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PubMed2006

The role of conscious reasoning and intuition in moral judgment: testing three principles of harm.

Is moral judgment accomplished by intuition or conscious reasoning? An answer demands a detailed account of the moral principles in question. We investigated three principles that guide moral judgments: (a) Harm caused by action is worse than harm caused by omission, (b) harm intended as the means to a goal is worse than harm foreseen as the side effect of a goal, and (c) harm involving physical contact with the victim is worse than harm involving no physical contact. Asking whether these principles are invoked to explain moral judgments, we found that subjects generally appealed to the first and third principles in their justifications, but not to the second. This finding has significance for methods and theories of moral psychology: The moral principles used in judgment must be directly compared with those articulated in justification, and doing so shows that some moral principles are available to conscious reasoning whereas others are not.

Adult↗
PubMed1993

Alpha 1 and alpha 2-adrenergic control of large and small coronary arteries during exercise in conscious dogs under beta-blockade.

The aim of this study was to determine the relative roles of alpha 1-and alpha 2-adrenoceptors at the level of large epicardial and small resistance coronary arteries when sympathetic tone is increased by exercise in conscious dogs. The responses of left circumflex coronary artery diameter and blood flow were investigated at rest and during graded treadmill exercise (5, 10 and 12 km/h) in six chronically instrumented dogs during control conditions (saline) and after administration of propranolol (1 mg/kg) either alone or in combination with either prazosin (50 micrograms/kg), or idazoxan (300 micrograms/kg), or the association of prazosin+idazoxan (same doses). In control conditions, graded treadmill exercise resulted in a progressive increase in coronary artery diameter (+3.8 +/- 0.6% from 3479 +/- 80 microns) and in a decrease in coronary vascular resistance (-46.0 +/- 4.5% from 8.49 +/- 1.51 mmHg/cm/s). Propranolol significantly constricted large (-4.4 +/- 0.6% from 3486 +/- 87 microns) and limited dilation of small coronary arteries during exercise. These coronary effects of propranolol remained unchanged following additional alpha 2-adrenoceptor blockade by idazoxan but were abolished following alpha 1-adrenoceptor blockade by prazosin, given either alone or combined with idazoxan. Thus, alpha 1- but not alpha 2-adrenoceptors are responsible for propranolol-induced constriction of large coronary arteries and limitation of small coronary arteries dilation during exercise in conscious dogs.

Adrenergic beta-Antagonists↗
PubMed1994

Effect of sodium metabisulphite on bronchial blood flow in conscious sheep: pharmacological modulation.

1. Sodium metabisulphite (MBS) can induce bronchoconstriction in patients with asthma. We investigated the effects of MBS aerosol on bronchial blood velocity (Vbr) and pulmonary resistance in intubated conscious sheep. 2. Bronchial blood velocity was measured by implanting a 20 MHz ultrasonic Doppler flow probe on the common bronchial branch of the bronchoesophageal artery. 3. Inhaled MBS induced a dose-dependent, transient increase in Vbr lasting for a few minutes without any changes in aortic and pulmonary artery pressures. There was some tachyphylaxis of the Vbr response to successive inhalations of MBS. 4. The cholinoceptor antagonist, ipratropium bromide and the H1 and H2 histamine antagonists, chlorpheniramine and cimetidine, had no significant effect on MBS-induced increase on Vbr. The loop diuretic, frusemide, and the anti-inflammatory drug, nedocromil sodium, which both inhibit MBS-induced bronchoconstriction in patients with asthma, were also without effect. 5. We conclude that MBS induces bronchial vasodilatation in conscious sheep, and that this effect is not dependent on the release of histamine or other mediators, or an activation of cholinergic pathways.

Administration, Inhalation↗
PubMed1996

Effects of dexamethasone and SB 209670 on the regional haemodynamic responses to lipopolysaccharide in conscious rats.

