Neuroscience

Disruptions in sleep/wake cycles, including decreased amplitude of rhythmic behaviors and fragmentation of the sleep episodes, are commonly associated with aging in humans and other mammals. While there are undoubtedly many factors contributing to these changes, a body of literature is emerging, suggesting that an age-related decline in the central circadian clock in the suprachiasmatic nucleus (SCN) may be a key element responsible. To explore age-related changes in the SCN, we have performed in vivo multiunit neural activity (MUA) recordings from the SCN of freely moving young (3-5 months) and middle-aged (13-18 months) mice. Importantly, the amplitude of day-night difference in MUA was significantly reduced in the older mice. We also found that the neural activity rhythms are clearly degraded in the subparaventricular zone, one of the main neural outputs of the SCN. Surprisingly, parallel studies indicate that the molecular clockwork in the SCN as measured by PER2 exhibited only minor deficits at this same age. Thus, the circadian output measured at the level of neural activity rhythms in the SCN is degraded by aging, and this decline occurs before the disruption of key components of the molecular clockwork.

In recent decades, developments in research technologies and therapeutic advances have generated immense public recognition for neuroscience. However, its origins as a field, often linked to partnerships and projects at various brain-focused research centres in the United States during the 1960s, can be traced much further back in time.

In A New Field in Mind Frank Stahnisch documents and analyzes the antecedents of the modern neurosciences as an interdisciplinary field. Although postwar American research centres, such as Francis O. Schmitt's Neuroscience Research Program at MIT, brought the modern field to prominence, Stahnisch reveals the pioneering collaborations in the early brain sciences at centres in Germany, Austria, and Switzerland in the first half of the twentieth century. One of these, Heinrich Obersteiner's institute in Vienna, began its work in the 1880s. Through case studies and collective biographies, Stahnisch investigates the evolving relationships between disciplines - anatomy, neurology, psychiatry, physiology, serology, and neurosurgery - which created new epistemological and social contexts for brain research. He also shows how changing political conditions in Central Europe affected the development of the neurosciences, ultimately leading to the expulsion of many physicians and researchers under the Nazi regime and their migration to North America.

An in-depth and innovative study, A New Field in Mind tracks the emergence and evolution of neuroscientific research from the late nineteenth century to the postwar period.

The minimum frustration principle is a computational approach which states that, in the long timescales of evolution, proteins’ freeenergy decreases more than expected by thermodynamical contraints as their aminoacids assume conformations progressively closer to the lowest energetic state. Here we show that this general principle, borrowed from protein folding dynamics, can be fruitfully applied to nervous function too. Highligting the foremost role of energetic requirements, macromolecular dynamics, and, above all, intertwined timescales in brain activity, the minimum frustration principle elucidates a wide range of mental processes, from sensations to memory retrieval. Brain functions are compared to trajectories which, in long nervous timescales, are attracted towards the lowenergy bottom of funnel-like structures characterized both by robustness and plasticity. We discuss how the principle, as derived explicitly from evolution and selection of a funneling structure from microdyn...

