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Physiological Explanations (physiological + explanation)
Selected AbstractsA PHYSIOLOGICAL EXPLANATION FOR AN UNEXPECTED BENEFIT OF CAROTID ENDARTERECTOMYJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2007Emre Noteroglu MD No abstract is available for this article. [source] Alcohol in Moderation, Cardioprotection, and Neuroprotection: Epidemiological Considerations and Mechanistic StudiesALCOHOLISM, Issue 2 2009Michael A. Collins In contrast to many years of important research and clinical attention to the pathological effects of alcohol (ethanol) abuse, the past several decades have seen the publication of a number of peer-reviewed studies indicating the beneficial effects of light-moderate, nonbinge consumption of varied alcoholic beverages, as well as experimental demonstrations that moderate alcohol exposure can initiate typically cytoprotective mechanisms. A considerable body of epidemiology associates moderate alcohol consumption with significantly reduced risks of coronary heart disease and, albeit currently a less robust relationship, cerebrovascular (ischemic) stroke. Experimental studies with experimental rodent models and cultures (cardiac myocytes, endothelial cells) indicate that moderate alcohol exposure can promote anti-inflammatory processes involving adenosine receptors, protein kinase C (PKC), nitric oxide synthase, heat shock proteins, and others which could underlie cardioprotection. Also, brain functional comparisons between older moderate alcohol consumers and nondrinkers have received more recent epidemiological study. In over half of nearly 45 reports since the early 1990s, significantly reduced risks of cognitive loss or dementia in moderate, nonbinge consumers of alcohol (wine, beer, liquor) have been observed, whereas increased risk has been seen only in a few studies. Physiological explanations for the apparent CNS benefits of moderate consumption have invoked alcohol's cardiovascular and/or hematological effects, but there is also experimental evidence that moderate alcohol levels can exert direct "neuroprotective" actions,pertinent are several studies in vivo and rat brain organotypic cultures, in which antecedent or preconditioning exposure to moderate alcohol neuroprotects against ischemia, endotoxin, ,-amyloid, a toxic protein intimately associated with Alzheimer's, or gp120, the neuroinflammatory HIV-1 envelope protein. The alcohol-dependent neuroprotected state appears linked to activation of signal transduction processes potentially involving reactive oxygen species, several key protein kinases, and increased heat shock proteins. Thus to a certain extent, moderate alcohol exposure appears to trigger analogous mild stress-associated, anti-inflammatory mechanisms in the heart, vasculature, and brain that tend to promote cellular survival pathways. [source] "Automatism" and the emergence of dynamic psychiatryJOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES, Issue 1 2003Adam Crabtree FacultyArticle first published online: 21 JAN 200 This article is about the clash of two explanatory paradigms, each attempting to account for the same data of human experience. In the first half of the nineteenth century, physiologists investigated reflex actions and applied a recently coined word, "automatism," to describe actions which, although seeming to arise from higher centers, actually result from automatic reaction to sensory stimuli. Experiments with spinal reflexes led to the investigation of the reflex action of the brain or "cerebral automatisms." Reflex actions of this kind were used to explain everything from acting compulsively to composing symphonies. Physiological explanations of phenomena of this kind seemed insufficient to some and, in the 1880s, Frederic Myers and Pierre Janet developed psychological frameworks for understanding these phenomena, positing hidden centers of intelligence at work in the individual, outside ordinary awareness, which produce what came to be called "psychological automatisms." Their attempts to unify this psychological framework with the existing physiological one failed. Nevertheless, their work played a crucial role in paving the way for what Ellenberger called dynamic psychiatry, which accepts the reality of an unconscious dynamic of the psyche. © 2003 Wiley Periodicals, Inc. [source] Functional magnetic resonance imaging of the human brain and spinal cord by means of signal enhancement by extravascular protonsCONCEPTS IN MAGNETIC RESONANCE, Issue 1 2003P.W. Stroman Abstract A review of functional magnetic resonance imaging (fMRI) signal changes in spin,echo image data is presented. Spin,echo fMRI data from the human brain and spinal cord show a consistent departure from that expected with blood oxygen level dependent (BOLD) contrast. Studies to investigate this finding demonstrate fMRI signal changes of 2.5% in the spinal cord and 0.7% in the brain at 1.5 T, which is extrapolated to an echo time of zero. Consistent evidence of a non-BOLD contrast mechanism arising from a proton-density change at sites of neuronal activation is demonstrated. A mathematical model and physiological explanation for signal enhancement by extravascular protons is also presented. