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201.
Some models of the lexicon predict that recognition of words should produce activation spreading to phonologically related words. Consistent with this prediction, Hillinger (1980) demonstrated priming in a visual lexical decision task for word targets preceded by graphemically similar or graphemically dissimilar primes that rhymed with the target. In Experiment 1, we investigated whether this phonological priming effect occurred automatically or because of subject strategies. Although semantically associated primes produced significant facilitation in Experiment 1, no evidence of phonological priming was obtained. Experiments 2 to 5 were conducted in an attempt to obtain the phonological priming effect. Experiment 5 was a replication of one of Hillinger’s experiments. In none of these experiments was phonological priming observed. These results indicate either that the lexicon is not organized such that spreading activation occurs on the basis of phonological similarity, or that visual lexical decisions are made without phonological mediation.  相似文献   
202.
The concept of heightened resilience or invulnerability in young profoundly stressed children is developed in terms of its implications for a psychology of wellness and for primary prevention in mental health. Relevant literature is reviewed, a skeletal model for studying resilience is outlined, and needed research directions are considered. The latter include expansion of the construct's nomological definitional net, inquiry into the antecedents and determinants of resilience, and the application of such generative information to frame preventive interventions for young, profoundly stressed children.  相似文献   
203.
Frontal amnesia and the dysexecutive syndrome   总被引:6,自引:0,他引:6  
This study analyzes the memory deficits shown by an amnesic patient with bilateral frontal damage and a dysexecutive syndrome. He resembles a classic amnesic patient in showing grossly impaired episodic memory for both verbal and nonverbal material, together with normal digit span, and on occasion normal recency in free recall. He differs from the classic amnesic pattern however in showing an impairment in both the speed and accuracy of performance on tests of semantic memory, and in clear evidence for impaired performance on some though not all procedural learning tasks. Finally, his autobiographical memory was poor and subject to substantial confabulation. It is suggested that the pattern of deficits is consistent with a combination of a classic amnesic syndrome with the additional problems associated with the frontal dysexecutive syndrome, rather than exhibiting a qualitatively different form of amnesia.  相似文献   
204.
The perception of an optical flow projected on the ground surface   总被引:3,自引:0,他引:3  
In most experiments in which the importance of visual control on postural stability is studied, optical stimuli attached to vertical surfaces are used. Analyses of long-term standing readjustments generally involve back-and-forth movements of a visual scene or its projection on vertical circular screens. In a natural environment, however, visual information is largely available from the ground. The aim of the experiment reported was to assess the effect of a flow pattern simulating an open outdoor setting on motion perception and postural control. Subjects were presented with an optical texture projected onto the ground. Periods of motionless texture alternated with equivalent durations of unidirectional flows. The change of position of the subject's centre of gravity over time was recorded on a force platform. Results show that the direction of body sway corresponded with that of texture motion. Important aftereffects, as shown in linear vection experiments, were also observed. However, the latency of postural responses was much shorter than with prolonged unidirectional flows produced in other locations of the visual environment. The hypothesis of an ecological specificity of the flows perceived on the ground during terrestrial displacements is discussed.  相似文献   
205.
The relationship between anxiety and depression was examined in a sample of 106 children and adolescents referred to an outpatient anxiety disorder clinic for children. Twenty-eight percent of patients with DSM-III diagnoses of anxiety disorders displayed a concurrent major depression. Children with anxiety disorders plus major depression were found (1) to be older, (2) to demonstrate more severe anxiety symptomatology, and (3) to be diagnosed with different rates of certain anxiety-disorder subtypes, when compared to anxious patients without major depression. Nondepressed anxious children and adolescents did not differ from a psychopathological control group in severity of either anxiety or depression symptoms.  相似文献   
206.
Differences between a clinical sample of younger (ages 5 to 11) and older (ages 12 to 19) children meeting DSM-III criteria for overanxious disorder (OAD) were examined. Younger and older children were compared in terms of (1) the rates of OAD diagnoses occurring in the two age groups, (2) sociodemographic characteristics, (3) symptom expression, (4) association with other forms of maladjustment, and (5) self-reported anxiety and depression. The prevalence of OAD diagnoses and sociodemographic characteristics did not differ. Although younger and older OAD children showed similar rates of most specific DSM-III OAD symptoms, older children presented with a higher total number of overanxious symptoms than younger children. Older children more frequently exhibited a concurrent major depression or simple phobia, whereas younger OAD children more commonly had coexisting separation anxiety or attention deficit disorders. Older OAD children reported significantly higher levels of anxiety and depression on self-report measures. Findings indicated that the expression of OAD varies by developmental level.  相似文献   
207.
