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PubMed1988

Serial changes in acute extradural hematoma size and associated changes in level of consciousness and intracranial pressure.

The authors report the cases of 37 patients encountered during the past 4 years who exhibited acute extradural hematoma but were initially treated conservatively because no or only small hematomas were observed on admission. The frequency of hematoma enlargement, hematoma size, and changes in the level of consciousness and intracranial pressure (ICP) were examined in these patients. The hematomas enlarged in 24 (64.9%) of the 37 patients, and attained a maximum thickness of 25 mm or greater in 19 patients (51.3%). The level of consciousness could be closely observed during enlargement of the hematomas in 13 patients: the level remained unchanged in eight, deteriorated in two, and improved in three, indicating relative stability in the state of consciousness despite the marked changes in hematoma size. The patients whose hematoma enlarged after the initial examination included three who underwent initial CT examination 5 hours after the injury. In five patients enlargement of extradural hematomas was observed unexpectedly during conservative treatment under ICP monitoring. The ICP also remained stable in three patients until the follow-up examination, but showed a rapid increase in two after a period of stability. However, there was no difference in the final size of the hematomas between the patients showing an increase in ICP and those who did not. These findings suggest that extradural hematomas enlarge progressively at rates varying with the condition of the source of hemorrhage. Moreover, a period of stability in the level of consciousness, such as the lucid interval seen in patients with extradural hematoma, is considered to be a period during which compensatory mechanisms can maintain the stability of the intracranial condition during progressive enlargement of the hematoma.

Adolescent↗
PubMed1991

Neural networks, brainwaves, and ionic structures: acupuncture vs. altered states of consciousness.

It is shown that neural networks with embedded "brainwaves" can cross the gap between the fast parallel unconscious mode of neuroscience and the slow serial conscious mode of psychology. The electromagnetic (EM) component of ultra low frequency (ULF) "brainwaves" appears to enable perfect fitting with narrowed limits of conscious capacity in normal awake states and very extended limits in altered states of consciousness - due to the biophysical relativistic mechanism of dilated subjective time base. An additional complex low-dielectric (epsilon r approximately 1) structure is also necessary in these processes. This structure can be related to a displaced (from the body) part of acupuncture ionic system which can conduct ULF brainwave currents approximately 10(-7) A, inside the conductive channels of the initial ionic concentration approximately 10(-15) cm-3, with a tendency of deterioration during a period of approximately 1 hour. It provides an extraordinary biophysical basis for traditional psychology, including trans-personal experiences down to the ultimate state of thoughtless consciousness. Notions, such as "qi", "subtle body", and "causal body", are physically inevitably associated with ions, displaced (from the body) part of acupuncture ionic structure, and in it embedded an EM component of ULF brainwaves, respectively.

Acupuncture Therapy↗
PubMed1989

[The effects of conscious and subconscious processing of hostility- or friendliness-related words on the personality impression of others].

Four experiments were conducted to investigate how the prior processing of trait relevant information influenced upon the impression formation. Twenty university students participated in each experiment. First subjects performed a cognitive task in which they processed hostility (Exp. I, II) or friendliness (Exp. III, IV) related words, consciously (Exp. I, III) or subconsciously (Exp. II, IV). In another ostensibly unrelated task, subjects rated a stimulus person on several trait scales based on an ambiguous behavioral description, regarding to hostility (Exp. I, II) or friendliness (Exp. III, IV). It was shown that the more hostility words subjects processed either consciously or subconsciously, the more extreme and negative ratings they yielded. As for friendliness words, however, such effects were found only when they were subconsciously processed, not when they were consciously processed. It was argued that conscious processing was affected by positiveness or negativeness of trait words, but subconscious processing was not.

Adult↗
PubMed1998

[The initial loss of consciousness in spontaneous subarachnoid hemorrhage. What does it mean?].

