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941.
The aim of this study is to investigate whether the fingers are represented separately from the palm. An exogenous spatial
orientation paradigm was used where participants had to detect a tactile stimulus that could appear on the palm, the middle
finger or the ring finger of the left hand. The tactile target was preceded by a non-predictive cue using different stimulus-onset
asynchronies (SOA). We observed a Facilitation Effect in the palm and Inhibition of Return (IOR) for fingers using a short
cue-target SOA, whereas the IOR was found in fingers and palm in long cue-target SOA. Also we observed a ‘Cue above Target’
effect (facilitation effect when the Cue had appeared distal to the target location in a vertical line) at the long SOA. Together,
we suggest that the general pattern of results supports the proposed hypothesis about the different mental representation
of fingers and palms, but with a considerable and hierarchical interrelation between them. 相似文献
942.
Carlos M. P. Sousa Filipe Coelho Encarna Guillamon‐Saorin 《International Journal of Selection & Assessment》2012,20(2):159-170
Employee's self‐efficacy has been related with important outcomes for organizations, such as service quality and job performance. Thus, understanding the antecedents of self‐efficacy can have important payoffs. Accordingly, this paper investigates how personal values interact with autonomy to affect employee's self‐efficacy. The hypotheses are tested with a sample of bank employees. The results reveal that conservation is negatively related to self‐efficacy and that both openness to change and self‐enhancement values have a positive impact on self‐efficacy. Autonomy is also positively associated with self‐efficacy. Finally, autonomy mitigates the negative effects of conservation on self‐efficacy, and strengthens the positive effects of self‐enhancement on self‐efficacy. 相似文献
943.
Objective: Several longitudinal studies had shown that early deprivation and institutionalization during the first six months of life affects the emotional, cognitive, social and neurophysiologic development. Nevertheless, our understanding of possible similar effects of delayed institutionalization, in preschool-age remains unclear to this day. The goal of this study is to evaluate the cognitive performance of institutionalized children with history of preschool-age physical abandonment. Method: 18 male institutionalized children with history of abandonment during the preschool-age (2-5 years old) and comparison group matched by age, handedness, gender, educational and socioeconomic level were tested on multiple tasks of attention, memory and executive functions. Results: We found a cognitive impairment in the institutionalized children in several measures of attention, memory and executive functions. This is the first report of cognitive impairment related to late abandonment and institutionalization effects (after 2 years old), extending the already known effects on early institutionalization. Conclusions: This preliminary study suggests that environmental factors including abandonment and institutional care, can affect not only the infancy period, but also the preschool period providing new insights into our understanding of neurocognitive development. 相似文献
944.
The Aymara of the Andes use absolute (cardinal) frames of reference for describing the relative position of ordinary objects. However, rather than encoding them in available absolute lexemes, they do it in lexemes that are intrinsic to the body: nayra (“front”) and qhipa (“back”), denoting east and west, respectively. Why? We use different but complementary ethnographic methods to investigate the nature of this encoding: (a) linguistic expressions and speech–gesture co‐production, (b) linguistic patterns in the distinct regional Spanish‐based variety Castellano Andino (CA), (c) metaphorical extensions of CA’s spatial patterns to temporal ones, and (d) layouts of traditional houses. Findings indicate that, following fundamental principles of Aymara cosmology, people, objects, and land—as a whole—are conceived as having an implicit canonical orientation facing east, a primary landmark determined by the sunrise. The above bodily based lexicalizations are thus linguistic manifestations of a broader macro‐cultural worldview and its psycho‐cognitive reality. 相似文献
945.
Lack of physical activity (PA) is a risk factor for Alzheimer's disease (AD), and PA interventions are believed to provide an effective non-pharmacological approach for attenuating the symptoms of this disease. However, the mechanism of action of these positive effects is currently unknown. It is possible that the benefits may be at least partially mediated by the effects on the neuroendocrine stress system. Chronic stress can lead to dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis, leading to aberrant basal and circadian patterns of cortisol secretion and a cascade of negative downstream events. These factors have been linked not only to reduced cognitive function but also increased levels of amyloid-β plaques and protein tau "tangles" (the neuropathological hallmarks of AD) in the non-demented mouse models of this disease. However, there is evidence that PA can have restorative effects on the stress neuroendocrine system and related risk factors relevant to AD. We explore the possibility that PA can positively impact upon AD by restoring normative HPA axis function, with consequent downstream effects upon underlying neuropathology and associated cognitive function. We conclude with suggestions for future research to test this hypothesis in patients with AD. 相似文献
946.
Hidalgo V Villada C Almela M Espín L Gómez-Amor J Salvador A 《Stress (Amsterdam, Netherlands)》2012,15(3):329-338
Social stress affects cognitive processes in general, and memory performance in particular. However, the direction of these effects has not been clearly established, as it depends on several factors. Our aim was to determine the impact of the hypothalamus-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) reactivity to psychosocial stress on short-term non-declarative memory and declarative memory performance. Fifty-two young participants (18 men, 34 women) were subjected to the Trier Social Stress Task (TSST) and a control condition in a crossover design. Implicit memory was assessed by a priming test, and explicit memory was assessed by the Rey Auditory Verbal Learning Test (RAVLT). The TSST provoked greater salivary cortisol and salivary alpha-amylase (sAA) responses than the control task. Men had a higher cortisol response to stress than women, but no sex differences were found for sAA release. Stress was associated with an enhancement of priming but did not affect declarative memory. Additionally, the enhancement on the priming test was higher in those whose sAA levels increased more in response to stress (r(48)?=?0.339, p?=?0.018). Our results confirm an effect of acute stress on priming, and that this effect is related to SNS activity. In addition, they suggest a different relationship between stress biomarkers and the different memory systems. 相似文献
947.