9 Premessa 11 Premessa alla seconda edizione LINGUA PENSIERO CANTO 17 Prima lezione. La lingua e l'informazione 18 § 1. L'essenza e l'indole 23 § 2. Il format della lingua 29 § 3. La prestanza del segno 36 § 4. L'informazione 47 Seconda lezione. La scienza cognitiva e la lingua 48 § 5. Il titolo disciplinare 50 § 6. L'informazione e il senso 51 § 7. La mente e il pensiero 54 § 8. Il pre-linguistico 58 § 9. La naturalizzazione 65 § 10. L'evidenza naturale e il senso comune. La coartazione cibernetica 68 § 11. Il format cognitivista della filosofia. L'occhio storico In copertina: Paul Klee, Traum-Stadt, 1921. © Ibis, Como -Pavia, 2014 www.ibisedizioni.it I edizione: dicembre 2010 Nuova edizione ampliata: settembre 2014 ISBN: 978-88-7164-351-9 Paul Klee, Die Schlangengöttin und ihr Feind, 1940 77 Terza lezione. La verità della lingua e la tentazione 78 § 12. La formatazione e la potenza. Il mercato e la lingua 82 § 13. La mala indole 84 § 14. La verità della lingua 86 § 15. «Dei beni il più tentante». L'insidia (rinvio a Hölderlin) 101 Quarta lezione. Un colpo d'occhio al cammino 101 § 16. L'indole della lingua e il suo format 105 § 17. La lingua madre (coartata) nella scienza cognitiva. L'estrema formatazione 112 § 18. La lingua, l'azienda, il mercato 116 § 19. Excursus. La città smisurata 124 § 20. La lingua come tentazione 127 § 21. «Dei beni il più tentante» (Hölderlin) 124 § 22. Il dono della lingua, l'uomo, la genitura, il bene, l'indolica tentazione (Heidegger) 124 § 23. Conclusione. La fuga delle divergenze e l'enigma della lingua

Localisation of sensory symptoms and signs to specifi c parts of the central and peripheral nervous systems is a signifi cant part of the neurological examination and diagnostic evaluation-the crucial 'where is the lesion?' question. Ever since the fi rst attempts at mapping dermatomes in the late 19th century, neurologists have used dermatomes in their clinical diagnosis of radiculopathy and in determining the level of spinal cord injury. Neurosurgeons and neurophysiologists rely on dermatomes for intraoperative monitoring of The concept of dermatomes came from early attempts to correlate the physiology of sensation with anatomy. There are various defi nitions of dermatomes and several maps in common use. While useful, dermatomes are subject to considerable variation between maps and, indeed, between individuals. Anecdotally, precise dermatome distributions are generally regarded by experienced neurologists with a degree of caution, being viewed as an approximation. In this article, we consider the validity of the dermatome maps and their background, as well as introducing a relatively recent 'evidence based' dermatome map.

"The presentation guides you to discover in a fresh way how TESOL is a partial and integral expression of the Christian path to wholeness by virtue of the process of cultural, linguistic and identity paradigm shifts. What a meta-cognitive model integrating TESOL and Christianity does, is build from the empirical to the realm of the mind, heart and spirit - which is core transformation.  It’s a journey to an unseen and ideal place, much like Norton’s “imagined communities”.  This can be translated, of course, to Abraham’s journey to a heavenly city.  We meet our students there, in no-man’s-land as it were, and this model gives teachers and students a handle on how to move forward.

Coral mortality has increased in recent decades, making coral recruitment more important than ever in sustaining coral reef ecosystems and contributing to their resilience. This review summarizes existing information on ecological factors affecting scleractinian coral recruitment. Successful recruitment requires the survival of coral offspring through sequential life history stages. Larval availability, successful settlement, and post-settlement survival and growth are all necessary for the addition of new coral individuals to a reef and ultimately maintenance or recovery of coral reef ecosystems. As environmental conditions continue to become more hostile to corals on a global scale, further research on fertilization ecology, connectivity, larval condition, positive and negative cues infl uencing substrate selection, and post-settlement ecology will be critical to our ability to manage these diverse ecosystems for recovery. A better understanding of the ecological factors infl uencing coral recruitment is fundamental to coral reef ecology and management.

To figure out whether the main empirical question "Is our brain hardwired to believe in and produce God, or is our brain hardwired to perceive and experience God?" is answered, this paper presents systematic critical review of the positions, arguments and controversies of each side of the neuroscientific-theological debate and puts forward an integral view where the human is seen as a psychosomatic entity consisting of the multiple levels and dimensions of human existence (physical, biological, psychological, and spiritual reality), allowing consciousness/mind/spirit and brain/body/matter to be seen as different sides of the same phenomenon, neither reducible to each other. The emergence of a form of causation distinctive from physics where mental/conscious agency (a) is neither identical with nor reducible to brain processes and (b) does exert "downward" causal influence on brain plasticity and the various levels of brain functioning is discussed. This manuscript also discusses the role of cognitive processes in religious experience and outlines what can neuroscience offer for study of religious experience and what is the significance of this study for neuroscience, clinicians, theology and philosophy. A methodological shift from "explanation" to "description" of religious experience is suggested. This paper contributes to the ongoing discussion between theologians, cognitive psychologists and neuroscientists.