BACKGROUND AND PURPOSE: Poor outcome and rebleeding, after admission to hospital of patients with spontaneous subarachnoid hemorrhage (SAH) has been found to be predicted by loss of consciousness at ictus (LOCi). In this study, we assessed the clinical and neuro-radiological significance of the LOCi in non-traumatic SAH. PATIENTS AND METHODS: The authors retrospectively studied 102 patients with SAH admitted to S. João Hospital between January 1, 1989 and December 31, 1992, who were divided into two groups with and without LOCi and compared according to clinical and imaging features. RESULTS: Loss of consciousness at ictus was statistically associated with an age over 52 years (odds ratio, 2.9; 95% confidence interval, 1.1-7.8); a Hunt and Hess Scale score > ou = 3 (4.4; 1.6-12.3); finding of subarachnoid blood on initial cranial CT scan (5.5; 1.4-26.3); existence of aneurysm (3.4; 1.3-8.9); a Glasgow Outcome Scale score > ou = 3 (4.69; 1.6-14.1). A poor clinical condition on admission (5.2;1.8-14.5) and existence of aneurysm (4.1; 1.6-10.6) were the only two findings shown to have an independent power of significant association with loss of consciousness at ictus, using logistic regression analysis, with LOCi as a dependent variable. CONCLUSIONS: In this study, LOCi has independent predictive power for a poor neurologic condition on admission and for the finding of aneurysm on angiogram. Loss of consciousness at ictus may be explained by the direct impact of the initial hemorrhage on the brain from a large tear in the aneurysmal wall, causing a quick rise in intracranial pressure (with LOCi) but a relatively short bleeding time.

Brain↗
PubMed2000

[A case of Wernicke-Korsakoff syndrome with dramatic improvement in consciousness immediately after intravenous infusion of thiamine].

A 68-year-old man was hospitalized on March 4, 1998 for disturbances in consciousness. In 1995, he had received proximal subtotal gastrectomy and reconstructive surgery of the jejunal interposition for gastric cancer. Thereafter he had been taking enough food without the habit of taking liquor. In October 1997, his short term memory was becoming gradually worse. On February 12, 1998, he suffered from numbness in the feet, and then dysphagia, unsteady gait, and diplopia developed gradually. On February 26, brain MRI showed no abnormalities. On March 3, he had a fever of 38.5 degrees C and his consciousness became unclear. Neurological examination revealed semi-coma, total ophthalmoplegia, and absence of doll's eye movement. Deep tendon reflexes were absent. The serum thiamine level was 9 ng/ml (normal range: 20-50). Brain MRI demonstrated symmetrical high intensity lesions in the periaqueductal area of the midbrain, dorsomedial nuclei of bilateral thalami, and vestibular nuclei. About 30 seconds after intravenous infusion of thiamine, his consciousness improved dramatically, but returned to semi-coma after about two minutes. Wernicke-Korsakoff syndrome usually occurs acutely. In the present case, however, the disease showed slow onset, chronic progression, and then rapid worsening after fever. Reconstructive surgery of the jejunal interposition might have caused the slow onset of Wernicke-Korsakoff syndrome, and fever might have facilitated the rapid progression of the disease. An immediate high concentration of thiamine modifies the kinetics of acetylcholine receptor ion channels, thereby maintaining wakefulness, and the level of consciousness may change dramatically.

Aged↗
PubMed2001

Goldmann applanation tonometry in the conscious rat.

PURPOSE: To determine whether the Goldmann applanation tonometer can be modified to measure intraocular pressure (IOP) in the conscious rat. METHODS: In anesthetized rats Goldmann tonometers were tested that had reduced biprism angles in the applanating tips and reduced weights in the tonometer body from those used in humans and species with similar size eyes. Tonometers with tips with biprism angles of 48 degrees and an applied weight of 25 mg per Goldmann scale division (2 g full scale) were calibrated for the rat against manometrically measured IOP. Tonometers, thus modified, were then used in conscious, unsedated rats. RESULTS: In conscious rats the measured mean Goldmann value was 15.5 +/- 0.6 mm Hg (confidence interval = 14.1, 16.6 mm Hg). This was the plateau level reached after the repeated applanations (approximately 10) required to eliminate an artifactual decline in initial Goldmann readings, which was larger than that in humans. CONCLUSIONS: The Goldmann applanation tonometer was modified to measure IOP in the conscious, unsedated rat. This instrument, the standard for measuring this key physiological parameter in the human eye, can now be applied to the laboratory rat. This may advance the use of this important animal as a model in IOP and glaucoma research.

Animals↗
PubMed1975

[Consciousness disorders in focal lesions of the right and left cerebral hemispheres].

