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Episodic memory and autonoetic consciousness: a first-person approach.

Episodic memory is identified with autonoetic consciousness, which gives rise to remembering in the sense of self-recollection in the mental re-enactment of previous events at which one was present. Autonoetic consciousness is distinguished from noetic consciousness, which gives rise to awareness of the past that is limited to feelings of familiarity or knowing. Noetic consciousness is identified not with episodic but with semantic memory, which involves general knowledge. A recently developed approach to episodic memory makes use of 'first-person' reports of remembering and knowing. Studies using this approach have revealed many independent variables that selectively affect remembering and others that selectively affect knowing. These studies can also be interpreted in terms of distinctiveness and fluency of processing. Remembering and knowing do not correspond with degrees of confidence in memory. Nor does remembering always control the memory response. There is evidence that remembering is selectively impaired in various populations, including not only amnesic patients and older adults but also adults with Asperger's syndrome. This first-person approach to episodic memory represents one way in which that most elusive aspect of consciousness, its subjectivity, can be investigated scientifically. The two kinds of conscious experiences can be manipulated experimentally in ways that are systematic, replicable and intelligible theoretically.

Asperger Syndrome↗

Anxiety and self-consciousness in patients with minor facial lacerations.

BACKGROUND: Although minor facial injuries are relatively common, their psychological impact is an area neglected in the literature. For physiologically major injuries (such as facial cancers, burns and fractures), the face has been suggested to be a psychologically significant area of the body and disfigurement has been found to have numerous potential social consequences for patients. AIMS: This paper reports the findings of an inquiry that explored the psychological impact of minor facial injuries and the influence of patient and scar characteristics in relation to self-consciousness and anxiety levels. METHOD: Data were collected in 2001 in an accident and emergency unit from patients with a visible laceration over 1.5 cm that was treatable in an outpatient setting. The Derriford Appearance Scale (with general and social self-consciousness subscales) and the State-Trait Anxiety Inventory were administered to 63 patients 1 week later; data on 50 patients were also available 6 months after the injury. RESULTS: Larger scar size, living alone and aetiology of injury were significantly related to self-consciousness and anxiety levels, although gender, age, socio-economic group, location of scar, satisfaction with appearance and number of scars were not. General self-consciousness improved at 6 months but social self-consciousness and anxiety remained the same. Patient factors were not related to changes in general self-consciousness over time. CONCLUSIONS: Minor facial scars can have significant psychological impact for some people. Awareness training for health professionals, social skills training for affected patients and a patient information leaflet are recommended.

Adaptation, Psychological↗

Kinetic constants for blood-brain barrier amino acid transport in conscious rats.

The kinetic constants for large neutral amino acid (LNAA) transport across the blood-brain barrier (BBB) of conscious rats were determined in four brain regions: cortex, caudate-putamen, hippocampus, and thalamus-hypothalamus. Indwelling external carotid artery catheters allowed for single-bolus (200 microliters) injections directly into the arterial system of unanesthetized and lightly restrained animals. Our results showed lower brain uptake index values for conscious rats compared to previous reports for anesthetized animals which are consistent with higher rates of cerebral blood flow in the conscious animals. Km values were lower in the conscious animals and ranged from 29% to 87% of the Km values in pentobarbital-anesthetized animals whereas the KD values were about twofold higher in the conscious animals. No apparent regional differences were observed. Influx rates were determined which take into consideration flow rates and plasma amino acid concentrations. Our results showed an average amino acid influx value of 5.2 nmol/min/g, which is 53% higher than the average influx in pentobarbital-anesthetized animals. The present results in conscious animals regarding the low Km of LNAA transport across the BBB lend further support to the importance of fluctuations in plasma amino acid concentrations and LNAA transport competitive effects on brain amino acid availability.

Amino Acids↗

Impairment of consciousness during epileptic seizures with special reference to neuronal mechanisms.

Two neuronal structures, i.e., the cerebral cortex and the subcortical structures, were shown by clinical observations to be involved in maintaining consciousness. The alteration of consciousness during epileptic seizures is discussed with respect to these findings: Alterations of consciousness during epileptic seizures may be produced by subcortical, i.e., reticular formation, and/or cortical dysfunction followed by excessive, hypersynchronous neuronal discharges. An impairment of consciousness during absence seizures may be due mainly to cortical dysfunction; during complex partial seizures (CPS), it may be due to dysfunctional subcortical neuronal structures. The mechanisms underlying an alteration of consciousness are defined as causing "irritative" functional disturbances and/or as having "inhibitory" effects on consciousness-related structures.

