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161.
The authors investigated the impact that 5 selected risk factors have on the treatment outcome of adolescent male sex offenders. The results indicated that the greatest risk factor among sex offenders was having a mother who had a substance abuse problem.  相似文献   
162.
The medium spiny neurons of the nucleus accumbens receive a unique convergence of dopaminergic and glutamatergic inputs from regions associated with motivational, cognitive, and sensory processes. Long-term forms of plasticity in the nucleus accumbens associated with such processes as appetitive learning and drug addiction may require coactivation of both dopamine D1 and glutamate N-methyl-D-aspartate (NMDA) receptors. This notion implies that an intracellular mechanism is likely to be involved in these long-term neuroadaptive processes. The present series of experiments examined the effects of intra-accumbens microinfusion of protein kinase inhibitors on acquisition of an instrumental task, lever-pressing for food. Male Sprague-Dawley rats were bilaterally implanted with chronic indwelling cannulae aimed at the nucleus accumbens core. Following recovery, animals were food-restricted and subsequently trained for operant responding. The broad-based serine/threonine kinase inhibitor H-7 (5 or 27 nmol per side) dose-dependently impaired learning when infused immediately after testing on days 1-4. Rp-cAMPS, a cAMP-dependent protein kinase (PKA) inhibitor, also impaired learning regardless of whether it was infused immediately before (5 or 20 nmol) or immediately after (10 nmol) testing on days 1-4. Rp-cAMPS (10 nmol) also inhibited learning when infused 1 h after testing, though to a lesser extent than when administered before or immediately after testing. The PKA stimulator Sp-cAMPS (5 or 20 nmol) also impaired learning when infused before testing, suggesting that there is an optimal level of PKA activity required for learning. None of the drugs used produced nonspecific motor or feeding effects. These results provide evidence supporting the involvement of nucleus accumbens PKA in appetitive learning and suggest that this kinase may be involved in long-term changes associated with this and other motivationally based neuroadaptive processes.  相似文献   
163.
The fear conditioning paradigm is used to investigate the roles of various genes, neurotransmitters, and substrates in the formation of fear learning related to contextual and auditory cues. In the brain, nitric oxide (NO) produced by neuronal nitric oxide synthase (nNOS) functions as a retrograde neuronal messenger that facilitates synaptic plasticity, including the late phase of long-term potentiation (LTP) and formation of long-term memory (LTM). Evidence has implicated NO signaling in synaptic plasticity and LTM formation following fear conditioning, yet little is known about the role of the nNOS gene in fear learning. Using knockout (KO) mice with targeted mutation of the nNOS gene and their wild-type (WT) counterparts, the role of NO signaling in fear conditioning was investigated. Plasma levels of the stress hormone corticosterone were measured to determine the relationship between physiological and behavioral response to fear conditioning. Contextual fear learning was severely impaired in male and female nNOS KO mice compared with WT counterparts; cued fear learning was slightly impaired in nNOS KO mice. Sex-dependent differences in both contextual and cued fear learning were not observed in either genotype. Deficits in contextual fear learning in nNOS KO mice were partially overcome by multiple trainings. A relationship between increase in plasma corticosterone levels following footshock administration and the magnitude of contextual, but not cued freezing was also observed. Results suggest that the nNOS gene contributes more to optimal contextual fear learning than to cued fear learning, and therefore, inhibition of the nNOS enzyme may ameliorate context-dependent fear response.Anxiety disorders, such as post-traumatic stress disorder (PTSD), constitute the most prevalent mental illnesses in the United States, costing nearly one-third of the country''s total health bill (Greenberg et al. 1999). The treatment of these disorders requires overcoming complications such as reluctance to seek mental health treatment and an extremely high comorbidity rate with other affective disorders, reaching 80% (Brady 1997; Solomon and Davidson 1997). Emerging evidence suggests that dysfunctions underlying acquired anxiety and PTSD include an abnormal reaction to stress, which is mediated by specific neurochemical and neuroanatomical substrates (Yehuda and McFarlane 1995; Adamec 1997). Pharmacotherapies that target neuronal signaling molecules, such