Pain is oen perceived an unpleasant experience that includes sensory and emotional/motivational responses. Accordingly, pain serves as a powerful teaching signal enabling an organism to avoid injury, and is critical to survival. However, maladaptive pain, such as neuropathic or idiopathic pain, serves no survival function. Genomic studies of individuals with congenital insensitivity to pain or paroxysmal pain syndromes considerable increased our understanding of the function of peripheral nociceptors, and especially of the roles of voltage-gated sodium channels and of nerve growth factor (NGF)/TrkA receptors in nociceptive transduction and transmission. Brain imaging studies revealed a "pain matrix, " consisting of cortical and subcortical regions that respond to noxious inputs and can positively or negatively modulate pain through activation of descending pain modulatory systems. Projections from the periaqueductal grey (PAG) and the rostroventromedial medulla (RVM) to the trigeminal and spinal dorsal horns can inhibit or promote further nociceptive inputs. e "pain matrix" can explain such varied phenomena as stress-induced analgesia, placebo effect and the role of expectation on pain perception. Disruptions in these systems may account for the existence idiopathic pan states such as bromyalgia. Increased understanding of pain modulatory systems will lead to development of more effective therapeutics for chronic pain. Scienti ca ACC SI SII INS Thalamus AMY PAG A7 PB A6 RVM DRG Peripheral afferent fiber (nociceptor) (a) A6 ACC SI SII INS Thalamus AMY PAG A7 PB RVM DRG Peripheral afferent fiber (nociceptor) (b)

The hypothesis to detect a sequence of events by analyzing the EEG activity of two human partners spatially separated and connected only mentally, was explored sending to a member of the couple a sequence of silence-signal events and analyzing the EEG activity of the second member of the couple. By using a special classification algorithm and five couples of participants characterized by a long friendship and a capacity in maintaining a focused mental concentration, we observed an overall percentage of correct coincidences of 78%, ranging from one-hundred percent for the first two segments, to approximately forty-three percent of the last two. The percentages of coincidences of the first five segments of the protocol were above eighty percent.
Furthermore a robust statistically significant correlation was observed in the alpha band in twelve out fifteen pairs of recordings.
The observed results seem supporting the possibility to connect two brains at distance excluding conventional means, paving the way to devise a sort of mental telecommunication at distance.

Previously in (Vimal, 2010a), we argued that: (i) it is necessary to link experience and function aspect of consciousness with the related structure or neural correlate(s) of consciousness (NCC); and (ii) nonconscious experiences are equivalent to relevant proto-experiences at various levels because both are precursors of conscious subjective experiences aspect of consciousness. Here, in terms of dual-aspect dual-mode PE-SE (proto-experience/subjective experience) framework , we argue as follows: (I) Non-experiential consciousness is a part of functional aspect of consciousness and consciousness is more fundamental than experience because experiences and functions are two aspects of consciousness. I (II) Therefore, one could argue for the continuum of consciousness, experience, and function. (III) The origin of individual consciousness could be a ‗universal background of awareness' that is equivalent to virtual reservoir (where potential SEs are stored in superposed form, and a specific SE is selected via matching process) in the PE-SE framework. The interaction between zombies is relational but it would not lead to an individual consciousness in each zombie. 1 The origin of intersubjective consciousness is the interaction between individual consciousnesses, i.e., interaction between ‗I', ‗you', and ‗she/he/it', i.e., interactions between minds/brains and their environments. (IV) A specific SE is selected during matching process and conscious experience constructs the perception or SE of external objects. (V) The dual-aspect dual-mode PE-SE framework is consistent with classical doubleaspectism in the sense of inseparability of mental and physical aspect, whereas it is consistent with double-perspectivism in the sense that the mental aspect is known via first person perspective and the physical aspect is known via third person perspective. (VI) Our conventional reality is subject inclusive or mind dependent reality (MDR), whereas the subject exclusive or mind independent reality (MIR) remains always unknown even in so called samadhi state of mind that claims to have direct perception (or consciousness as such), which may or may not be close to MIR. 2 (VII) The hard problems are Types 1-3

