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161.
In 1978, Berry and Thompson showed that the amount of theta (3–8 Hz) activity in the spontaneous hippocampal EEG predicted learning rate in subsequent eyeblink conditioning in rabbits. More recently, the absence of theta activity during the training trial has been shown to have a detrimental effect on learning rate. Here, we aimed to further explore the relationship between theta activity and classical eyeblink conditioning by determining how the relative power of hippocampal theta activity [theta/(theta + delta) ratio] changes during both unpaired control and paired training phases. We found that animals with a higher hippocampal theta ratio immediately before conditioning learned faster and also that in these animals the theta ratio was higher throughout both experimental phases. In fact, while the hippocampal theta ratio remained stable in the fast learners as a function of training, it decreased in the slow learners already during unpaired training. In addition, the presence of hippocampal theta activity enhanced the hippocampal model of the conditioned response (CR) and seemed to be beneficial for CR performance in terms of peak latency during conditioning, but did not have any effect when the animals showed asymptotic learning. Together with earlier findings, these results imply that the behavioral state in which hippocampal theta activity is absent is detrimental for learning, and that the behavioral state in which hippocampal theta activity dominates is beneficial for learning, at least before a well-learned state is achieved.  相似文献   
162.
The present study investigates the influence of preparation on inhibitory effects in cued task switching. In three experiments, we assessed n − 2 repetition costs as marker of inhibition of the just executed and now irrelevant task by comparing performance in task sequences such as ABA (i.e., n − 2 repetitions, with A, B and C standing for different tasks) to task sequences such as CBA (i.e., n − 2 switches). Specifically, we varied the cue–target interval (CTI) to examine cue-based preparation effects. In addition, we manipulated cue type (i.e., abstract, verbal, and direct cues) across the three experiments. We obtained significant reductions of n − 2 repetition costs with prolonged CTI when using abstract cues (i.e., coloured frames) and task names (i.e., digit), but not when using the task-specific stimulus–response mapping as cue for the upcoming task. These data suggest that cue-based preparation is not a uniform process but depends on the information provided by the cue.  相似文献   
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This study aimed to determine whether psychological factors associated with Post-Traumatic Stress Disorder (PTSD) identified in Western samples generalize to low Social-Economical-Status (SES) populations in an underdeveloped Asian country. The study included 113 survivors of the 2004-tsunami on the south coast of Sri Lanka, recruited from 4 preschools and 10 villages for displaced persons. With logistic regressions the relations between interview-based PTSD diagnosis and psychological factors were assessed, controlling for putative confounders. Fifteen months post-trauma the prevalence of PTSD was 52.2%. Multivariate analyses indicated that negative interpretation of tsunami-memories was significantly (P < 0.005) related to PTSD. Of the putative confounders, gender and (non-replaced) lost work equipment were related to current PTSD (P < 0.05). The results indicate that the relation between negative interpretation of trauma memories and PTSD is quite universal, suggesting that interventions focusing on this factor may be important in treatment of tsunami survivors who are suffering from chronic PTSD.  相似文献   
165.
Secondary or incidental results can be identified in genomic research that increasingly uses whole exome/genome sequencing. Understanding research participants’ preferences for secondary results and what influences these decisions is important for patient education, counseling, and consent, and for the development of policies regarding return of secondary results. Two hundred nineteen research participants enrolled in genomic studies were surveyed regarding hypothetical preferences for specific types of secondary results, and these preferences were correlated with demographic information and psychosocial data. The majority of research participants (73%) indicated a preference to learn about all results offered, with no clear pattern regarding which results were not desired by the remaining participants. Participants who reported greater interest in genetic privacy were less likely to indicate a preference to learn all results, as were individuals who self-identified as Jewish. Although most research participants preferred to receive all secondary results offered, a significant subset preferred to exclude some results, suggesting that an all-or-none policy would not be ideal for all participants. The correlations between preferences to receive secondary results, religious identification, and privacy concerns demonstrate the need for culturally sensitive counseling and educational materials accessible to all education levels to allow participants to make the best choices for themselves.  相似文献   
166.
