A unifying theory of general anesthetic-induced unconsciousness must explain the common mechanism through which various anesthetic agents produce unconsciousness. Functional-brain-imaging data obtained from 11 volunteers during general anesthesia showed specific suppression of regional thalamic and midbrain reticular formation activity across two different commonly used volatile agents. These findings are discussed in relation to findings from sleep neurophysiology and the implications of this work for consciousness research. It is hypothesized that the essential common neurophysiologic mechanism underlying anesthetic-induced unconsciousness is, as with (...) sleep-induced unconsciousness, a hyperpolarization block of thalamocortical neurons. A model of anesthetic-induced unconsciousness is introduced to explain how the plethora of effects anesthetics have on cellular functioning ultimately all converge on a single neuroanatomic/neurophysiologic system, thus providing for a unitary physiologic theory of narcosis related to consciousness. (shrink)

Evil should be characterised as a specific constellation, which results from destructive connections between individual activities and systemic influences. The article shows some important aspects of the structure of evil and prefers the terms of wickedness and obscene coincidences to describe its own character. Therefore, also the division between rationality and affectivity appears as inadequate, because evil has on the one side an intrinsic attractiveness for individuals and is on the other side in modern societies more and more a product (...) of a rationality, which is free from passion. Especially the emotional impoverishment is responsible for the increase of evil, which is demonstrated by two examples. Based on Paul Ricoeur, the evolution of malum can be developed by a short analyse of the relationship between Ethics and Emotions. (shrink)

In this commentary we discuss the possibility of subcortical consciousness and its implications for fetal anesthesia and analgesia. We review the neural development of structural and functional elements that may participate in conscious representation, with a particular focus on the experience of pain. (Published Online May 1 2007).

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. (shrink)

According to the mental models theory, reasoning performance is primarily influenced by the number of models of a problem that can be constructed. This study investigates whether the content of the model may also influence performance. Linear reasoning problems were devised that either described a believable (script-consistent) or an unbelievable (script-inconsistent) order of actions. The results of two experiments showed that conclusions were inferred more slowly and less accurately on the basis of an unbelievable model than on a believable one. (...) Experiment 2 revealed that script knowledge facilitated as well as impeded reasoning performance. Conclusion evaluation was faster and more accurately for script-consistent problems than for neutral problems, whereas model construction and conclusion evaluation occurred respectively more slowly and less accurately for script-inconsistent problems than for neutral problems. These results show that the content of the model is a noteworthy factor influencing reasoning performance. (shrink)

Anesthetic gas molecules are recognized to act by van der Waals (London dispersion) forces in hydrophobic pockets of select brain proteins to ablate consciousness. Enigmatic features of consciousness have defied conventional neurophysiological exp lanations and prompted suggestions for supplemental occurrence of macroscopic quantum coherent states and quantum computation in the brain. Are these feasible? During conscious (non-anesthetic) conditions, endogenous Van der Waals London dispersion forces occur among non-polar amino acid groups in hydrophobic pockets of neural proteins and help regulate their (...) conformation/function. London forces are weak instantaneous couplings between pairs of electron induced dipoles (e.g. between adjacent non-polar amino acid groups), and are quantum mechanical effects capable of supporting quantum superposition/computation and macroscopic quantum coherence. Quantum effects mediated by endogenous London forces in hydrophobic pockets of select neural proteins may be necessary for consciousness. The mechanism of anesthetics may be to inhibit (by exogenous London forces) the necessary quantum states. (shrink)

feelings (brainstem, limbic system). The best scientific synchrony and consciousness.21,27 Anesthesiology, V 105, No 2, Aug 2006.