In the light of modern concepts of functional asymmetry in the human brain, the authors analyse paroxysmal conditions of changed consciousness which occurred in 160 patients with lesions of the hemispheres due to brain tumors (75 patients) and in epilepsy (85 patients). It is shown that certain forms of changed consciousness are characteristic of disorders of the right and left hemispheres in right-handedness. This clinical fact is taken as a basis for the assumption that in the formation of consciousness both hemispheres in different ways play a certain role and they provide different "formating" kinds of consciousness: the right hemisphere--a direct perception or a sensory perception of the environment and itself, the left--process of abstract perception based on speech, symbols, semantics.

Brain Neoplasms↗
PubMed2002

Reflective self-awareness and conscious states: PET evidence for a common midline parietofrontal core.

A recent meta-analysis has shown precuneus, angular gyri, anterior cingulate gyri, and adjacent structures to be highly metabolically active in support of resting consciousness. We hypothesize that these regions constitute a functional network of reflective self-awareness thought to be a core function of consciousness. Seven normal volunteers were asked to think intensely on how they would describe the personality traits and physical appearance of themselves and a neutral reference person known to all the subjects (the Danish Queen). During each of the four conditions cerebral blood flow distribution was measured by the intravenous H(2)(15)O PET scanning technique. During scanning, no sensory or motor activity was intended. After each scan, the subjects reported the contents of their thoughts during the scan to ascertain that the instructions had been followed. The results confirmed our hypothesis: Statistical parametric mapping showed differential activity in precuneus and angular gyri during reflection on own personality traits and in anterior cingulate gyri during reflection on own physical traits. Connectivity analysis of synchrony showed these regions to be functionally connected during reflective self-awareness. The commonality between the neural networks of the resting conscious state and self-awareness reflects the phenomenological concept of a fundamental contribution of reflective self-awareness to the contents and coherence of the conscious state.

Adult↗
PubMed2004

[Peculiarities of interhemisphere interaction at different levels of consciousness].

Transition from wakefulness to drowsiness was used as a model of a gradual decrease in the consciousness level. Subjects' self-reported changes in the contents of consciousness, namely: the intensity and quality of involuntary mental processes, served as an indicator of the consciousness level. Each observed level of consciousness was shown to be characterised by a certain EEG profile. It was also shown that the state in which the subject signals of a slowdown of the "internal speech" or the "lapse of thoughts" corresponds to the lowest level of activation. In this case, the interhemisphere connections involving the main mechanism of cognitive information transmission, i.e. the EEG high-frequency rhythms, becomes suppressed.

Brain↗
PubMed2005

[EEG frequency: amplitude characteristics at different levels of consciousness].

Relationship was studied between the level of consciousness and the level of the brain activation. State of transition from wakefulness to drowsiness was used as a model of gradual decrease in the level of consciousness. A change in the intensity and quality of appearing involuntarily mental processes served as an index of the level of consciousness as determined by subjects' self-reports. It was found that a certain EEG profile corresponded to each level of consciousness under study. The data obtained showed that the lowest level of activation corresponded to a state in which a subject develops inhibition of "internal speech", "failure of thoughts". In this case, the dynamics of the EEG high frequency rhythm changes was possibly related to the mechanism of transmission of cognitive information.

Adult↗
PubMedDate not supplied

[A psychophysiological approach toward the problem of consciousness].

Psychophysiological analysis of the relationship between the level of consciousness and the brain activation permitted an identification of three levels of consciousness at the transition from wakefulness to sleep. A change in the intensity and quality of involuntarily mental processes served as an index of the level of consciousness according to subjects' self-reports. It was found that a certain EEG profile corresponds to each level of consciousness under study. Data obtained showed that the lowest level of activation corresponds to a state in which a subject notes an inhibition of "internal speech", "failure of thoughts". At this case the dynamics of the EEG high frequency rhythm changes which is possibly related to the mechanism of transmission of cognitive information.

Adolescent↗
PubMedDate not supplied

[Field of consciousness and level of anticipation].

Man's main activity is to live his future, to shape it, to direct it and to constantly adapt it to circumstances. This phenomenon is "anticipation". As far as this perspective is adopted, the field of consciousness appears narrow but extremely changing. The unconscious does not exist in so far as a territory, a structure or an apparatus. Unconscious has not to be a substantive but only an adjective. Data of consciousness remain unconscious or subconscious during the main part of the time. Moreover, the subject may live his future at various levels, from a biologic one till transcendence and the data of consciousness much depend on this level. All pathologic states involve an impoverishment of the field of consciousness. This limitation is sometimes transitory, for example in psychomotor epilepsy and above all in various neuroses. The patient then undergoes a sudden "regressing dive", which may be very brief and remain unseen by observer. During the "dive", he can only anticipate rudimentary and maladjusted behaviours, neurotic symptoms. In conversion hysteria, the regression is more durable but partial. Psychotic limitation, the level of which is variable, remains as long as psychosis itself.

