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251.
A primary prevention program, the Houston Parent-Child Development Center, directed towards infants and their parents, has effectively reduced the frequency of behavior problems for these children 5 to 8 years after the program's completion. Teacher ratings showed significantly fewer acting-out, aggressive behaviors for program children. Ratings of classroom behaviors found program children significantly less hostile and more considerate than control boys. This appears to be the first primary prevention program to have demonstrated effectiveness in reducing behavior problems over such a long time.  相似文献   
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253.
Stimulus generalization was investigated using institutionalized human retardates as subjects. A baseline was established in which two values along the stimulus dimension of auditory frequency differentially controlled responding on two bars. The insertion of the test probes disrupted the control established to the two SDs during training. The discrimination was recovered between each test probe and the resulting gradients were stable across 10 test sessions. These gradients, supported by other two-response generalization studies, indicate that this type of two-response discrimination training divides the stimulus dimension into two functional classes separated by a region of transition from one class to the other. Each stimulus value in a class, which extends from an SD outward to the functional limit of the dimension, controls a similar proportion of the two responses as each other value in the class. All values on the stimulus dimension control identical response rates with an absence of the usual generalization decrement. The latency of the initial response, however, shows a bimodal gradient with the modes at the SD values.  相似文献   
254.
The state-dependent theory of the relationship between affective states and memory holds that recall will be best when the affective state at recall matches that during learning. Sequential happy, neutral, and sad affective states that were either consistent (e.g., Happy-Happy) or inconsistent (e.g., Sad-Neutral) were experimentally induced in preschool children prior to encoding and then again prior to retrieval (free and cued recall, recognition memory). Facial ratings indicated that the inductions were effective in inducing affect. Nevertheless, emotional states did not influence children's ability to recall items under free or cued conditions, and recognition memory was essentially perfect for all subjects. Thus, there was no evidence for state-dependent learning or for a positive loop between subjects' positive affect at retrieval and memory for positively rated information. Results are discussed in terms of the generally inconsistent findings in the literature on the role of affect in children's memory and factors that may limit affective state-dependent learning in children.This research was supported by Research Grant No. 11776 from the National Institute of Child Health and Human Development to Marion Perlmutter, by Grant BNS 78-01108 from the National Science Foundation to John C. Masters, and by Program Project Grant No. 0527 to the Institute of Child Development. Wayne Duncan is now at the University of Denver, and Christine Todd is now at the University of Illinois, Urbana. Marion Perlmutter is now at the University of Michigan. We would like to thank Keith Elliott and LuAnne Tczap for their work as experimenters; Jule Kogan, Carol Revermann, and Sonya Hernandez for their help in coding data; and Jayne Grady-Reitan for her administrative assistance throughout the study.  相似文献   
255.
In two experiments, pigeons were trained on a recognition memory task, which required them to refrain from responding to a picture seen earlier that day. They learned this discrimination without detectable reliance on cues relating to the sequence of positive and negative trials. In both experiments, performance was significantly better when the same restricted set of stimuli was used each day than when an entirely novel set of stimuli was used each day, and in the former case there was less evidence of any significant decline in performance with increases in the interval between first and second presentations of a stimulus. The results suggest a powerful perceptual learning effect.  相似文献   
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257.
ABSTRACT

A child’s state of emotional dysregulation is often the explicit complaint of parents, teachers, and others involved in child referrals. Psychoanalytic and, more recently, neuropsychoanalytic thinking along with attachment research have created a foundation for understanding the biological and relational development of parent and child emotional engagement. In particular, these perspectives have clarified the nature of what Donald Winnicott termed impingements on the potential space between parent and child. An important addition to the understanding of biological and relational impingements on parent-child emotional dynamics comes from the field of occupational therapy (OT), which views sensory-motor regulatory capacities as forming the basis for quality relating and engaging. From an OT perspective, impingements on relating and adaptive functioning result from compromised regulation of arousal, affect, attention, and activity level on the part of the child, the parent, and/or the child/parent “fit.” Sensory integration and sensory processing theories offer additional frameworks for understanding and communicating with parents about patterns of mutual dysregulation in the parent-child relationship. When integrated with psychodynamic formulations, these ideas from OT research and practice can provide parents with new, more effective and flexible narratives of their children’s inner lives and behavior, and of their own narratives as parents.  相似文献   
258.