Photons are intrinsically quantum objects and natural long-distance carriers of information in both classical and quantum communications1. Since brain functions involve information and many experiments have shown that quantum entanglement is physically real, we have contemplated from the perspective of our recent hypothesis2 on the possibility of entangling the quantum entities inside the brain with those in an external anaesthetic sample and carried out experiments toward that end. Here we report that applying magnetic pulses to the brain when a general (...) anaesthetic sample was placed in between caused the brain to feel the effect of said anaesthetic for several hours after the treatment as if the test subject had actually inhaled the same. The said effect is consistently reproducible on all four subjects tested. We further found that drinking water exposed to magnetic pulses, laser light, microwave or even flashlight when an anaesthetic sample was placed in between also causes consistently reproducible brain effects in various degrees. We have in addition tested several medications including morphine and obtained consistently reproducible results. Further, through additional experiments we have verified that the said brain effect is the consequence of quantum entanglement between quantum entities inside the brain and those of the chemical substance under study induced by the photons of the magnetic pulses or applied lights. We suggest that the said quantum entities inside the brain are nuclear and/or electron spins and discuss the profound implications of these results. (shrink)

Continuous recordings of brain electrical activity were obtained from a group of 176 patients throughout surgical procedures using general anesthesia. Artifact-free data from the 19 electrodes of the International 10/20 System were subjected to quantitative analysis of the electroencephalogram (QEEG). Induction was variously accomplished with etomidate, propofol or thiopental. Anesthesia was maintained throughout the procedures by isoflurane, desflurane or sevoflurane (N = 68), total intravenous anesthesia using propofol (N = 49), or nitrous oxide plus narcotics (N = 59). A set (...) of QEEG measures were found which reversibly displayed high heterogeneity of variance between four states as follows: (1) during induction; (2) just after loss of consciousness (LOC); (3) just before return of consciousness (ROC); (4) just after ROC. Homogeneity of variance across all agents within states was found. Topographic statistical probability images were compared between states. At LOC, power increased in all frequency bands in the power spectrum with the exception of a decrease in gamma activity, and there was a marked anteriorization of power. Additionally, a significant change occurred in hemispheric relationships, with prefrontal and frontal regions of each hemisphere becoming more closely coupled, and anterior and posterior regions on each hemisphere, as well as homologous regions between the two hemispheres, uncoupling. All of these changes reversed upon ROC. Variable resolution electromagnetic tomography (VARETA) was performed to localize salient features of power anteriorization in three dimensions. A common set of neuroanatomical regions appeared to be the locus of the most probable generators of the observed EEG changes. (shrink)

This book brings together an international group of neuroscientists and philosophers who are investigating how the content of subjective experience is...

CHAPTER 1 Neurotransmitter networks Elaine Perry and Allan Young i. Introduction This first chapter sets the scene for subsequent exploration of potential ...

Empirical work is reviewed which correlates the presence or absence of various parts of the auditory evoked potential with the disappearance and reemergence of auditory sensation during induction of and recovery from anesthesia. As a result, the hypothesis is generated that the electrophysiological correlate of auditory sensation is whatever neural activity generates the middle latency waves of the auditory evoked potential. This activity occurs from 20 to 80 ms poststimulus in the primary and secondary areas of the auditory cortex. Evidence (...) is presented suggesting that earlier or later waves in the auditory evoked potential do not covary with auditory sensation (as opposed to auditory perception) and it is therefore suggested that they are possibly not the electrophysiological correlates of sensation. (shrink)

The result of the second Appalachian conference on neurodynamics, this volume focuses on the problem of "order," its origins, evolution, and future.

This paper presents research regarding the monitoring of the brain and the adequacy of anesthesia during surgery. Particular variables are derived from EEG and ECG signals and are correlated to anesthetic gas (sevoflurane) concentration, in pediatric anesthesia. The methods used for parameter extraction are based on change detection theory and time-frequency representation. Preliminary results show that the expired anesthetic gas concentration modulates both the heart rate variability and the duration of the burst suppression. Monitors of the central nervous system and (...) autonomic nervous system activities can be expected to be based on these variables. (shrink)

While working to build his aesthetic theory from the qualities of normal, healthy experience, John Dewey diagnoses a rarely recognized experiential ailment -- what might be called the anesthetic malady. This illness generally results when experience is deprived of meaning due to the poverty of the predominant forms of activity available in one's environment. In Dewey's theory of aesthetic experience lies an easily overlooked social/political approach that predates, by almost half a century, recent social theoretical concerns in phenomenology and everyday (...) aesthetics. Dewey takes notice of experience and prompts inquiry into sometimes obviously important, but often dismissed as irrelevant and mundane, paths. (shrink)