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 16A: 28,34, 2003 [source] Physiological Linguistics, and Some Implications Regarding Disciplinary Autonomy and UnificationMIND & LANGUAGE, Issue 1 2007SAMUEL D. EPSTEIN At least current irreducibility of biology, including biolinguistics, stems in at least some cases from the very nature of what I will claim is physiological, or inter-organ/inter-component, macro-levels of explanation which play a new and central explanatory role in Chomsky's inter-componential (interface-based) explanation of certain (anatomical) properties of the syntactic component of Universal Grammar. Under this new mode of explanation, certain physiological functions of cognitive mental organs are hypothesized, in an attempt to explain aspects of their internal anatomy. Thus, the internal anatomy of the syntactic component exhibits features that enable it to effectively interface with (i.e. function in a coordinated fashion with) other ,adjacent' organs, such as the Conceptual-Intensional (C-I) (,meaning') system and the Sensory- Motor (SM) (,sound') system. These two interface systems take as their inputs the assembled outputs of the syntactic component and, as a result of the very syntactic structure imposed by the syntax (as opposed to countless imaginable alternatives) are then able to assign their (linearized) sound and (compositional) meaning interpretations. If this is an accurate characterization, Chomsky's long-standing postulation of mental organs, and I will argue, the advancement of new hypotheses concerning physiological inter-organ functions, has attained in current biolinguistic Minimalist method a significant unification with foundational aspects of physiological explanation in other areas of biology. [source] Endurance exercise performance: the physiology of championsTHE JOURNAL OF PHYSIOLOGY, Issue 1 2008Michael J. Joyner Efforts to understand human physiology through the study of champion athletes and record performances have been ongoing for about a century. For endurance sports three main factors , maximal oxygen consumption , the so-called ,lactate threshold' and efficiency (i.e. the oxygen cost to generate a give running speed or cycling power output) , appear to play key roles in endurance performance. and lactate threshold interact to determine the ,performance , which is the oxygen consumption that can be sustained for a given period of time. Efficiency interacts with the performance to establish the speed or power that can be generated at this oxygen consumption. This review focuses on what is currently known about how these factors interact, their utility as predictors of elite performance, and areas where there is relatively less information to guide current thinking. In this context, definitive ideas about the physiological determinants of running and cycling efficiency is relatively lacking in comparison with and the lactate threshold, and there is surprisingly limited and clear information about the genetic factors that might pre-dispose for elite performance. It should also be cautioned that complex motivational and sociological factors also play important roles in who does or does not become a champion and these factors go far beyond simple physiological explanations. Therefore, the performance of elite athletes is likely to defy the types of easy explanations sought by scientific reductionism and remain an important puzzle for those interested in physiological integration well into the future. [source] Burning mouth syndrome and psychological disordersAUSTRALIAN DENTAL JOURNAL, Issue 2 2009LM Abetz Abstract Burning mouth syndrome (BMS) is an oral dysaesthesia that causes chronic orofacial pain in the absence of a detectable organic cause. The aetiology of BMS is complex and multifactorial, and has been associated in the literature with menopause, trigger events and even genetic polymorphisms. Other studies have found evidence for mechanisms such as central and peripheral nervous system changes, with clinical and laboratory investigations supporting a neuropathologic cause. These physiological explanations notwithstanding, there is still much evidence that BMS aetiology has at least some psychological elements. Somatoform pain disorder has been suggested as a mechanism and factors such as personality, stress, anxiety, depression and other psychological, psychosocial and even psychiatric disorders play a demonstrable role in BMS aetiology and symptomatology. In order to treat BMS patients, both physiological and psychological factors must be managed, but patient acceptance of possible components of psychological disease basis is a major hurdle. Clinical signs of patient stress, anxiety or depression are a useful reinforcement of clinical discussions. The current paper proposes a number of clinical signs that may be useful for both clinical assessment and subsequent patient discussions by providing visible supportive evidence of the diagnosis. [source] | ||||||||||