Mind wandering (i.e. engaging in cognitions unrelated to the current demands of the external environment) reflects the cyclic activity of two core processes: the capacity to disengage attention from perception (known as perceptual decoupling) and the ability to take explicit note of the current contents of consciousness (known as meta-awareness). Research on perceptual decoupling demonstrates that mental events that arise without any external precedent (known as stimulus independent thoughts) often interfere with the online processing of sensory information. Findings regarding meta-awareness reveal that the mind is only intermittently aware of engaging in mind wandering. These basic aspects of mind wandering are considered with respect to the activity of the default network, the role of executive processes, the contributions of meta-awareness and the functionality of mind wandering.  相似文献   
259.
A variety of visual mental imagery tasks have been shown to activate regions of visual cortex that subserve the perception of visual events. Here fMRI was used to examine whether imagery‐related visuocortical activity is modulated if imagery content is held constant but there is a change in the memory retrieval strategy used to invoke imagery. Participants were scanned while visualising common objects in two different conditions: (a) recalling recently encoded pictures and (b) based on their knowledge of concrete nouns. Results showed that retrieval‐related activations in frontal cortex were bilateral when pictures were visualised but left‐lateralised when nouns were visualised. In posterior brain regions, both imagery conditions led to activation in the same set of circumscribed areas in left temporal‐parietal cortex, including a region of the left fusiform gyrus that has previously been implicated in visual imagery. These findings suggest that the posterior network activated during imagery did not vary with strategic task‐related changes in the frontal network used to retrieve imagery content from memory.  相似文献   
260.
Protein kinase Mζ (PKMζ) maintains long-term potentiation (LTP) and long-term memory through persistent increases in kinase expression. Early-life adversity is a precursor to adult mood and anxiety disorders, in part, through persistent disruption of emotional memory throughout life. Here we subjected 10- to 16-wk-old male bonnet macaques to adversity by a maternal variable-foraging demand paradigm. We then examined PKMζ expression in their ventral hippocampi as 7- to 12-yr-old adults. Quantitative immunohistochemistry reveals decreased PKMζ in dentate gyrus, CA1, and subiculum of subjects who had experienced early-life adversity due to the unpredictability of maternal care. Adult animals with persistent decrements of PKMζ in ventral hippocampus express timid rather than confrontational responses to a human intruder. Persistent down-regulation of PKMζ in the ventral hippocampus might reduce the capacity for emotional memory maintenance and contribute to the long-lasting emotional effects of early-life adversity.

Early-life adversity is associated with an increased vulnerability to stress-related disorders that is maintained into adulthood, suggesting a very long-lived effect on emotional memory by the early-life event (Coplan et al. 1996). Although several structural and neurochemical sequelae of early-life adversity have been reported (Teicher et al. 2003; Jackowski et al. 2011), the direct effects of early-life adversity on the molecular substrates maintaining long-term memory storage have not been explored.Accumulating evidence supports a crucial role for the autonomously active, atypical protein kinase C (PKC) isoform protein kinase Mζ (PKMζ) in maintaining synaptic long-term potentiation (LTP), a putative physical substrate for memory, and long-term memory storage (Ling et al. 2002; Pastalkova et al. 2006; Glanzman 2013; Sacktor and Fenton 2018). The autonomous activity of PKMζ is due to its unusual structure that differs from other PKC isoforms (Sacktor et al. 1993). Most PKCs consist of two domains: a catalytic domain and an autoinhibitory regulatory domain that suppresses the catalytic domain. Therefore, most PKCs are inactive until second messengers bind to the regulatory domain and induce a conformational change that releases the autoinhibition. Because second messengers that activate PKCs such as Ca2+ or diacylglycerol have short half-lives, most PKCs are only transiently activated.PKMζ, in contrast, consists of an independent PKCζ catalytic domain, and the absence of an autoinhibitory regulatory domain results in autonomous and thus persistent activity once the kinase is synthesized. PKMζ mRNA is transcribed from an internal promoter within the PKCζ/PKMζ gene that is active only in neural tissue (Hernandez et al. 2003). The mRNA is translationally repressed and transported to dendrites of neurons (Muslimov et al. 2004). High-frequency afferent synaptic activity during LTP induction or learning derepresses PKMζ mRNA translation, triggering new synthesis of PKMζ protein (Osten et al. 1996; Hernandez et al. 2003; Tsokas et al. 2016; Hsieh et al. 2017).Once increased, the steady-state amount of PKMζ remains elevated during LTP or long-term memory maintenance. Recent work with quantitative immunohistochemistry (IHC) shows that spatial conditioning induces persistent increases of PKMζ in