Cognitive training in MCI may stimulate pre-existing neural reserves or recruit neural circuitry as “compensatory scaffolding” prompting neuroplastic reorganization to meet task demands (Reuter-Lorenz & Park, 2014). However, existing systematic reviews and meta-analytic studies exploring the benefits of cognitive interventions in MCI have been mixed. An updated examination regarding the efficacy of cognitive intervention in MCI is needed given improvements in adherence to MCI diagnostic criteria in subject selection, better defined interventions and strategies applied, increased use of neuropsychological measures pre- and post-intervention, as well as identification of moderator variables which may influence treatment. As such, this meta-analytic review was conducted to examine the efficacy of cognitive intervention in individuals diagnosed with mild cognitive impairment (MCI) versus MCI controls based on performance of neuropsychological outcome measures in randomized controlled trials (RCT). RCT studies published from January 1995 to June 2017 were obtained through source databases of MEDLINE-R, PubMed, Healthstar, Global Health, PSYCH-INFO, and Health and Psychological Instruments using search parameters for MCI diagnostic category (mild cognitive impairment, MCI, pre-Alzheimer’s disease, early cognitive decline, early onset Alzheimer’s disease, and preclinical Alzheimer’s disease) and the intervention or training conducted (intervention, training, stimulation, rehabilitation, or treatment). Other inclusion and exclusion criteria included subject selection based on established MCI criteria, RCT design in an outpatient setting, MCI controls (active or passive), and outcomes based on objective neuropsychological measures. From the 1199 abstracts identified, 26 articles met inclusion criteria for the meta-analyses completed across eleven (11) countries; 92.31% of which have been published within the past 7 years. A series of meta-analyses were performed to examine the effects of cognitive intervention by cognitive domain, type of training, and intervention content (cognitive domain targeted). We found significant, moderate effects for multicomponent training (Hedges’ g observed?=?0.398; CI [0.164, 0.631]; Z?=?3.337; p?=?0.001; Q?=?55.511; df?=?15; p?=?0.000; I 2 ?=?72.978%; τ 2 ?=?0.146) as well as multidomain-focused strategies (Hedges’ g?=?0.230; 95% CI [0.108, 0.352]; Z?=?3.692; p??< 0.001; Q?=?12.713; df?=?12; p?=?0.390; I 2 ?=?5.612; τ 2 ?=?0.003). The effects for other interventions explored by cognitive domain, training type, or intervention content were indeterminate due to concerns for heterogeneity, bias, and small cell sizes. In addition, subgroup and meta-regression analyses were conducted with the moderators of MCI category, mode of intervention, training type, intervention content, program duration (total hours), type of control group (active or passive), post-intervention follow-up assessment period, and control for repeat administration. We found significant overall effects for intervention content with memory focused interventions appearing to be more effective than multidomain approaches. There was no evidence of an influence on outcomes for the other covariates examined. Overall, these findings suggest individuals with MCI who received multicomponent training or interventions targeting multiple domains (including lifestyle changes) were apt to display an improvement on outcome measures of cognition post-intervention. As such, multicomponent and multidomain forms of intervention may prompt recruitment of alternate neural processes as well as support primary networks to meet task demands simultaneously. In addition, interventions with memory and multidomain forms of content appear to be particularly helpful, with memory-based approaches possibly being more effective than multidomain methods. Other factors, such as program duration, appear to have less of an influence on intervention outcomes. Given this, although the creation of new primary network paths appears strained in MCI, interventions with memory-based or multidomain forms of content may facilitate partial activation of compensatory scaffolding and neuroplastic reorganization. The positive benefit of memory-based strategies may also reflect transfer effects indicative of compensatory network activation and the multiple-pathways involved in memory processes. Limitations of this review are similar to other meta-analysis in MCI, including a modest number studies, small sample sizes, multiple forms of interventions and types of training applied (some overlapping), and, while greatly improved in our view, a large diversity of instruments used to measure outcome. This is apt to have contributed to the presence of heterogeneity and publication bias precluding a more definitive determination of the outcomes observed.  相似文献   
167.
To determine whether mildly and moderately dysphoric adolescent mothers display infantized facial and vocal behaviors, 21 nondysphoric mothers and 32 dysphoric (16 mildly and 16 moderately/severely dysphoric) mothers were videotaped during face-to-face interactions with their 4-month-old infants. Mildly dysphoric mothers showed less positive facial expressions and less animated/exaggerated vocal expressions. The moderately/severely dysphoric mothers, however, did not differ from nondysphoric mothers in their display of facial and vocal behaviors. These mothers with higher Beck Depression Inventory (BDI) scores may have become concerned about their many symptoms affecting their interactions and tried to compensate for this during their interactions. A second study was conducted to determine whether completing the BDI before interactions positively affected the moderately/severely dysphoric mothers' behavior. Moderately/severely dysphoric mothers (N=24) and mildly dysphoric mothers (N=24) were given the Beck Depression Inventory either before or after their face-to-face interactions with their 4-month-old infants. Moderately/severely dysphoric mothers who were given the BDI before their interactions showed more positive behavior than mothers given the BDI after their interactions. © 1997 Michigan Association for Infant Mental Health  相似文献   
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169.
Unassertive psychiatric patients matched on age, years of education, diagnosis, and self-reported assertiveness were assigned to one of five conditions, with 10 subjects in each group: (1) Test-Retest, (2) Practice-Control, (3) Instructions, (4) Modeling, (5) Modeling plus Instructions. All subjects were videotaped (Pre- and Post-Test) while responding to five interpersonal situations requiring assertive responses. Pre- and Post-Test responses for all subjects were rated independently by judges on seven verbal and non-verbal components of assertiveness. Analyses of variance for difference scores followed by multiple t-test comparisons indicated that the Modeling plus Instructions group was superior or equal to the Instructions alone or Modeling alone groups on five of the seven components. Instructions alone and Modeling alone led to greatest improvement in the remaining two components. No differences were found between the Practice-Control and Test-Retest groups on any of the seven components of assertiveness. No differences (Post-Pretest) were found among the groups on a self-report measure of assertiveness.  相似文献   
170.
Members of higher status groups generalize characteristics of their ingroup to superordinate categories that serve as a frame of reference for comparisons with outgroups (ingroup projection). We propose that the causal process depends on the security of the intergroup context: When intergroup relations are secure, projection derives from a motivation to represent the superordinate category efficiently; when they are insecure, projection is a defense motivated process. Accordingly, we hypothesized that inducing participants to use heuristic vs. systematic information processing (via time pressure, cognitive load, or thoughtfulness instructions) would have differential effects on ingroup projection in secure as compared to insecure intergroup relations. Three experiments manipulated security of the intergroup context and information processing mode in artificial (Studies 1 and 2) or natural (Study 3) groups. We found that time pressure increased ingroup projection in the secure-group condition but decreased it in the insecure-group condition (Study 1), cognitive load increased projection in the secure but not in the insecure condition (Study 2) and thoughtfulness instructions increased projection for high identifiers in the insecure but not in the secure condition (Study 3). Results support the hypothesis that ingroup projection occurs as a cognitive bias in secure intergroup relations but that it is socially motivated by the specific intergroup relation when this relation is insecure.  相似文献   
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