possession of clinical specialties which do not exist in the new country; insufficient updating in medical sciences and technology; unawareness of economic implications of health care; difficulty in originating new solutions to clinical problems, and lack of skill in answering objective test items. The programme is characterized by a protective environment, problem-oriented learning, small-group activities and emphasis on learning languages. The clinical problems are designed to emphasize the general practitioner's point of view of both common and emergency situations. The programme has achieved its goals, as judged by the success rate of its graduates in the National Licensing Examination as compared with the success of immigrant doctors who chose not to participate in the training.(ABSTRACT TRUNCATED AT 250 WORDS)

Education, Medical, Graduate↗

PubMed2002

Suppression of absence seizures by electrical and pharmacological activation of the caudal superior colliculus in a genetic model of absence epilepsy in the rat.

Activation of the superior colliculus has been shown to reproduce the antiepileptic effect of the inhibition of the substantia nigra reticulata. A circuit involving neurons of the caudal deep layers of the superior colliculus has been suggested to control brain stem convulsive seizures. The present study was designed to examine whether a similar circuit is also involved in the control of absence seizures. For this, activation of either the rostral or caudal parts of the deep and intermediate layers of the superior colliculus was applied in a genetic model of absence seizures in the rat (GAERS). Single-shock (5 s) electrical stimulation of the rostral and caudal superior colliculus interrupted ongoing spike-and-wave discharges at an intensity (antiepileptic threshold) significantly lower than the intensity inducing behavioral effects. At this intensity, no interruption of licking behavior was observed in water-deprived rats. Repeated stimulations (5 s on/5 s off) at the antiepileptic threshold reduced absence seizures only during the first 10 min. Bilateral microinjection of a GABA antagonist (picrotoxin, 33 pmol/side) significantly suppressed spike-and-wave discharges when applied in the caudal aspect of the superior colliculus. This antiepileptic effect appears dissociated from an anxiogenic effect, as tested in an elevated plus maze test. Finally, bilateral injection of picrotoxin (33 pmol/side) appeared more effective in the superficial and intermediate layers of the caudal superior colliculus, whereas such injections had only weak effects on absence seizures when applied in the deep layers. These results suggest that a specific population of neurons located in the intermediate and superficial layers of the caudal superior colliculus is involved in the inhibitory control of absence seizures. It may constitute an important relay for the control of absence seizures by the basal ganglia via the substantia nigra reticulata.

Animals↗

PubMed1977

Models of membranes of cerebral cells as substrates for information storage.

The past decade has seen a growing understanding of functional capacities and structural organization of cell membranes. Studies in immunology, endocrinology and neurobiology have led to some unifying concepts about processes of transduction at the membrane surface, and the coupling of surface events to the interior of the cell. My interest in these problems has been directed in no small measure by interactions with Lars Onsager. His kindly tutelage and rigorous criticism have been a source of endless encouragement to those who sought the full measure of his wisdom in the difficult area of the energetics of membrane excitation. Onsager's unflagging interest in mechanisms of ion transportation led him to earnest consideration of a variety of non-classical models of conduction in proteins, always tempered by his deep insight essential aspects of physical chemistry. My discussions with him at the MIT Neuroscience Research Program were a regular stimulus to the experiments which our groups have undertaken in search of answers to questions raised by the models presented here. Above all, Lars Onsager was a kindly, gentle man. In this personal example, he will be as sadly missed as for his broad and imaginative approach to critical questions in the physical and biological sciences.

Animals↗

PubMed2026

A systematic approach to standardizing the visual appearance of endometriotic lesions for artificial intelligence recognition.