The concept that the gut microbiota serves as a virtual endocrine organ arises from a number of important observations. Evidence for a direct role arises from its metabolic capacity to produce and regulate multiple compounds that reach the circulation and act to influence the function of distal organs and systems. For example, metabolism of carbohydrates results in the production of short chain fatty acids (SCFAs), such as butyrate and propionate, which provide an important source of nutrients as well as regulatory control of the host digestive system. This influence over host metabolism is also seen in the ability of the prebiotic inulin is to influence production of relevant hormones such as glucagon like peptide-1 (GLP-1), peptide YY (PYY), ghrelin and leptin. Moreover, the probiotic L. rhamnosus PL60, which produces conjugated linoleic acid, has been shown to reduce body weight gain and white adipose tissue without effects on food intake. Manipulating the microbial composition of the gastrointestinal tract modulates plasma concentrations of tryptophan, an essential amino acid and precursor to serotonin, a key neurotransmitter within both the enteric and central nervous systems. Indirectly and through as yet unknown mechanisms, the gut microbiota exerts control over the hypothalamic-pituitary-adrenal axis (HPA). This is clear from studies on animals raised in a germ-free environment, who show exaggerated responses to psychological stress, which normalises following monocolonisation by certain bacterial species including B. infantis. It is tempting to speculate that therapeutic targeting of the gut microbiota may be useful in treating stress-related disorders and metabolic diseases.

GH O ne out of three adults is a collector, someone who acquires and treasures objects of value. The other two-thirds of the population either live with a collector or know several of them. Despite this large, interested audience, the question of exactly why collectors collect remains unanswered.

A growing number of publications have been exploring the possible effects of mindfulness-based interventions on teachers' well-being and their professional lives. Notwithstanding promising results in this domain, this paper identifies some difficulties involved in introducing teachers to mindfulness and proposes that there may be a need to develop alternative routes by which to expose more teachers to experiences of mindfulness. We report on a mixed methods study of a 5-week teacher learning program implemented in an Israeli middle school with 30 teachers, 28 of which were females, with an age range of 29-55. The program was designed to invite teachers into initial experiences with mindfulness without formally engaging in mindfulness practice but rather based on studying education-relevant brain theory through a contemplative pedagogical approach. Outcomes were analyzed quantitatively by comparing collaborative concept maps created by the participants before and after undergoing in the program, and qualitatively by analyzing themes extracted from the participants’ discourse. Findings show that the program: (a) mobilized teachers from fixed to growth mindsets in regards to their role as educators as reflected in a significant increase in teachers’ beliefs that basic brain abilities are malleable (as extracted from the concept maps, p=0.004), (b) offered them initial experiences of mindfulness, and (c) possibly opened them to consider more direct approaches to mindfulness practice that are offered in mindfulness-based interventions.