Brain↗

A functional view of consciousness and its relations in brain.

Consciousness is seen as evolving jointly with plasticity, self-direction, and autonomy. Its main function is interpreted as the partially autonomous direction of behavioral living in accordance with a vast system of plastic patterns of inner construction, and the development of these--all in the service of a central concern with widely-perceived global well-being. Its central constituents are: conscious awareness itself; sensations and images of sensory bombardment; active development and utilization of inner constructions; and active direction of attention, actions, and behavior. Consciousness operates by the partially autonomous feedback redirection of activation-energization in response to a global distribution of neurobiological flags and states. Central qualities of conscious experience are addressed from this view. Consciousness may act towards an overall principle of minimization. Contrasting its existentially observable manifestations and its neurobiological correspondences provides foundations for five basic views of the fundamental nature of consciousness and its relation to brain.

Animals↗

Postprandial hemodynamics in the conscious rat.

The postprandial intestinal hyperemia was studied in conscious and anesthetized rats using the radioactive microsphere technique. Carbohydrate, protein, lipid, and mixed meals, and the vehicle (Tyrode's solution), were placed in the stomach via a gastrostomy tube. In conscious rats, blood flow increased by 40-80% in the duodenum and jejunum 1 h after either a carbohydrate, lipid, protein, or mixed meal. Tyrode's solution produced a comparable hyperemia. Blood flow in the distal bowel segments (ileum, cecum, and colon) was significantly increased only by Tyrode's solution and the carbohydrate meal. The proximal intestinal hyperemia produced by the mixed meal in conscious animals was significantly attenuated by vagotomy yet unaltered by atropine pretreatment. In contrast to the results obtained from conscious rats, the mixed meal did not significantly alter intestinal blood flow in anesthetized animals. The results of this study indicate that the postprandial intestinal hyperemia is much greater in conscious than anesthetized animals. This difference may result from the higher resting blood flows in the latter group. The hyperemic response in conscious animals may be mediated by the vagus nerve.

Animals↗

Right coronary autoregulation in conscious, chronically instrumented dogs.

Right coronary (RC) autoregulation and right ventricular (RV) function were assessed in conscious dogs, chronically instrumented to measure RC flow and RC pressure (RCP) as a hydraulic occluder on the RC was inflated. Dogs were then anesthetized, and RC autoregulation and RV function were again assessed. In the conscious state, moderate RC autoregulation was present with closed loop gains (Gc) of 0.59-0.27 as RCP was reduced from 100 to 40 mmHg. In the anesthetized state, Gc was not significantly less than in the conscious state at RCP >50 mmHg. The range and potency of RV autoregulation were greater in both groups than for previously reported findings in anesthetized dogs with RC perfused by an extracorporeal system. RV contractile function was well maintained in conscious and anesthetized dogs at RCP >45 mmHg. We conclude the following: 1) modest RC autoregulation is present in the conscious dog, 2) anesthesia limits the range but not the degree of RC autoregulation, 3) extracorporeal perfusion systems appear to depress RC autoregulation, and 4) RV contractile function remains constant in both conscious and anesthetized dogs until RCP falls below 50 mmHg.

Anesthesia, General↗

Anesthetic inhibition in ischemic and nonischemic murine heart: comparison with conscious echocardiographic approach.

It is well known that the level of anesthesia obtained by intraperitoneal injection is variable and may alter cardiac function. In this study, we compared the effects of different anesthetics on cardiac function with the conscious state using high-resolution two-dimensional echocardiography in nonischemic and ischemic mice. Eighty-four mice were tested before and after surgery with ligation of the coronary artery. All 84 mice were studied in the conscious state and under high-dose intraperitoneal anesthesia. Twenty-two of 84 mice were studied under low-dose intraperitoneal anesthesia. Another 22 mice were also studied under gas anesthesia and spontaneous breathing. Experiments in the conscious state were performed by two investigators before the administration of anesthesia: one investigator held the animal and the transducer and the other operated the ultrasound equipment. Left ventricular systolic function was measured, and measurements obtained after surgery were compared with infarcted areas assessed by histological staining. Results showed that both high- and low-dose intraperitoneal anesthesia significantly reduced heart rates and left ventricular contractility in both pre- and postsurgical mice as opposed to conscious mice (P < 0.01). There were significantly higher correlation coefficients between mean fractional area change (FAC) and infarcted area in conscious state compared with high-dose intraperitoneal anesthesia (P < 0.05). The correlation coefficient between FAC and infarcted area during gas anesthesia was also significantly higher compared with high-dose intraperitoneal anesthesia (P < 0.05). In conclusion, conscious experiments or the use of gas anesthesia is preferred for echocardiographic assessment of cardiac function in mice because intraperitoneal injection significantly induces a significant reduction in heart rate and left ventricular systolic function.