as nitric oxide (NO), may play a role in the treatment of these disorders.In the brain, N-methyl-d-aspartate receptor (NMDAR) activation and calcium influx into the cell activates the neuronal nitric oxide synthase (nNOS) enzyme to produce NO, which has the role of retrograde messenger (Snyder 1992). NO is involved in memory formation and synaptic plastic events such as late-phase long-term potentiation (LTP) (Lu et al. 1999; Arancio et al. 2001; Puzzo et al. 2006). Behavioral evidence in invertebrates (Lewin and Walters 1999; Muller 2000; Kemenes et al. 2002; Matsumoto et al. 2006) and vertebrates (Medina and Izquierdo 1995; Rickard et al. 1998; Ota et al. 2008) suggest that NO has a major role in consolidation of long-term memory (LTM). Recently, studies have shown that site-specific pharmacological blockade of NO signaling in rats impairs contextual (Resstel et al. 2008) and cued (Schafe et al. 2005) fear learning. However, the role of the nNOS gene in fear conditioning has not been investigated.In the present study, fear conditioning was investigated in homozygous nNOS knockout (KO) and wild-type (WT) mice. In the fear-conditioning paradigm, the association of a footshock (unconditioned stimulus; US), with a specific context and a neutral stimulus (auditory cue) results in learned fear. Re-exposure to the conditioning context and to the previously neutral auditory cue (conditioned stimulus; CS) elicits a freezing response in the absence of the aversive US. Thus, the fear-conditioning paradigm includes both contextual and cued fear learning components, which can be measured in separate tests. Fear conditioning recruits both the amygdala (emotional cue learning) and the hippocampus (spatial/contextual learning) (Phillips and LeDoux 1992; Goosens and Maren 2004; Mei et al. 2005). The involvement of these brain regions in fear learning and anxiety has been confirmed by animal and human imaging studies (LeDoux 1998; Rauch et al. 2006).We report that nNOS KO mice showed a severe deficiency in contextual fear learning and a less marked deficit in cued fear learning compared with WT mice after a single fear-conditioning session. This deficiency was partially improved by multiple (four) fear-conditioning sessions. In addition, we observed that plasma levels of corticosterone, the primary stress hormone in rodents, are related to contextual fear learning ability.  相似文献   
164.
Although it may be oversimplistic to regard the cognitive and behavioral effects of anxiety as simply being due to associated increases in arousal, this is essentially what many theories of anxiety do. Indeed, some theorists go so far as to equate anxiety with arousal. This experiment questions the appropriateness of this assumption by showing that increases in arousal do not necessarily accompany increases in anxiety. First, a 14-item arousal questionnaire was validated using factor analytic and multivariate analysis of variance techniques. Two factors were identified: cognitive activation and somatic activation. The validated questionnaire was then administered to eight very experienced rock-climbers in six different environments, together with a cognitive-somatic anxiety questionnaire. Heartrate and oral temperature were also measured. The six environments were: morning and evening; during a prolonged “bouldering” session; and immediately prior to leading pitches at two grade, one grade and zero grades below their leading capacity. The experimental hypothesis that activation would be increasingly impaired in the latter two conditions while anxiety would continue to increase, was confirmed by a multivariate analysis of variance (p<0.001). The results are interpreted as supporting the sort of two-factor theory of arousal that has been proposed by Gray.  相似文献   
165.
Child behavior ratings were made by 17 mothers and fathers of the same child. Agreement was computed for each parent pair under the following experimental conditions: (1) Ratings of their own child's behavior in general (CBC); (2) ratings of own child based on observations of him/her in a videotaped sample; (3) ratings of an unknown child based on observations of him/her in a videotaped sample; and (4) ratings of the videotaped sample of own child and unknown child using a one minute time-sampling procedure. Parents achieved higher rates of agreement (X=.81) than have previously been reported. Increasing the specificity of the behavior being rated did not significantly affect agreement. Those parent pairs who agreed the most did not necessarily spend a large amount of time in the same kind of situations with their child. Agreement was significantly greater when parents rated their own children's videotaped behavior sample as opposed to that of an unknown child.  相似文献   
166.