Virtual reality (VR) head-mounted displays (HMD) appear to be effective research tools,
which may address the problem of ecological validity in neuropsychological testing.
However, their widespread implementation is hindered by VR induced symptoms
and effects (VRISE) and the lack of skills in VR software development. This study
offers guidelines for the development of VR software in cognitive neuroscience and
neuropsychology, by describing and discussing the stages of the development of Virtual
Reality Everyday Assessment Lab (VR-EAL), the first neuropsychological battery in
immersive VR. Techniques for evaluating cognitive functions within a realistic storyline
are discussed. The utility of various assets in Unity, software development kits, and other
software are described so that cognitive scientists can overcome challenges pertinent
to VRISE and the quality of the VR software. In addition, this pilot study attempts to
evaluate VR-EAL in accordance with the necessary criteria for VR software for research
purposes. The VR neuroscience questionnaire (VRNQ; Kourtesis et al., 2019b) was
implemented to appraise the quality of the three versions of VR-EAL in terms of user
experience, game mechanics, in-game assistance, and VRISE. Twenty-five participants
aged between 20 and 45 years with 12–16 years of full-time education evaluated various
versions of VR-EAL. The final version of VR-EAL achieved high scores in every sub-score
of the VRNQ and exceeded its parsimonious cut-offs. It also appeared to have better
in-game assistance and game mechanics, while its improved graphics substantially increased the quality of the user experience and almost eradicated VRISE. The results
substantially support the feasibility of the development of effective VR research and
clinical software without the presence of VRISE during a 60-min VR session.

As hundreds of so-called "psychotherapies" have been foisted onto the public, all claiming to treat "mental illness," newer understandings of how the human brain actually works and the processes which drive the formations of mentation that we refer to as "the mind," demand a reassessment of what exactly we are referring to by the term "mental illness" and what kinds of intervention would be feasible in both the prevention of and recovery from cognitive and behavioral disorder. A fundamental process in the formation of an individual's mentation is the associations of experience. These associations not only account for constructive behavior, but can also lead to deleterious or negative behavior, suggesting that some associations are negative and therefore the negative behavior can be remolded through contrasting positive associations; however, to understand what this really means and how it works, we must start at the beginning and define what exactly is this negative behavior that we refer to by the term "mental illness." One of the most important axioms of life so simply but profoundly phrased by Oscar Wilde, is that "the truth is rarely pure and NEVER simple" (emphasis mine). Nothing can ever be explained by simple sound bites – oversimplification is just another word for misrepresentation – so to understand, we must truly engage the subject, and to engage the subject, we must first and foremost clearly define what it is that we are seeking to understand. In this case, it demands that we understand what exactly is mental illness.

External ventricular drains (EVDs) are commonly used to facilitate removal of cerebrospinal fluid in patients with neurologic dysfunction. Despite a high risk for infection (upward of 45%), many hospitals lack strict protocols for EVD placement and maintenance. In addition, EVD infections are typically not tracked with the same diligence as central-line catheter infections, because there are no widely accepted standards for routine management of EVDs. The purpose of this review is to provide a guide for the development of a standardized, best practice EVD protocol for catheter insertion, care, and maintenance to reduce ventriculostomy-related infections. A secondary goal of this review is to provide support for the future development of guidelines for the consistent tracking of EVD insertion and maintenance practices. At an academic medical center, an interdisciplinary team of nurses, advanced practice nurses, and neurointensivists reviewed recent medical and nursing literature as well as research-based institutional protocols on EVD insertion and maintenance from the United States and abroad to determine global best practices. The goal of this literature review was to identify key areas of focus in EVD insertion and maintenance as well as to identify recent studies that have shown success in managing EVDs with low rates of infection. The following terms were used in this search: EVD, externalized ventricular drains, EVD infections, EVD insertion, EVD Care and Maintenance, Nursing and EVDS. The following databases were utilized by each member of the interdisciplinary team to establish a state of the science on EVD management: American Association of Neurosurgical Surgeons, CINAHL, Cochrane, National Guidelines Clearinghouse, and PubMed. The following common EVD themes were identified: preinsertion hair removal and skin preparation, aseptic technique, catheter selection, monitoring of EVD insertion technique using a ''bundle'' approach, postinsertion dressing type and frequency of dressing changes, techniques for maintenance and cerebrospinal fluid sampling, duration of catheter placement, staff education/competence, and surveillance.

