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281.
A scale to measure attitudes towards seeking psychological help was developed (Beliefs About Psychological Services [BAPS]) and evaluated. This scale was based on items gathered from students, colleagues, and the authors when asked about common positive and negative attitudes toward psychologists and their services. Items were also based on the Fischer and Turner (1970) Attitudes Toward Seeking Professional Psychological Services (ATSPPH) measure. Three studies are reported describing the construction and evaluation of the psychometric properties of the BAPS. The BAPS is an 18-item measure consisting of three subscales: Intent, Stigma Tolerance, and Expertness. Support was found for the reliability and validity of the measure. 相似文献
282.
LTP in hippocampal area CA1 is induced by burst stimulation over a broad frequency range centered around delta 下载免费PDF全文
Lawrence M. Grover Eunyoung Kim Jennifer D. Cooke William R. Holmes 《Learning & memory (Cold Spring Harbor, N.Y.)》2009,16(1):69-81
Long-term potentiation (LTP) is typically studied using either continuous high-frequency stimulation or theta burst stimulation. Previous studies emphasized the physiological relevance of theta frequency; however, synchronized hippocampal activity occurs over a broader frequency range. We therefore tested burst stimulation at intervals from 100 msec to 20 sec (10 Hz to 0.05 Hz). LTP at Schaffer collateral–CA1 synapses was obtained at intervals from 100 msec to 5 sec, with maximal LTP at 350–500 msec (2–3 Hz, delta frequency). In addition, a short-duration potentiation was present over the entire range of burst intervals. We found that N-methyl-d-aspartic acid (NMDA) receptors were more important for LTP induction by burst stimulation, but L-type calcium channels were more important for LTP induction by continuous high-frequency stimulation. NMDA receptors were even more critical for short-duration potentiation than they were for LTP. We also compared repeated burst stimulation with a single primed burst. In contrast to results from repeated burst stimulation, primed burst potentiation was greater when a 200-msec interval (theta frequency) was used, and a 500-msec interval was ineffective. Whole-cell recordings of postsynaptic membrane potential during burst stimulation revealed two factors that may determine the interval dependence of LTP. First, excitatory postsynaptic potentials facilitated across bursts at 500-msec intervals but not 200-msec or 1-sec intervals. Second, synaptic inhibition was suppressed by burst stimulation at intervals between 200 msec and 1 sec. Our data show that CA1 synapses are more broadly tuned for potentiation than previously appreciated.Long-term potentiation (LTP) is used as a model for studying synaptic events during learning and memory (Bliss and Collingridge 1993; Morris 2003; Lynch 2004). At most synapses, LTP is triggered by postsynaptic Ca2+ influx through N-methyl-d-aspartic acid (NMDA) glutamate receptors (Collingridge et al. 1983; Harris et al. 1984; Herron et al. 1986) and, under some conditions, through L-type voltage-gated Ca2+ channels (Grover and Teyler 1990, 1994; Morgan and Teyler 1999). LTP was discovered in the dentate gyrus (Bliss and Lomo 1973) following several seconds of 10–100 Hz stimulation of the perforant path. Since then, many LTP studies have used similar long, high-frequency stimulation (HFS) protocols, most typically 100 Hz, 1 sec (Bliss and Collingridge 1993). Although effective, HFS does not resemble physiological patterns of activity (Albensi et al. 2007). Patterned stimulation resembling physiological activity, in particular theta burst stimulation, is also effective for LTP induction (Larson et al. 1986; Staubli and Lynch 1987; Capocchi et al. 1992; Nguyen and Kandel 1997). Theta burst stimulation consists of short bursts (4–5 stimuli at 100 Hz) repeated at 5 Hz, which lies within the hippocampal theta frequency range (4–12 Hz) (Bland 1986; Buzsáki 2002). Primed burst stimulation, another form of patterned stimulation, involves delivery of a priming stimulus followed by a single short burst (Larson and Lynch 1986; Rose and Dunwiddie 1986). The temporal requirements for primed burst LTP are quite precise (Diamond et al. 1988; Greenstein et al. 1988; Larson and Lynch 1989): Intervals less than 140 msec or greater than 200 msec are ineffective.The mechanisms underlying theta frequency-dependent LTP have been studied primarily using the primed burst protocol (Larson and Lynch 1986, 1988, 1989; Pacelli et al. 1989; Davies and Collingridge 1996). Activation of GABAB autoreceptors during the priming stimulus suppresses GABA release during the following burst (Davies et al. 1990; Lambert and Wilson 1994; Olpe et al. 1994), allowing greater postsynaptic depolarization (Larson and Lynch 1986; Pacelli et al. 1989) and more effective NMDA receptor activation (Davies and Collingridge 1996). Consequently, temporal requirements for primed burst potentiation match the time course of GABAB autoreceptor-mediated suppression of GABA release (Davies et al. 1990; Davies and Collingridge 1993; Mott et al. 1993).Besides theta, hippocampal activity is observed at other frequencies, notably sharp waves (0.01–5 Hz) (Buzsáki 1986, 1989; Suzuki and Smith 1987) and low-frequency oscillations (≤1 Hz) (Wolansky et al. 2006; Moroni et al. 2007). These lower frequencies dominate during slow wave sleep (Buzsáki 1986; Suzuki and Smith 1987; Wolansky et al. 2006; Moroni et al. 2007), and contribute to hippocampal memory processing (Buzsáki 1989; Pennartz et al. 2002). While synchronized population activity over frequencies from <1 Hz to 12 Hz is associated with hippocampal memory function, previous LTP studies have focused on theta. We therefore investigated burst stimulation at frequencies from 0.05 Hz to 10 Hz. We found that CA1 synapses potentiate to some degree over this entire range and that maximal potentiation occurs around delta frequency rather than theta. 相似文献
283.
