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31.
The fact that electrical stimulation of the lateral hypothalamus (LH) can be substituted for the delivery of a food pellet in typical schedule induced polydipsia was established and demonstrated the role of this part of the brain in the mediation of adjunctive behavior. The assumption that Δ9-tetrahydrocannabinol (Δ9-THC) and ethyl alcohol affect behavior because of a differential effect on the same LH mechanism was supported by the following evidence. Relatively small doses of Δ9-THC, 0.25, 0.375, and 0.50 mg/kg, enhanced adjunctive drinking; whereas, larger quantities of 0.625 and 0.75 mg/kg had no appreciable effects. The effect is somewhat specific, as it did not occur with strychnine sulfate, and rate dependent within limits as it was most pronounced in animals with low rates of responding or in animals when responding at a low rate. The effect of rate dependency was also apparent with fixed interval schedules of 2 and 4 min and a multiple schedule of a fixed interval and a signalled timed out period of nonreinforcement. Low rates of responding were enhanced by all doses of Δ9-THC, 1.0, 1.5, 2.0, 2,5, and 3.0 mg/kg, and there was an obvious dose related decrease in high rates. A similar effect was observed with low and high rates of electrical self-stimulation through implanted LH electrodes. The hypothesis that some drugs such as Δ9-THC and ethyl alcohol can enhance the positive feedback in an LH mediated motor control system by the facilitation of the same mechanism which initially generated the behavior was confirmed. Oral self administration of ethyl alcohol in a saccharin sweetened fluid enhanced recovered adjunctive drinking of the solution in quantities which should be sufficient to produce physical dependence if continued for relatively long periods. Recovered adjunctive drinking occurs in animals without food or water deprivation and it is an intense and persistent phenomenon.  相似文献   
32.
Bilateral skin conductance was recorded from 8 male and 8 female cigarette smokers and from 8 male and 8 female nonsmoker control subjects on two different days. On one day smokers smoked a cigarette prior to the recording session and on the other they remained abstinent. Subjects also engaged in tasks designed to differentially involve the cerebral hemispheres. SCR asymmetry was measured using two different indices. During both the resting and task periods smokers had larger SCRs in their right than left hands following smoking. Unlike control subjects during the first recording session, smokers did not show task related changes in SCR asymmetry. During tasks smokers showed smaller SCRs in both hands following smoking than following abstinence. Changes in SCR asymmetry associated with smoking were seen in subjects who smoked more cigarettes, reported more subjective craving, were more introverted, and indicated a preference for cognitive processes and strategies associated with the left hemisphere. Results are discussed in terms of relative involvement of the cerebral hemispheres following smoking and smoking abstinence.  相似文献   
33.
目的 探索青少年网络成瘾和睡眠时长在受校园欺凌与抑郁关系之间的中介作用,为青少年抑郁的预防干预提供依据。 方法 使用青少年健康相关危险行为问卷及CES - D抑郁量表,采用多阶段整群抽样法抽取徐州市4 190名青少年进行问卷调查。结果 在控制人口学等变量后,受校园欺凌、网络成瘾、睡眠时长对抑郁均有预测作用(r = 0.283,P<0.01;r = 0.331,P<0.01;r = - 0.184,P<0.01)。路径分析表明,网络成瘾在受校园欺凌和青少年抑郁之间起中介作用;网络成瘾和睡眠时长在受校园欺凌和青少年抑郁间起链式中介作用。结论 受校园欺凌不仅直接影响青少年抑郁,还通过网络成瘾和睡眠时长的链式中介作用间接影响青少年抑郁。可通过减少青少年网络使用和提高睡眠时长来降低受校园欺凌对青少年抑郁的影响。  相似文献   
34.
目的 分析心理健康教育干预(抑制控制训练联合积极情绪训练)对大学生手机依赖的干预效果。方法 对河南省3所高校600名大学生采用大学生手机成瘾倾向量表对其手机依赖情况进行调查,筛选存在手机依赖大学生随机分为对照组(66人)与观察组(67人),对照组给予抑制控制训练干预,观察组在此基础上联合积极情绪训练干预,比较2组干预前后手机依赖程度及心理健康状况的变化。结果 干预前2组手机成瘾量表评分、手机使用时间、心理弹性量表评分、认知情绪调节量表评分、抑制冲突效应量对比差异均无统计学意义(P>0.05)。干预后3个月,观察组手机成瘾量表评分(37.11±5.01)分,低于对照组的(41.25±6.33)分;观察组手机使用时间(2.72±0.71)h,低于对照组的(3.37±0.55)h;观察组认知情绪调节量表评分(88.79±5.66)分、心理弹性量表评分(76.63±3.97)分,高于对照组的(81.14±4.79)分、(71.75±4.55)分;观察组抑制冲突效应量(40.35±10.22)ms,低于对照组的(45.14±5.66)ms,差异均有统计学意义(P<0.01)。大学生手机成瘾倾向量表评分与认知情绪调节量表、心理弹性量表评分呈负相关(r=-0.397、-0.453,P<0.01),与冲突抑制效应量呈正相关(r=0.498,P<0.01)。结论 手机依赖直接影响大学生认知情绪调节及心理韧性;而以积极心理学为指导,开展抑制控制训练联合积极情绪训练,可减轻大学生手机依赖,提升认知情绪调节能力及心理韧性,改善自我控制能力,有助于促进其心理健康发展。  相似文献   
35.