1. Male (350-450 g) Long Evans rats were chronically instrumented to permit regional haemodynamics to be monitored in the conscious state. In the first experiment, either saline (0.4 ml h-1) or dexamethasone (3 mg kg-1, 125 micrograms kg-1 h-1) was infused continuously for 24 h, before co-infusion of lipopolysaccharide of (LPS, 150 micrograms kg-1 h-1) for 24 h. Dexamethasone prevented the delayed (5-24 h) fall in mean arterial blood pressure (MAP) and the renal and hindquarters vasodilatation seen with LPS infusion alone, but not the initial (about 2 h) fall in MAP or renal vasodilatation. However, at this dose, dexamethasone itself caused a significant rise in MAP and regional vasoconstrictions. 2. In the second experiment, dexamethasone at a lower dose (12.5 micrograms kg-1 h-1) had only slight pressor and vasoconstrictor effects. However, in its presence, infusion of LPS caused a substantial and progressive rise in MAP (maximum at 8 h, +32 +/- 3 mmHg) together with persistent mesenteric and hindquarters vasoconstriction and a transient renal vasodilatation. 3. In the third experiment, the non-selective endothelin antagonist, SB 209670 (600 micrograms kg-1 h-1), blocked the slight pressor and regional vasoconstrictor effects of the lower dose of dexamethasone. Furthermore, in the presence of dexamethasone and SB 209670, infusion of LPS caused marked, but transient hypotension (nadir at 5 h, -24 +/- 2 mmHg) and renal and mesenteric vasodilatation. 4. At the end of all experimental protocols, sequential administration of the AT1-receptor antagonist, losartan, followed by the V1-receptor antagonist, (+)-(CH2)5-O-Me-Tyr, vasopressin, caused effects indicating a variable involvement of angiotensin and vasopressin in the maintenance of cardiovascular status. 5. Collectively, the results indicate that, in the conscious rat, dexamethasone interacts with vasoconstrictor and vasodilator mechanisms, and hence its influence on the haemodynamic responses to LPS cannot be attributed, simply, to inhibition of the activity of inducible nitric oxide synthase and/or cyclo-oxygenase-2.

Angiotensin Receptor Antagonists↗
PubMed1996

Role of bradykinin receptors in the renal effects of inhibition of angiotensin converting enzyme and endopeptidases 24.11 and 24.15 in conscious rabbits.

1. We tested the effects on systemic haemodynamics and renal function, of inhibition of endopeptidase (EP) 24.15 (E.C. 3.4.24.15), in conscious uninephrectomized rabbits in which the activities of angiotensin converting enzyme (ACE, E.C. 3.4.15.1) and neutral endopeptidase (EP 24.11, E.C. 3.4.24.11) were already inhibited. To test the role of bradykinin B2-receptors in mediating the effects following inhibition of these enzymes, the antagonist Hoe 140 was used. 2. Hoe 140 (0.1 mg kg-1, i.v.) did not affect resting mean arterial pressure or heart rate, but antagonized the depressor effect of right atrial administration of bradykinin. The dose-response curve for bradykinin was shifted more than 1000 fold to the right for more than 4 h. Hoe 140 approximately doubled resting urine flow and increased fractional Na+ excretion from 4.2 to 6.0%; consistent with the hypothesis that it exerts a partial agonist effect on the kidney. 3. Combined inhibition of ACE (captopril; 0.25 mg kg-1 plus 0.2 mg kg-1h-1) and EP 24.11 (SCH 39370; 3 mg kg-1 plus 3 mg kg-1h-1) was followed by a sustained reduction in arterial pressure (-6 +/- 2 mmHg) and increase in heart rate (35 +/- 7 beats min-1). There was a small increase in renal blood flow (by 6.5 +/- 3.2% relative to vehicle-treatment) without a change in glomerular filtration rate, and about a 150% increase in Na+ excretion. Hoe 140 (0.1 mg kg-1, i.v.) pretreatment did not influence the renal effects of captopril and SCH 39370, although it did appear to blunt their hypotensive and tachycardic effects. 4. When EP 24.15 was inhibited with N-[1-(R,S)-carboxy-3-phenylpropyl]-Ala-Ala-Tyr-p-aminobenzoate (cFP-AAY-pAB; 5 mg kg-1 plus 3 mg kg-1h-1, i.v.) in rabbits pretreated with captopril and SCH 39370, no changes in systemic haemodynamics or renal function were observed. 5. We concluded that in conscious uninephrectomized rabbits, EP 24.15 does not play a major role in modulating renal function, at least under conditions where ACE and EP 24.11 are already inhibited. In contrast, ACE and/or EP 24.11 do modulate renal function in this model, but their influences are mediated chiefly through metabolism of peptides other than bradykinin.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1994