Understanding the negative effects of legal education on law students: a longitudinal test of self-determination theory 总被引:2,自引:0,他引:2
Longitudinal studies suggest that law school has a corrosive effect on the well-being, values, and motivation of students, ostensibly because of its problematic institutional culture. In a 3-year study of two different law schools, the authors applied self-determination theory's (SDT) dynamic process model of thriving to explain such findings. Students at both schools declined in psychological need satisfaction and well-being over the 3 years. However, student reports of greater perceived autonomy support by faculty predicted less radical declines in need satisfaction, which in turn predicted better well-being in the 3rd year and also a higher grade point average, better bar exam results, and more self-determined motivation for the first job after graduation. Institution-level analyses showed that although students at both schools suffered, one school was perceived as more controlling than the other, predicting greater difficulties for its students. Implications for SDT and for legal education are discussed. 相似文献
284.
Janet S. St. Lawrence Tracey E. Wilson Gloria D. Eldridge Ted L. Brasfield Robert E. O'Bannon III 《American journal of community psychology》2001,29(6):937-964
A community-based sample of disadvantaged African American women (n = 445) was recruited to participate in 1 of 3 theoretically driven experimental interventions based on either the theory of gender and power, social learning theory, or cognitive behavioral theory. Intervention outcomes were compared with a waiting list control condition. From baseline to postintervention, women in the experimental interventions showed differential change on cognitive indices (knowledge and attitudes) and skill acquisition (partner negotiation skills, correct condom application, lubricant selection, and information-provision to social networks) whereas control participants were unchanged. Women in the 3 experimental interventions also completed follow-up assessments for 1 year following the interventions. In all 3 experimental conditions, condom use increased relative to the control group and there were no differences between the experimental interventions. Women who participated in one of the theoretically grounded interventions continued to increase condom use over the following year. Women entering new relationships reported significantly more condom use than did women who remained in ongoing relationships. The findings suggest that intervention models that have proven effective for women who engage in high-risk behavior may be less effective for women in established relationships for whom risk is primarily derived from the extrarelationship behavior of their partners. 相似文献
285.
S. Ratneshwar Lawrence W. Barsalou Cornelia Pechmann Melissa Moore 《Journal of Consumer Psychology》2001,10(3):147-157
Prior research often emphasized a stimulus‐based or bottom‐up view of product category representations. In contrast, we emphasize a more purposeful, top‐down perspective and examine categories that consumers might construct in the service of salient (i.e., highly accessible) goals. Specifically, we investigate how the point of view imposed by salient consumer goals might affect category representations assessed by participants’ similarity judgments of food products. A key factor in our study is that we examine both individual and situational sources of variability in goal salience. In addition, we also vary the surface‐level, visual resemblance of the stimulus pairs of foods used in the study. The results suggest that personal goals (e.g., health) and situational goals (e.g., convenience) act in conjunction and exert a systematic impact on category representations. Both types of goals, when salient, enhanced the perceived similarity of goal‐appropriate products and reduced the similarity of product pairs when only one product was ideal for the particular goal. The similarity‐enhancing effect was most pronounced when the surface resemblance between the products was low, and the similarity‐diminishing effect was more apparent when surface resemblance was high. Implications are discussed for current theoretical assumptions regarding categorization in consumer research. 相似文献
286.
Lawrence Josephs 《The International journal of psycho-analysis》2001,82(4):701-712
The author describes a pathological manifestation of the approving superego that functions as a perversely seductive superego. In this process, the seductive superego rationalises and makes ego-syntonic a gratification of forbidden wishes that will result in unconscious punishment. The author argues that the seductive superego torments the self by teasing it with the presence of a tantalising but forbidden object of desire and then by inflicting shame on the self for its timidity, which prevents it from pursuing the object in spite of the dangers. He suggests that the seductive superego inflicts a betrayal trauma upon the self by unconsciously actualising a sado-masochistic fantasy of seduction, surrender and betrayal, along with a humiliating punishment for surrendering. 相似文献
287.
Synesthesia: Strong and Weak 总被引:2,自引:0,他引:2
In this review, we distinguish strong and weak forms of synesthesia. Strong synesthesia is characterized by a vivid image in one sensory modality in response to stimulation in another one. Weak synesthesia is characterized by cross-sensory correspondences expressed through language, perceptual similarity, and perceptual interactions during information processing. Despite important phenomenological dissimilarities between strong and weak synesthesia, we maintain that the two forms draw on similar underlying mechanisms. The study of strong and weak synesthetic phenomena provides an opportunity to enrich scientists' understanding of basic mechanisms involved in perceptual coding and cross-modal information processing. 相似文献
288.
Thomas P. Pallmeyer Edward B. Blanchard Lawrence C. Kolb 《Behaviour research and therapy》1986,24(6):645-652
The psychophysiological responses of heart rate (HR), systolic and diastolic blood pressure, skin conductance level and forehead electromyogram were compared during: rest, mental arithmetic and combat sounds of gradually increasing intensity for five groups of Ss: Vietnam veterans with post-traumatic stress disorder (PTSD); Vietnam veterans without PTSD but with comparable levels of combat experience; Vietnam veterans with other psychiatric disorders; Vietnam-era veterans; and nonveteran phobics. HR response to low-intensity combat sounds provided good discrimination between veterans with PTSD and the other groups and seems to resemble a conditioned emotional response. 相似文献
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290.