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41.
Electrical stimulation of the region of the lateral hypothalamus produced a consistent form of quiet-biting attack behavior in cats. In one series of experiments, cats, implanted with electrodes from which attack had been elicited, were anesthetized and then were injected with a bolus of 14C-2-deoxyglucose at the same time as electrical stimulation was delivered through the attack electrodes. Brains prepared for X-ray autoradiography revealed that lateral hypothalamic stimulation activated the classical medial forebrain bundle pathway supplying the septal region, diagonal band, lateral preoptic area, and ventral tegmental region. Stimulation of quiet-attack sites in perifornical hypothalamus resulted in the activation of a much more extensive projection system which included the central and lateral tegmental fields of the midbrain and pons, and central gray region, as well as the structures described above. In a second series of experiments, 3H-leucine was placed into the region of the electrode tip from which attack was elicited in order to identify more precisely the pathways arising from that site. In general, tritiated amino acid radioautography replicated the 14C-2-deoxyglucose findings. In addition, the amino acid radioautographic data revealed the presence of extensive projections from perifornical hypothalamus to such pontine structures as the nucleus locus coeruleus, motor nucleus of NV , and the lateral pontine tegmental field. The functional connections between the lateral hypothalamic “attack region” and lateral preoptic zone were also confirmed by electrophysiological methods. 相似文献
42.
目的:探讨语言熟练度对Stroop效应的影响及其背后的脑机制。材料与方法:17位被试参与本研究。被试母语为汉语,第二语言为英语。在被试完成中英文的stroop色字的任务过程中对被试进行fMRI扫描。结果:在色字相一致的条件下,中文任务与英文任务相比,双侧背侧枕叶及右侧背外侧前额叶有更强的激活; 反向比较,双侧腹侧枕叶有更强的激活。在色字不一致的条件下,中文任务与英文任务相比,双侧背外侧前额叶、右侧枕下回有更强的激活; 反向比较,并无显著激活的脑区。此外,中文Stroop效应引起左侧额下回显著的激活。英文Stroop效应中,左侧额下回无显著激活。结论:结合前人研究,我们得出,语言熟练度影响了对注意控制有重要作用的背外侧前额叶以及与反应抑制有关的左侧额下回在Stroop任务中的参与程度,进而影响了Stroop任务的表现 相似文献
43.
This research study focused on the evaluation of an emulated in-vehicle Active Traffic and Demand Management (ATDM) system on Interstate 66 in Northern Virginia. Traditional ATDM systems rely on infrastructure-mounted variable message signs (VMS) to provide information (speed limits, lane availability, etc.) to the traveling public. By providing information about dynamic roadway conditions on an in-vehicle device, the ATDM may improve driving safety and performance by allowing drivers to remain consistently aware of forthcoming traffic conditions and roadway requirements; even when external signage is inaccessible. This study represents an initial investigation of an emulated in-vehicle ATDM to provide developers with design guidance and ensure that unintended consequences, such as distraction, do not undermine the potential benefits.Twenty younger and 20 older participants, accompanied by a member of the research team, experienced the following ATDM features on an in-vehicle device (IVD) mounted to the dashboard: (1) dynamic speed limits, (2) dynamic lane use/shoulder control, (3) High Occupancy Vehicle (HOV) restrictions, and (4) roadway information from variable message signs. The IVD was equipped with auditory and visual alerts notifying the driver when relevant visual information was updated. Research questions addressed distraction and driver behavior associated with use of the system. Qualitative and quantitative participant data was acquired from the instrumented vehicle, various questionnaires, and researcher observation.Several key findings were uncovered: (1) The IVD, as tested, did not warrant classification as a source of distraction according to the NHTSA guidelines; v2) There was a significant difference in eye-glance durations to the IVD when comparing the VMS alerts to both the speed limit and lane management alerts; and (3) The speed limit alert motivated participants to alter their speed (per survey results and participant speed data). 相似文献
44.
We investigated public acceptance of conditionally automated (SAE Level 3) passenger cars using a questionnaire study among 9,118 car-drivers in eight European countries, as part of the European L3Pilot project. 71.06% of respondents considered conditionally automated cars easy to use while 28.03% of respondents planned to buy a conditionally automated car once it is available. 41.85% of respondents would like to use the time in the conditionally automated car for secondary activities. Among these 41.85%, respondents plan to talk to fellow travellers (44.76%), surf the internet, watch videos or TV shows (44%), observe the landscape (41.70%), and work (17.06%). The UTAUT2 (Unified Theory of Acceptance and Use of Technology) was applied to investigate the effects of performance and effort expectancy, social influence, facilitating conditions, and hedonic motivation on the behavioural intention to use conditionally automated cars. Structural equation analysis revealed that the UTAUT2 can be applied to conditional automation, with hedonic motivation, social influence, and performance expectancy influencing the behavioural intention to buy and use a conditionally automated car. The present study also found positive effects of facilitating conditions on effort expectancy and hedonic motivation. Social influence was a positive predictor of hedonic motivation, facilitating conditions, and performance expectancy. Age, gender and experience with advanced driver assistance systems had significant, yet small (<0.10), effects on behavioural intention. The implications of these results on the policy and best practices to enable large-scale implementation of conditionally automated cars on public roads are discussed. 相似文献
45.