Prolonged impaired consciousness in basilar artery migraine.

Basilar artery migraine is a distinctive disorder characterized by recurrent occipital headache with typical migrainous phenomena in conjunction with a variety of symptoms referable to a transient dysfunction of the brainstem, the cerebellum and the occipital lobes. Impairment of consciousness is a common feature but is usually too brief to be captured by electroencephalography. Here we report an unusual case of basilar artery migraine with prolonged attacks of impaired consciousness lasting more than two weeks, thus allowing electroencephalographic follow-up. In the acute stage, EEG showed marked generalized slow wave delta activity. After the attack, both the electroencephalographic and clinical findings subsided within the following weeks.

Adult↗
PubMed1989

Beneficial effects of cervical spinal cord stimulation (cSCS) on patients with impaired consciousness: a preliminary report.

Electrical stimulation of the spinal cord can be used for treatment of intractable pain and spasticity. Based on our experimental findings cervical spinal cord stimulation (cSCS) was performed on eight patients with severe brain dysfunction due to traffic accidents, pronounced vasospasm caused by subarachnoid hemorrhage or surgery of huge cerebral tumors (chordoma). After a 1 to 2 month period of stimulation, two patients became conscious and began to speak. It remains unclear whether cSCS induced the restoration of consciousness and improved neurological deficits. Although the successful results might be due to chance, cSCS might have stimulated brain function. This preliminary report shows such excellent results that further studies are warranted.

Adult↗
PubMed1995

Presence of Klùver-Bucy syndrome as a positive prognostic feature for the remission of traumatic prolonged disturbances of consciousness.

After severe brain injury a prolonged disturbance of consciousness may occur, sometimes with transient apallic syndrome (awakening without awareness of self and surroundings). Klùver-Bucy is described in the literature as a typical post-traumatic remission phase, in which the patients show an increase of oral automatisms and/or of sexual drive. The study describes Klùver-Bucy syndrome as a sign associated with favourable prognosis in the outcome of traumatic disturbances of consciousness in survivors of head trauma. Seventy-seven patients who had suffered severe brain injury due to traffic accidents entered into the study. All had experienced a relatively benign clinical course since they recovered full awareness, that is were able to communicate with their relatives. The occurrence of prolonged coma, of apallic syndrome and of Klùver-Bucy syndrome are related to outcome date in regards to the patient's work and family function at a mean of 32 months later. In particular, the duration of the apallic syndrome (duration of unconsciousness) was significantly correlated with the global outcome of the patients (p < 0.001).

Adolescent↗
PubMed1975

Empirical investigations on the reliability and the value for differential diagnosis of 21 clinical symptoms of disturbed states of consciousness.

Two groups of patients in disturbed states of consciousness (DSC's) were compared with three groups of patients in clear states of consciousness (CSC's): demented, schizophrenic, and non-psychotic patients. In each of the groups, 15 patients were evaluated for 21 "objective" symptoms; each patient was evaluated by two psychiatrists. In this way, reliable symptoms were sought out which could discriminate: 1) elderly patients in DSC's from elderly demented but clear patients; and 2) schizophrenic patients from patients in DSC's caused by either withdrawal states after abuse of alcohol or barbiturates, or psychogenic psychoses. Reliable and discriminating symptoms were found. However, different symptoms discriminated when patients in different diagnostic groups were compared. Three kinds of discriminating values of a symptom may be distinguished from one another: 1) only the presence of a symptom is informative; 2) only its absence is informative; 3) both presence and absence of the symptom are informative.