somatic and selective dendritic compartments of dorsal hippocampal CA1 pyramidal cells that can last at least 1 mo (Hsieh et al. 2021). The persistent increases are preferentially expressed in CA1 pyramidal cells that were activated during the formation of the memory, specifically at the termination zone of the Schaffer collateral/commissural inputs from subfield CA3. In contrast, persistent PKMζ increases are not evident in stratum lacunosum-moleculare, the termination zone that originates in entorhinal cortex that nonetheless is capable of expressing PKMζ. Postsynaptic domain-specific PKMζ expression patterns hint at distinct circuit-specific modifications of cortical–hippocampal synaptic function by maturational and experiential factors.Persistent changes in PKMζ expression are also associated with changes in the capacity for learning and memory across the life span of animals. Decreased memory ability in aged rats is associated with decreased training-induced, persistent PKMζ expression in prelimbic cortex, and increases in PKMζ are crucial for the cognition-enhancing effects of environmental enrichment in the aged animals (Chen et al. 2016). Hara et al. extended the connection between PKMζ and cognitive function to nonhuman primates (NHPs), showing that levels of PKMζ expression in dentate gyrus (DG) axospinous synapses correlate with successful performance on cognitive tasks in young and aged monkeys (Hara et al. 2012). These studies suggest that persistent down-regulation of PKMζ may comprise an important pathophysiological mechanism for cognitive impairment.Here we used a validated NHP model of early-life adversity, maternal variable-foraging demand (VFD), to explore the links between adversity in infancy and PKMζ expression in adulthood (Coplan et al. 1996; Jackowski et al. 2011). Previous studies of the VFD paradigm have revealed that both infants and their mothers exposed to VFD show significant cerebrospinal fluid (CSF) elevations of the stress neuropeptide, corticotropin-releasing factor (CRF). Moreover, the magnitude of CRF change in mothers and infants are positively correlated, suggesting synchronization of maternal–infant stress responses to the VFD stressor (Coplan et al. 2005). From a behavioral standpoint, maternal social rank plays a negligible role in determining an aggregate score of maternal–infant proximity, suggesting preferential attention of mothers to their infants. During the VFD condition, maternal social rank predicts >80% of the variance of maternal–infant proximity, suggesting mothering patterns are interrupted by preferential orientations to social rank; the latter determines food accessibility (Coplan et al. 2015). Dominant females show relative increases in maternal–infant proximity, whereas subordinate females show relative reductions in maternal–infant proximity. Neither pattern of attachment ameliorates an abnormal association between CSF oxytocin concentrations and hypothalamic-pituitary-adrenal (HPA) axis activity (Coplan et al. 2015). Offspring exposed to VFD rearing assessed both as juveniles and as full adults demonstrate persistent increases in CSF CRF concentrations in comparison with controls reared under non-VFD conditions (Coplan et al. 1996, 2001).Our prior neurohistological studies pointed to the DG as a region particularly vulnerable to VFD exposure, as shown by reduced trophic signaling and neurogenesis (Jackowski et al. 2011; Perera et al. 2011; Schoenfeld et al. 2021). We therefore hypothesized that early-life adversity due to unpredictable maternal care (for brevity, subsequently referred to as “early-life adversity”) reduces the persistent expression of PKMζ within the DG of ventral intrahippocampal neurocircuitry that mediates affective memory processing (Fanselow and Dong 2010). We used PKMζ antisera validated by the lack of immunostaining in PKMζ-null mice (Hsieh et al. 2021) to examine PKMζ expression in ventral hippocampus (NHP anterior hippocampus) in both DG granule cell layer and the stratum moleculare of the suprapyramidal blade that receives direct input from entorhinal cortex, as well as other regions encompassing the hippocampal formation, including the hilus, CA3, CA1, and subiculum.To assess behavioral correlates of hippocampal PKMζ expression, we used a stress-inducing paradigm designed specifically for singly housed bonnet macaque male NHPs, which we refer to as the “human exposure response” (Jackowski et al. 2011; Hamel et al. 2017), which is a variation of the paradigm used in human exposure studies by Kalin et al. in rhesus macaques (Kalin and Shelton 1989). On exposure to a direct human presence, singly housed adult male bonnet macaques react with a dichotomy of responses—confrontational versus timid (see the Materials and Methods) (Jackowski et al. 2011). In our macaque colony, groups of fully adult males are necessarily housed individually to prevent injury sustained during male agonistic encounters, whereas adult females and/or juveniles are safely housed in social groups. Because group housing of nursing females and/or juveniles of both sexes elicits a range of behaviors intrinsic to the species’ social repertoire (Rosenblum et al. 2001; Coplan et al. 2015) that complicates behavioral analyses to human exposure, we restricted our current study to male macaques.  相似文献   
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