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Effects of intracisternal administration of cannabidiol on the cardiovascular and behavioral responses to acute restraint stress

GRANJEIRO, Erica M.; GOMES, Felipe V.; GUIMARAES, Francisco S.; CORREA, Fernando M. A.; RESSTEL, Leonardo B. M.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.15%
Systemic administration of cannabidiol (CBD), a non-psychotomimetic compound from Cannabis sativa, attenuates the cardiovascular and behavioral responses to restraint stress. Although the brain structures related to CBD effects are not entirely known, they could involve brainstem structures responsible for cardiovascular control. Therefore, to investigate this possibility the present study verified the effects of CBD (15.30 and 60 nmol) injected into the cisterna magna on the autonomic and behavioral changes induced by acute restraint stress. During exposure to restraint stress (1 h) there was a significant increase in mean arterial pressure (MAP) and heart rate (HR). Also, 24 h later the animals showed a decreased percentage of entries onto the open arms of the elevated plus-maze. These effects were attenuated by CBD (30 nmol). The drug had no effect on MAP and HR baseline values. These results indicate that intracisternal administration of CBD can attenuate autonomic responses to stress. However, since CBD decreased the anxiogenic consequences of restraint stress, it is possible that the drug is also acting on forebrain structures. (C) 2011 Elsevier Inc. All rights reserved.; FAPESP[2009/08647-8]; FAPESP[2010/17343-0]; FAPESP[2009/03187-9]; FAPESP[2007/03685-3]; CNPq[501323/2010-4]; CNPq[305996/2008-8]

Conspecific and heterospecific alarm substance induces behavioral responses in piau fish Leporinus piau

BARBOSA JUNIOR, Augusto; MAGALHAES, Elisangela Jaqueline; HOFFMANN, Anette; IDE, Liliam Midori
Fonte: SPRINGER HEIDELBERG Publicador: SPRINGER HEIDELBERG
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.16%
In ostariophysan fish, the detection of alarm substance released from the skin of a conspecific or a sympatric heterospecific may elicit alarm reactions or antipredator behavioral responses. In this study, experiments were performed to characterize and quantify the behavioral response threshold of Leporinus piau, both individually and in schools, to growing dilutions of conspecific (CAS) and heterospecific skin extract (HAS). The predominant behavioral response to CAS stock stimulation was biphasic for fish held individually, with a brief initial period of rapid swimming followed by a longer period of immobility or reduced swimming activity. As the dilution of skin extract was increased, the occurrence and magnitude of the biphasic alarm response tended to decrease, replaced by a slowing of locomotion. Slowing was the most common antipredator behavior, observed in 62.5% of animals submitted to HAS stimulation. School cohesion, measured as proximity of fish to the center of the school, and swimming activity near the water surface significantly increased after exposure to CAS when compared with the control group exposed to distilled water. Histological analysis of the epidermis revealed the presence of Ostariophysi-like club cells. The presence of these cells and the behavioral responses to conspecific and heterospecific skin extract stimulation suggest the existence of a pheromone alarm system in L. piau similar to that in Ostariophysi...

Territorialidade e nível do adversário: efeitos nas respostas hormonais e comportamentais em jogadores de basquetebol; Territoriality and level of the opponent: effects in hormonal and behavioral responses in basketball players

Arruda, Ademir Felipe Schultz de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 17/04/2014 PT
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46.18%
O objetivo da presente dissertação foi investigar o efeito da territorialidade e do nível do adversário nas respostas hormonais e comportamentais de jogadores de basquetebol. Para tanto, foram realizados dois estudos. No primeiro, investigou-se o efeito da territorialidade nas respostas hormonais e comportamentais decorrentes de jogos oficiais de basquetebol. Dezoito jogadores, do sexo masculino, de duas equipes da categoria sub-19 (ranqueadas em primeiro e segundo lugar na competição) foram avaliados. As equipes jogaram entre si e, portanto, cada equipe realizou um jogo "em casa" e um jogo "fora de casa". Amostras de saliva foram coletadas antes e após as duas partidas, para análise dos hormônios testosterona (T) e cortisol (C). Antes do aquecimento, os atletas responderam um questionário de ansiedade pré-competitiva, (Competitive State Anxiety Inventory-2; CSAI-2), e 30 minutos após a partida, classificaram a magnitude do esforço através do método da percepção subjetiva de esforço da sessão (PSE da sessão). A concentração de T PRÉ-jogo foi maior na condição "casa" (versus "fora de casa"); verificou-se um aumento da concentração de T e C do momento PRÉ- para o PÓS-jogo, independentemente do local do jogo; correlações significantes foram apresentadas entre as respostas hormonais e comportamentais. Esses resultados sugerem a ocorrência do fenômeno da territorialidade...