The obesity epidemic and its metabolic consequences are a major public health problem both in the USA and globally. While the underlying causes are multifactorial, dysregulations within the brain–gut–microbiome (BGM) system play a central role. Normal eating behavior is coordinated by the tightly regulated balance between intestinal, extraintestinal and central homeostatic and hedonic mechanisms, resulting in stable body weight. The ubiquitous availability and marketing of inexpensive, highly palatable and calorie-dense food has played a crucial role in shifting this balance towards hedonic eating through both central (disruptions in dopaminergic signaling) and intestinal (vagal afferent function, metabolic toxemia, systemic immune activation, changes to gut microbiome and metabolome) mechanisms. The balance between homeostatic and hedonic eating behaviors is not only influenced by the amount and composition of the diet, but also by the timing and rhythmicity of food ingestion. Circadian rhythmicity affects both eating behavior and multiple gut functions, as well as the composition and interactions of the microbiome with the gut. Profound preclinical effects of intermittent fasting and time restricted eating on the gut microbiome and on host metabolism, mostly demonstrated in animal models and in a limited number of controlled human trials, have been reported. In this Review, we will discuss the effects of time-restricted eating on the BGM and review the promising effects of this eating pattern in obesity treatment.  相似文献   
36.
Background: Food addiction (FA) is a dysregulated eating pattern characterized by difficulties in controlling the intake of certain foods. There is an overlap in physical and mental health correlates of FA and post-traumatic stress disorder (PTSD). The purpose of this study was to examine sex differences in the rates of positive FA status in individuals with threshold/subthreshold PTSD, and to examine sex differences in the physical and mental health correlates of FA. Methods: Post-9/11 veterans/service members seeking PTSD treatment were recruited. Participants were diagnosed with PTSD via the administration of a clinical interview. FA status was determined using Modified Yale Food Addiction Scale-2, binary sex and body mass index were assessed with demographics questions. Results: Nearly half (43%) of the sample were women. There were no sex differences in the rates of FA, with an overall FA prevalence of 18%. There were no sex differences in FA symptom count in the whole sample (M = 1.63) or those with FA status (M = 6.21). Individuals with FA reported higher frequency of disordered eating, higher severity of PTSD, and depression symptoms. Conclusions: FA should be assessed in tandem with PTSD symptoms, as its prevalence in that sample is higher than in the general population, and it appears to affect both sexes at similar rates.  相似文献   
37.
38.
目的 比较三种手机成瘾量表在大学生手机成瘾测量中的一致性。方法 选取合肥市3所本科高校的1004名大学生,采用手机成瘾指数量表(MPAI)、智能手机依赖量表(SAS)、智能手机依赖量表简版(SAS-SV)同时进行手机成瘾倾向的测量,采用匹兹堡睡眠质量指数量表(PSQI)进行睡眠质量的测量,对122位学生在首次测评两周后进行重测。用Pearson相关系数描述三个量表得分之间的相关性;用符合率和Kappa系数衡量手机成瘾判定结果的一致性;用t检验、方差分析、logistic回归进行手机成瘾与大学生基本特征、相关因素的关联分析。结果 MPAI与SAS、MPAI与SAS-SV、SAS与SAS-SV得分之间的Pearson相关系数分别为0.72、0.74、0.95(P<0.010)。MPAI与SAS-SV判定手机成瘾结果的符合率为64.6%,Kappa值为0.32(P<0.001)。t检验显示,性别、专业属性与量表得分之间,三个量表结果一致;方差分析显示年级与量表得分之间,SAS与MPAI、SAS-SV的结果不一致。Logistic回归分析显示,性别、年级、专业属性与手机成瘾之间,MPAI、SAS-SV结果一致;睡眠与手机成瘾之间,MPAI、SAS-SV结果不一致。结论 三种量表的信效度均较好;量表得分的相关性较高,但MPAI和SAS-SV判定手机成瘾的一致性较差;在手机成瘾相关因素分析上,量表间存在不一致的现象。  相似文献   
39.
长沙市初中生网络成瘾的心理社会因素调查   总被引:5,自引:2,他引:5  
目的:调查长沙市初中生网络成瘾的发生率,探讨家庭和学校环境、应付方式对中学生网络成瘾的影响。方法:对长沙市的552名初中生进行问卷调查,应用Young网络成瘾诊断量表、家庭关怀度量表、学校满意度量表、应付方式问卷、焦虑、抑郁自评量表进行评估。结果:①580名初中生中,网络成瘾者38人(男生30人,女生8人),网络成瘾的发生率为6.55%。②网络成瘾与未成瘾学生在对学校和家庭满意度、应付方式方面有显著性差异(P<0.05)。③网络成瘾学生的焦虑、抑郁总分均显著高于未成瘾学生(P<0.05)。结论:感觉不到家庭的关怀、对学校生活不满意,焦虑、抑郁严重,遇到应激事件时采用消极的应对方式的初中生容易发生网络成瘾。  相似文献   
40.
Interviews were conducted with 101 heroin dependent persons entering a residential drug-free detoxification unit in 1989. These self-report data were compared with those previously collected in 1985-6 from 457 methadone maintenance patients. The detoxification patients injected less frequently, used less heroin, had been physically dependent for a shorter period and were more likely to be single, unemployed and to have been charged with a criminal offence in the last 12 months. It is suggested that these findings may indicate that addicts who use more heroin are less likely to seek drug-free detoxification. The wider implication of the finding is that future surveys of injecting drug users should assume that there are significant differences between heroin users entering different modalities of treatment.  相似文献   
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