Adaptation, Psychological↗
PubMed1991

[Conscious and unconscious acoustic perception during general anesthesia].

The possibility of processing sensory information during general anesthesia and the ability to recall it postoperatively is of major ethical, medical and even theoretical importance. Auditory stimuli especially are perceived intraoperatively and remembered postoperatively. Neuropsychological experiments indicate that sensory information can be processed and recalled both at a conscious and at an unconscious level. Therefore, we have to distinguish between explicit and implicit memory. Explicit memory is characterized by an active and conscious recall of space- and time-related events, i.e., episodes in a person's life. In contrast, implicit memory recalls passively and unconsciously without being related to space and time, i.e., language and general knowledge. Experimental results from amnesic patients indicate that these two memory systems work independently from each other. Even when explicit memory is grossly impaired the function of the implicit memory may still be completely preserved. Various studies on intraoperative awareness show that explicit memory is widely eliminated during general anesthesia. The incidence of conscious awareness that can be actively recalled postoperatively is reported to be 1-3%. In contrast, the implicit memory function can be partially preserved. When implicit memory tasks or hypnosis are employed, traces of unconscious memory of intraoperative auditory information can be shown in 20-30% of the patients. These observations are of important clinical relevance, because the unconsciously recalled information about the intraoperative procedure may have a negative influence on the patient's postoperative recovery and well-being. So far it is still not known which anesthetics most reliably suppress auditory perception and conscious and unconscious memory during the intraoperative period. Therefore, future studies should focus on several different points. The anesthetic state should be defined exactly and the functional state of the auditory modality should be monitored when auditory information is presented to the patients. The recollection of intraoperative events should be investigated using implicit memory tests, because these are regarded as more sensitive than explicit memory tests.

Anesthesia, General↗
PubMed1991

[Consciousness functions in psychoses. Concepts, empirism and hypotheses].

Schizophrenia may be described as a disease where speech, bodily language and social responsiveness are obvious expressions of a deteriorated ability to interact with the surroundings in a precise and relevant way. The lack of precision and relevance pertains to perception and recall as well as communication and action. The deficient potential for activation of the prefrontal cerebral cortex is a neurobiological correlate to the lesion of precise and relevant planning and expression. Impairment of formal thought and language in schizophrenia are suggested to result from a developmental disorder pertaining to language and concept formation (apperception). In reactive psychoses with dissociative disturbances of consciousness there is an inefficient capacity for adapting to external reality; thus relevant conscious planning and interaction with the outside world are impaired. Clinically a distractibility of a tematic nature ensues. Except for catastrophic events, psychotic reactions cannot be predicted from analysis of the actual experience--neither concerning the external nor the internal aspects of conscious awareness. Sometimes, however, previous events relating to the formation of the self may add explanatory value to the analysis of reactive psychosis. In some cases biological predisposition is the decisive determinant. The normal discrimination between sense-perception and imagination has a counterpart in the dichotomy of awareness of the outside world versus awareness of the self. The following are examples of psychotic experience where the normal ability for dichotomic discrimination may be damaged: Illusions of affect, hallucinations, Schneider's first rank symptoms, "Anwesenheit" and consciousness of time.(ABSTRACT TRUNCATED AT 250 WORDS)

Consciousness↗
PubMed1989

[Acute and subacute organic psychoses with altered consciousness. Attempt at classifying severity].

We have retrospectively investigated 71 patients with ICD-9 diagnoses 293.0 or 293.1, who were treated in our clinic in 1987, with respect to the maximum severity of altered consciousness. On the basis of an available neurological grading into "clouding of consciousness", "confusional state", "delirium", "stupor", and "coma", and from knowledge of the underlying somatic disease, we have developed prognostic criteria: Disorders of heart and circulation associated with acute organic mental disorder (with altered consciousness) carry a fair prognosis for recovery of the mental disorder in approximately two-thirds of all patients affected, even in advanced age. The same statement is valid with respect to drug-induced acute organic mental disorders, whereas most cases of cerebrovascular disorders with mental disturbances proceed to chronic forms of organic mental disorder. We believe that the clinical descriptive terms referred to above allow easy grading of states of acutely/subacutely altered consciousness, thereby providing prognostic criteria for the course of the disease.

