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781.
Sylvie Naar-King Deborah Ellis Karen Kolmodin Phillippe Cunningham Elizabeth Secord 《Journal of child and family studies》2009,18(5):564-573
African-American adolescents have the highest rates of asthma morbidity and mortality, yet there are few successful behavioral
interventions to improve illness management for this group. Mental health providers have an opportunity to expand their services
and impact by targeting adolescents with poor asthma management. We describe the adaptation of Multisystemic Therapy (MST),
an intensive, home and community-based treatment originally used with antisocial youth, for improving asthma management. We
present a case study to illustrate the treatment model. Feasibility was demonstrated with eight African American adolescents
with chronic, persistent asthma, suggesting that further evaluation of MST for youth with asthma and poor illness management
is warranted. 相似文献
782.
Jonathan B. Kelley Mara A. Balda Karen L. Anderson Yossef Itzhak 《Learning & memory (Cold Spring Harbor, N.Y.)》2009,16(6):371-378
The fear conditioning paradigm is used to investigate the roles of various genes, neurotransmitters, and substrates in the formation of fear learning related to contextual and auditory cues. In the brain, nitric oxide (NO) produced by neuronal nitric oxide synthase (nNOS) functions as a retrograde neuronal messenger that facilitates synaptic plasticity, including the late phase of long-term potentiation (LTP) and formation of long-term memory (LTM). Evidence has implicated NO signaling in synaptic plasticity and LTM formation following fear conditioning, yet little is known about the role of the nNOS gene in fear learning. Using knockout (KO) mice with targeted mutation of the nNOS gene and their wild-type (WT) counterparts, the role of NO signaling in fear conditioning was investigated. Plasma levels of the stress hormone corticosterone were measured to determine the relationship between physiological and behavioral response to fear conditioning. Contextual fear learning was severely impaired in male and female nNOS KO mice compared with WT counterparts; cued fear learning was slightly impaired in nNOS KO mice. Sex-dependent differences in both contextual and cued fear learning were not observed in either genotype. Deficits in contextual fear learning in nNOS KO mice were partially overcome by multiple trainings. A relationship between increase in plasma corticosterone levels following footshock administration and the magnitude of contextual, but not cued freezing was also observed. Results suggest that the nNOS gene contributes more to optimal contextual fear learning than to cued fear learning, and therefore, inhibition of the nNOS enzyme may ameliorate context-dependent fear response.Anxiety disorders, such as post-traumatic stress disorder (PTSD), constitute the most prevalent mental illnesses in the United States, costing nearly one-third of the country''s total health bill (Greenberg et al. 1999). The treatment of these disorders requires overcoming complications such as reluctance to seek mental health treatment and an extremely high comorbidity rate with other affective disorders, reaching 80% (Brady 1997; Solomon and Davidson 1997). Emerging evidence suggests that dysfunctions underlying acquired anxiety and PTSD include an abnormal reaction to stress, which is mediated by specific neurochemical and neuroanatomical substrates (Yehuda and McFarlane 1995; Adamec 1997). Pharmacotherapies that target neuronal signaling molecules, such as nitric oxide (NO), may play a role in the treatment of these disorders.In the brain, N-methyl-d-aspartate receptor (NMDAR) activation and calcium influx into the cell activates the neuronal nitric oxide synthase (nNOS) enzyme to produce NO, which has the role of retrograde messenger (Snyder 1992). NO is involved in memory formation and synaptic plastic events such as late-phase long-term potentiation (LTP) (Lu et al. 1999; Arancio et al. 2001; Puzzo et al. 2006). Behavioral evidence in invertebrates (Lewin and Walters 1999; Muller 2000; Kemenes et al. 2002; Matsumoto et al. 2006) and vertebrates (Medina and Izquierdo 1995; Rickard et al. 1998; Ota et al. 2008) suggest that NO has a major role in consolidation of long-term memory (LTM). Recently, studies have shown that site-specific pharmacological blockade of NO signaling in rats impairs contextual (Resstel et al. 2008) and cued (Schafe et al. 2005) fear learning. However, the role of the nNOS gene in fear conditioning has not been investigated.In the present study, fear conditioning was investigated in homozygous nNOS knockout (KO) and wild-type (WT) mice. In the fear-conditioning paradigm, the association of a footshock (unconditioned stimulus; US), with a specific context and a neutral stimulus (auditory cue) results in learned fear. Re-exposure to the conditioning context and to the previously neutral auditory cue (conditioned stimulus; CS) elicits a freezing response in the absence of the aversive US. Thus, the fear-conditioning paradigm includes both contextual and cued fear learning components, which can be measured in separate tests. Fear conditioning recruits both the amygdala (emotional cue learning) and the hippocampus (spatial/contextual learning) (Phillips and LeDoux 1992; Goosens and Maren 2004; Mei et al. 2005). The involvement of these brain regions in fear learning and anxiety has been confirmed by animal and human imaging studies (LeDoux 1998; Rauch et al. 2006).We report that nNOS KO mice showed a severe deficiency in contextual fear learning and a less marked deficit in cued fear learning compared with WT mice after a single fear-conditioning session. This deficiency was partially improved by multiple (four) fear-conditioning sessions. In addition, we observed that plasma levels of corticosterone, the primary stress hormone in rodents, are related to contextual fear learning ability. 相似文献
783.