Anesthetics, Inhalation↗

Extent of regulation of the heart's contractile state in the conscious dog by alteration in the frequency of contraction.

The effects of alterations in the frequency of contraction over the range from 94 to 220/min on left ventricular pressure, diameter, and dP/dt were studied in 10 dogs instrumented with ultrasonic diameter ganges and miniature pressure gauges. The same dogs were studied on separate days in the conscious state, after general anesthesia with pentobarbital Na, 30 mg/kg, and in the conscious state after pretreatment with propranolol, 3 mg/kg. End diastolic diameter was maintained constant during alterations in frequency by infusing saline intravenously. The maximum increases in peak dP/dt and dP/dt/P in the conscious state were 14 and 10%, respectively. After anesthesia, raising the frequency of contraction from 122 to 220/min caused maximum increases in peak dP/dt and dP/dt/P of 36 and 30%, respectively. In the conscious state after cardiac depression by propranolol, the maximum increases in peak dP/dt and dP/dt/P were 23 and 23%, respectively. Thus, increasing the frequency of contraction of the normal heart of the conscious dog causes only a slight inotropic effect, but this effect is significantly greater in the presence of myocardial depression produced by anesthesia with pentobarbital Na or in the conscious animal after a myocardial-depressing dose of propranolol.

Anesthesia, General↗

Links between conscious awareness and response inhibition: evidence from masked priming.

Recent results from "subliminal priming" experiments have shown that masked prime stimuli which can not be consciously perceived can trigger response activation processes, but that these response activations can later be subject to inhibition. Links between conscious awareness and response inhibition were investigated by manipulating the visibility of masked prime stimuli, from clearly visible primes to prime stimuli that were inaccessible to conscious perception. Response inhibition was observed with unperceived prime stimuli, but not for suprathreshold primes. Correlations between individual prime identification thresholds and the onset of response inhibition indicate that the absence or presence of conscious awareness can predict whether or not response inhibition is elicited. These results demonstrate qualitative differences in the effects of conscious and unconscious information. It is argued that response facilitation produced by consciously available perceptual information can counteract automatic effects of self-inhibitory motor control circuits.

Adult↗

[The effects of cognitive behavioral anger management program on self-consciousness and anger in Korean military man].

PURPOSE: The purpose of this study was to evaluate a cognitive behavioral anger management intervention in order to increase self-consciousness and decrease anger among Korean military men. METHODS: A quasi-experimental design was used for this study. Ninety two soldiers were screened for unhealthy anger expression using a questionnaire. Among them, 26 soldiers who showed unhealthy anger expression were selected for this study. They were matched by rank and assigned to either a treatment or control group. The treatment group received the intervention three consecutive times, once a week and for 120 minutes per session. Participants were assessed before and after the intervention for anger (the State-Trait Anger Scale) and self-consciousness (Self-consciousness Scale). Data was analyzed using descriptive statistics, chi- square-test, Mann-Whitney test, and Wilcox on signed rank test. RESULTS: There was no statistically significant decrease in anger or increase in self-consciousness between the two groups following treatment. However, there was a significant increase in private self-consciousness in the treatment group after the intervention(p=.006). CONCLUSION: The cognitive behavioral anger management program improves private self-consciousness in soldiers. However, Additional research is needed to explore whether long-term intervention is more effective for anger control in the military setting. The findings from this study suggest that more attention should be given to mental health care for Korean soldiers.

Adult↗

[Septic encephalopathy--prognostic value of the intensity of consciousness disorder to the outcome of sepsis].