Behavioral responses evoked in honey bee workers by Dufour gland extracts (Hymenoptera : Apidae)

Abdalla, Fábio Camargo; Cruz-Landim, Carminda da
Fonte: California State University Publicador: California State University
Tipo: Artigo de Revista Científica Formato: 673-678
ENG
Relevância na Pesquisa
55.97%
A series of experiments was performed to assess possible roles of the honey bee Dufour gland secretion. Bioassays with extracts of queen and worker glands from two colonies were made under artificial conditions, in which nestmate and non-nestmate forager workers were tested. The results demonstrate that forager workers display behavioral responses when exposed to Dufour gland extracts of nestmates, but remain indifferent when exposed to non-nestmate extracts. Also, the results demonstrate that forager workers are attracted by virgin queen gland extracts, and repelled by forager worker extracts. The data demonstrate that the Dufour gland secretion is colony- and caste-specific. The attractant remains in the nest. The repellent effect of forager worker extracts is interpreted as an alarm-like pheromone. The attractant effect of virgin queen extracts could be useful in the swarming process to attract scout bees to the eventual founder virgin queen or to attract old foragers to the virgin queen that remains in the nest.

Threat-Sensitive Behavioral Responses to Concentrations of Water-Borne Cues from Predation

Kesavaraju, Banugopan; Damal, Kavitha; Juliano, Steven A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/2007 EN
Relevância na Pesquisa
46.14%
Aquatic organisms often detect predators via water-borne chemical cues, and respond by showing reduced activity. Prey responses may be correlated with the concentration of predation cues, which would result in graded antipredator behavioral responses that adjust potentially costly behavioral changes to levels that are commensurate with the risk of predation. Larvae of the predatory mosquito Toxorhynchites rutilus prey upon other container-dwelling insects, including larvae of the mosquito Ochlerotatus triseriatus. Previous work has established that O. triseriatus reduce movement, foraging, and time below the surface, and increase the frequency of resting at the surface, in the presence of water-borne cues from predation by T. rutilus. We tested whether these responses by O. triseriatus are threat sensitive by recording behavior of fourth instar larvae in two runs of an experiment in which we created a series of concentrations (100, 10, 1, 0.1, and 0.01% and 100, 70, 40, 20, and 10%) of water that had held either O. triseriatus larvae alone (control) or a T. rutilus larva feeding on O. triseriatus (predation). We also tested whether associated effects on time spent feeding are threat sensitive by determining whether frequencies of filtering or browsing are also related to concentration of cues. The frequencies of resting and surface declined...

Physiological and Behavioral Responses to Interleukin-1β and LPS in Vagotomized Mice

Wieczorek, Marek; Swiergiel, Artur H.; Pournajafi-Nazarloo, Hossein; Dunn, Adrian J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 21/07/2005 EN
Relevância na Pesquisa
46.13%
It is well established that peripheral administration of interleukin-1 (IL-1) and lipopolysaccharide (LPS) can activate the hypothalamo-pituitary-adrenocortical (HPA) axis, alter brain catecholamine and indoleamine metabolism, and affect behavior. However, the mechanisms of these effects are not fully understood. Stimulation of afferents of the vagus nerve has been implicated in the induction of Fos in the brain, changes in body temperature, brain norepinephrine, and some behavioral responses. In the present study, the IL-1β - and LPS-induced changes in certain behaviors, HPA axis activation, and catecholamine and indoleamine metabolism were studied in mice following subdiaphragmatic vagotomy. IL-1β and LPS induced the expected decreases in sweetened milk, food intake, and locomotor activity, and the responses to IL-1β, but not LPS, were slightly attenuated in vagotomized mice. Subdiaphragmatic vagotomy also attenuated the IL-1β - and LPS-induced increases in plasma ACTH and corticosterone, but the attenuations of the responses to IL-1β were only marginally significant. There were also slight reductions in the responses in catecholamine and serotonin metabolism, and the increases in brain tryptophan in several brain regions. These results indicate that the vagus nerve is not the major pathway by which abdominal IL-1β and LPS effect behavioral...

