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111.
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This prospective cohort study used administrative data from the Army Study to Assess Risk and Resilience in Servicemembers to examine associations between neurocognitive functioning and subsequent suicidal events among Regular Army enlisted soldiers during the years 2004–2009. Cases were all soldiers who completed the Army's Automated Neuropsychological Assessment Metrics (ANAM) computerized testing battery prior to documented suicide attempt (n = 607), ideation (n = 955), or death (n = 57). Controls were an equal‐probability sample of 9,893 person‐months from other soldiers. Exploratory factor analysis of five ANAM tests identified a general neurocognitive factor that excluded the mathematic processing test (MTH). When examined separately in logistic regression analyses that controlled for sociodemographics and prior mental health diagnosis, both the general neurocognitive factor (logit [β] = ?.197 to ?.521; < .01) and MTH (β = ?.024 to ?.064; < .05) were associated with all outcomes. When both predictors were examined simultaneously, the general neurocognitive factor continued to be associated with all outcomes (β = ?.164 to ?.417; < .05) and MTH continued to be associated with suicide attempt (β = ?.015; = .046) and ideation (β = ?.014; = .018). These small but robust associations suggest that future research must continue to examine the extent to which objective neurocognitive tests may enhance understanding and prediction of suicide risk.  相似文献   
113.
The purpose of the present research was to examine the influence of cognitive processes on discourse global coherence ability measured across different discourse tasks and collected from younger (n = 40; 20–39 years) and older (n = 40; 70–87 years) cognitively healthy adults. Study participants produced oral language samples in response to five commonly used discourse elicitation tasks and they were analyzed for maintenance of global coherence. Participants also completed memory and attention measures. Group differences on the global coherence scale were found for only one type of discourse—recounts. Across discourse elicitation tasks the lowest global coherence scores were found for recounts compared to the other discourse elicitation tasks. The influence of cognitive processes on maintenance of global coherence differed for the two age groups. For the younger group, there were no observed significant relationships. For the older group, cognitive measures were related to global coherence of stories and procedures.  相似文献   
114.
The current study is a pilot evaluation of a six-week psychoeducational-support group based in an ambiguous loss framework for family members of people who hoard. Findings suggest that participants who completed the six-week intervention group (N?=?8) indicated positive results at the two-month follow up interview, reporting an increased understanding of family members’ hoarding behaviors and their own experiences related to the hoarding behavior and its impact on the family system. Participants also reported that having personal and professional support from others who understand hoarding behavior was helpful to them in lowering psychological distress and improving interactions with their family members.  相似文献   
115.
Six pigeons key-pecked under a fixed-interval (FI) 3-min schedule of food presentation. Each pigeon was studied for 200 daily sessions with 15 intervals per session (3,000 total food presentations). Analyses included the examination of latency to first peck (pause), mean rate of key pecking, and ambulation. Characterizations of stable performance were assessed across measures of behavior and evaluated using commonly employed stability criteria. Stability of response rate and pause was identified better by assessments that evaluated variability and trend, rather than just variability. Between-subject differences in rate of acquisition and terminal values of steady-state performance of pause were observed, and stable pause durations took longer to develop than did stable key-pecking rates. Relative variability in response rate and pause duration decreased as the means increased. A temporally organized pattern of key-pecking (the so-called FI scallop) developed within 50 sessions of exposure to the schedule. Overall ambulation decreased during the early sessions of exposure and further analyses showed greater rates of ambulation during the pause than after it for 4 of the 6 pigeons. Performance under the FI 3-min schedule developed relatively slowly, and key-pecking, pause, and ambulation developed at different rates.  相似文献   
116.
Domestic hens responded under multiple fixed‐ratio fixed‐ratio schedules with equal fixed ratios. One component provided immediate reinforcement and the other provided reinforcement after a delay, signaled by the offset of the key light. The components were presented quasirandomly so that all four possible transitions occurred in each session. The delay was varied over 0, 4, 8, 16, and 32 s with fixed‐ratio 5 schedules, and over 0, 8 and 32 s with fixed‐ratio 1, 15 and 40 schedules. Main effects of fixed‐ratio value and delay duration were detected on between‐ratio pauses. Pauses were longer when the multiple‐schedule stimulus correlated with a delayed‐reinforcer component was presented, with the longest pauses occurring at the transition from a component with an immediate reinforcer to one with a delayed reinforcer. Pause durations were shortest during immediate components. Overall, both the presence or absence of a delay in the upcoming component, and the presence or absence of a delay in the preceding component affected pause length, but the upcoming delay had the larger effect. Thus changes in delay had similar effects to past reports of the effects of changes in response force, response requirement, and reinforcer magnitude in multiple fixed‐ratio fixed‐ratio schedules.  相似文献   
117.
This study examined the relations of dysregulated negative emotional reactivity, emotional distress, and chronic peer victimization in childhood. A model was proposed whereby dysregulated reactivity was directly and indirectly related to concurrent peer victimization through victimization‐related emotional distress. The model further proposed that dysregulated reactivity directly incrementally predicted longitudinal peer victimization above and beyond the effect of concurrent victimization. Two hundred thirteen 9‐ to 13‐year‐old children and their parents completed measures of dysregulated reactivity and victimization experiences at baseline and 6‐month follow‐up. Children also related narratives of personal victimization experiences at baseline that were coded to assess victimization‐related emotional distress. Model testing strongly supported the direct association of dysregulated reactivity with concurrent victimization and incremental predictive effects of dysregulated reactivity on peer victimization over time. Model testing also provided support for an indirect effect of dysregulated reactivity on concurrent peer victimization through victimization‐related emotional distress. This study demonstrated the powerful role that dysregulated negative emotional reactivity plays in the development of chronic peer victimization over time. Aggr. Behav. 38:414‐427, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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119.
Evidence suggests that parental marital discord contributes to the development of internalizing and externalizing symptoms in children and adolescents. Few studies, however, have examined the association between parental marital discord and youth’s response to treatment. The present study examined the impact of interparental discord on treatment response in a randomized control trial of adolescents with major depression enrolled in the Treatment for Adolescents with Depression Study (TADS). Participants were 260 adolescents from two-parent households randomly assigned to one of four treatment groups: fluoxetine (FLX), cognitive behavior therapy (CBT), their combination (COMB), or placebo (PBO). Logistic regressions revealed that parental marital discord interacted with youth gender and co-morbid oppositionality symptoms to predict group differences in treatment response.  相似文献   
120.
When conditioning involves a consistent temporal relationship between the conditioned stimulus (CS) and unconditioned stimulus (US), the expression of conditioned responses within a trial peaks at the usual time of the US relative to the CS. Here we examine the temporal profile of responses during conditioning with variable CS-US intervals. We conditioned stimuli with either uniformly distributed or exponentially distributed random CS-US intervals. In the former case, the frequency of each CS-US interval within a specified range is uniform but the momentary probability of the US (the hazard function) increases as time elapses during the trial; with the latter distribution, short CS-US intervals are more frequent than longer intervals, but the momentary probability of the US is constant across time within the trial. We report that, in a magazine approach paradigm, rats' response rates remained stable as time elapses during the CS when the CS-US intervals were uniformly distributed, whereas their response rates declined when the CS-US intervals were exponentially distributed. In other words, the profile of responding during the CS matched the frequency distribution of the US times, not the momentary probability of the US during the CS. These results are inconsistent with real-time associative models, which predict that associative strength tracks the momentary probability of the US, but may provide support for timing models of conditioning in which conditioned responding is tied to remembered times of reinforcement.  相似文献   
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