Septic encephalopathy (SE) is a common term indicating the development of signs of progressing cerebral dysfunction and is associated with the presence of microorganisms and their toxins in the blood. Aim of this investigation was to analyze the frequency of this complication considering the consciousness disorders in quantitative sense and prognosis of the survival in patients with SE. The investigation comprised patients (n = 54) with positive hemoculture and signs of septic syndrome by the accepted criteria (fever, clinical signs of infection, respiratory frequency, heart rate, plasma lactate, oliguria). Patients with confirmed cerebral injury, hemorrhage or cerebral ischemia were excluded from the study. Lumbar punction and CT-scan of the brain were performed in all patients in order to exclude visible lesions of cerebral parenchyma and eventual presence of cerebral nervous system (CNS) infection as the causes of sepsis. Results of the investigation demonstrated that in 30 (55%) of patients existed mild consciousness disorder at the level of somnolescence, in 18 (33%) consciousness disorder at the level of sopor and in 6 (11%) consciousness disorder at the level of deep coma. Level of consciousness disorder was in positive correlation with the outcome of sepsis syndrome, which was additionally confirmed by the fact that only in the group of patients with deep coma lethal outcome was observed in 3 cases (50% of this subgroup) regardless of intensive antibiotic, metabolically active and symptomatic therapy. It can be concluded that SE syndrome has a favorable prognosis if macroscopic lesion and dissemination of microorganisms in CNS are not present, and simultaneously it represents changes in metabolic-electrolytic state with early presentation of consciousness disorders that represent clinically significant indicator for sepsis syndrome outcome.

Aged↗

[Relationship between CT findings and consciousness in patients with hypertensive putamen hemorrhage].

The authors studied 66 patients with hypertensive putamen hemorrhage and noted a close relationship between the CT classification according to the shape of the suprasellar cistern (S) and the third ventricle (III), and the state of altered consciousness: when S is not deformed and III is identified in CT images, the patient may be in a clear or confusional state; if S is not deformed but III is not identified or is packed with hematoma, consciousness may be somnolent or stuporous; if S is deformed and III is not identified or is packed with hematoma, the patient may be in a semicomatose or comatose state. However, within several hours after onset there are exceptional cases in which the states of consciousness do not correlate with the CT findings. In these cases, however, with conservative therapy the state of consciousness corresponded well with the CT findings. From the neurosurgical points of view, immediate removal of the hematoma is required when the patient's consciousness is relatively good despite of large hematoma. If at the acute stage the state of consciousness, which corresponded well with the CT findings at initial examination, has deteriorated, rebleeding or enlargement of hematoma must be suspected.

Brain↗

Impact of patient consciousness on the intensity of the do-not-resuscitate therapeutic plan.

BACKGROUND: The nature and intensity of a do-not-resuscitate therapeutic plan varies by patient. Some do-not-resuscitate therapeutic plans may include interventions directed at the withdrawal of life-sustaining therapy. OBJECTIVE: The purpose of this study was to examine the impact of patient consciousness on the nature and intensity of the do-not-resuscitate plan, and on the decision to withdraw life-sustaining therapy. METHODS: This study represents a secondary analysis of data obtained in a previous study to evaluate patient care requirements under varying intensities of do-not-resuscitate plans. Data were collected retrospectively through record review. Patients were grouped as follows, according to the intensity of the do-not-resuscitate plan: (1) all but cardiopulmonary resuscitation, (2) conservative care without cardiopulmonary resuscitation, (3) comfort only, and (4) withdrawal of life-sustaining therapy. In addition to demographic data, consciousness and illness severity were measured. Data were analyzed using descriptive statistics. RESULTS: There was a significant decrease in consciousness from admission in all groups except conservative care. The withdrawal group had the lowest average Glasgow Coma Scale scores at the time of the do-not-resuscitate designation. Multiple regression analysis was used to demonstrate a significant impact of consciousness on type of do-not-resuscitate decision, but no significant impact from age or illness severity. CONCLUSIONS: These results support previous observations that decisions to withdraw life-sustaining therapy are prompted by diminished consciousness. These results may stimulate caregivers to offer withdrawal of life-sustaining therapy as an option in patients with severely decreased consciousness and a poor prognosis for functional recovery.

APACHE↗

Safe and effective conscious sedation administered by dermatologic surgeons.

OBJECTIVE: To review the experience with conscious sedation administered by dermatologic surgeons at an academic medical center. DESIGN: Retrospective medical chart review. SETTING: Outpatient dermatologic surgery unit at an academic medical center. PATIENTS: Fifty episodes of conscious sedation in 37 patients undergoing dermatologic surgical procedures. INTERVENTION: Intravenous and inhaled conscious sedation was administered with strict monitoring during procedures. MAIN OUTCOME MEASURES: Efficacy was subjectively recorded by the administering physician and complications were recorded. RESULTS: Administration of conscious sedation by dermatologic surgeons was associated with good to excellent sedation with minimal complications. Extensive preparation and training were necessary, and strict guidelines devised by a conscious sedation task force were followed. Emergency preparedness was high, although it was not used. CONCLUSIONS: Conscious sedation can be safely and effectively administered by dermatologic surgeons in a hospital-based outpatient surgical unit after extensive training. Emergency preparedness is essential, and conservative guidelines should be followed.