Effect of Compassion Meditation on Neuroendocrine, Innate Immune and Behavioral Responses to Psychosocial Stress

Pace, Thaddeus W.W.; Negi, Lobsang Tenzin; Adame, Daniel D.; Cole, Steven P.; Sivilli, Teresa I.; Brown, Timothy D.; Issa, Michael J.; Raison, Charles L.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.13%
Meditation practices may impact physiological pathways that are modulated by stress and relevant to disease. While much attention has been paid to meditation practices that emphasize calming the mind, improving focused attention, or developing mindfulness, less is known about meditation practices that foster compassion. Accordingly, the current study examined the effect of compassion meditation on innate immune, neuroendocrine and behavioral responses to psychosocial stress and evaluated the degree to which engagement in meditation practice influenced stress-reactivity. Sixty-one healthy adults were randomized to 6 weeks of training in compassion meditation (n=33) or participation in a health discussion control group (n=28) followed by exposure to a standardized laboratory stressor (Trier Social Stress Test [TSST]). Physiologic and behavioral responses to the TSST were determined by repeated assessments of plasma concentrations of interleukin (IL)-6 and cortisol as well as total distress scores on the Profile of Mood States (POMS). No main effect of group assignment on TSST responses was found for IL-6, cortisol or POMS scores. However, within the meditation group, increased meditation practice was correlated with decreased TSST-induced IL-6 (rp =-0.46...

TRPV1-expressing primary afferents generate behavioral responses to pruritogens via multiple mechanisms

Imamachi, Noritaka; Park, Goon Ho; Lee, Hyosang; Anderson, David J.; Simon, Melvin I.; Basbaum, Allan I.; Han, Sang-Kyou
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.11%
The mechanisms that generate itch are poorly understood at both the molecular and cellular levels despite its clinical importance. To explore the peripheral neuronal mechanisms underlying itch, we assessed the behavioral responses (scratching) produced by s.c. injection of various pruritogens in PLCβ3- or TRPV1-deficient mice. We provide evidence that at least 3 different molecular pathways contribute to the transduction of itch responses to different pruritogens: 1) histamine requires the function of both PLCβ3 and the TRPV1 channel; 2) serotonin, or a selective agonist, α-methyl-serotonin (α-Me-5-HT), requires the presence of PLCβ3 but not TRPV1, and 3) endothelin-1 (ET-1) does not require either PLCβ3 or TRPV1. To determine whether the activity of these molecules is represented in a particular subpopulation of sensory neurons, we examined the behavioral consequences of selectively eliminating 2 nonoverlapping subsets of nociceptors. The genetic ablation of MrgprD+ neurons that represent ≈90% of cutaneous nonpeptidergic neurons did not affect the scratching responses to a number of pruritogens. In contrast, chemical ablation of the central branch of TRPV1+ nociceptors led to a significant behavioral deficit for pruritogens...