We studied the effect of different postoperative times on the behavioral recovery following brain implants. Adult male rats received cortical tissue grafts 2 weeks after aspiration of the medial frontal cortex. Either 2 (Immediate Group) or 28 (Delay Group) days after grafting, the performance of these rats on a behavioral battery, comprising the Morris water maze task, forepaw use, and grooming, was compared to that of rats with similar lesions and postoperative recovery times but no grafts. Rats tested immediately after receiving implants performed better on the spatial navigation task than rats with similar lesions but no grafts. This improvement, however, was less than that shown by rats with lesions but no grafts permitted to recover for 28 days before testing. In contrast, in the Delay Group, rats with grafts were more greatly impaired than were their operated controls. Neither lesions nor grafts affected grooming although the Immediate Group with grafts were significantly more impaired in using their forepaws during feeding than were any of the other groups. These results lead us to conclude that differing postoperative recovery times and task requirements may account for some of the inconsistent results of the influence of brain grafts on behavioral recovery reported in the literature. We also conclude that cortical tissue implants can have two effects with different time courses and opposite net behavioral effects.  相似文献   
208.
Wistar rats of three age groups were tested in an automated tunnel-maze system of variable geometry to investigate whether changes in spontaneous locomotor activity and in learning and memory develop differentially or in a correlated fashion as a function of age. Senescent (30 months) as well as mature-adult (17 months) rats showed an age-correlated decline of locomotor activity as compared to the mature-young (5 months) group. Both working-memory (measured as within-trial arm discrimination performance) and reference-memory (measured as avoidance of "blind alley" visits) were severely affected in the senescent group, whereas the middle-aged animals suffered only from a working-memory deficit. The findings provide evidence that locomotor deficits do not necessarily interfere in the assessment of age-related changes in cognitive performance. Furthermore the results support the hypothesis that working and reference memory have different underlying physiological correlates and that these neuronal systems are differentially affected by the aging process.  相似文献   
209.
Recent research has indicated strong relations between people's appraisals of their circumstances and their emotional states. The present study examined these relations across a range of unpleasant situations in which subjects experienced complex emotional blends. Subjects recalled unpleasant experiences from their pasts that were associated with particular appraisals and described their appraisals and emotions during these experiences. Situations defined by particular appraisals along the human agency or situational control dimensions were reliably associated with different levels of anger, sadness, and guilt, as predicted. However, predicted differences in emotion were not observed for situations selected for appraisals along the certainty or attention dimensions. Most subjects reported experiencing blends of two or more emotions, and correlation/regression analyses indicated that even in the context of these blends, patterns of appraisal similar to those observed previously (Smith & Ellsworth, 1985, 1987) characterized the experience of the individual emotions. The regressions further indicated that appraisals along some dimensions were more important to the experience of particular emotions than were appraisals along other dimensions. Thesecentral appraisals are compared with the adaptive functions their associated emotions are believed to serve, and the implications of these findings are discussed.This research was supported in part by a Stanford University graduate fellowship and in part by a National Institute of Mental Health training grant to Craig Smith. Part of the writing was done while Phoebe Ellsworth was a fellow at the Center for Advanced Study in the Behavioral Sciences, supported by the John D. and Catherine T. MacArthur Foundation and by the James McKeen Cattell Fund.  相似文献   
210.
A right-handed man suffered a left parieto-occipital cerebral infarction, causing agraphia with Gerstmann's syndrome but without major aphasia, alexia, or apraxia. Oral spelling was superior to written spelling. Experiments were performed involving (1) analysis of errors in writing, (2) tasks of visual imagery, and (3) identifying letters drawn without leaving a visual trace. The results suggest that the agraphia and Gerstmann's syndrome are due to a dissociation of language skills and visuospatial skills caused by a dominant parieto-occipital lesion.  相似文献   
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