INTRODUCTION: Numerous studies have shown that the diagnostic performance and reproducibility of visual recognition of endometriosis during laparoscopy are poor. The use of artificial intelligence (AI) seems relevant for exhaustive lesion recognition. Standardization of the visual classification of lesions, in the form of an ontology, is an essential prerequisite to enable medical experts to annotate surgical data consistently and subsequently allow engineers to train and build an artificial intelligence tool for endometriosis recognition. MATERIAL AND METHODS: A systematic search was conducted in the MEDLINE (via PubMed), EMBASE, and the Cochrane Library databases up to May 2022, aiming to identify studies describing the laparoscopic visual appearance of superficial endometriosis, endometriomas, and deep infiltrating endometriosis. The accumulated data in the literature concerning the visual appearance of the different forms of endometriosis were used to create an ontology that could be used for artificial intelligence applications. RESULTS: Out of 932 articles screened, 35 studies were selected based on the inclusion criteria of human subjects with histologically confirmed endometriosis lesions visualized via laparoscopy. The selected studies were reviewed to develop a visual ontology of endometriosis lesions observed via laparoscopy. The lesions were categorized into 4 classes and further subdivided into 11 subclasses: superficial (black, red, white, or subtle), adhesions (dense or filmy), deep (obliteration, retraction, or deformation), and ovarian (endometrioma or chocolate fluid). The positive predictive value (PPV) varied across lesion types: black lesions (PPV 47%-97%), red lesions (PPV 33%-100%), white lesions (PPV 20%-81%), and ovarian endometriosis (PPV 42%-98%). Nonspecific lesions such as adhesions (PPV 16%-50%) and subtle superficial lesions (PPV 0%-67%) presented lower PPVs. Deep endometriosis lesions, often buried within organs, required indirect signs (obliteration, retraction, deformation) for identification. CONCLUSIONS: The visual ontology proposed in this systematic search could facilitate the detection and classification of endometriosis lesions using artificial intelligence. This study highlights the challenges of reaching a consensus on lesion recognition and classification in AI projects due to the diverse visual presentations of endometriosis.

Humans↗

PubMed1985

Event related aspects of somatosensory and auditory evoked potentials: noise or signals?

The so-called Vertex Potential (VP) of human scalp-conducted and event related brain potential (ERBP), which occur as a slow and often large, biphasic sinusoid within the 100-400 msec time segment after transient stimulation in the three main sensory modalities, are the longest researched of all human evoked potential (EP) phenomena. Its variable amplitude has been directly correlated, in experiments expressly tailored for the purpose, with input/output variables such as the rate of acceleration of given stimulus parameters from a state of relative rest (RM function), interstimulus interval (ISI), stimulus intensity, skin potential and resistance changes (SPR and SRR), the peripheral electroneurogram (ENG), and experimentally isolated C-fiber afference; and with neuropsychological variables such as attention or vigilance, visual acuity, response time, subjective stimulus probability or expectancy, acute pain of both fast and slow kinds, intelligence quotient (IQ), and psychometric personality scores (e.g., extraversion versus introversion and neuroticism versus normality). Unfortunately, the cerebral, neural origins of the VP, if any, are unknown; it is reported as usually absent from cortex-surface EP in those primates and mammals hitherto studied, and also from human extracranial event related magnetic fields of the brain (ERMFb) insofar as these reveal only superficial tangential sources; but a possible analog has been recorded from deep subcortical electrodes during human neurosurgery. In view of the increasing published range and quantity of direct correlates of VP amplitude, and of the scarcity of data about its neuroanatomy and neurophysiology, it seemed a good idea to do some rudimentary signal analysis. Preliminary results from five subjects confirm earlier data: The VP of somatosensory (SEP) and auditory (AEP) evoked potentials, as obtained by scalp-conductance and either averaged or single-epoch, can be resolved into inconsistently stimulus synchronized frequency components which are also present as relatively unsynchronized waves in the theta and alpha bands (approx. 2-13 Hz) of the unstimulated or near-threshold-stimulated electroencephalogram (EEG). In averages of numerous single trials (20 less than N less than 102), initiated at interstimulus intervals longer than 2.5 sec and deliberately sequenced so that the initiator could learn to estimate the timing of stimulus onsets, the phase coherence of the power-dominant alpha and theta waves within the 100-400 msec time segment of ERBP is obvious when the stimulus is an intense transient and psychologically not "habituated".(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