Innate immune, neuroendocrine and behavioral responses to psychosocial stress do not predict subsequent compassion meditation practice time

Pace, Thaddeus W.W.; Negi, Lobsang Tenzin; Sivilli, Teresa I.; Issa, Michael J.; Cole, Steven P.; Adame, Daniel D.; Raison, Charles L.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.13%
Increasing data suggest that meditation impacts stress-related physiological processes relevant to health and disease. For example, our group recently reported that the practice of compassion meditation was associated with reduced innate immune (plasma interleukin [IL]-6) and subjective distress responses to a standardized laboratory psychosocial stressor (Trier Social Stress Test [TSST]). However, because we administered a TSST after, but not prior to, meditation training in our initial study, it remained possible that associations between practice time and TSST outcomes reflected the fact that participants with reduced stress responses prior to training were more able to practice compassion meditation, rather than that meditation practice reduced stress responses. To help resolve this ambiguity, we conducted the current study to evaluate whether innate immune, neuroendocrine and behavioral responses to a TSST conducted prior to compassion meditation training in an independent sample of 32 medically health young adults would predict subsequent amount of meditation practice time during a compassion meditation training protocol identical to the one used in our first study. No associations were found between responses to a TSSTadministered prior to compassion meditation training and subsequent amount of meditation practice...

Hormonal and Behavioral Responses to Stress in Lactating and Non-lactating Female Common Marmosets (Callithrix jacchus)

Saltzman, Wendy; Abbott, David H.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.16%
In several mammalian species, hypothalamic-pituitary-adrenal (HPA) and behavioral responses to stressors are down-regulated in lactating females, possibly preventing stress-induced disruptions of maternal care. Experimental elevations of HPA axis hormones have been found to inhibit maternal behavior in lactating common marmoset monkeys (Callithrix jacchus), raising the question of whether lactating female marmosets also have blunted endogenous responses to stress. Therefore, we compared HPA and behavioral responses to standardized stressors in reproductively experienced female common marmosets that were undergoing ovulatory cycles and that either were (N=7) or were not lactating (N=8). Each marmoset underwent (1) a restraint stressor during the early follicular phase of the ovarian cycle (approximately 5 weeks postpartum for lactating females) and (2) exposure to a simulated hawk predator during the early to mid-luteal phase (approximately 7 weeks postpartum for lactating females). Lactating females were tested in the presence of one of their infants. Blood samples were collected before, during, and immediately after each test for determination of plasma adrenocorticotropic hormone (ACTH) and cortisol concentrations. Both stressors caused significant elevations in plasma ACTH and cortisol levels...

Long-lasting behavioral responses to stress involve a direct interaction of glucocorticoid receptors with ERK1/2–MSK1–Elk-1 signaling

Gutièrrez-Mecinas, María; Trollope, Alexandra F.; Collins, Andrew; Morfett, Hazel; Hesketh, Shirley A.; Kersanté, Flavie; Reul, Johannes M. H. M.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.11%
Stressful events are known to have a long-term impact on future behavioral stress responses. Previous studies suggested that both glucocorticoid hormones and glutamate acting via glucocorticoid receptors (GRs) and N-methyl d-aspartate (NMDA) receptors, respectively, are of critical importance for the consolidation of these long-lasting behavioral responses at the dentate gyrus, the gateway of the hippocampal formation. We found that an acute psychologically stressful event resulted in ERK1/2 phosphorylation (pERK1/2), which within 15 min led to the activation of the nuclear kinases MSK1 and Elk-1 in granule neurons of the dentate gyrus. Next, MSK1 and Elk-1 activation evoked serine-10 phosphorylation and lysine-14 acetylation in histone H3, resulting in the induction of the neuroplasticity-associated immediate-early genes c-Fos and Egr-1 in these neurons. The pERK1/2-mediated activation of MSK1 and Elk-1 required a rapid protein–protein interaction between pERK1/2 and activated GRs. This is a unique nongenomic mechanism of glucocorticoid hormone action in dentate gyrus granule neurons on long-lasting behavioral responses to stress involving direct cross-talk of GRs with ERK1/2–MSK1–Elk-1 signaling to the nucleus.