NB: Out of Stock. The 2nd edition, entitled "Neurology: Self-Assessment for MRCP(UK) Neurology SCE", was published in 2023 and is found here: https://www.academia.edu/96771620/Neurology_Self_Assessment_for_MRCP_UK_Neurology_SCE
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You will find 792 questions of different formats, distributed into 3 chapters. The 215 multiple choice questions of chapter one will surf you onto a rapid review of information to consolidate your background knowledge of neuro-anatomy, neuro-physiology, neuro-pharmacology, neuro-pathology,…etc. In addition, testing the clinical aspects of various diseases is also included. Chapter two will self-assess you in terms of how to make a provisional diagnosis, what features refute or confirm your preliminary diagnosis, how to investigate, what to do next, the best treatment option, and the prognosis of various diseases. The photographic materials are found in chapter three. You will encounter various neurological complications/manifestations/signs of system diseases as well. Brain CT scan, MRI, MRV, and EEG images,…etc of common diseases will test your ability to interpret/read/analyze their diagnosis and management. About 490 pages, full-color, on white.

While writing our book Neuroleadership which explored the field of neuroleadership (combining neuroscience with leadership) we came across the work of Klaus Grawe. His work in neuropsychotherapy and the Consistency Theory he proposed we found to be particularly interesting and saw it as model that can be applied in all systems within which human beings operate. Since writing Neuroleadership and applying the models we proposed in the business world we have come to the conclusion that indeed this is a very relevant but also practical model that can be applied to leadership scenarios. Moreover, and understandably given its roots in neuropsychotherapy, this we see can be applied with great impact in coaching contexts. We hence propose a model of basic human needs as an integrated coaching framework (SCOAP Coach Theory).

A chronic continuous or intermittent gastrointestinal tract dysfunction, the irritable bowel syndrome (IBS), appears to be due to dysregulation of brain-gut-microbiota communication. Furthermore, the "microbiota" greatly impacts the bi-directional brain-gut axis communication. This article describes IBS in relation to similar diseases, presents the background to osteopathy, and proposes osteopathic manipulative treatment (OMT) to manage IBS. In IBS, OMT focuses on the nervous and circulatory systems, spine, viscera, and thoracic and pelvic diaphragms in order to restore homeostatic balance, normalize autonomic activity in the intestine, promote lymphatic flow, and address somatic dysfunction. Lymphatic and venous congestion are treated by the lymphatic pump techniques and stimulation of Chapman's reflex points. A simple treatment plan designed to lessen chronic pain and inflammation in IBS is presented based on current evidence-based literature. Since food itself, food allergies, and intolerance could contribute to symptom onset or even cause IBS, this article also provides dietary modifications to consider for patients.

This study investigated the effect of methylphenidate (Ritalin) on the selective attention of hyperactive children designated as favorable or adverse responders to stimulant medication. Using a type II incidental learning paradigm, it was found that children in the drug condition recalled more central and less incidental stimuli than those children in the placebo condition. While no differential effects on recall were found for responder type, methylphenidate did affect the
spontaneous overt labeling of central stimuli by the favorable responder group. Results were interpreted in terms of the role of methylphenidate in narrowing the focus of attention. Implications for the classification of hyperactive children
as favorable and adverse responders were also discussed.

Nella stanza le donne vanno e vengono parlando di Michelangelo t.s. Eliot di cosa parliamo quando parliamo di michelangelo in anni recenti Michelangelo, come molti altri artisti della modernità (tra tutti, leonardo e Caravaggio), è stato cannibalizzato dalla macchina commerciale che ruota attorno al patrimonio artistico italiano il quale, invece di essere «tutelato», come da Costituzione, viene sfruttato da un marketing spietato. la mistificazione commerciale di Michelangelo, agevolata dalla predilezione della cultura pop per le citazioni fuori contesto, inizia dalla vendita sterminata di gadget di ogni tipo con particolari riferibili allo scultore (dal vestiario agli oggetti per la casa, ai calendari osé con ingrandimenti delle parti anatomiche delle statue, ecc.), ma prosegue sicuramente nell'uso pubblicitario o propagandistico delle opere dell'artista. Esempi di questa commercializzazione possono essere alcune oscure vicende di attribuzione o restauri pretestuosi eseguiti esclusivamente per creare eventi mediatici attorno ad alcuni isolati oggetti-simbolo. Ma, per parafrasare un famoso titolo, di cosa parliamo quando parliamo di Michelangelo? Che cos'è ancora lui per noi?