The hypothesis that either an angry emotional state or the expression of aggressive behavior facilitates sexual arousal has been the subject of considerable speculation but relatively little research. In a series of studies, Barclay found that anger increased sexual arousal as measured by the amount of sexual imagery produced in response to TAT-like stimuli that depicted males and females in dominant and submissive roles. In the present research, a series of experiments was conducted to determine whether such facilitation can be generalized beyond the specific procedures used by Barclay. Subjects (151 males and 136 females) in three experiments were angered by being negatively evaluated by a confederate identified as a fellow subject. Some subjects were subsequently given an opportunity to aggress; additionally, some subjects were exposed to male- and female-dominant pictorial stimuli. Results indicated that neither anger instigation nor the opportunity to engage in aggressive acts influenced self-reported sexual arousal. There was consistent evidence, however, that portrayals of dominance influenced perceptions of the stimulus person's sexuality. Though anger and aggression do not seem to facilitate sexual arousal, dominance cues (which can be confounded with anger manipulation) clearly elicit perceptions of sexuality.  相似文献   
167.
Attacks by dominant colony males of a domesticated rat strain on conspecific strangers introduced into the colony include both a full range of threat displays and actual biting attack. These dominant males attack and bite both anesthetized and unanesthetized strangers, but threat displays and bites to anesthetized rats are limited. Lesions resulting from these bites are nonrandomly distributed, with most damage to the head and upper back and very few bites to ventral surfaces. When introduced strangers were left in the colonies for several days, 66% were killed, indicating that domesticated rats are capable of lethal attacks on conspecifics without external provocation.  相似文献   
168.
Systematic desensitization therapy (SDT) is considered to be a technique of established effectiveness in reducing monosymptomatic fears (Paul, 1969a, 1969b), yet little systematic research has been done to investigate the merit of desensitization procedures in modifying children's behavior. The few available controlled studies (Miller et al., 1972; Obler and Terwilliger, 1970; Oliver, 1971) on desensitization with children have produced equivocal results. Although imagery and relaxation have been reported of benefit when used separately (Graziano and Kean, 1971; Lazarus and Abramovitz, 1962), evidence suggests that the usual combination of imagery and relaxation is not effective in reducing children's fears (Miller et al., 1972). Investigators in this area have often modified traditional SDT to include alternatives to imagery such as pictures, drawings, play (Cassell, 1965; Lazarus, 1960; Obler and Terwilliger, 1970; Patterson, 1965), or in vivo exposure to the feared stimulus (Obler and Terwilliger, 1970). Relaxation has often been replaced with other responses thought to be incompatible with anxiety such as eating (Jones, 1924). Another deviation from traditional SDT has been the delivery of positive reinforcement (food, praise, or toys) contingent upon the child's approaching the feared object (Obler and Terwilliger, 1970; Patterson, 1965). On the basis of such varied techniques, it is impossible to determine which of these procedures constitutes an effective treatment method for children. In the following study, three desensitization procedures involving graded exposure to the feared stimulus (darkness) through symbolic play, were compared to no-treatment and placebo control groups under differing instructional sets. Treatments were designed to determine the therapeutic efficacy of play as a method of stimulus presentation with children, and to determine whether reciprocal inhibition, extinction, operant reinforcement, or instructional set contribute to fear reduction in desensitization with children.  相似文献   
169.
170.
Leigh B. Kelley 《Synthese》1988,76(1):83-121
This paper treats two problem cases in decision theory, the Newcomb problem and Reed Richter's Button III. Although I argue that, contrary to Richter, the latter case does not constitute a genuine counterexample to a standard general proposition of (causal) decision theory, I agree with and undertake to amplify his solution to the decision problem in Button III. I then apply the conclusions and distinctions in the foregoing treatment of Button III to the Newcomb problem and argue that a familiar version of the dominance argument for taking both boxes runs afoul of plausible general constraints on rational agency. The underlying theme of the paper is that basic considerations of epistemic coherence play an important role in dealing with problem cases in decision theory.  相似文献   
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