NEURAL AND BEHAVIORAL RESPONSES TO LOW-GRADE INFLAMMATION

Tarr, Andrew J.; Chen, Qun; Wang, Yufen; Sheridan, John F.; Quan, Ning
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.13%
Neural and behavioral responses after peripheral immune challenge have been observed in numerous studies. The majority of these studies have utilized relatively high doses of lipopolysaccharide (LPS) as the immune stimulant. Little attention has been given to the effects of LPS dose ranges that simulate low grade-inflammation. The current studies were designed to characterize neural and behavioral responses following low-dose LPS stimulation. Results show burrowing and open field activity was significantly impaired following a single i.p. injection of 10, but not 1, µg/kg of LPS. In addition, following repeated 1 µg/kg LPS administration for 10 days, animals showed the progressive development of motor deficits over time. To correlate behavior with CNS activity, cFos activation was determined in the paraventricular nucleus, nucleus of the solitary tract, central amygdaloid nucleus, and ventrolateral medulla. Data revealed there was a dose-dependent activation in all brain areas examined, but only the PVN showed significant activation by low-dose LPS. Additionally, animals that received 1 µg/kg of LPS for 8 days had PVN cFos activation similar to animals that received a single 10 µg/kg LPS injection. These data demonstrate neural and behavior responses can be induced by low-grade inflammation and chronic exposure to sub-threshold levels of LPS can precipitate significantly heightened neural and behavioral responses.

Chronic Inhibition of Dopamine β-Hydroxylase Facilitates Behavioral Responses to Cocaine in Mice

Gaval-Cruz, Meriem; Liles, Larry Cameron; Iuvone, Paul Michael; Weinshenker, David
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 27/11/2012 EN
Relevância na Pesquisa
46.11%
The anti-alcoholism medication, disulfiram (Antabuse), decreases cocaine use in humans regardless of concurrent alcohol consumption and facilitates cocaine sensitization in rats, but the functional targets are unknown. Disulfiram inhibits dopamine β-hydroxylase (DBH), the enzyme that converts dopamine (DA) to norepinephrine (NE) in noradrenergic neurons. The goal of this study was to test the effects of chronic genetic or pharmacological DBH inhibition on behavioral responses to cocaine using DBH knockout (Dbh −/−) mice, disulfiram, and the selective DBH inhibitor, nepicastat. Locomotor activity was measured in control (Dbh +/−) and Dbh −/− mice during a 5 day regimen of saline+saline, disulfiram+saline, nepicastat+saline, saline+cocaine, disulfiram+cocaine, or nepicastat+cocaine. After a 10 day withdrawal period, all groups were administered cocaine, and locomotor activity and stereotypy were measured. Drug-naïve Dbh −/− mice were hypersensitive to cocaine-induced locomotion and resembled cocaine-sensitized Dbh +/− mice. Chronic disulfiram administration facilitated cocaine-induced locomotion in some mice and induced stereotypy in others during the development of sensitization, while cocaine-induced stereotypy was evident in all nepicastat-treated mice. Cocaine-induced stereotypy was profoundly increased in the disulfiram+cocaine...

The Stepwise Behavioral Responses: Behavioral Adjustment of the Chinese Rare Minnow (Gobiocypris rarus) in the Exposure of Carbamate Pesticides

Ren, Zongming; Liu, Liang; Fu, Rongshu; Miao, Mingsheng
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.17%
In order to illustrate the behavioral regulation in environmental stress, the behavioral responses of the Chinese rare minnow (Gobiocypris rarus) to arprocarb, carbofuran, and oxamyl were analyzed with an online monitoring system. The Self-Organizing Map (SOM) was used to define the patterns of the behavioral data obtained from treatments at concentrations of 0.1 toxic unit (TU), 1 TU, 2 TU, 5 TU, 10 TU, and 20 TU and a control. In certain cases, differences among the carbamate pesticides (CPs) tested were observed. The profiles of behavioral strength (BS) in SOM varied according to the concentration used. The time of the first significant decrease of the BS varied inversely with the CP concentrations. The results suggested that the behavioral regulation in the stepwise behavioral responses (SBR) was evident. The primary movement behaviors shown by the SBR model included no effect, stimulation, acclimation, adjustment (readjustment), and toxic effect, especially at the lower concentrations. However, higher stress (10 TU and 20 TU) might limit the function of the behavioral adjustment produced by the intrinsic response mechanisms. It was concluded that SBR, which were affected by both the concentration and the exposure time...