Administration, Inhalation↗

The safety of conscious sedation in peritonsillar abscess drainage.

OBJECTIVE: To demonstrate the safety of conscious sedation in draining peritonsillar abscesses (PTAs). DESIGN: Children diagnosed as having a PTA in the pediatric emergency department were identified, and their medical records were retrospectively reviewed. Results of the present study were compared with those of a previous report. SETTING: A tertiary referral children's hospital pediatric emergency department. PARTICIPANTS: Ninety-one consecutive children initially evaluated in the emergency department and managed for a PTA. INTERVENTIONS: Peritonsillar abscess incision and drainage with or without sedation. A team of physicians whose activities were documented on a formal conscious-sedation record was present. Patients were monitored for major and minor complications. OUTCOME MEASURES: The primary outcome measures were major and minor complications. Secondary outcome measures were recurrence of PTA and the need for admission. RESULTS: There were 62 episodes of conscious sedation for drainage of a PTA. Among the 91 patients, 3 had a recurrence and 24 were admitted after the procedure. A previous study evaluated 30 episodes of conscious sedation for drainage of a PTA. No major complications occurred in either series. Combining the previous data with the present data produced 92 episodes of conscious sedation for drainage of a PTA. The 1-sided upper 95% confidence limit for the rate of major complications is 3.2%. CONCLUSION: Our series, when combined with previously published data, demonstrates that conscious sedation can be safely used when draining a PTA in pediatric patients.

Adolescent↗

Fluency versus conscious recollection in category-production performance: the performance of schizophrenic patients.

The purpose of this study was to investigate the relative contribution in schizophrenics of automatic processes (fluency) and conscious processes (conscious recollection) for the control of preencoded material in category production tasks. In one condition (Exclusion condition), subjects were told specifically not to produce previously presented words during the category-production task. This condition was compared with a standard category-production task in which subjects were told to produce the six first words that came to mind for a semantic category (Inclusion condition). In the inclusion condition, the effects of conscious control and automatic processes operated in the same direction, whereas in the exclusion condition automatic influences and conscious control were opposed. A recognition task followed the category-production tasks. Since the exclusion condition required conscious control of encoded items, we hypothesized that schizophrenic patients would be less able than control subjects to avoid producing study list items. These results indicated that schizophrenics' performance differed from these of control subjects in the exclusion condition but not in inclusion condition. Recognition performance was similar in both the schizophrenic and the control groups. These results suggest a defective conscious control in schizophrenic patients and confirm the data from the literature on explicit memory in these patients.

Female↗

Anesthesia, neural information processing, and conscious awareness.

Possible systemic effects of general anesthetic agents on neural information processing are discussed in the context of the thalamocortical suppression hypothesis presented by Drs. Alkire, Haier, and Fallon (this issue) in their PET study of the anesthetized state. Accounts of the neural requisites of consciousness fall into two broad categories. Neuronal-specificity theories postulate that activity in particular neural populations is sufficient for conscious awareness, while process-coherence theories postulate that particular organizations of neural activity are sufficient. Accounts of anesthetic narcosis, on the other hand, explain losses of consciousness in terms of neural signal-suppressions, transmission blocks, and the disruptions of signal interpretation. While signal-suppression may account for the actions of some anesthetic agents, the existence of anesthetics, such as choralose, that cause both loss of consciousness and elevated discharge rates, is problematic for a general theory of narcosis that is based purely on signal suppression and transmission-block. However, anesthetic agents also alter relative firing rates and temporal discharge patterns that may disrupt the coherence of neural signals and the functioning of the neural networks that interpret them. It is difficult at present, solely on the basis of regional brain metabolic rates, to test process-coherence hypotheses regarding organizational requisites for conscious awareness. While these pioneering PET studies have great merit as panoramic windows of mind-brain correlates, wider ranges of theory and empirical evidence need to be brought into the formulation of truly comprehensive theories of consciousness and anesthesia.

Adolescent↗