784.
Matthew Porritt Karen Van Wagner Alan Poling 《Journal of applied behavior analysis》2009,42(2):295-307
Pigeons were exposed to a repeated acquisition procedure in which no delays were imposed and rate of responding was relatively high. They also were exposed to conditions in which delays were arranged between trials within chains or between completed chains, and rates of responding were lower. Number of trials, rate of reinforcement, difficulty of the discrimination, and motivating operations were held constant. Terminal accuracy was highest under the no‐delay condition, in which rate of responding was highest. Effects of trial spacing on retention were mixed and depended on whether delays were imposed between trials within chains or between completed chains. These findings provide basic‐research support for the rapid presentation of trials in direct instruction and for rate building in precision teaching. 相似文献
785.
Maggie E. Toplak Ashley Pitch David B. Flora Linda Iwenofu Karen Ghelani Umesh Jain Rosemary Tannock 《Journal of abnormal child psychology》2009,37(8):1137-1150
To examine the unity and diversity of inattention and hyperactivity/impulsivity symptom domains of Attention-Deficit/Hyperactivity
Disorder (ADHD) in a clinical sample of adolescents with ADHD. Parents and adolescents were administered a semi-structured
diagnostic interview, the Schedule for Affective Disorders and Schizophrenia for School-Age Children — Present and Lifetime
Version (K-SADS-PL), to assess adolescent ADHD. Data from 201 parent interviews and 189 adolescent interviews were examined.
Four potential factor structures for the 18 ADHD symptoms were tested using confirmatory factor analysis: two models with
correlated factors and two bifactor models. A bifactor model with two specific factors best accounted for adolescent symptoms,
according to both parent and adolescents’ reports. Replication of these findings from behavioral rating scales completed for
this sample by parents and teachers indicates that the findings are not method– or informant-specific. The results suggest
that there is an important unitary component to ADHD symptoms and separable dimensional traits of Inattention and Hyperactivity/Impulsivity. 相似文献
786.
Instead of assessing activation in distinct brain regions, approaches to investigating the networks underlying distinct brain functions have come into the focus of neuroscience research. Here, we provide a completely data-driven framework for assessing functional and causal connectivity in functional magnetic resonance imaging (fMRI) data, employing Granger's causality. We investigate the networks underlying story processing in 17 healthy children (8f, 9m, 10.4+/-2.8 years, 6.5-15.4 years). Extensive functional connectivity exists between brain regions, including some not detected in standard random effects analyses. Causal connectivity analyses demonstrate a clear dominance of left-sided language regions for both forward and backward interactions with other network nodes. We believe our approach to be useful in helping to assess language networks in the normal or pathological setting; it may also aid in providing better starting estimates for the more hypothesis-driven approaches like structural equation or dynamic causal modeling. 相似文献
787.
Karen Ostrov Jerome Dowling David O. Wesner Frank K. Johnson 《Infant mental health journal》1982,3(3):162-173
Infant psychotherapy, in which the mother is requested to follow the baby's activities without initiating or directing, is described. Mothers demonstrate different styles of involvement with their infants: a protective mode, a prohibitive mode, a competitive mode, and other ways of interfering with their infants' tendency to explore the environment. Attempts to analyze such factors as position, distance and movement are discussed. Research for recording and analyzing the movement of infant and mother dyads is proposed. 相似文献
788.
789.
Several theories consider the development of short-term memory (STM) in children to reflect the development of processing operations. This article reports an experiment that tested some of these theories, using a release from proactive interference (PI) procedure in conjunction with a running memory task, to track down age-related improvements in the processing of various kinds of information. Although evidence for the development of PI release with age appeared for two kinds of information, namely class of item and acoustic similarity, there was no evidence whatsoever for the existence of a relationship between STM performance and PI release. It was concluded that the development of STM on the one hand, and of the capacity to process item or acoustic information on the other, proceed independently of each other. The discussion deals with the apparent conflict between this conclusion and the theoretical positions. 相似文献
790.