Neurophysiological and Behavioral Responses to Music Therapy in Vegetative and Minimally Conscious States

O’Kelly, Julian; James, L.; Palaniappan, R.; Taborin, J.; Fachner, J.; Magee, W. L.
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 25/12/2013 EN
Relevância na Pesquisa
46.18%
Assessment of awareness for those with disorders of consciousness is a challenging undertaking, due to the complex presentation of the population. Debate surrounds whether behavioral assessments provide greatest accuracy in diagnosis compared to neuro-imaging methods, and despite developments in both, misdiagnosis rates remain high. Music therapy may be effective in the assessment and rehabilitation with this population due to effects of musical stimuli on arousal, attention, and emotion, irrespective of verbal or motor deficits. However, an evidence base is lacking as to which procedures are most effective. To address this, a neurophysiological and behavioral study was undertaken comparing electroencephalogram (EEG), heart rate variability, respiration, and behavioral responses of 20 healthy subjects with 21 individuals in vegetative or minimally conscious states (VS or MCS). Subjects were presented with live preferred music and improvised music entrained to respiration (procedures typically used in music therapy), recordings of disliked music, white noise, and silence. ANOVA tests indicated a range of significant responses (p ≤ 0.05) across healthy subjects corresponding to arousal and attention in response to preferred music including concurrent increases in respiration rate with globally enhanced EEG power spectra responses (p = 0.05–0.0001) across frequency bandwidths. Whilst physiological responses were heterogeneous across patient cohorts...

Memory suppression can help people “unlearn” behavioral responses —but only for non-emotional memories

Sakaki, Michiko; Kuhbandner, Christof; Mather, Mara; Pekrun, Reinhard
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/2014 EN
Relevância na Pesquisa
46.2%
When encountering reminders of memories that we prefer not to think about, we often try to exclude those memories from awareness. Past studies revealed that such suppression attempts can reduce subsequent recollection of unwanted memories. The current study examined whether the inhibitory effects extend even to associated behavioral responses. Participants learned cue-target pairs for emotional and non-emotional targets, and were additionally trained in behavioral responses for each cue. Afterwards, they were shown the cues and instructed either to think or to avoid thinking about the targets without performing any behaviors. In a final test phase, behavioral performance was tested for all cues. When targets were neutral, participants’ attempts to avoid retrieval reduced accuracy and increased reaction times in generating behavioral responses associated with cues. By contrast, behavioral performance was not affected by suppression attempts when targets were emotional. These results indicate that controlling unwanted recollection is powerful enough to inhibit associated behavioral responses – but only for non-emotional memories.

Planarian Phototactic Assay Reveals Differential Behavioral Responses Based on Wavelength

Paskin, Taylor R.; Jellies, John; Bacher, Jessica; Beane, Wendy S.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 10/12/2014 EN
Relevância na Pesquisa
46.2%
Planarians are free-living aquatic flatworms that possess a well-documented photophobic response to light. With a true central nervous system and simple cerebral eyes (ocelli), planarians are an emerging model for regenerative eye research. However, comparatively little is known about the physiology of their photoreception or how their behavior is affected by various wavelengths. Most phototactic studies have examined planarian behavior using white light. Here, we describe a novel planarian behavioral assay to test responses to small ranges of visible wavelengths (red, blue, green), as well as ultraviolet (UV) and infrared (IR) which have not previously been examined. Our data show that planarians display behavioral responses across a range of wavelengths. These responses occur in a hierarchy, with the shortest wavelengths (UV) causing the most intense photophobic responses while longer wavelengths produce no effect (red) or an apparent attraction (IR). In addition, our data reveals that planarian photophobia is comprised of both a general photophobic response (that drives planarians to escape the light source regardless of wavelength) and wavelength-specific responses that encompass specific behavioral reactions to individual wavelengths. Our results serve to improve the understanding of planarian phototaxis and suggest that behavioral studies performed with white light mask a complex behavioral interaction with the environment.

