Aversive Stimulus
Mostrando 1-12 de 31 artigos, teses e dissertações.
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1. Desamparo aprendido e imunização em humanos: avaliação metodológica/conceitual e uma proposta experimental / Learned helplessness and immunization in humans: methodological/conceptual evaluation and an experimental proposal
The results of learned helplessness studies with humans have been inconsistent. This is probably due to the systematic contiguity between the end of the aversive stimulus and the immediately preceding response during the uncontrollability session, which mimics an accidental control condition. Three experiments were conducted to establish a procedure with ade
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 03/09/2012
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2. Subchronic effects of fluoxetine on conditioned suppression produced by a hot air blast
Conditioned suppression is an animal model of anxiety disorders that has been broadly used to investigate the behavioral effects of different drugs. However, various methodological variables (e.g., the type of aversive stimulus) that supposedly interfere with the acquisition of conditioned suppression may also contribute to conflicting results among the stud
Psychol. Neurosci.. Publicado em: 2012-06
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3. Discriminated conditioned suppression in rats
This experiment evaluated the effects of superimposing the Estes-Skinner Conditioned Emotional Response (CER) procedure on one of two components of a multiple schedule. The question was whether CER conditioning occurred under contextual control. The procedure had four experimental phases: (1) baseline of operant responding under a two-component multiple sche
Psychol. Neurosci.. Publicado em: 2012-06
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4. Differential behavioral outcomes of 3,4-methylenedioxymethamphetamine (MDMA-ecstasy) in anxiety-like responses in mice
Anxiolytic and anxiogenic-like behavioral outcomes have been reported for methylenedioxymethamphetamine (MDMA or ecstasy) in rodents. In the present experiment, we attempted to identify behavioral, hormonal and neurochemical outcomes of MDMA treatment to clarify its effects on anxiety-related responses in 2-month-old Balb/c male mice (25-35 g; N = 7-10 mice/
Brazilian Journal of Medical and Biological Research. Publicado em: 2011-05
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5. Role of nitric oxide in the periaqueductal gray in defensive behavior in mice: influence of prior local N-methyl-D-aspartate receptor activation and aversive condition
Glutamate N-methyl-D-aspartate (NMDA) receptor activation within the dorsal column of the periaqueductal gray (dPAG) leads to antinociceptive, autonomic, and behavioral responses characterized as the fear reaction. Activation of NMDA receptors in the brain increases nitric oxide (NO) synthesis, and NO has been proposed to be a mediator of the aversive action
Psychology & Neuroscience. Publicado em: 2010-06
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6. Detecção de reatividade divergente pelo teste de labirinto e sua implicação em indicadores fisiológicos e musculares de estresse em suínos sob diferentes manejos pré-abate / Detection of reactivity divergent by maze test and its implication in physiological indicators and muscle of stress in pigs under different handling pre-slaughter
Numerous studies have demonstrated the relationship between behavioral and physiological measures of stress in pigs at slaughter and subsequent effects on meat quality. One way to study this relationship is through behavioral tests. The test Y maze is used especially to determine the relationship of aversion front the different procedures for handling. The o
Publicado em: 2010
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7. The terrestrial Gastropoda megalobulimus abbreviatus as a useful model for nociceptive experiments : effects of morphine and naloxone on thermal avoidance behavior
We describe the behavior of the snail Megalobulimus abbreviatus upon receiving thermal stimuli and the effects of pretreatment with morphine and naloxone on behavior after a thermal stimulus, in order to establish a useful model for nociceptive experiments. Snails submitted to non-functional (22ºC) and non-thermal hot-plate stress (30ºC) only displayed exp
Publicado em: 2010
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8. L-histidine reduces inhibitory avoidance in Carassius auratus submitted to cerebellar ablation
The effect of post-training treatment with L-histidine (LH) on the memory consolidation of inhibitory avoidance was investigated in Carassius auratus submitted to cerebellar ablation. The inhibitory avoidance procedure included 3 days: one habituation day, one training day (5 trials, T1-T5) and one test day. On the training day, each fish was placed individu
Brazilian Journal of Medical and Biological Research. Publicado em: 2009-01
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9. Efeito do pentilenotetrazol e do midazolam na aquisição e na expressão da resposta defensiva de ratos submetidos ao condicionamento olfatório de medo
Pavlovian fear conditioning or first-order fear conditioning has been widely used to study the neuroanatomical, cellular and molecular basis of fear. This paradigm occurs when an emotionally neutral stimulus is presented in conjunction with an aversive unconditioned stimulus (US). After one or several pairings the stimulus, previously neutral, acquires the a
Publicado em: 2009
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10. Papel do sistema histaminérgico nos processos de aprendizagem e memória em Carassius auratus após ablação cerebelar
This study investigated the effect of post-training treatment with L-histidine, Pyrilamine and Zolantidine on the memory consolidation of inhibitory avoidance in Carassius auratus submitted to cerebellar ablation. Cerebellar ablation was performed 3 days before the experiment. The inhibitory avoidance procedure included one habituation day, one training day
Publicado em: 2009
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11. Role of the cardiac nerve in the adaptive changes of heart rate in response to an aversive stimulus in Megalobulimus mogianensis
The effect of an aversive stimulus represented by contact with a hot plate on the heart rate of Megalobulimus mogianensis was evaluated with electrocardiogram recording in intact snails (N = 8). All stimulated animals showed an increase in heart rate, with mean values ranging from 35.6 ± 1.2 (basal heart rate) to 43.8 ± 0.9 bpm (post-stimulation heart rate
Brazilian Journal of Medical and Biological Research. Publicado em: 2008-05
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12. Investigação longitudinal dos efeitos de diferentes contingências com estímulos apetitivos e aversivos sobre o desamparo aprendido / Longitudinal research on the effects of different contingencies with appetitive and aversive stimuli upon learned helplessness
The learned helplessness hypothesis was put forward by Seligman &Maier in 1976 under the assumption of generality among all stimulus conditions, aversive or otherwise, and as an explanatory model of human depression. This proposition allowed for some experimental manipulations aimed at reversing the effect, using, among others things, positive reinforcement
Publicado em: 2007