Giving difficult news to patients represents a common dilemma for health care professionals. Based on three decades of research, various authors have proposed guidelines outlining the ideal setting, delivery, and timing. Existing publications focus on patients of European descent and may not be applicable in cross-cultural settings. We explored perceptions of Spanish-speaking mothers who have a child with Down syndrome and how they preferred to receive the news of their child's diagnosis. We conducted semi-structured qualitative interviews (n?=?14), which were coded and analyzed by thematic networks to identify common themes. Six significant themes emerged: Cultural Belief System, Communication, Support/Lack of Support, Feelings Engendered, Medical Issues, and Medical System. One overarching theme of mother-child bonding encompassed all sub-themes. The mothers desired the news in a more positive, balanced light and with more complete explanations about the condition. Mothers felt excluded from the diagnostic process and wanted to be better informed about the need for diagnostic studies. Participants used religious beliefs to explain the reason for their child's condition. Many factors influenced Latina mothers' ability to bond initially with their children with Down syndrome. Ideally, these factors should be acknowledged during informing interviews to assist Latino families in adjustment. 相似文献
948.
Schäble S Huston JP Barros M Tomaz C de Souza Silva MA 《Neurobiology of learning and memory》2012,97(2):235-240
Senktide, a potent neurokinin-3 receptor (NK3-R) agonist, increases acetylcholine (ACh) release in the striatum, the prefrontal cortex (Schäble et al., 2011), the amygdala and hippocampus, presumably via postsynaptic mechanisms. A promnestic action of NK3-R agonists has been described in a variety of learning/memory tasks. The memory-enhancing effects of NK3-R agonists and their activating influence on ACh suggest a possible role of the NK3-R in learning and memory via cholinergic modulation. Deterioration of the cholinergic system in the basal forebrain has been associated with learning and memory deficits and cholinergic agents have promnestic effects in a variety of learning paradigms. The anticholinergic drug, scopolamine, a muscarinic ACh receptor antagonist, incurs deficits in a variety of learning tasks and provides a useful tool to investigate the role of the cholinergic systems in mechanisms underlying learning and memory. The aim of this study was to ascertain the effect of the NK3-R agonist, senktide, in the scopolamine-induced deficit model. We hypothesized that senktide treatment would attenuate scopolamine-induced (subcutaneous – s.c. 0.75 mg/kg) memory impairment in three novelty preference paradigms based on spontaneous object exploration: namely object recognition, object–place recognition and object recognition for temporal order. Administration of senktide reversed the scopolamine-induced memory deficits by re-establishing object recognition (s.c. 0.2 mg/kg), object–place recognition (0.2 and 0.4 mg/kg), as well as object recognition for temporal order (0.4 mg/kg) in adult Wistar rats. These results indicate memory enhancing effects of senktide in animals subjected to scopolamine-induced memory impairments and indicate that the promnestic action of NK3-R agonists is mediated by muscarinic cholinergic mechanisms. 相似文献
949.
Martínez MC Alen N Ballarini F Moncada D Viola H 《Neurobiology of learning and memory》2012,98(2):165-173
Recently encoded information can be lost in the presence of new information, a process called 'retrograde interference'. Retrograde interference has been extensively described for more than a century; however, little is known about its underlying mechanisms. Different approaches agree on the need of the synthesis of plasticity related proteins (PRPs) to consolidate a long-term memory (LTM). Our hypothesis is that when PRPs are limited, interference of a task over LTM formation of another may be due to the utilization of protein resources common to both tasks. Here, by combining the tasks of inhibitory avoidance (IA) and open field (OF) exploration in rats, we show that memory traces compete for their stabilization if PRPs are limited. As a result, LTM is formed for only one of the tasks with a consequent decrease in the memory for the other. Furthermore, infusing Arc antisense oligonucleotide into the dorsal hippocampus, we found that Arc is necessary for LTM formation of these two types of learning tasks and is one of the PRPs that can be shared between them when animals are trained in both OF and IA. In sum, these findings suggest that under conditions of reduced protein availability, a learning task interferes with LTM formation of another by using the available PRPs. 相似文献
950.
Klappenbach M Maldonado H Locatelli F Kaczer L 《Learning & memory (Cold Spring Harbor, N.Y.)》2012,19(2):73-83
The understanding of how the reinforcement is represented in the central nervous system during memory formation is a current issue in neurobiology. Several studies in insects provide evidence of the instructive role of biogenic amines during the learning and memory process. In insects it was widely accepted that dopamine (DA) mediates aversive reinforcements. However, the idea of DA being exclusively involved in aversive memory has been challenged in recent studies. Here, we study the involvement of DA during aversive and appetitive memories in the crab Chasmagnathus. We found that DA-receptor antagonists impair aversive memory consolidation, in agreement with previous reports in insects, while administration of DA facilitates memory formation after a weak training protocol. In contrast, DA treatment during appetitive training was found to impair formation of long-term appetitive memory. In addition, as a first step in elucidating the neuroanatomical correlates of DA action on memory, we mapped dopaminergic neurons in the central nervous system of the crab. Results of the current study, together with those obtained in a previous work about the role of octopamine (OA), suggest that both amines (DA and OA) play a dual action in memory processes. On the one hand, DA and OA mediate the aversive and the appetitive signals, respectively, throughout training, while on the other hand, they interfere with the formation of memory of the opposite sign (DA in appetitive and OA in aversive). Our results support a new understanding about the way appetitive and aversive stimuli are processed during memory formation to ensure adaptive behavior. 相似文献