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White JA McKinney BC John MC Powers PA Kamp TJ Murphy GG 《Learning & memory (Cold Spring Harbor, N.Y.)》2008,15(1):1-5
To determine whether L-type voltage-gated calcium channels (L-VGCCs) are required for remote memory consolidation, we generated conditional knockout mice in which the L-VGCC isoform Ca(V)1.2 was postnatally deleted in the hippocampus and cortex. In the Morris water maze, both Ca(V)1.2 conditional knockout mice (Ca(V)1.2(cKO)) and control littermates displayed a marked decrease in escape latencies and performed equally well on probe trials administered during training. In distinct contrast to their performance during training, Ca(V)1.2(cKO) mice exhibited significant impairments in spatial memory when examined 30 d after training, suggesting that Ca(V)1.2 plays a critical role in consolidation of remote spatial memories. 相似文献
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Patricia Frazier Howard Tennen Margaret Gavian Crystal Park Patricia Tomich Ty Tashiro 《Psychological science》2009,20(7):912-919
ABSTRACT— In this study, we evaluated the validity of self-reported posttraumatic growth (PTG) by assessing the relation between perceived growth and actual growth from pre- to posttrauma. Undergraduate students completed measures tapping typical PTG domains at Time 1 and Time 2 (2 months later). We compared change in those measures with scores on the Posttraumatic Growth Inventory (PTGI; Tedeschi & Calhoun, 1996 ) for those participants who reported a traumatic event between Time 1 and Time 2 ( n = 122). PTGI scores generally were unrelated to actual growth in PTG-related domains. Moreover, perceived growth was associated with increased distress from pre- to posttrauma, whereas actual growth was related to decreased distress, a pattern suggesting that perceived and actual growth reflect different processes. Finally, perceived (but not actual) growth was related to positive reinterpretation coping. Thus, the PTGI, and perhaps other retrospective measures, does not appear to measure actual pre- to posttrauma change. 相似文献
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Byrne JE Stergiou N Blanke D Houser JJ Kurz MJ Hageman PA 《Perceptual and motor skills》2002,94(1):265-280
This study investigated intralimb coordination during walking in young and elderly women using the theoretical model of dynamical systems. 20 women, 10 Young (M age=24.6 yr., SD= 3.2 yr.) and 10 Elderly (M age=73.7 yr., SD=4.9 yr.), were videotaped during free speed gait and gait perturbed by an ankle weight. Two parameters, one describing the phasing relationship between segments (mean absolute relative phase) and the other the variability of this relationship (deviation in phase), were calculated from the kinematics. Two-way analysis of variance (age and weight) with repeated measures on weight indicated that during the braking period the weight increased the mean absolute relative phase between the shank and the thigh and decreased it between the foot and the shank. The Elderly women had significant smaller values for the mean absolute relative phase between the shank and the thigh during the braking period. For the same period, deviation in phase increased for the segmental 'relationship between the shank and the thigh. The findings suggest that changes in intralimb coordination take place with asymmetrical weighting and the aging process. These changes are most clearly present during the braking period. 相似文献
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Traditionally, African Americans have registered lower rates of suicide than other ethnic groups. In the last 20 years this pattern has changed, particularly among young African Americans. To date, the research conducted regarding this phenomenon has been limited for a variety of reasons and previous research has been inconclusive in determining risk factors of African American suicide. The purpose of this paper is to identify risk and protective factors specific to African American suicide. To determine the factors, the 1993 National Mortality Follow-back Survey was analyzed. The risk factors identified include being under age 35, southern and northeastern residence, cocaine use, firearm presence in home, and threatening others with violence. Some of the protective factors associated with African American suicide include rural residence and educational attainment. These results provide valuable information about completed African American suicides in relation to Whites. Several of these factors are unique to African Americans. 相似文献
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Prior research has linked content analysis drawn from text narratives to psychopathology in trauma survivors. This study used a longitudinal design to determine whether linguistic elements of narrative memories of first hearing about the events of 11 September 2001 predict later post‐traumatic stress disorder (PTSD). Narratives and self‐report PTSD symptoms were collected within 1 week and again 5 months after 9/11 in 40 undergraduates. People who used more “we” words at Time 1 had fewer acute PTSD symptoms. Use of more cognitive mechanism words, more religion words, more first‐person singular pronouns, and fewer anxiety words at Time 1 were related to more chronic PTSD symptoms. Linguistic characteristics accounted for variance in chronic PTSD symptoms above and beyond acute PTSD symptoms. This study provides evidence that lasting PTSD symptoms can be predicted through language in the immediate aftermath of the trauma. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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