R not only in their physical attributes and reproductive function but also in many other characteristics, including the way they solve intellectual problems. For the past few decades, it has been ideologically fashionable to insist that these behavioral differences are minimal and are the consequence of variations in experience during development before and after adolescence. Evidence accumulated more recently, however, suggests that the effects of sex hormones on brain organization occur so early in life that from the start the environment is acting on differently wired brains in boys and girls. Such effects make evaluating the role of experience, independent of physiological predisposition, a difficult if not dubious task. The biological bases of sex differences in brain and behavior have become much better known through increasing numbers of behavioral, neurological and endocrinological studies.

Ritmo circadiano: el reloj maestro. Alteraciones que comprometen el estado de sueño y vigilia en el área de la salud Circadian rhythm: the master clock. Alterations involving the state of sleep and wakefulness in the area of healt. Resumen El sueño es un fenómeno periódico activo regular que se adapta a las variaciones biológicas del tiempo mediante ritmos biológicos como los circadianos, infradianos y ultradianos; el ritmo circadiano es descrito como un ciclo cercano a 24 horas, que permite reconocer los fenómenos de sueño-vigilia y su acción homeostática , en los procesos sistémicos de todo ser vivo. El sistema circadiano está compuesto por fotorreceptores, marcapasos y vías eferentes que permiten un funcionamiento regular del estado sueño y vigilia. Desde tiempos arcaicos el hombre ha organizado sus actividades apoyándose en fases de luz y oscuridad, por tal razón ha sido objeto de investigación desde aspectos moleculares, fisiológicos y patológicos. Se destaca la acción fisiológica de núcleos cerebrales, receptores de membrana y hormonas que cumplen un papel fundamental en el ciclo circadiano. En el personal de la salud se resaltan alteraciones en el ritmo biológico de sueño/vigilia que están involucrados con jornadas nocturnas y situaciones de estrés; por tanto, ciertos estudios de investigación descriptiva arrojaron cambios en el reloj biológico, lo cual generó una serie de variables en el aspecto físico, ergonómico y sicosocial. Abstract The sleep is a regular active periodic phenomenon that adapts itself to the biological changes of the time by means of biological rhythms as the circadian, infradiano and ultradian; the circadian rhythm is described as a cycle near to 24 hours, which allows

We tested the hypothesis that the phosphatidylinositol-3 kinase (PI3K/Akt) pathway mediates some of the neuroprotective effects of progesterone (PROG) after ischemic stroke. We examined whether PROG acting through the PI3K/Akt pathway could affect the expression of vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF). Rats underwent permanent focal cerebral ischemia (pMCAO) by electro-coagulation and received intraperitoneal injections of PROG (8mg/kg) or vehicle at 1h post-occlusion and subcutaneous injections at 6, 24, and 48h. PAkt/Akt levels, apoptosis and apoptosis-related proteins (pBAD, BAD, caspase-3, and cleaved caspase-3) were analyzed by TUNEL assays, Western blotting and immunohistochemistry at 24h post-pMCAO. VEGF and BDNF were analyzed at 24, 72h and 14 days post-pMCAO with Western blots. Following pMCAO, PROG treatment significantly (p<0.05) reduced ischemic lesion size and edema. Treatment with PROG significantly (p<0.05) decreased VEGF at 24 and 72h but increased VEGF expression 14d after injury. The treatment also increased BDNF, and attenuated apoptosis by increasing Akt phosphorylation compared to vehicle-alone. The selective PI3K inhibitor Wortmannin compromised PROG-induced neuroprotective effects and reduced the elevation of pAkt levels in the ischemic penumbra. Our findings lead us to suggest that the PI3K/ Akt pathway can play a role in mediating the neuroprotective effects of PROG after stroke by altering the expression of trophic factors in the brain.