Weakly electric fish display behavioral responses to envelopes naturally occurring during movement: implications for neural processing

Metzen, Michael G.; Chacron, Maurice J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.16%
How the brain processes natural sensory input remains an important and poorly understood problem in neuroscience. The efficient coding hypothesis asserts that the brain’s coding strategies are adapted to the statistics of natural stimuli in order to efficiently process them, thereby optimizing their perception by the organism. Here we examined whether gymnotiform weakly electric fish displayed behavioral responses that are adapted to the statistics of the natural electrosensory envelopes. Previous studies have shown that the envelopes resulting from movement tend to consist of low (<1 Hz) temporal frequencies and are behaviorally relevant whereas those resulting from social interactions consist of higher (>1 Hz) temporal frequencies that can thus mask more behaviorally relevant signals. We found that the self-generated electric organ discharge frequency follows the detailed time course of the envelope around a mean value that is positively offset with respect to its baseline value for temporal frequencies between 0.001 Hz and 1 Hz. The frequency-following component of this behavioral response decreased in magnitude as a power law as a function of the envelope frequency and was negligible for envelope frequencies above 1 Hz. In contrast...

Respostas fisiológicas e comportamentais de recém-nascidos pré-termos submetidos a duas técnicas de banho de imersão: ensaio clínico cruzado; Physiological and behavioral responses of preterm newborn underwent to two immersion baths techniques: cross-over clinical trial

Freitas, Patricia de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/05/2015 PT
Relevância na Pesquisa
56.14%
Introdução: a revisão de literatura aponta que os recém-nascidos submetidos ao banho de imersão produzem menor variação térmica pós-banho comparado aos submetidos ao banho com esponja. No Brasil, o Ministério da Saúde vem capacitando profissionais que atuam em unidades de internação neonatal para implementar o Método Mãe Canguru e, entre outras práticas, recomenda que o recém-nascido pré-termo (RNPT) e com baixo peso seja submetido ao banho de imersão envolto em cueiro ou lençol, sugerindo mudança da prática hegemônica do banho com esponja ou banho de imersão convencional. No entanto, a técnica de banho de imersão recomendada carece de evidências científicas quanto a sua segurança em relação às repercussões na estabilidade da temperatura corporal (T), frequência cardíaca (FC), cortisol salivar (CS) e comportamental em RNPT. Hipótese: os RNPT submetidos ao banho de imersão envoltos em lençol (BIE) apresentam respostas fisiológicas e comportamentais similares aos submetidos à técnica de banho de imersão convencional (BIC), nos primeiros 20 minutos pós-banho. Objetivo: avaliar os parâmetros fisiológicos e comportamentais de RNPT submetidos ao banho de imersão envolto em lençol (BIE) e banho de imersão convencional (BIC). Método: ensaio clínico randomizado cruzado com amostra composta por 43 RNPT...

The Effects of Tail Biopsy for Genotyping on Behavioral Responses to Nociceptive Stimuli

Morales, Maria Elena P.; Gereau, Robert W.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 30/07/2009 EN
Relevância na Pesquisa
46.22%
Removal of a small segment of tail at weaning is a common method used to obtain tissue for the isolation of genomic DNA to identify genetically modified mice. When genetically manipulated mice are used for pain research, this practice could result in confounding changes to the animals' responses to noxious stimuli. In this study, we sought to systematically investigate whether tail biopsy representative of that used in standard genotyping methods affects behavioral responses to a battery of tests of nociception. Wild-type littermate C57BL/6J and 129S6 female and male mice received either tail biopsies or control procedural handling at Day 21 after birth and were then tested at 6–9 weeks for mechanical and thermal sensitivity. C57BL/6J mice were also tested in the formalin model of inflammatory pain. In all tests performed (von Frey, Hargreaves, modified Randall Selitto, and formalin), C57BL/6J tail-biopsied animals' behavioral responses were not significantly different from control animals. In 129S6 animals, tail biopsy did not have a significant effect on behavioral responses in either sex to the von Frey and the modified Randall-Selitto tests of mechanical sensitivity. Interestingly, however, both sexes exhibited small but significant differences between tail biopsied and control responses to a radiant heat stimulus. These results indicate that tail biopsy for genotyping purposes has no effect on nocifensive behavioral responses of C57BL/6J mice...