Thirty preschoolers rated as hard to manage on Goodman's (R. Goodman, 1997) Strengths and Difficulties Questionnaire (SDQ), and a group of matched control children were observed and recorded on audiotape at home, interacting with their mothers (Time 1). At the 18-month follow-up home visits (Time 2), the children and mothers were filmed across 4 observation settings. Mother–child interactions were rated on affect, control, responsiveness and connectedness of communication. At Time 1, mothers of the hard to manage group used more negative control and engaged in fewer connected conversations than did mothers in the control group. At Time 2, mothers of the hard to manage group displayed higher levels of negative control and lower levels of positive control. These results are discussed in terms of the importance of examining connected communication and different observation contexts when examining dyadic mother–child interactions. 相似文献
46.
MMPI-2 scores of 307 female and 161 male chronic pain patients were analyzed by gender using a multivariate clustering method. Two subgroups were found for both sexes replicating previous results. The major subgroup corresponded to the classical "Conversion V" and the minor corresponded to the "Generally elevated" profile. The results also indicated a satisfactory internal consistency and a high discriminant validity of the Swedish version of the MMPI-2. 相似文献
47.
Claes E Evers-Kiebooms G Denayer L Decruyenaere M Boogaerts A Philippe K Legius E 《Journal of genetic counseling》2005,14(5):349-363
This prospective study evaluates emotional functioning and illness representations in 68 unaffected women (34 carriers/34
noncarriers) 1 year after predictive testing for BRCA1/2 mutations when offered within a multidisciplinary approach. Carriers had higher subjective risk perception of breast cancer
than noncarriers. Carriers who did not have prophylactic oophorectomy had the highest risk perception of ovarian cancer. No
differences were found between carriers and noncarriers regarding perceived seriousness and perceived control of breast and
ovarian cancer. Mean levels of distress were within normal ranges. Only few women showed an overall pattern of clinically
elevated distress. Cancer-specific distress and state-anxiety significantly decreased in noncarriers from pre- to posttest
while general distress remained about the same. There were no significant changes in distress in the group of carriers except
for ovarian cancer distress which significantly decreased from pre- to posttest. Our study did not reveal adverse effects
of predictive testing when offered in the context of a multidisciplinary approach. 相似文献
48.
兴奋性氨基酸(EAAs) 广泛分布于中枢神经系统,参与多种生理过程包括学习、记忆和伤害感受等。然而,EAAs 受体的过度兴奋却可引发一系列细胞事件,最终导致神经元的损伤与死亡。许多神经退行性疾病如早老性痴呆、癫痫和肌侧索硬化症等都与EAAs 的兴奋毒作用有关。目前的研究表明,由EAAs 受体过度兴奋所引发的细胞内钙超载是导致神经元死亡的最终途径 相似文献
49.
STRONG MILITARY FAMILIES INTERVENTION ENHANCES PARENTING REFLECTIVITY AND REPRESENTATIONS IN FAMILIES WITH YOUNG CHILDREN 下载免费PDF全文
M.M. Julian M. Muzik M. Kees M. Valenstein K. L. Rosenblum 《Infant mental health journal》2018,39(1):106-118
Military families face many challenges due to deployment and parental separation, and this can be especially difficult for families with young children. The Strong Military Families (SMF) intervention is for military families with young children, and consists of two versions: the Multifamily Group, and a Home‐based psychoeducational written materials program. The Multifamily Group was designed to enhance positive parenting through both educational components and in vivo feedback and support during separations and reunions between parents and children (n = 78 parents). In the present study, we examine parenting reflectivity and mental representations in mothers versus fathers in military families, service members versus civilian spouses/parenting partners, and before versus after participation in the SMF Multifamily Group and Home‐based interventions. Parenting reflectivity and mental representations were coded from the Working Model of the Child Interview (WMCI; C.H. Zeanah & D. Benoit, 1995). Results suggest that neither parenting reflectivity nor WMCI typology differs between mothers and fathers in military families, or between service members and civilian parenting partners. Furthermore, there was substantial stability in parenting reflectivity and WMCI typology from baseline to posttest, but participation in the Multifamily Group, relative to Home‐based, was associated with improvements in both parenting reflectivity and WMCI ratings from baseline to postintervention. 相似文献
50.
DC:0–5: DIAGNOSTIC CLASSIFICATION OF MENTAL HEALTH AND DEVELOPMENTAL DISORDERS OF INFANCY AND EARLY CHILDHOOD 下载免费PDF全文
Robert L.P. Klaehn 《Infant mental health journal》2018,39(4):489-491
The significant growth in the clinical literature on early childhood psychopathologysince the publication of the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood: Zero to Three–Revised (DC:0–3R; ZERO TO THREE) in 2005 necessitated substantial revisions to the manual, which resulted in the publication of the DC:0–5: Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood: Zero to Five (ZERO TO THREE) in 2016. In addition to the decision to extend the early childhood diagnoses to include children through age 5 years, significant revisions were made to many diagnoses, and new diagnostic categories were added such as the Relationship Specific Disorder of Infancy/Early Childhood. Other additions, such as guidance for the development of a Cultural Formulation for the young child and his or her family and the inclusion of functional impairment criteria also contribute to making the DC: 0–5a substantially more comprehensive and robust diagnostic framework than its predecessor. 相似文献