Unconditioned Fear
Mostrando 1-12 de 28 artigos, teses e dissertações.
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1. Critical neuropsychobiological analysis of panic attack- and anticipatory anxiety-like behaviors in rodents confronted with snakes in polygonal arenas and complex labyrinths: a comparison to the elevated plus- and T-maze behavioral tests
Objective: To compare prey and snake paradigms performed in complex environments to the elevated plus-maze (EPM) and T-maze (ETM) tests for the study of panic attack- and anticipatory anxiety-like behaviors in rodents. Methods: PubMed was reviewed in search of articles focusing on the plus maze test, EPM, and ETM, as well as on defensive behaviors displaye
Rev. Bras. Psiquiatr.. Publicado em: 06/02/2017
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2. ROLE OF DORSAL AND VENTRAL HIPPOCAMPUS ON CONDITIONED AND UNCONDITIONED FEAR ELICITED BY DORSAL PERIAQUEDUCTAL GREY MATTER ELECTRICAL STIMULATION IN RATS / PARTICIPAÇÃO DO HIPOCAMPO DORSAL E VENTRAL NAS REAÇÕES DE DEFESA PRODUZIDAS PELO CONDICIONAMENTO CONTEXTUAL DE MEDO E PELA ESTIMULAÇÃO ELÉTRICA DA MATÉRIA CINZENTA PERIAQUEDUTAL DORSAL
This study investigates the role of the hippocampus in both unconditioned and conditioned defense behavior by examining the effects of pre-training electrolytic lesions to the dorsal and ventral hippocampus in male rats exposed to two types of threat stimuli: electrical stimulation of the DPAG and footshock. Our results indicate that ventral and dorsal lesio
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/03/2012
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3. Involvement of midbrain tectum neurokinin-mediated mechanisms in fear and anxiety
Electrical stimulation of midbrain tectum structures, particularly the dorsal periaqueductal gray (dPAG) and inferior colliculus (IC), produces defensive responses, such as freezing and escape behavior. Freezing also ensues after termination of dPAG stimulation (post-stimulation freezing). These defensive reaction responses are critically mediated by γ-amin
Brazilian Journal of Medical and Biological Research. Publicado em: 2012-04
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4. Envolvimento de receptores NK-1 e NK-3 no comportamento defensivo induzido pela estimulação elétrica da substância cinzenta periaquedutal dorsal / Involvement of NK-1 and NK-3 receptors on the defensive behavior induced by electrical stimulation of the dorsal periaqueductal gray.
A substância cinzenta periaquedutal dorsal (SCPd) é considerada uma das principais estruturas do teto mesencefálico envolvida no substrato neural da aversão a estímulos proximais. GABA e 5-HT são apontados como neurotransmissores envolvidos na modulação das respostas defensivas elaboradas na SCPd. Recentemente, mecanismos neurocininérgicos também t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 20/10/2011
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5. Gabaergic mechanisms of anterior and ventromedial hypothalamic nuclei in the expression of freezing in response to a light-conditioned stimulus
The amygdala, dorsal periaqueductal gray (dPAG), and medial hypothalamus have long been recognized to comprise a neural system responsible for the generation and elaboration of unconditioned fear in the brain. This neural substrate is well known to be under tonic inhibitory control exerted by γ-aminobutyric acid (GABA) mechanisms. Some evidence also suggest
Psychology & Neuroscience. Publicado em: 2011
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6. Strain and sex differences in fear conditioning: 22 kHz ultrasonic vocalizations and freezing in rats
Strain and sex differences in fear conditioning were investigated in two commonly used laboratory rats: Sprague Dawleys and Long-Evans. Twenty-two kHz ultrasonic vocalization (USV) distress calls and freezing behavior were used to measure fear responses to contextual and auditory conditioned stimuli (CSs), which were previously paired with a footshock uncond
Psychology & Neuroscience. Publicado em: 2009-12
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7. Involvement of GABAergic mechanisms of the dorsal periaqueductal gray and inferior colliculus on unconditioned fear
The fact that the dorsal periaqueductal gray (dPAG) and inferior colliculus (IC), together with superior colliculus, medial hypothalamus and amygdala, constitute the brain aversion system has been well-established. Stepwise increases in the intensity of electrical stimulation of dPAG or IC cause freezing and escape responses, which are followed by a freezing
Psychology & Neuroscience. Publicado em: 2009-06
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8. 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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9. Envolvimento de receptores 5-HT2A da substância cinzenta periaquedutal dorsal no medo condicionado e incondicionado de ratos / 5HT2 receptor mechanisms of the dorsal periaqueductal gray in the conditioned and unconditioned fear in rats
Sabe-se que o medo condicionado contextual (MCC) pode ativar diversas áreas mesencefálicas, como a Substância Cinzenta Periaquedutal Dorsal (SCPd). Diversos estudos avaliaram como mecanismos serotoninérgicos modulam o comportamento defensivo induzido pela estimulação elétrica da SCPd. Uma função proeminente dos receptores 5-HT2A é regular estados a
Publicado em: 2007
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10. SYSTEMIC ADMINISTRATION OF POLYAMINERGIC AGENTS MODULATE FEAR CONDITIONING IN RATS. / ADMINISTRAÇÃO SISTÊMICA DE AGENTES POLIAMINÉRGICOS MODULA A MEMÓRIA NA TAREFA DE MEDO CONDICIONADO EM RATOS
The polyamines, spermine, spermidine and putrescine, are a group of aliphatic amines that interact with diverse cellular targets such as nucleic acids and proteins. The polyamines may act as physiological modulators of N-methyl-D-aspartate (NMDA) receptors. The processes mediated by NMDA receptor include synaptic plasticity and formation of neural circuitry
Publicado em: 2006
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11. The brain decade in debate: III. Neurobiology of emotion
This article is a transcription of an electronic symposium in which active researchers were invited by the Brazilian Society of Neuroscience and Behavior (SBNeC) to discuss the advances of the last decade in the neurobiology of emotion. Four basic questions were debated: 1) What are the most critical issues/questions in the neurobiology of emotion? 2) What d
Brazilian Journal of Medical and Biological Research. Publicado em: 2001-03
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12. An egr-1 (zif268) Antisense Oligodeoxynucleotide Infused Into the Amygdala Disrupts Fear Conditioning
Studies of gene expression following fear conditioning have demonstrated that the inducible transcription factor, egr-1, is increased in the lateral nucleus of the amygdala shortly following fear conditioning. These studies suggest that egr-1 and its protein product Egr-1 in the amygdala are important for learning and memory of fear. To directly test this hy
Cold Spring Harbor Laboratory Press.