Adolescent↗
PubMed1976

Experienced reality in somatic patients more that 65 years old. A comparative study of disturbed and clear, but demented states of consciousness.

Eight experienced qualities of reality were examined in relation to five sorts of experience in 15 demented patients in clear states of consciousness (the CSC group), and in 15 patients in disturbed states of consciousness (the DSC group). Many more abnormal reality qualities appeared in the DSC than in the CSC group. In the DSC patients the tendency to experience non-existent fantasy items as being real was so much greater than in the CSC patients that it will be of value in differential diagnosis if it is confirmed in other patient materials. In DSC patients, furthermore, positive qualities of sensation were found attached to many experiences of items which were not present in the actual stimulus fiels - even in patients who were not clinically hallucinated. The reliability of the results was controlled by having each patient evaluated by two psychiatrists.

Aged↗
PubMed1990

Atrial natriuretic factor (ANF 103-126) enhances volume- and pressor-induced heart rate response in the conscious rat.

The reduction in blood pressure due to ANF(103-126) fails to elicit reflex cardioacceleration in the conscious rat. To examine baroreflex sensitivity, the effect of ANF(103-126) on the heart period (HP) response to rapid central volume expansion and to alterations in mean arterial pressure (MAP) induced by bolus injections of phenylephrine and sodium nitroprusside was assessed. ANF(103-126) significantly augmented the bradycardic response induced by acute volume expansion from 426 +/- 21 to 391 +/- 23 beats min-1 versus 421 +/- 23 to 405 +/- 24 without ANF(103-126). Baroreflex sensitivity was defined by the ratio of the change in heart period to the maximal change in mean arterial pressure. The dose of ANF(103-126) utilized did not affect basal heart rate or the magnitude of the mean arterial pressure response to phenylephrine but did significantly enhance the nitroprusside-induced decrease in mean arterial pressure. Baroreceptor sensitivity to phenylephrine was significantly increased by ANF(103-126): 0.997 +/- 0.07 (ms mmHg-1) during ANF(103-126) vs 0.613 +/- 0.08 during vehicle. The total duration of the heart rate response to phenylephrine was also prolonged. In contrast, ANF(103-126) did not alter the baroreceptor sensitivity (1.45 +/- 0.3 vs 1.43 +/- 0.2 ms mmHg-1) or duration of heart rate response to nitroprusside. In the conscious rat, ANF(103-126) modifies the heart rate response to changes in mean arterial pressure and acute central volume expansion. This action appears to be dependent on stimulation of cardiac vagal afferents.

Animals↗
PubMed1995

Phosphate excretion during 24 h of hypoxia in conscious rats.

The objective of this study was to investigate renal phosphate excretion during 24 h of hypoxia in conscious rats fed by total parenteral nutrition. Wistar rats weighing 190 g were exposed to hypoxia (inspired oxygen fraction = 0.10) or normoxia (inspired oxygen fraction = 0.21) for 24 h in a normobaric chamber. Renal clearance and hormonal studies were performed. The results showed a greater fractional excretion of phosphate (5.37 +/- 0.07%, P < 0.05) and hypophosphataemia (7.40 +/- 0.12 mg dL-1, P < 0.01) in hypoxic rats (n = 10) than in normoxic rats (n = 13; 3.50 +/- 0.37% and 8.02 +/- 0.16 mg dL-1, respectively). In addition, during hypoxia there was a significant decrease in the excretion of urinary adenosine 3',5'-cyclic monophosphate per glomerular filtrate (2.97 +/- 1.27 nmol dL-1, P < 0.005), a parameter of the renal action of parathyroid hormone, and a stable level of serum parathyroid hormone (10.2 +/- 2.6 ng mL-1) (cf. normoxia: 8.57 +/- 0.70 nmol dL-1 and 8.0 +/- 1.7 ng mL-1, respectively). However, creatinine clearance and the renal adenosine triphosphate level, both of which affect adenosine 3',5'-cyclic monophosphate excretion, were not different between the two groups. These data suggest that exposure of conscious rats to 24 h of hypoxia causes renal hyporesponsiveness to physiological levels of parathyroid hormone, which is manifested as a decrease in adenosine 3',5'-cyclic monophosphate excretion. Phosphaturia is not a direct net effect of hypoxia and secondary hypocapnia on renal phosphate transport, which is known to be regulated by parathyroid hormone through adenosine 3',5'-cyclic monophosphate.