Adult↗
PubMed1989

[Epidemiological research on drinking of women. (Part 2). Effects of consciousness or attitude concerning about drinking and life events on drinking behavior].

Women drinkers are on the increase, in recent 20 years, according to greater participation of women in public affairs and the change of life style and so on. So, the consciousness or attitude of drinking or alcoholic beverages among women have been changed by the new customs of drinking. In this paper the relationship between women drinking behavior and their consciousness of drinking or life events, was investigated statistically using the data of sending questionnaires concerning about drinking behavior, consciousness and drinking history in Kusatsu city. The subject of investigation was 4,105 women who were aged 30 years and more, and 1,650 answers were available. Then the following findings were obtained; 1) The pattern of consumption of alcoholic beverages changed fairly from 1960, but in recent years, it seems to keep balance and yearly consumption of pure alcohol per adult has leveled off about 8 l. 2) Distribution of PAC (Pure Alcohol Consumption per year) of women exceeding the limit of a liter per year was against the logarithmic normal curve. The median value of PAC of women in Kusatsu was estimated about 0.55 l, and it seemed to be smaller than that of men. QFI (Quantity-Frequency Index) of women was large among those who were full-time workers being in their thirties and forties, and had mother of regular drinker who drank once and more a week. 3) The estimated ratio of excessive drinkers among women by adopting Ledermann's model was larger than the practical ratio. For estimating the women excessive drinkers accurately, it is necessary to use exact P.A.C. of women. 4) The 20 opinions concerning with drinking or alcoholic beverages were grouped into four basic consciousness by using the method of factor analysis. The 1st was 'necessity or values' of drinking, the 2nd was 'method or manner' for taking the pleasure of drinking and of correct drinking, the 3rd was 'regulation' of alcoholic slot machine, minor drinking or drunk and the 4th was 'harmfulness' of alcohol. The 'necessity' promoted drinking and the 'method' also promoted correct drinking but controlled QFI. The 'regulation' was common to all of women and the 'harmfulness' controlled drinking. 5) The life events, for women, such as entrance into a school of higher grade, employment, social activities, divorce, reemployment promoted drinking of women. And retirement, child birth, serious illness controlled drinking of women. Marriage promoted drinking when her husband was regular drinker or when she was infrequent or light drinker before marriage.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1989

Negative hallucinations, other irretrievable experiences and two functions of consciousness.

After providing a psychodynamic exploration of negative hallucinations in four clinical cases, the focus of this paper was broadened in an attempt to understand the mechanism of negative hallucination. To this end, after defining the term 'irretrievable experiences', two other examples--preconscious perceptions and infantile amnesia, both analogues to negative hallucination--were examined. A discussion followed concerning two types of 'consciousness': 'consciousness' as a synonym for 'awareness' and 'consciousness' as a distinct psychological state. Next, the role of different functions of each sort of consciousness in the processes of conferring, fixing and retrieving mental contents within particular categories of experience was taken up. Finally, integrating developmental aspects of these same functions, explanations were offered regarding the mechanisms involved in preconscious perception, infantile amnesia and negative hallucinations.

Adult↗
PubMed1978

[Loss of consciousness in migraine].

The author conducted a clinico-electrophysiological study of 350 patients with migraine. In 12.5% of the patients there were cases with a loss of consciousness. The conclusion is made that in combination of one attack of symptoms of migraine and epilepsy they have one pathogenesis: vasomotor disorders evoking both migrainose crises and syncopes with a convulsive syndrome. Quite typical of such conditions are precursors, massive vegetative disturbances, a tonic character of the convulsions. A loss of consciousness in the intra-attack period may be assessed as a syncope, mainly of orthostatic and vaso-vagal type; a loss of consciousness during the attack--as a syncope connected with migrainose disorders of cerebral hemodynamics. In alternation of migrainose and epileptical attacks it is claimed that there is a combination of 2 diseases. The conclusion is made that a loss of consciousness in migraine and epilepsy are different not only by clinical signs, but by its pathogenesis. This fact determines the preventive therapy of both diseases.

Adolescent↗