Animals↗
PubMed2001

The conscious cell.

The evolutionary antecedent of the nervous system is "microbial consciousness." In my description of the origin of the eukaryotic cell via bacterial cell merger, the components fused via symbiogenesis are already "conscious" entities. I have reconstructed an aspect of the origin of the neurotubule system by a hypothesis that can be directly tested. The idea is that the system of microtubules that became neurotubules has as its origin once-independent eubacteria of a very specific kind. Nothing, I claim, has ever been lost without a trace in evolution. The remains of the evolutionary process, the sequence that occurred that produced Cajal's neuron and other cells, live today. By study of obscure protists that we take to be extant decendants of steps in the evolution of cells, we reconstruct the past directly from living organisms. Even remnants of "microbial mind" can be inferred from behaviors of thriving microorganisms. All of the eukaryotes, not just lichens or an animal's neurons, are products of symbiogenesis among formerly free-living bacteria, some highly motile. Eukaryotes have evolved by the inheritance of acquired genomes; they have gained all their new features by ingesting and not digesting whole bacterial cells with complete genomes.

Animals↗
PubMed2001

Consciousness and the binding problem.

It is proposed that phenomenal awareness, the ability to be aware of one's sensations and feelings, emerges from the capacity of evolved brains to analyze their own cognitive processes by iterating and reapplying on them-selves the very same cortical operations that they use for the interpretation of signals from the outer world. Search for the neuronal substrate of awareness therefore converges with the search for the cognitive mechanisms through which brains analyze their environment. The hypothesis is put forward that the mammalian brain generates continuously highly dynamic states that, when modulated by input signals, rapidly converge towards points of transient stability that correspond to the respective input constellation. It is proposed that these states are characterized by the dynamic binding of feature-specific cells into functionally coherent cell assemblies which as a whole represent the constellation of features defining a particular perceptual object. Arguments are presented that favor the notion that the cognitive operations supporting awareness consist of an iteration of such dynamic binding processes which then lead to the formation of higher-order assemblies that correspond to the contents of conscious awareness. Experimental data are reviewed relating to the questions of how assemblies are formed and which signatures define the relations among the responses of distributed neurons. It is argued that assemblies self-organize through reciprocal interactions of neurons coupled by reentrant loops and that the signature of relatedness consists of the transient synchronization of the discharges of the respective neurons. Evidence is presented that these synchronization phenomena depend on the same state variables as awareness: Both require for their manifestation activated brain states characterized by desynchronized EEGs. It is concluded that phenomenal awareness is amenable to neurobiological reductionism; but it is also proposed that self-consciousness requires a different explanatory approach because it emerges from the dialogue between different brains and hence has the quality of a cultural construct.

Animals↗
PubMed1988

The relationship between certain blood cations in cows with milk fever and both the state of consciousness and the position of cows when attended.

In one study, a comparison was made of the concentrations and ratios of certain blood cations in 2 groups of cows with milk fever, one showing normal consciousness (n = 8) and the other depressed consciousness (n = 24). There were no significant differences in the mean concentrations of serum total calcium, plasma inorganic phosphorus and potassium, erythrocyte sodium and potassium, the serum calcium/serum magnesium ratio or the plasma sodium/erythrocyte sodium ratio. There were significant differences (all P less than 0.05) in the mean (+/- SD) concentrations of serum magnesium and plasma sodium concentrations, and the plasma sodium/serum magnesium ratio of 0.8 +/- 0.28 vs 1.2 +/- 0.37 mmol/l, 155 +/- 3.0 vs 147 +/- 6.4 mmol/l and 180 +/- 40.1 vs 116 +/- 34.1 for normal vs depressed cows, respectively. In a second study, a comparison was made of the concentrations and ratios of the same blood cations in 3 groups of cows in different positions when attended for milk fever, namely standing (n = 6), sternal recumbency (n = 24) and lateral recumbency (n = 31). There were no significant differences between the mean concentrations or ratios of any of the cations.

Animals↗
PubMedDate not supplied

Hemodynamic effects of calcium gluconate administered to conscious horses.

Calcium gluconate was administered to conscious horses at 3 different rates (0.1, 0.2, and 0.4 mg/kg/min for 15 minutes each). Serum calcium concentrations and parameters of cardiovascular function were evaluated. All 3 calcium administration rates caused marked increases in both ionized and total calcium concentrations, cardiac index, stroke index, and cardiac contractility (dP/dtmax). Mean arterial pressure and right atrial pressure were unchanged; heart rate decreased markedly during calcium administration. Ionized calcium concentration remained between 54% and 57% of total calcium concentration throughout the study. We conclude that calcium gluconate can safely be administered to conscious horses at 0.1 to 0.4 mg/kg/min and that administration will result in improved cardiac function.

Animals↗
PubMed1987

Schizophrenia: a failure to control the contents of consciousness?

Frith (1979) proposed that the 'positive' symptoms of schizophrenia, i.e. hallucinations, delusions, and though disorder, could be accounted for in terms of a defect in the mechanism(s) that controls and limits the contents of consciousness. The present study was designed to test one of the predictions derived from this model; that schizophrenics should fail to inhibit alternative meanings of ambiguous words. As a means of testing this prediction the effects of semantic priming on the 'availability' of subsequent target words to consciousness were assessed, measuring recognition thresholds. The priming conditions employed were expected to either facilitate or inhibit perception of target words in the control groups, normals and depressed patients without psychotic features. A strong priming effect was obtained in the control groups, but was much weaker in the schizophrenic group; this provides some support for the model.

Adult↗
PubMed1976

Adrenal and pancreatic endocrine responses to hypoxia in the conscious calf.

1. Pancreatic and adrenal responses to intense hypoxia have been examined in conscious unrestrained calves 3-5 weeks after birth. 2. The outputs of both cortisol and corticosterone from the right adrenal gland rose steadily in response to hypoxia and this cortical secretory response was accompanied by a pronounced increase in blood flow through the gland. The changes in both steroid output and adrenal blood flow corresponded with those which occur in response to supramaximal doses of corticotrophin in calves of the same age. 3. Neither adrenaline nor noradrenaline were released in significant amounts from the adrenal medulla until the arterial PO2 had fallen below 15 mmHg. Such severe hypoxia caused secretion of catecholamines at rates comparable with those recorded during maximal stimulation of the sympathetic innervation to the gland in anaesthetized calves. The response to intense hypoxia in these conscious calves differed from that which occurs under anaesthesia in that the amount of adrenaline released was invariably greater than that of noradrenaline. 4. Severe hypoxia produced a rapid but transient increase in plasma glucagon concentration, followed by a pronounced rise in plasma glucose concentration in animals with abundant liver glycogen. No change in plasma insulin concentration was observed during hypoxia although it rose subsequently in response to hyperglycaemia. 5. Bilateral section of the splanchnic nerves virtually abolished the release of catecholamines in response to hypoxia but the adrenal cortical and pancreatic responses did not appear to be affected.

Adrenal Glands↗